Permission.psm1


function ConvertTo-ClassExclusionDiv {

    param (

        <#
        Accounts whose objectClass property is in this list are excluded from the HTML report
 
        Note on the 'group' class:
        By default, a group with members is replaced in the report by its members unless the -NoGroupMembers switch is used.
        Any remaining groups are empty and not useful to see in the middle of a list of users/job titles/departments/etc).
        So the 'group' class is excluded here by default.
        #>

        [string[]]$ExcludeClass

    )

    if ($ExcludeClass) {

        $ListGroup = $ExcludeClass |
        ConvertTo-HtmlList |
        ConvertTo-BootstrapListGroup

        $Content = "Accounts whose objectClass property is in this list were excluded from the report.$ListGroup"

    } else {

        $Content = 'No accounts were excluded based on objectClass.'

    }

    Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText 'Accounts Excluded by Class' -Content `$Content"
    return New-BootstrapDivWithHeading -HeadingText 'Accounts Excluded by Class' -Content $Content

}
function ConvertTo-FileList {

    param (
        [string[]]$Format,

        # Path to the folder to save the logs and reports generated by this script
        $OutputDir,

        [cultureinfo]$Culture = (Get-Culture)
    )

    ForEach ($ThisFormat in $Format) {

        # String translations indexed by value in the $Detail parameter
        # TODO: Move to i18n
        $DetailStrings = @(
            'Target paths',
            'Network paths (target path servers and DFS targets resolved)',
            'Item paths (network paths expanded into their children)',
            'Access lists',
            'Access rules (resolved identity references and inheritance flags)',
            'Accounts with access',
            'Expanded access rules (expanded with account info)', # #ToDo: Expand DirectoryEntry objects in the DirectoryEntry and Members properties
            'Formatted permissions',
            'Best Practice issues',
            'Custom sensor output for Paessler PRTG Network Monitor'
            'Permission report'
        )

        switch ($ThisFormat) {

            'csv' {

                ForEach ($Level in $Detail) {

                    # Get shorter versions of the detail strings to use in file names
                    $ShortDetail = $DetailStrings[$Level] -replace '\([^\)]*\)', ''

                    # Convert the shorter strings to Title Case
                    $TitleCaseDetail = $Culture.TextInfo.ToTitleCase($ShortDetail)

                    # Remove spaces from the shorter strings
                    $SpacelessDetail = $TitleCaseDetail -replace '\s', ''

                    # Build the file path
                    "$OutputDir\$Level`_$SpacelessDetail.$ThisFormat"

                }

            }

            'html' {

                ForEach ($Level in $Detail) {

                    # Get shorter versions of the detail strings to use in file names
                    $ShortDetail = $DetailStrings[$Level] -replace '\([^\)]*\)', ''

                    # Convert the shorter strings to Title Case
                    $TitleCaseDetail = $Culture.TextInfo.ToTitleCase($ShortDetail)

                    # Remove spaces from the shorter strings
                    $SpacelessDetail = $TitleCaseDetail -replace '\s', ''

                    # Build the file path
                    "$OutputDir\$Level`_$SpacelessDetail.htm"

                }

            }

            'json' {

                ForEach ($Level in $Detail) {

                    # Get shorter versions of the detail strings to use in file names
                    $ShortDetail = $DetailStrings[$Level] -replace '\([^\)]*\)', ''

                    # Convert the shorter strings to Title Case
                    $TitleCaseDetail = $Culture.TextInfo.ToTitleCase($ShortDetail)

                    # Remove spaces from the shorter strings
                    $SpacelessDetail = $TitleCaseDetail -replace '\s', ''

                    # Build the file path
                    "$OutputDir\$Level`_$SpacelessDetail`_$ThisFormat.htm"

                }

            }

            'prtgxml' {

                $Level = 9

                # Get shorter versions of the detail strings to use in file names
                $ShortDetail = $DetailStrings[$Level] -replace '\([^\)]*\)', ''

                # Convert the shorter strings to Title Case
                $TitleCaseDetail = $Culture.TextInfo.ToTitleCase($ShortDetail)

                # Remove spaces from the shorter strings
                $SpacelessDetail = $TitleCaseDetail -replace '\s', ''

                # Build the file path
                "$OutputDir\$Level`_$SpacelessDetail`_$ThisFormat.xml"

            }

            default {}

        }

    }
}
function ConvertTo-IgnoredDomainDiv {

    param (

        <#
        Domain(s) to ignore (they will be removed from the username)
 
        Can be used:
        to ensure accounts only appear once on the report when they have matching SamAccountNames in multiple domains.
        when the domain is often the same and doesn't need to be displayed
        #>

        [string[]]$IgnoreDomain

    )

    if ($IgnoreDomain) {

        $ListGroup = $IgnoreDomain |
        ConvertTo-HtmlList |
        ConvertTo-BootstrapListGroup

        $Content = "Accounts from these domains are listed in the report without their domain.$ListGroup"

    } else {

        $Content = 'No domains were ignored. All accounts have their domain listed.'

    }

    Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText 'Domains Ignored by Name' -Content `$Content"
    return New-BootstrapDivWithHeading -HeadingText 'Domains Ignored by Name' -Content $Content

}
function ConvertTo-MemberExclusionDiv {

    param (

        <#
        Do not get group members (only report the groups themselves)
 
        Note: By default, the -ExcludeClass parameter will exclude groups from the report.
        If using -NoGroupMembers, you most likely want to modify the value of -ExcludeClass.
        Remove the 'group' class from ExcludeClass in order to see groups on the report.
        #>

        [switch]$NoMembers

    )

    if ($NoMembers) {

        $Content = 'Group members were excluded from the report.<br />Only accounts directly from the ACLs are included in the report.'

    } else {

        $Content = 'No accounts were excluded based on group membership.<br />Members of groups from the ACLs are included in the report.'

    }

    Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText 'Group Members' -Content '$Content'"
    return New-BootstrapDivWithHeading -HeadingText 'Group Members' -Content $Content

}
function ConvertTo-NameExclusionDiv {

    param (

        # Regular expressions matching names of security principals to exclude from the HTML report
        [string[]]$ExcludeAccount

    )

    if ($ExcludeAccount) {

        $ListGroup = $ExcludeAccount |
        ConvertTo-HtmlList |
        ConvertTo-BootstrapListGroup

        $Content = "Accounts whose names match these regular expressions were excluded from the report.$ListGroup"

    } else {

        $Content = 'No accounts were excluded based on name.'

    }

    Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText 'Accounts Excluded by Name' -Content `$Content"
    return New-BootstrapDivWithHeading -HeadingText 'Accounts Excluded by Name' -Content $Content

}
function ConvertTo-PermissionGroup {
    [CmdletBinding()]
    param (

        # Permission object from Expand-Permission
        [PSCustomObject[]]$Permission,

        # Type of output returned to the output stream
        [ValidateSet('csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string]$Format,

        <#
        Level of detail to export to file
            0 Item paths $TargetPath
            1 Resolved item paths (server names resolved, DFS targets resolved) $ACLsByPath.Keys after Resolve-PermissionTarget but before Expand-PermissionTarget
            2 Expanded resolved item paths (parent paths expanded into children) $ACLsByPath.Keys after Expand-PermissionTarget
            3 Access control entries $ACLsByPath.Values after Get-FolderAcl
            4 Resolved access control entries $ACEsByGUID.Values
                                                                                                            $PrincipalsByResolvedID.Values
            5 Expanded resolved access control entries (expanded with info from ADSI security principals) $Permissions
            6 XML custom sensor output for Paessler PRTG Network Monitor
        #>

        [int[]]$Detail = @(0..6),

        [string]$GroupBy,

        [string[]]$AccountProperty = @('Account', 'Name', 'DisplayName', 'Description', 'Department', 'Title'),

        [string[]]$ItemProperty = @('Folder', 'Inheritance')

    )

    $OutputObject = @{}

    switch ($Format) {

        'csv' {
            $OutputObject['Data'] = $Permission | ConvertTo-Csv
        }

        'html' {

            #Write-LogMsg @LogParams -Text "`$Permission | ConvertTo-Html -Fragment | New-BootstrapTable"
            $Html = $Permission | ConvertTo-Html -Fragment
            $OutputObject['Data'] = $Html
            $OutputObject['Table'] = $Html | New-BootstrapTable

        }

        'json' {

            #TODO: Change table id to "Groupings" instead of Folders to allow for Grouping by Account
            $JavaScriptTable = @{
                ID = 'Folders'
            }

            switch ($GroupBy) {

                'account' {
                    $OrderedProperties = $AccountProperty
                    $JavaScriptTable['SearchableColumn'] = $OrderedProperties
                    $Objects = $Permission
                }

                'item' {
                    $OrderedProperties = $ItemProperty
                    $JavaScriptTable['SearchableColumn'] = 'Folder'
                    $JavaScriptTable['DropdownColumn'] = 'Inheritance'
                    $Objects = $Permission
                }

                default { $Objects = $Permission.Values }

            }
            pause
            # Wrap input in a array because output must be a JSON array for jquery to work properly.
            $OutputObject['Data'] = ConvertTo-Json -Compress -InputObject @($Objects)
            $OutputObject['Columns'] = Get-ColumnJson -InputObject $Objects -PropNames $OrderedProperties

            #Write-LogMsg @LogParams -Text "ConvertTo-BootstrapJavaScriptTable -Id 'Folders' -InputObject `$Objects -DataFilterControl -SearchableColumn 'Folder' -DropdownColumn 'Inheritance'"
            $OutputObject['Table'] = ConvertTo-BootstrapJavaScriptTable -InputObject $Objects -PropNames $OrderedProperties -DataFilterControl -PageSize 25 @JavaScriptTable

        }

        'xml' {
            $OutputObject['Data'] = ($Permission | ConvertTo-Xml).InnerXml
        }

        default {}

    }

    return [PSCustomObject]$OutputObject

}
function ConvertTo-PermissionList {

    param (

        # Permission object from Expand-Permission
        [hashtable]$Permission,

        [PSCustomObject[]]$PermissionGrouping,

        # Type of output returned to the output stream
        [ValidateSet('csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string]$Format,

        [string]$ShortestPath,

        [string]$GroupBy,

        [hashtable]$HowToSplit

    )

    # TODO: Replace .Item.Path with GroupingProperty variable somehow
    #$GroupingProperty = @($PermissionGrouping[0] | Get-Member -Type NoteProperty)[0].Name

    switch ($Format) {

        'csv' {

            if (
                $GroupBy -eq 'none' -or
                $HowToSplit[$GroupBy]
            ) {

                [PSCustomObject]@{
                    Data = $Permission.Values | Sort-Object -Property Item, Account | ConvertTo-Csv
                }

            } else {

                switch ($GroupBy) {

                    'account' {

                        ForEach ($Group in $PermissionGrouping) {
                            [PSCustomObject]@{
                                Data = $Permission[$Group.Account.ResolvedAccountName] | ConvertTo-Csv
                            }
                        }

                    }

                    'item' {

                        ForEach ($Group in $PermissionGrouping) {
                            [PSCustomObject]@{
                                Data = $Permission[$Group.Item.Path] | ConvertTo-Csv
                            }
                        }

                    }

                    'target' {

                        ForEach ($Group in $PermissionGrouping) {

                            $Perm = $Permission[$Group.Path]

                            if ($Perm) {
                                [PSCustomObject]@{
                                    Data = $Perm | ConvertTo-Csv
                                }

                            }

                        }

                    }

                }

            }

        }

        'html' {

            if (
                $GroupBy -eq 'none' -or
                $HowToSplit[$GroupBy]
            ) {

                $Heading = New-HtmlHeading 'Permissions' -Level 5
                $Html = $Permission.Values | Sort-Object -Property Item, Account | ConvertTo-Html -Fragment
                $Table = $Html | New-BootstrapTable

                [PSCustomObject]@{
                    Data = $Html
                    Div  = New-BootstrapDiv -Text ($Heading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                }

            } else {

                switch ($GroupBy) {

                    'account' {

                        ForEach ($Group in $PermissionGrouping) {

                            $GroupID = $Group.Account.ResolvedAccountName
                            $Heading = New-HtmlHeading "Folders accessible to $GroupID" -Level 6
                            $StartingPermissions = $Permission[$GroupID]
                            $Html = $StartingPermissions | ConvertTo-Html -Fragment
                            $Table = $Html | New-BootstrapTable

                            [PSCustomObject]@{
                                Data = $Html
                                Div  = New-BootstrapDiv -Text ($Heading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                            }

                        }

                    }

                    'item' {

                        ForEach ($Group in $PermissionGrouping) {

                            $GroupID = $Group.Item.Path
                            $Heading = New-HtmlHeading "Accounts with access to $GroupID" -Level 6
                            $SubHeading = Get-FolderPermissionTableHeader -Group $Group -GroupID $GroupID -ShortestFolderPath $ShortestPath
                            $StartingPermissions = $Permission[$GroupID]
                            $Html = $StartingPermissions | ConvertTo-Html -Fragment
                            $Table = $Html | New-BootstrapTable

                            [PSCustomObject]@{
                                Data = $Html
                                Div  = New-BootstrapDiv -Text ($Heading + $SubHeading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                            }

                        }

                    }

                    'target' {

                        ForEach ($Group in $PermissionGrouping) {

                            $GroupID = $Group.Path
                            $Heading = New-HtmlHeading "Permissions in $GroupID" -Level 5
                            $StartingPermissions = $Permission[$GroupID]
                            $Html = $StartingPermissions | ConvertTo-Html -Fragment
                            $Table = $Html | New-BootstrapTable

                            [PSCustomObject]@{
                                Data = $Html
                                Div  = New-BootstrapDiv -Text ($Heading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                            }

                        }

                    }

                }

            }

        }

        'json' {

            if (
                $GroupBy -eq 'none' -or
                $HowToSplit[$GroupBy]
            ) {

                {

                    $OutputObject = @{}
                    $Heading = New-HtmlHeading 'Permissions' -Level 5
                    $StartingPermissions = $Permission.Values | Sort-Object -Property Item, Account

                    # Remove spaces from property titles
                    $ObjectsForJsonData = ForEach ($Obj in $StartingPermissions) {
                        [PSCustomObject]@{
                            Item              = $Obj.Item
                            Account           = $Obj.Account
                            Access            = $Obj.Access
                            DuetoMembershipIn = $Obj.'Due to Membership In'
                            SourceofAccess    = $Obj.'Source of Access'
                            Name              = $Obj.Name
                            Department        = $Obj.Department
                            Title             = $Obj.Title
                        }

                    }

                    $TableId = 'Perms'
                    $Table = ConvertTo-BootstrapJavaScriptTable -Id $TableId -InputObject $StartingPermissions -DataFilterControl -AllColumnsSearchable -PageSize 25

                    [PSCustomObject]@{
                        Columns = Get-ColumnJson -InputObject $StartingPermissions -PropNames Item, Account, Access, 'Due to Membership In', 'Source of Access', Name, Department, Title
                        Data    = ConvertTo-Json -Compress -InputObject @($ObjectsForJsonData)
                        Div     = New-BootstrapDiv -Text ($Heading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                        Table   = $TableId
                    }

                }

            } else {

                switch ($GroupBy) {

                    'account' {

                        ForEach ($Group in $PermissionGrouping) {

                            $GroupID = $Group.Account.ResolvedAccountName
                            $Heading = New-HtmlHeading "Items accessible to $GroupID" -Level 6
                            $StartingPermissions = $Permission[$GroupID]

                            # Remove spaces from property titles
                            $ObjectsForJsonData = ForEach ($Obj in $StartingPermissions) {
                                [PSCustomObject]@{
                                    Path              = $Obj.Path
                                    Access            = $Obj.Access
                                    DuetoMembershipIn = $Obj.'Due to Membership In'
                                    SourceofAccess    = $Obj.'Source of Access'
                                }
                            }

                            $TableId = "Perms_$($GroupID -replace '[^A-Za-z0-9\-_]', '-')"
                            $Table = ConvertTo-BootstrapJavaScriptTable -Id $TableId -InputObject $StartingPermissions -DataFilterControl -AllColumnsSearchable

                            [PSCustomObject]@{
                                Columns = Get-ColumnJson -InputObject $StartingPermissions-PropNames Path, Access, 'Due to Membership In', 'Source of Access'
                                Data    = ConvertTo-Json -Compress -InputObject @($ObjectsForJsonData)
                                Div     = New-BootstrapDiv -Text ($Heading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                                Table   = $TableId
                            }

                        }

                    }

                    'item' {

                        ForEach ($Group in $PermissionGrouping) {

                            $GroupID = $Group.Item.Path
                            $Heading = New-HtmlHeading "Accounts with access to $GroupID" -Level 6
                            $SubHeading = Get-FolderPermissionTableHeader -Group $Group -GroupID $GroupID -ShortestFolderPath $ShortestPath
                            $StartingPermissions = $Permission[$GroupID]

                            if ($StartingPermissions) {

                                # Remove spaces from property titles
                                $ObjectsForJsonData = ForEach ($Obj in $StartingPermissions) {
                                    [PSCustomObject]@{
                                        Account           = $Obj.Account
                                        Access            = $Obj.Access
                                        DuetoMembershipIn = $Obj.'Due to Membership In'
                                        SourceofAccess    = $Obj.'Source of Access'
                                        Name              = $Obj.Name
                                        Department        = $Obj.Department
                                        Title             = $Obj.Title
                                    }
                                }

                                $TableId = "Perms_$($GroupID -replace '[^A-Za-z0-9\-_]', '-')"
                                $Table = ConvertTo-BootstrapJavaScriptTable -Id $TableId -InputObject $StartingPermissions -DataFilterControl -AllColumnsSearchable

                                [PSCustomObject]@{
                                    Columns = Get-ColumnJson -InputObject $StartingPermissions -PropNames Account, Access, 'Due to Membership In', 'Source of Access', Name, Department, Title
                                    Data    = ConvertTo-Json -Compress -InputObject @($ObjectsForJsonData)
                                    Div     = New-BootstrapDiv -Text ($Heading + $SubHeading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                                    Table   = $TableId
                                }

                            }

                        }

                    }

                    'target' {

                        ForEach ($Group in $PermissionGrouping) {

                            $GroupID = $Group.Path
                            $Heading = New-HtmlHeading "Permissions in $GroupID" -Level 5
                            $StartingPermissions = $Permission[$GroupID]

                            # Remove spaces from property titles
                            $ObjectsForJsonData = ForEach ($Obj in $StartingPermissions) {
                                [PSCustomObject]@{
                                    #Path = $Obj.Item.Path
                                    #Access = ($Obj.Access.Access.Access | Sort-Object -Unique) -join ' ; '
                                    #SourceofAccess = ($Obj.Access.Access.SourceOfAccess | Sort-Object -Unique) -join ' ; '

                                    Item              = $Obj.Item
                                    Account           = $Obj.Account
                                    Access            = $Obj.Access
                                    DuetoMembershipIn = $Obj.'Due to Membership In'
                                    SourceofAccess    = $Obj.'Source of Access'
                                    Name              = $Obj.Name
                                    Department        = $Obj.Department
                                    Title             = $Obj.Title
                                }
                            }

                            $TableId = "Perms_$($GroupID -replace '[^A-Za-z0-9\-_]', '-')"
                            $Table = ConvertTo-BootstrapJavaScriptTable -Id $TableId -InputObject $StartingPermissions -DataFilterControl -AllColumnsSearchable -PageSize 25

                            [PSCustomObject]@{
                                Columns = Get-ColumnJson -InputObject $StartingPermissions -PropNames Item, Account, Access, 'Due to Membership In', 'Source of Access', Name, Department, Title
                                Data    = ConvertTo-Json -Compress -InputObject @($ObjectsForJsonData)
                                Div     = New-BootstrapDiv -Text ($Heading + $Table) -Class 'h-100 p-1 bg-light border rounded-3 table-responsive'
                                Table   = $TableId
                            }

                        }

                    }

                }

            }

        }

        'prtgxml' {

            <#
 
            # ToDo: Users with ownership
            $NtfsIssueParams = @{
                FolderPermissions = $Permission.ItemPermissions
                UserPermissions = $Permission.AccountPermissions
                GroupNameRule = $GroupNameRule
                TodaysHostname = $ThisHostname
                WhoAmI = $WhoAmI
                LogMsgCache = $LogCache
            }
 
            Write-LogMsg @LogParams -Text 'New-NtfsAclIssueReport @NtfsIssueParams'
            $NtfsIssues = New-NtfsAclIssueReport @NtfsIssueParams
 
            # Format the issues as a custom XML sensor for Paessler PRTG Network Monitor
            Write-LogMsg @LogParams -Text "Get-PrtgXmlSensorOutput -NtfsIssues `$NtfsIssues"
            $OutputObject['Data'] = Get-PrtgXmlSensorOutput -NtfsIssues $NtfsIssues
            [PSCustomObject]$OutputObject
            #>


        }

        'xml' {

            if (
                $GroupBy -eq 'none' -or
                $HowToSplit[$GroupBy]
            ) {

                $OutputObject = @{}
                $OutputObject['Data'] = ($Permission.Values | ConvertTo-Xml).InnerXml
                [PSCustomObject]$OutputObject

            } else {

                switch ($GroupBy) {

                    'account' {

                        ForEach ($Group in $PermissionGrouping) {
                            [PSCustomObject]@{
                                Data = ($Permission[$Group.Account.ResolvedAccountName] | ConvertTo-Xml).InnerXml
                            }
                        }

                    }

                    'item' {

                        ForEach ($Group in $PermissionGrouping) {
                            [PSCustomObject]@{
                                Data = ($Permission[$Group.Item.Path] | ConvertTo-Xml).InnerXml
                            }
                        }

                    }

                    'target' {

                        ForEach ($Group in $PermissionGrouping) {
                            [PSCustomObject]@{
                                Data = ($Permission[$Group.Path] | ConvertTo-Xml).InnerXml
                            }
                        }

                    }

                }

            }

        }

    }

}
function ConvertTo-ScriptHtml {

    param (
        $Permission,
        $PermissionGrouping,
        [string]$GroupBy
    )

    $ScriptHtmlBuilder = [System.Text.StringBuilder]::new()

    ForEach ($Group in $Permission) {
        $null = $ScriptHtmlBuilder.AppendLine((ConvertTo-BootstrapTableScript -TableId "#$($Group.Table)" -ColumnJson $Group.Columns -DataJson $Group.Data))
    }

    if ($GroupBy -ne 'none') {
        $null = $ScriptHtmlBuilder.AppendLine((ConvertTo-BootstrapTableScript -TableId '#Folders' -ColumnJson $PermissionGrouping.Columns -DataJson $PermissionGrouping.Data))

    }

    return $ScriptHtmlBuilder.ToString()

}
function Expand-AccountPermissionReference {

    param (

        $Reference,
        $PrincipalsByResolvedID,
        $ACEsByGUID

    )

    ForEach ($Account in $Reference) {

        $Access = ForEach ($PermissionRef in $Account.Access) {

            [PSCustomObject]@{
                Path       = $PermissionRef.Path
                PSTypeName = 'Permission.AccountPermissionItemAccess'
                # Enumerate the list because the returned dictionary value is a list
                Access     = ForEach ($ACE in $ACEsByGUID[$PermissionRef.AceGUIDs]) {
                    $ACE
                }
            }

        }

        [PSCustomObject]@{
            Account    = $PrincipalsByResolvedID[$Account.Account]
            Access     = $Access
            PSTypeName = 'Permission.AccountPermission'
        }

    }

}
function Expand-FlatPermissionReference {

    # Expand each Access Control Entry with the Security Principal for the resolved IdentityReference.

    param (

        $SortedPath,
        $PrincipalsByResolvedID,
        $ACEsByGUID,
        $AceGUIDsByPath

    )

    ForEach ($Item in $SortedPath) {

        $AceGUIDs = $AceGUIDsByPath[$Item]

        if (-not $AceGUIDs) { continue }

        ForEach ($ACE in $ACEsByGUID[$AceGUIDs]) {

            Merge-AceAndPrincipal -ACE $ACE -Principal $PrincipalsByResolvedID[$ACE.IdentityReferenceResolved] -PrincipalsByResolvedID $PrincipalsByResolvedID

        }

    }

}
function Expand-ItemPermissionAccountAccessReference {

    param (
        $Reference,
        [hashtable]$PrincipalsByResolvedID,
        [hashtable]$ACEsByGUID
    )

    ForEach ($PermissionRef in $Reference) {

        [PSCustomObject]@{
            Account    = $PrincipalsByResolvedID[$PermissionRef.Account]
            Access     = $ACEsByGUID[$PermissionRef.AceGUIDs]
            PSTypeName = 'Permission.ItemPermissionAccountAccess'
        }

    }

}
function Expand-ItemPermissionReference {

    param (

        $Reference,
        $PrincipalsByResolvedID,
        $ACEsByGUID,
        $ACLsByPath

    )

    ForEach ($Item in $Reference) {

        [PSCustomObject]@{
            Item       = $ACLsByPath[$Item.Path]
            Access     = Expand-ItemPermissionAccountAccessReference -Reference $Item.Access -ACEsByGUID $ACEsByGUID -PrincipalsByResolvedID $PrincipalsByResolvedID
            PSTypeName = 'Permission.ItemPermission'
        }

    }

}
function Expand-TargetPermissionReference {

    # Expand each Access Control Entry with the Security Principal for the resolved IdentityReference.

    param (

        $Reference,
        $PrincipalsByResolvedID,
        $ACEsByGUID,
        $ACLsByPath,

        # How to group the permissions in the output stream and within each exported file
        [ValidateSet('account', 'item', 'none', 'target')]
        [string]$GroupBy = 'item'

    )

    switch ($GroupBy) {

        'account' {

            ForEach ($Target in $Reference) {

                $TargetProperties = @{
                    PSTypeName = 'Permission.TargetPermission'
                    Path       = $Target.Path
                }

                # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
                $TargetProperties['NetworkPaths'] = ForEach ($NetworkPath in $Target.NetworkPaths) {

                    [pscustomobject]@{
                        Item       = $AclsByPath[$NetworkPath.Path]
                        PSTypeName = 'Permission.ParentItemPermission'
                        Accounts   = Expand-AccountPermissionReference -Reference $NetworkPath.Accounts -ACEsByGUID $ACEsByGUID -PrincipalsByResolvedID $PrincipalsByResolvedID
                    }

                }

                [pscustomobject]$TargetProperties

            }

        }

        'item' {

            ForEach ($Target in $Reference) {

                $TargetProperties = @{
                    PSTypeName = 'Permission.TargetPermission'
                    Path       = $Target.Path
                }

                # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
                $TargetProperties['NetworkPaths'] = ForEach ($NetworkPath in $Target.NetworkPaths) {

                    [pscustomobject]@{
                        Access     = Expand-ItemPermissionAccountAccessReference -Reference $NetworkPath.Access -ACEsByGUID $ACEsByGUID -PrincipalsByResolvedID $PrincipalsByResolvedID
                        Item       = $AclsByPath[$NetworkPath.Path]
                        PSTypeName = 'Permission.ParentItemPermission'
                        Items      = ForEach ($TargetChild in $NetworkPath.Items) {

                            $Access = Expand-ItemPermissionAccountAccessReference -Reference $TargetChild.Access -ACEsByGUID $ACEsByGUID -PrincipalsByResolvedID $PrincipalsByResolvedID

                            if ($Access) {

                                [pscustomobject]@{
                                    Access     = $Access
                                    Item       = $AclsByPath[$TargetChild.Path]
                                    PSTypeName = 'Permission.ChildItemPermission'
                                }

                            }

                        }

                    }

                }

                [pscustomobject]$TargetProperties

            }

        }

        # 'none' and 'target' behave the same
        default {

            $ExpansionParameters = @{
                AceGUIDsByPath         = $AceGUIDsByPath
                ACEsByGUID             = $ACEsByGUID
                PrincipalsByResolvedID = $PrincipalsByResolvedID
            }

            ForEach ($Target in $Reference) {

                $TargetProperties = @{
                    PSTypeName = 'Permission.TargetPermission'
                    Path       = $Target.Path
                }

                # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
                $TargetProperties['NetworkPaths'] = ForEach ($NetworkPath in $Target.NetworkPaths) {

                    [pscustomobject]@{
                        Access     = Expand-FlatPermissionReference -SortedPath $SortedPaths @ExpansionParameters
                        Item       = $AclsByPath[$NetworkPath.Path]
                        PSTypeName = 'Permission.FlatPermission'

                    }

                }

                [pscustomobject]$TargetProperties

            }

        }

    }

}
function Get-ColumnJson {

    # For the JSON that will be used by JavaScript to generate the table
    param (
        $InputObject,
        [string[]]$PropNames,
        [hashtable]$ColumnDefinition = @{
            'Inheritance' = @{
                'width' = '1'
            }
        }
    )

    if (-not $PSBoundParameters.ContainsKey('PropNames')) {
        $PropNames = (@($InputObject)[0] | Get-Member -MemberType noteproperty).Name
    }

    $Columns = ForEach ($Prop in $PropNames) {

        $Props = $ColumnDefinition[$Prop]

        if ($Props) {

            $Props['field'] = $Prop -replace '\s', ''
            $Props['title'] = $Prop

        } else {

            $Props = @{
                'field' = $Prop -replace '\s', ''
                'title' = $Prop
            }

        }

        [PSCustomObject]$Props
    }

    $Columns |
    ConvertTo-Json -Compress

}
function Get-DetailDivHeader {
    param (
        [string]$GroupBy
    )

    switch ($GroupBy) {
        'account' { 'Folders Included in Those Permissions' }
        'item' { 'Accounts Included in Those Permissions' }
        'target' { 'Target Folders Analyzed in This Report' }
        'none' { 'Permissions' }
    }

}
function Get-FolderPermissionTableHeader {
    [OutputType([System.String])]
    param (
        $Group,
        [string]$GroupID,
        [string]$ShortestFolderPath
    )
    $Parent = $GroupID | Split-Path -Parent
    $Leaf = $Parent | Split-Path -Leaf -ErrorAction SilentlyContinue
    if ($Leaf) {
        $ParentLeaf = $Leaf
    } else {
        $ParentLeaf = $Parent
    }
    if ('' -ne $ParentLeaf) {
        if ($Group.Item.AreAccessRulesProtected) {
            return "Inheritance is disabled on this folder. Accounts with access to the parent ($ParentLeaf) and its subfolders cannot access this folder unless they are listed here:"
        } else {
            if ($Group.Item.Path -eq $ShortestFolderPath) {
                return "Inherited permissions from the parent ($ParentLeaf) are included. This folder can only be accessed by the accounts listed here:"
            } else {
                return "Inheritance is enabled on this folder. Accounts with access to the parent ($ParentLeaf) and its subfolders can access this folder. So can the accounts listed here:"
            }
        }
    } else {
        return 'This is the top-level folder. It can only be accessed by the accounts listed here:'
    }
}
function Get-HtmlBody {

    param (
        $NetworkPathDiv,
        $TableOfContents,
        $HtmlFolderPermissions,
        $ReportFooter,
        $HtmlFileList,
        $HtmlExclusions,
        $SummaryDivHeader,
        $DetailDivHeader
    )

    $StringBuilder = [System.Text.StringBuilder]::new()
    $null = $StringBuilder.Append((New-HtmlHeading 'Network Paths' -Level 5))
    $null = $StringBuilder.Append($NetworkPathDiv)

    if ($TableOfContents) {
        $null = $StringBuilder.Append((New-HtmlHeading $SummaryDivHeader -Level 5))
        $null = $StringBuilder.Append($TableOfContents)
    }

    $null = $StringBuilder.Append((New-HtmlHeading $DetailDivHeader -Level 5))

    ForEach ($Perm in $HtmlFolderPermissions) {
        $null = $StringBuilder.Append($Perm)
    }

    if ($HtmlExclusions) {
        $null = $StringBuilder.Append((New-HtmlHeading "Exclusions from This Report" -Level 5))
        $null = $StringBuilder.Append($HtmlExclusions)
    }

    $null = $StringBuilder.Append((New-HtmlHeading "Files Generated" -Level 5))
    $null = $StringBuilder.Append($HtmlFileList)
    $null = $StringBuilder.Append($ReportFooter)

    return $StringBuilder.ToString()

}
function Get-HtmlReportElements {

    # missing

    param (

        # Regular expressions matching names of security principals to exclude from the HTML report
        [string[]]$ExcludeAccount,

        # Accounts whose objectClass property is in this list are excluded from the HTML report
        [string[]]$ExcludeClass = @('group', 'computer'),

        <#
        Domain(s) to ignore (they will be removed from the username)
 
        Intended when a user has matching SamAccountNames in multiple domains but you only want them to appear once on the report.
 
        Can also be used to remove all domains simply for brevity in the report.
        #>

        $IgnoreDomain,

        # Path to the NTFS folder whose permissions are being exported
        [string[]]$TargetPath,

        # Network Path to the NTFS folder whose permissions are being exported
        $NetworkPath,

        # Group members are not being exported (only the groups themselves)
        [switch]$NoMembers,

        # Path to the folder to save the logs and reports generated by this script
        $OutputDir,

        # NTAccount caption of the user running the script
        $WhoAmI,

        # FQDN of the computer running the script
        $ThisFqdn,

        # Timer to measure progress and performance
        $StopWatch,

        # Title at the top of the HTML report
        $Title,

        $Permission,
        $FormattedPermission,
        $LogParams,
        $RecurseDepth,
        $LogFileList,
        $ReportInstanceId,
        [hashtable]$ACEsByGUID,
        [hashtable]$ACLsByPath,
        $PrincipalsByResolvedID,
        $BestPracticeIssue,
        [string[]]$Parent,

        <#
        Level of detail to export to file
            0 Item paths $TargetPath
            1 Resolved item paths (server names resolved, DFS targets resolved) $Parents
            2 Expanded resolved item paths (parent paths expanded into children) $ACLsByPath.Keys
            3 Access rules $ACLsByPath.Values
            4 Resolved access rules (server names resolved, inheritance flags resolved) $ACEsByGUID.Values | %{$_} | Sort Path,IdentityReferenceResolved
            5 Accounts with access $PrincipalsByResolvedID.Values | %{$_} | Sort ResolvedAccountName
            6 Expanded resolved access rules (expanded with account info) $Permissions
            7 Formatted permissions $FormattedPermissions
            8 Best Practice issues $BestPracticeIssues
            9 XML custom sensor output for Paessler PRTG Network Monitor $PrtgXml
            10 Permission Report
        #>

        [int[]]$Detail = @(0..10),

        <#
        Information about the current culture settings.
        This includes information about the current language settings on the system, such as the keyboard layout, and the
        display format of items such as numbers, currency, and dates.
        #>

        [cultureinfo]$Culture = (Get-Culture),

        # File format(s) to export
        [ValidateSet('csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string[]]$FileFormat = @('csv', 'html', 'js', 'json', 'prtgxml', 'xml'),

        # Type of output returned to the output stream
        [ValidateSet('passthru', 'none', 'csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string]$OutputFormat = 'passthru',

        <#
        How to group the permissions in the output stream and within each exported file
 
            SplitBy GroupBy
            none none $FlatPermissions all in 1 file per $TargetPath
            none account $AccountPermissions all in 1 file per $TargetPath
            none item $ItemPermissions all in 1 file per $TargetPath (default behavior)
 
            item none 1 file per item in $ItemPermissions. In each file, $_.Access | sort account
            item account 1 file per item in $ItemPermissions. In each file, $_.Access | group account | sort name
            item item (same as -SplitBy item -GroupBy none)
 
            account none 1 file per item in $AccountPermissions. In each file, $_.Access | sort path
            account account (same as -SplitBy account -GroupBy none)
            account item 1 file per item in $AccountPermissions. In each file, $_.Access | group item | sort name
        #>

        [ValidateSet('account', 'item', 'none', 'target')]
        [string]$GroupBy = 'item'

    )

    Write-LogMsg @LogParams -Text "Get-ReportDescription -RecurseDepth $RecurseDepth"
    $ReportDescription = Get-ReportDescription -RecurseDepth $RecurseDepth

    $NetworkPathTable = Select-ItemTableProperty -InputObject $NetworkPath -Culture $Culture |
    ConvertTo-Html -Fragment |
    New-BootstrapTable

    $NetworkPathDivHeader = 'Local paths were resolved to UNC paths, and UNC paths were resolved to all DFS folder targets'
    Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText '$NetworkPathDivHeader' -Content `$NetworkPathTable"
    $NetworkPathDiv = New-BootstrapDivWithHeading -HeadingText $NetworkPathDivHeader -Content $NetworkPathTable -Class 'h-100 p-1 bg-light border rounded-3 table-responsive' -HeadingLevel 6

    Write-LogMsg @LogParams -Text "Get-SummaryDivHeader -GroupBy $GroupBy"
    $SummaryDivHeader = Get-SummaryDivHeader -GroupBy $GroupBy

    Write-LogMsg @LogParams -Text "Get-SummaryTableHeader -RecurseDepth $RecurseDepth -GroupBy $GroupBy"
    $SummaryTableHeader = Get-SummaryTableHeader -RecurseDepth $RecurseDepth -GroupBy $GroupBy

    Write-LogMsg @LogParams -Text "Get-DetailDivHeader -GroupBy $GroupBy"
    $DetailDivHeader = Get-DetailDivHeader -GroupBy $GroupBy

    Write-LogMsg @LogParams -Text "New-HtmlHeading 'Target Paths' -Level 5"
    $TargetHeading = New-HtmlHeading 'Target Paths' -Level 5

    # Convert the target path(s) to a Bootstrap alert div
    $TargetPathString = $TargetPath -join '<br />'
    Write-LogMsg @LogParams -Text "New-BootstrapAlert -Class Dark -Text '$TargetPathString'"
    $TargetAlert = New-BootstrapAlert -Class Dark -Text $TargetPathString -AdditionalClasses ' small'

    # Add the target path div to the parameter splat for New-BootstrapReport
    $ReportParameters = @{
        Title       = $Title
        Description = "$TargetHeading $TargetAlert $ReportDescription"
    }

    # Build the divs showing the exclusions specified in the report parameters
    $ExcludedNames = ConvertTo-NameExclusionDiv -ExcludeAccount $ExcludeAccount
    $ExcludedClasses = ConvertTo-ClassExclusionDiv -ExcludeClass $ExcludeClass
    $IgnoredDomains = ConvertTo-IgnoredDomainDiv -IgnoreDomain $IgnoreDomain
    $ExcludedMembers = ConvertTo-MemberExclusionDiv -NoMembers:$NoMembers

    # Arrange the exclusion divs into two Bootstrap columns
    Write-LogMsg @LogParams -Text "New-BootstrapColumn -Html '`$ExcludedMembers`$ExcludedClasses',`$IgnoredDomains`$ExcludedNames"
    $ExclusionsDiv = New-BootstrapColumn -Html "$ExcludedMembers$ExcludedClasses", "$IgnoredDomains$ExcludedNames" -Width 6

    # Convert the list of generated log files to a Bootstrap list group
    $HtmlListOfLogs = $LogFileList |
    Split-Path -Leaf | # the output directory will be shown in a Bootstrap alert so this row removes the path from the file names
    ConvertTo-HtmlList |
    ConvertTo-BootstrapListGroup

    # Prepare headings for 2 columns listing report and log files generated, respectively
    $HtmlReportsHeading = New-HtmlHeading -Text 'Reports' -Level 6
    $HtmlLogsHeading = New-HtmlHeading -Text 'Logs' -Level 6

    # Convert the output directory path to a Boostrap alert
    $HtmlOutputDir = New-BootstrapAlert -Text $OutputDir -Class 'secondary' -AdditionalClasses ' small'

    $ListOfReports = ConvertTo-FileList -Detail $Detail -Format $Formats

    # Convert the list of generated report files to a Bootstrap list group
    $HtmlListOfReports = $ListOfReports |
    Split-Path -Leaf |
    ConvertTo-HtmlList |
    ConvertTo-BootstrapListGroup

    # Arrange the lists of generated files in two Bootstrap columns
    Write-LogMsg @LogParams -Text "New-BootstrapColumn -Html '`$HtmlReportsHeading`$HtmlListOfReports',`$HtmlLogsHeading`$HtmlListOfLogs"
    $HtmlDivOfFileColumns = New-BootstrapColumn -Html "$HtmlReportsHeading$HtmlListOfReports", "$HtmlLogsHeading$HtmlListOfLogs" -Width 6

    # Combine the alert and the columns of generated files inside a Bootstrap div
    Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText 'Output Folder:' -Content '`$HtmlOutputDir`$HtmlDivOfFileColumns'"
    $HtmlDivOfFiles = New-BootstrapDivWithHeading -HeadingText "Output Folder:" -Content "$HtmlOutputDir$HtmlDivOfFileColumns"



    # Generate a footer to include at the bottom of the report
    Write-LogMsg @LogParams -Text "Get-ReportFooter -StopWatch `$StopWatch -ReportInstanceId '$ReportInstanceId' -WhoAmI '$WhoAmI' -ThisFqdn '$ThisFqdn'"
    $FooterParams = @{
        ItemCount        = $ACLsByPath.Keys.Count
        PermissionCount  = (
            @(
                $Permission.AccountPermissions.Access.Access.Count,
                $Permission.ItemPermissions.Access.Access.Count,
                $Permission.TargetPermissions.NetworkPaths.Access.Count
            ) |
            Measure-Object -Maximum
        ).Maximum
        PrincipalCount   = $PrincipalsByResolvedID.Keys.Count
        ReportInstanceId = $ReportInstanceId
        StopWatch        = $StopWatch
        ThisFqdn         = $ThisFqdn
        WhoAmI           = $WhoAmI
    }
    $ReportFooter = Get-HtmlReportFooter @FooterParams

    [PSCustomObject]@{
        ReportFooter       = $ReportFooter
        HtmlDivOfFiles     = $HtmlDivOfFiles
        ExclusionsDiv      = $ExclusionsDiv
        ReportParameters   = $ReportParameters
        DetailDivHeader    = $DetailDivHeader
        SummaryTableHeader = $SummaryTableHeader
        SummaryDivHeader   = $SummaryDivHeader
        NetworkPathDiv     = $NetworkPathDiv
    }

}
function Get-HtmlReportFooter {
    param (

        # Stopwatch that was started when report generation began
        [System.Diagnostics.Stopwatch]$StopWatch,

        # NT Account caption (CONTOSO\User) of the account running this function
        [string]$WhoAmI = (whoami.EXE),

        <#
        FQDN of the computer running this function
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        [uint64]$ItemCount,

        [uint64]$TotalBytes,

        [string]$ReportInstanceId,

        [UInt64]$PermissionCount,

        [UInt64]$PrincipalCount,

        [string[]]$UnitsToResolve = @('day', 'hour', 'minute', 'second')

    )

    $null = $StopWatch.Stop()
    $FinishTime = Get-Date
    $StartTime = $FinishTime.AddTicks(-$StopWatch.ElapsedTicks)
    $TimeZoneName = Get-TimeZoneName -Time $FinishTime
    $Duration = Format-TimeSpan -TimeSpan $StopWatch.Elapsed -UnitsToResolve $UnitsToResolve

    if ($TotalBytes) {
        $Size = " ($($TotalBytes / 1TB) TiB"
    }

    $Text = @"
Report generated by $WhoAmI on $ThisFQDN starting at $StartTime and ending at $FinishTime $TimeZoneName<br />
Processed $PermissionCount permissions for $PrincipalCount accounts on $ItemCount items$Size in $Duration<br />
Report instance: $ReportInstanceId
"@


    New-BootstrapAlert -Class Light -Text $Text -AdditionalClasses ' small'

}
<#
$TagetPath.Count parent folders
$ItemCount total folders including children
$FolderPermissions folders with unique permissions
$Permissions.Count access control entries on those folders
$Identities.Count identities in those access control entries
$FormattedSecurityPrincipals principals represented by those identities
$UniqueAccountPermissions.Count unique accounts after filtering out any specified domain names
$ExpandedAccountPermissions.Count effective permissions belonging to those principals and applying to those folders
#>

function Get-ReportDescription {

    param (
        [int]$RecurseDepth
    )

    switch ($RecurseDepth ) {

        0 {
            'Does not include permissions on subfolders (option was declined)'
        }
        -1 {
            'Includes all subfolders with unique permissions (including ∞ levels of subfolders)'
        }
        default {
            "Includes all subfolders with unique permissions (down to $RecurseDepth levels of subfolders)"
        }

    }

}
function Get-SummaryDivHeader {
    param (
        [string]$GroupBy
    )

    switch ($GroupBy) {
        'account' { 'Accounts with Permissions in This Report' }
        'item' { 'Folders with Permissions in This Report' }
        'target' { 'Target Folders Analyzed in This Report' }
    }

}
function Get-SummaryTableHeader {
    param (
        [int]$RecurseDepth,
        [string]$GroupBy
    )

    switch ($GroupBy) {

        'account' {

            if ($NoMembers) {

                'Includes accounts directly listed in the permissions only (option to include group members was declined)'

            } else {

                'Includes accounts in the permissions, and their group members'

            }

        }

        'item' {

            switch ($RecurseDepth ) {
                0 {
                    'Includes the target folder only (option to report on subfolders was declined)'
                }
                -1 {
                    'Includes the target folder and all subfolders with unique permissions'
                }
                default {
                    "Includes the target folder and $RecurseDepth levels of subfolders with unique permissions"
                }
            }

        }

        'target' { }

    }

}
function Group-AccountPermissionReference {

    param (
        $ID,
        [hashtable]$AceGuidByID,
        [hashtable]$AceByGuid
    )

    ForEach ($Identity in ($ID | Sort-Object)) {

        $ItemPaths = @{}

        ForEach ($Guid in $AceGuidByID[$Identity]) {

            $Ace = $AceByGuid[$Guid]
            Add-CacheItem -Cache $ItemPaths -Key $Ace.Path -Value $Guid -Type ([guid])

        }

        [PSCustomObject]@{
            Account = $Identity
            Access  = ForEach ($Item in ($ItemPaths.Keys | Sort-Object)) {

                [PSCustomObject]@{
                    Path     = $Item
                    AceGUIDs = $ItemPaths[$Item]
                }

            }

        }

    }

}
function Group-ItemPermissionReference {

    param (
        $SortedPath,
        $AceGUIDsByPath,
        $ACEsByGUID,
        $PrincipalsByResolvedID,
        [hashtable]$Property = @{}
    )

    ForEach ($ItemPath in $SortedPath) {

        $Property['Path'] = $ItemPath
        $IDsWithAccess = Find-ResolvedIDsWithAccess -ItemPath $ItemPath -AceGUIDsByPath $AceGUIDsByPath -ACEsByGUID $ACEsByGUID -PrincipalsByResolvedID $PrincipalsByResolvedID

        $Property['Access'] = ForEach ($ID in ($IDsWithAccess.Keys | Sort-Object)) {

            [PSCustomObject]@{
                Account  = $ID
                AceGUIDs = $IDsWithAccess[$ID]
            }

        }

        [PSCustomObject]$Property

    }

}
function Group-TargetPermissionReference {

    # Expand each Access Control Entry with the Security Principal for the resolved IdentityReference.

    param (

        [hashtable]$TargetPath,
        [hashtable]$Children,
        $PrincipalsByResolvedID,
        $AceGUIDsByResolvedID,
        $ACEsByGUID,
        $AceGUIDsByPath,
        $ACLsByPath,

        # How to group the permissions in the output stream and within each exported file
        [ValidateSet('account', 'item', 'none', 'target')]
        [string]$GroupBy = 'item'

    )

    $CommonParams = @{
        AceGUIDsByPath         = $AceGUIDsByPath
        ACEsByGUID             = $ACEsByGUID
        PrincipalsByResolvedID = $PrincipalsByResolvedID
    }

    switch ($GroupBy) {

        'account' {

            ForEach ($Target in ($TargetPath.Keys | Sort-Object)) {

                $TargetProperties = @{
                    Path = $Target
                }

                $NetworkPaths = $TargetPath[$Target] | Sort-Object

                $TargetProperties['NetworkPaths'] = ForEach ($NetworkPath in $NetworkPaths) {

                    $ItemsForThisNetworkPath = [System.Collections.Generic.List[string]]::new()
                    $ItemsForThisNetworkPath.Add($NetworkPath)
                    $ItemsForThisNetworkPath.AddRange([string[]]$Children[$NetworkPath])
                    $IDsWithAccess = Find-ResolvedIDsWithAccess -ItemPath $ItemsForThisNetworkPath -AceGUIDsByPath $AceGUIDsByPath -ACEsByGUID $ACEsByGUID -PrincipalsByResolvedID $PrincipalsByResolvedID

                    # Prepare a dictionary for quick lookup of ACE GUIDs for this target
                    $AceGuidsForThisNetworkPath = @{}

                    # Enumerate the collection of ACE GUIDs for this target
                    ForEach ($Guid in $AceGUIDsByPath[$ItemsForThisNetworkPath]) {

                        # Check for null (because we send a list into the dictionary for lookup, we receive a null result for paths that do not exist as a key in the dict)
                        if ($Guid) {

                            # The returned dictionary value is a lists of guids, so we need to enumerate the list
                            ForEach ($ListItem in $Guid) {

                                # Add each GUID to the dictionary for quick lookups
                                $AceGuidsForThisNetworkPath[$ListItem] = $true

                            }

                        }

                    }

                    $AceGuidByIDForThisNetworkPath = @{}

                    ForEach ($ID in $IDsWithAccess.Keys) {

                        $IdentityString = [string]$ID
                        $GuidsForThisIDAndNetworkPath = [System.Collections.Generic.List[guid]]::new()

                        ForEach ($Guid in $AceGUIDsByResolvedID[$IdentityString]) {

                            $AceContainsThisID = $AceGuidsForThisNetworkPath[$Guid]

                            if ($AceContainsThisID) {
                                $GuidsForThisIDAndNetworkPath.Add($Guid)
                            }

                        }

                        $AceGuidByIDForThisNetworkPath[$IdentityString] = $GuidsForThisIDAndNetworkPath

                    }

                    [PSCustomObject]@{
                        Path     = $NetworkPath
                        Accounts = Group-AccountPermissionReference -ID $IDsWithAccess.Keys -AceGuidByID $AceGuidByIDForThisNetworkPath -AceByGuid $ACEsByGUID
                    }

                }

                [pscustomobject]$TargetProperties

            }

        }

        'item' {

            ForEach ($Target in ($TargetPath.Keys | Sort-Object)) {

                $TargetProperties = @{
                    Path = $Target
                }

                $NetworkPaths = $TargetPath[$Target] | Sort-Object

                $TargetProperties['NetworkPaths'] = ForEach ($NetworkPath in $NetworkPaths) {

                    $TopLevelItemProperties = @{
                        'Items' = Group-ItemPermissionReference -SortedPath ($Children[$NetworkPath] | Sort-Object) -ACLsByPath $ACLsByPath @CommonParams
                    }

                    Group-ItemPermissionReference -SortedPath $NetworkPath -Property $TopLevelItemProperties -ACLsByPath $ACLsByPath @CommonParams

                }

                [pscustomobject]$TargetProperties

            }

        }

        # 'none' and 'target' behave the same
        default {

            ForEach ($Target in ($TargetPath.Keys | Sort-Object)) {

                $TargetProperties = @{
                    Path = $Target
                }

                $NetworkPaths = $TargetPath[$Target] | Sort-Object

                $TargetProperties['NetworkPaths'] = ForEach ($NetworkPath in $NetworkPaths) {

                    $ItemsForThisNetworkPath = [System.Collections.Generic.List[string]]::new()
                    $ItemsForThisNetworkPath.Add($NetworkPath)
                    $ItemsForThisNetworkPath.AddRange([string[]]$Children[$NetworkPath])

                    [PSCustomObject]@{
                        Path   = $NetworkPath
                        Access = Expand-FlatPermissionReference -SortedPath $ItemsForThisNetworkPath @CommonParams
                    }

                }

                [pscustomobject]$TargetProperties

            }

        }

    }

}
function Memory {
    <#
function SizeOfObj {
    param ([Type]$T, [Object]$thevalue, [System.Runtime.Serialization.ObjectIDGenerator]$gen)
    $type = $T
    [int]$returnval = 0
    if ($type.IsValueType) {
        $nulltype = [Nullable]::GetUnderlyingType($type)
        $returnval = [System.Runtime.InteropServices.Marshal]::SizeOf($nulltype ?? $type)
    } elseif ($null -eq $thevalue) {
        return 0
    } elseif ($thevalue.GetType().Name -eq 'String') {
        $returnval = ([System.Text.Encoding]::Default).GetByteCount([string]$thevalue)
    } elseif (
        $type.IsArray -and
        $type.GetElementType().IsValueType
    ) {
        $returnval = $thevalue.GetLength(0) * [System.Runtime.InteropServices.Marshal]::SizeOf($type.GetElementType())
    } elseif ($thevalue.GetType.Name -eq 'Stream') {
        [System.IO.Stream]$stream = [System.IO.Stream]$thevalue
        $returnval = [int]($stream.Length)
    } elseif ($type.IsSerializable) {
        try {
            [System.IO.MemoryStream]$s = [System.IO.MemoryStream]::new()
            [System.Runtime.Serialization.Formatters.Binary.BinaryFormatter]$formatter = [System.Runtime.Serialization.Formatters.Binary.BinaryFormatter]::new()
            $formatter.Serialize($s, $thevalue)
            $returnval = [int]($s.Length)
        } catch { }
    } elseif ($type.IsClass) {
        $returnval += SizeOfClass -thevalue $thevalue -gen ($gen ?? [System.Runtime.Serialization.ObjectIDGenerator]::new())
    }
    if ($returnval -eq 0) {
        try {
            $returnval = [System.Runtime.InteropServices.Marshal]::SizeOf($thevalue)
        } catch { }
    }
    return $returnval
}
function SizeOf {
    param ($T, $value)
    SizeOfObj -T ($T.GetType()) -thevalue $value -gen $null
}
function SizeOfClass {
    param (
        [Object]$thevalue, [System.Runtime.Serialization.ObjectIDGenerator]$gen
    )
    [bool]$isfirstTime = $null
    $gen.GetId($thevalue, [ref]$isfirstTime)
    if (-not $isfirstTime) { return 0 }
    $fields = $thevalue.GetType().GetFields([System.Reflection.BindingFlags]::NonPublic -bor [System.Reflection.BindingFlags]::Instance)
 
    [int]$returnval = 0
    for ($i = 0; $i -lt $fields.Length; $i++) {
        [Type]$t = $fields[$i].FieldType
        [Object]$v = $fields[$i].GetValue($thevalue)
        $returnval += 4 + (SizeOfObj -T $t -thevalue $v -gen $gen)
    }
    return $returnval
}
 
$Test = @{}
 
$n = 1000000
$i = 0
while ($i -lt $n) {
    $Test[$i] = [pscustomobject]@{prop1 = 'blah'}
    $i++
}
$Size = (SizeOf -t [hashtable] -value $Test)/1KB
"$Size KiB"
#>

}
function Merge-AceAndPrincipal {

    param ($Principal, $ACE, $PrincipalsByResolvedID)

    ForEach ($Member in $Principal.Members) {

        Merge-AceAndPrincipal -ACE $ACE -Principal $PrincipalsByResolvedID[$Member] -PrincipalsByResolvedID $PrincipalsByResolvedID

    }

    $OutputProperties = @{
        PSTypeName = 'Permission.FlatPermission'
        ItemPath   = $ACE.Path
        AdsiPath   = $Principal.Path
    }

    ForEach ($Prop in ($ACE | Get-Member -View All -MemberType Property, NoteProperty).Name) {
        $OutputProperties[$Prop] = $ACE.$Prop
    }

    ForEach ($Prop in ($Principal | Get-Member -View All -MemberType Property, NoteProperty).Name) {
        $OutputProperties[$Prop] = $Principal.$Prop
    }

    [pscustomobject]$OutputProperties

}
function Out-PermissionDetailReport {

    param (
        [int[]]$Detail,
        [hashtable]$ReportObject,
        [scriptblock[]]$DetailExport,
        [string]$Format,
        [string]$OutputDir,
        [cultureinfo]$Culture,
        [string]$DetailString,
        [string]$FileName,
        [string]$FormatToReturn = 'js',
        [int]$LevelToReturn = 10
    )

    switch ($Format) {
        'csv' { $Suffix = '.csv' ; break }
        'html' { $Suffix = "_$FileName.htm" ; break }
        'js' { $Suffix = "_$Format`_$FileName.htm" ; break }
        'json' { $Suffix = "_$Format`_$FileName.json" ; break }
        'prtgxml' { $Suffix = '.xml' ; break }
        'xml' { $Suffix = '.xml' ; break }
    }

    ForEach ($Level in $Detail) {

        # Get shorter versions of the detail strings to use in file names
        $ShortDetail = $DetailString[$Level] -replace '\([^\)]*\)', ''

        # Convert the shorter strings to Title Case
        $TitleCaseDetail = $Culture.TextInfo.ToTitleCase($ShortDetail)

        # Remove spaces from the shorter strings
        $SpacelessDetail = $TitleCaseDetail -replace '\s', ''

        # Build the file path
        $ThisReportFile = "$OutputDir\$Level`_$SpacelessDetail$Suffix"

        # Generate the report
        $Report = $ReportObject[$Level]

        # Save the report
        $null = Invoke-Command -ScriptBlock $DetailExport[$Level] -ArgumentList $Report, $ThisReportFile

        # Output the name of the report file to the Information stream
        Write-Information $ThisReportFile

        # Return the report file path of the highest level for the Interactive switch of Export-Permission
        if ($Level -eq $LevelToReturn -and $Format -eq $FormatToReturn) {
            $ThisReportFile
        }

    }

}
function Resolve-GroupByParameter {
    param (

        # How to group the permissions in the output stream and within each exported file
        [ValidateSet('account', 'item', 'none', 'target')]
        [string]$GroupBy = 'item',

        [hashtable]$HowToSplit

    )

    if (
        $GroupBy -eq 'none' -or
        $HowToSplit[$GroupBy]
    ) {

        return @{
            Property = 'Access'
            Script   = [scriptblock]::create("Select-PermissionTableProperty -InputObject `$args[0] -Culture `$args[1]")
        }

    } else {

        return @{
            Property = "$GroupBy`s"
            Script   = [scriptblock]::create("Select-$GroupBy`TableProperty -InputObject `$args[0] -Culture `$args[1]")
        }

    }

}
function Resolve-SplitByParameter {

    param (

        <#
        How to split up the exported files:
            none generate a single file with all permissions
            target generate a file per target
            item generate a file per item
            account generate a file per account
            all generate 1 file per target and 1 file per item and 1 file per account and 1 file with all permissions.
        #>

        [ValidateSet('none', 'all', 'target', 'item', 'account')]
        [string[]]$SplitBy = 'all'

    )

    $result = @{}

    foreach ($Split in $SplitBy) {

        if ($Split -eq 'none') {

            return @{'none' = $true }

        } elseif ($Split -eq 'all') {

            return @{
                'target'  = $true
                'none'    = $true
                'item'    = $true
                'account' = $true
            }

        } else {

            $result[$Split] = $true

        }

    }

    return $result

}
function Select-AccountTableProperty {

    # For the HTML table

    param (
        $InputObject
    )

    ForEach ($Object in $InputObject) {

        # This appears to be what determines the order of columns in the html report
        [PSCustomObject]@{
            Account     = $Object.Account.ResolvedAccountName
            Name        = $Object.Account.Name
            DisplayName = $Object.Account.DisplayName
            Description = $Object.Account.Description
            Department  = $Object.Account.Department
            Title       = $Object.Account.Title
        }

    }

}
function Select-ItemTableProperty {

    # For the HTML table

    param (
        $InputObject,
        [cultureinfo]$Culture = (Get-Culture)
    )

    ForEach ($Object in $InputObject) {

        [PSCustomObject]@{
            Folder      = $Object.Item.Path
            Inheritance = $Culture.TextInfo.ToTitleCase(-not $Object.Item.AreAccessRulesProtected)
        }

    }

}
function Select-PermissionTableProperty {

    # For the HTML table
    param (
        $InputObject,
        $IgnoreDomain,
        [hashtable]$OutputHash = [hashtable]::Synchronized(@{}),
        [string]$GroupBy
    )

    switch ($GroupBy) {

        'account' {

            ForEach ($Object in $InputObject) {

                $OutputHash[$Object.Account.ResolvedAccountName] = ForEach ($ACE in $Object.Access) {

                    # Each ACE contains the original IdentityReference representing the group the Object is a member of
                    $GroupString = ($ACE.Access.IdentityReferenceResolved | Sort-Object -Unique) -join ' ; '

                    # ToDo: param to allow setting [self] instead of the objects own name for this property
                    #if ($GroupString -eq $Object.Account.ResolvedAccountName) {
                    # $GroupString = '[self]'
                    #} else {
                    ForEach ($IgnoreThisDomain in $IgnoreDomain) {
                        $GroupString = $GroupString -replace "$IgnoreThisDomain\\", ''
                    }
                    #}

                    [pscustomobject]@{
                        'Path'                 = $ACE.Path
                        'Access'               = ($ACE.Access.Access | Sort-Object -Unique) -join ' ; '
                        'Due to Membership In' = $GroupString
                        'Source of Access'     = ($ACE.Access.SourceOfAccess | Sort-Object -Unique) -join ' ; '
                    }

                }

            }

        }

        'item' {

            ForEach ($Object in $InputObject) {

                $OutputHash[$Object.Item.Path] = ForEach ($ACE in $Object.Access) {

                    # Each ACE contains the original IdentityReference representing the group the Object is a member of
                    $GroupString = ($ACE.Access.IdentityReferenceResolved | Sort-Object -Unique) -join ' ; '

                    # ToDo: param to allow setting [self] instead of the objects own name for this property
                    #if ($GroupString -eq $Object.Account.ResolvedAccountName) {
                    # $GroupString = '[self]'
                    #} else {
                    ForEach ($IgnoreThisDomain in $IgnoreDomain) {
                        $GroupString = $GroupString -replace "$IgnoreThisDomain\\", ''
                    }
                    #}

                    [pscustomobject]@{
                        'Account'              = $ACE.Account.ResolvedAccountName
                        'Access'               = ($ACE.Access.Access | Sort-Object -Unique) -join ' ; '
                        'Due to Membership In' = $GroupString
                        'Source of Access'     = ($ACE.Access.SourceOfAccess | Sort-Object -Unique) -join ' ; '
                        'Name'                 = $ACE.Account.Name
                        'Department'           = $ACE.Account.Department
                        'Title'                = $ACE.Account.Title
                    }

                }

            }

        }

        # 'none' and 'target' behave the same
        default {

            ForEach ($Object in $InputObject) {

                $OutputHash[[guid]::NewGuid()] = ForEach ($ACE in $Object) {

                    # Each ACE contains the original IdentityReference representing the group the Object is a member of
                    $GroupString = ($ACE.IdentityReferenceResolved | Sort-Object -Unique) -join ' ; '

                    # ToDo: param to allow setting [self] instead of the objects own name for this property
                    #if ($GroupString -eq $Object.Account.ResolvedAccountName) {
                    # $GroupString = '[self]'
                    #} else {
                    ForEach ($IgnoreThisDomain in $IgnoreDomain) {
                        $GroupString = $GroupString -replace "$IgnoreThisDomain\\", ''
                    }
                    #}

                    [pscustomobject]@{
                        'Item'                 = $Object.ItemPath
                        'Account'              = $ACE.ResolvedAccountName
                        'Access'               = ($ACE.Access | Sort-Object -Unique) -join ' ; '
                        'Due to Membership In' = $GroupString
                        'Source of Access'     = ($ACE.SourceOfAccess | Sort-Object -Unique) -join ' ; '
                        'Name'                 = $ACE.Name
                        'Department'           = $ACE.Department
                        'Title'                = $ACE.Title
                    }

                }

            }

        }

    }

    return $OutputHash

}
function Add-CacheItem {

    # Use a key to get a generic list from a hashtable
    # If it does not exist, create an empty list
    # Add the new item

    param (

        [hashtable]$Cache,

        $Key,

        $Value,

        [type]$Type

    )

    $CacheResult = $Cache[$Key]

    if ($CacheResult) {
        $List = $CacheResult
    } else {
        $Command = "`$List = [System.Collections.Generic.List[$($Type.ToString())]]::new()"
        Invoke-Expression $Command
    }

    $List.Add($Value)
    $Cache[$Key] = $List

}
function ConvertTo-ItemBlock {

    param (

        $ItemPermissions

    )

    $Culture = Get-Culture

    Write-LogMsg @LogParams -Text "`$ObjectsForTable = Select-ItemTableProperty -InputObject `$ItemPermissions -Culture '$Culture'"
    $ObjectsForTable = Select-ItemTableProperty -InputObject $ItemPermissions -Culture $Culture

    Write-LogMsg @LogParams -Text "`$ObjectsForTable | ConvertTo-Html -Fragment | New-BootstrapTable"
    $HtmlTable = $ObjectsForTable |
    ConvertTo-Html -Fragment |
    New-BootstrapTable

    $JsonData = $ObjectsForTable |
    ConvertTo-Json -Compress

    Write-LogMsg @LogParams -Text "Get-ColumnJson -InputObject `$ObjectsForTable"
    $JsonColumns = Get-ColumnJson -InputObject $ObjectsForTable

    Write-LogMsg @LogParams -Text "ConvertTo-BootstrapJavaScriptTable -Id 'Folders' -InputObject `$ObjectsForTable -DataFilterControl -SearchableColumn 'Folder' -DropdownColumn 'Inheritance'"
    $JsonTable = ConvertTo-BootstrapJavaScriptTable -Id 'Folders' -InputObject $ObjectsForTable -DataFilterControl -SearchableColumn 'Folder' -DropdownColumn 'Inheritance'

    return [pscustomobject]@{
        HtmlDiv     = $HtmlTable
        JsonDiv     = $JsonTable
        JsonData    = $JsonData
        JsonColumns = $JsonColumns
    }

}
function Expand-Permission {

    # TODO: If SplitBy account or item, each file needs to include inherited permissions (with default $SplitBy = 'none', the parent folder's inherited permissions are already included)

    param (
        $SortedPaths,
        $SplitBy,
        $GroupBy,
        $AceGUIDsByPath,
        $AceGUIDsByResolvedID,
        $ACEsByGUID,
        $PrincipalsByResolvedID,
        $ACLsByPath,
        [hashtable]$TargetPath,
        [hashtable]$Children
    )

    $HowToSplit = Resolve-SplitByParameter -SplitBy $SplitBy

    $CommonParams = @{
        ACEsByGUID             = $ACEsByGUID
        PrincipalsByResolvedID = $PrincipalsByResolvedID
    }

    if (
        $HowToSplit['account'] -or
        $GroupBy -eq 'account'
    ) {

        # Group reference GUIDs by the name of their associated account.
        $AccountPermissionReferences = Group-AccountPermissionReference -ID $PrincipalsByResolvedID.Keys -AceGuidByID $AceGUIDsByResolvedID -AceByGuid $ACEsByGUID

        # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
        $AccountPermissions = Expand-AccountPermissionReference @CommonParams -Reference $AccountPermissionReferences

    }

    if (
        $HowToSplit['item'] -or
        $GroupBy -eq 'item'
    ) {

        # Group reference GUIDs by the path to their associated item.
        $ItemPermissionReferences = Group-ItemPermissionReference @CommonParams -SortedPath $SortedPaths -AceGUIDsByPath $AceGUIDsByPath -ACLsByPath $ACLsByPath

        # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
        $ItemPermissions = Expand-ItemPermissionReference @CommonParams -Reference $ItemPermissionReferences -ACLsByPath $ACLsByPath

    }

    if (
        $HowToSplit['account'] -or
        $GroupBy -eq 'account'
    ) {

        # Group reference GUIDs by the name of their associated account.
        $AccountPermissionReferences = Group-AccountPermissionReference -ID $PrincipalsByResolvedID.Keys -AceGuidByID $AceGUIDsByResolvedID -AceByGuid $ACEsByGUID

        # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
        $AccountPermissions = Expand-AccountPermissionReference @CommonParams -Reference $AccountPermissionReferences

    }

    if (
        $HowToSplit['item'] -or
        $GroupBy -eq 'item'
    ) {

        # Group reference GUIDs by the path to their associated item.
        $ItemPermissionReferences = Group-ItemPermissionReference @CommonParams -SortedPath $SortedPaths -AceGUIDsByPath $AceGUIDsByPath -ACLsByPath $ACLsByPath

        # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
        $ItemPermissions = Expand-ItemPermissionReference @CommonParams -Reference $ItemPermissionReferences -ACLsByPath $ACLsByPath

    }

    if (
        $HowToSplit['none'] -or
        $GroupBy -eq 'none'
    ) {

        # Expand each Access Control Entry with the Security Principal for the resolved IdentityReference.
        $FlatPermissions = Expand-FlatPermissionReference @CommonParams -SortedPath $SortedPaths -AceGUIDsByPath $AceGUIDsByPath

    }

    if (
        $HowToSplit['target'] -or
        $GroupBy -eq 'target'
    ) {

        # Group reference GUIDs by their associated TargetPath.
        $TargetPermissionReferences = Group-TargetPermissionReference -TargetPath $TargetPath -Children $Children -AceGUIDsByPath $AceGUIDsByPath -ACLsByPath $ACLsByPath -GroupBy $GroupBy -AceGUIDsByResolvedID $AceGUIDsByResolvedID @CommonParams

        # Expand reference GUIDs into their associated Access Control Entries and Security Principals.
        $TargetPermissions = Expand-TargetPermissionReference -Reference $TargetPermissionReferences -GroupBy $GroupBy -ACLsByPath $ACLsByPath @CommonParams

    }

    return [PSCustomObject]@{
        AccountPermissions = $AccountPermissions
        FlatPermissions    = $FlatPermissions
        ItemPermissions    = $ItemPermissions
        TargetPermissions  = $TargetPermissions
        SplitBy            = $HowToSplit
    }

    return [PSCustomObject]@{
        AccountPermissions = $AccountPermissions
        FlatPermissions    = $FlatPermissions
        ItemPermissions    = $ItemPermissions
        TargetPermissions  = $TargetPermissions
        SplitBy            = $HowToSplit
    }

}
function Expand-PermissionTarget {

    # Expand a folder path into the paths of its subfolders

    param (

        <#
        How many levels of subfolder to enumerate
 
            Set to 0 to ignore all subfolders
 
            Set to -1 (default) to recurse infinitely
 
            Set to any whole number to enumerate that many levels
        #>

        [int]$RecurseDepth,

        # Number of asynchronous threads to use
        [uint16]$ThreadCount = ((Get-CimInstance -ClassName CIM_Processor | Measure-Object -Sum -Property NumberOfLogicalProcessors).Sum),

        # Will be sent to the Type parameter of Write-LogMsg in the PsLogMessage module
        [string]$DebugOutputStream = 'Silent',

        # Hostname to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$ThisHostname = (HOSTNAME.EXE),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Hashtable of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # ID of the parent progress bar under which to show progres
        [int]$ProgressParentId,

        [hashtable]$TargetPath

    )

    $Progress = @{
        Activity = 'Expand-PermissionTarget'
    }
    if ($PSBoundParameters.ContainsKey('ProgressParentId')) {
        $Progress['ParentId'] = $ProgressParentId
        $Progress['Id'] = $ProgressParentId + 1
    } else {
        $Progress['Id'] = 0
    }

    $Targets = $TargetPath.Values | ForEach-Object { $_ }
    $TargetCount = $Targets.Count
    Write-Progress @Progress -Status "0% (item 0 of $TargetCount)" -CurrentOperation "Initializing..." -PercentComplete 0

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        WhoAmI       = $WhoAmI
    }

    [hashtable]$Output = [hashtable]::Synchronized(@{})

    $GetSubfolderParams = @{
        LogMsgCache       = $LogMsgCache
        ThisHostname      = $ThisHostname
        DebugOutputStream = $DebugOutputStream
        WhoAmI            = $WhoAmI
        Output            = $Output
        RecurseDepth      = $RecurseDepth
        ErrorAction       = 'Continue'
    }

    if ($ThreadCount -eq 1 -or $TargetCount -eq 1) {

        [int]$ProgressInterval = [math]::max(($TargetCount / 100), 1)
        $IntervalCounter = 0
        $i = 0

        ForEach ($ThisFolder in $Targets) {

            $IntervalCounter++

            if ($IntervalCounter -eq $ProgressInterval) {
                [int]$PercentComplete = $i / $TargetCount * 100
                Write-Progress @Progress -Status "$PercentComplete% (item $($i + 1) of $TargetCount))" -CurrentOperation "Get-Subfolder '$($ThisFolder)'" -PercentComplete $PercentComplete
                $IntervalCounter = 0
            }

            $i++ # increment $i after the progress to show progress conservatively rather than optimistically
            Write-LogMsg @LogParams -Text "Get-Subfolder -TargetPath '$ThisFolder' -RecurseDepth $RecurseDepth"
            Get-Subfolder -TargetPath $ThisFolder @GetSubfolderParams

        }

    } else {

        $SplitThreadParams = @{
            Command           = 'Get-Subfolder'
            InputObject       = $Targets
            InputParameter    = 'TargetPath'
            DebugOutputStream = $DebugOutputStream
            TodaysHostname    = $ThisHostname
            WhoAmI            = $WhoAmI
            LogMsgCache       = $LogMsgCache
            Threads           = $ThreadCount
            AddParam          = $GetSubfolderParams
        }

        Split-Thread @SplitThreadParams

    }

    Write-Progress @Progress -Completed
    return $Output

}
function Find-ResolvedIDsWithAccess {

    param (
        $ItemPath,
        [hashtable]$AceGUIDsByPath,
        [hashtable]$ACEsByGUID,
        [hashtable]$PrincipalsByResolvedID
    )

    $IDsWithAccess = @{}

    ForEach ($Item in $ItemPath) {

        $Guids = $AceGUIDsByPath[$Item]

        # Not all Paths have ACEs in the cache, so we need to test for null results
        if ($Guids) {

            ForEach ($Guid in $Guids) {

                ForEach ($Ace in $ACEsByGUID[$Guid]) {

                    Add-CacheItem -Cache $IDsWithAccess -Key $Ace.IdentityReferenceResolved -Value $Guid -Type ([guid])

                    ForEach ($Member in $PrincipalsByResolvedID[$Ace.IdentityReferenceResolved].Members) {

                        Add-CacheItem -Cache $IDsWithAccess -Key $Member -Value $Guid -Type ([guid])

                    }

                }

            }

        }

    }

    return $IDsWithAccess

}

# Build a list of known ADSI server names to use to populate the caches
# Include the FQDN of the current computer and the known trusted domains
function Find-ServerFqdn {

    param (

        # Known server FQDNs to include in the output
        [string[]]$Known,

        # File paths whose server FQDNs to include in the output
        [hashtable]$TargetPath,

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # ID of the parent progress bar under which to show progres
        [int]$ProgressParentId

    )

    $Progress = @{
        Activity = 'Find-ServerFqdn'
    }
    if ($PSBoundParameters.ContainsKey('ProgressParentId')) {
        $Progress['ParentId'] = $ProgressParentId
        $ProgressId = $ProgressParentId + 1
    } else {
        $ProgressId = 0
    }

    $Progress['Id'] = $ProgressId
    $Count = $TargetPath.Keys.Count
    Write-Progress @Progress -Status "0% (path 0 of $Count)" -CurrentOperation 'Initializing' -PercentComplete 0

    $UniqueValues = @{
        $ThisFqdn = $null
    }

    ForEach ($Value in $Known) {
        $UniqueValues[$Value] = $null
    }

    # Add server names from the ACL paths

    $ProgressStopWatch = [System.Diagnostics.Stopwatch]::new()
    $ProgressStopWatch.Start()
    $LastRemainder = [int]::MaxValue
    $i = 0

    ForEach ($ThisPath in $TargetPath.Keys) {

        $NewRemainder = $ProgressStopWatch.ElapsedTicks % 5000

        if ($NewRemainder -lt $LastRemainder) {

            $LastRemainder = $NewRemainder
            [int]$PercentComplete = $i / $Count * 100
            Write-Progress @Progress -Status "$PercentComplete% (path $($i + 1) of $Count)" -CurrentOperation "Find-ServerNameInPath '$ThisPath'" -PercentComplete $PercentComplete

        }

        $i++ # increment $i after Write-Progress to show progress conservatively rather than optimistically
        $UniqueValues[(Find-ServerNameInPath -LiteralPath $ThisPath -ThisFqdn $ThisFqdn)] = $null
    }

    Write-Progress @Progress -Completed

    return $UniqueValues.Keys

}
function Format-Permission {

    param (

        # Permission object from Expand-Permission
        [PSCustomObject]$Permission,

        <#
        Domain(s) to ignore (they will be removed from the username)
 
        Can be used:
          to ensure accounts only appear once on the report when they have matching SamAccountNames in multiple domains.
          when the domain is often the same and doesn't need to be displayed
        #>

        [string[]]$IgnoreDomain,

        # How to group the permissions in the output stream and within each exported file
        [ValidateSet('account', 'item', 'none', 'target')]
        [string]$GroupBy = 'item',

        # File formats to export
        [ValidateSet('csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string[]]$FileFormat = @('csv', 'html', 'js', 'json', 'prtgxml', 'xml'),

        # Type of output returned to the output stream
        [ValidateSet('passthru', 'none', 'csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string]$OutputFormat = 'passthru',

        [string]$ShortestPath,

        [cultureinfo]$Culture = (Get-Culture)

    )

    $FormattedResults = @{}
    $Formats = Resolve-FormatParameter -FileFormat $FileFormat -OutputFormat $OutputFormat
    $Group = Resolve-GroupByParameter -GroupBy $GroupBy -HowToSplit $Permission.SplitBy

    if ($Permission.SplitBy['account']) {

        $FormattedResults['SplitByAccount'] = ForEach ($Account in $Permission.AccountPermissions) {

            $Selection = $Account

            $OutputProperties = @{
                Account      = $Account.Account
                Path         = $Permission.TargetPermissions.Path.FullName
                NetworkPaths = $Permission.TargetPermissions.NetworkPaths.Item
                passthru     = $Selection
            }

            $PermissionGroupingsWithChosenProperties = Invoke-Command -ScriptBlock $Group['Script'] -ArgumentList $Selection, $Culture
            $PermissionsWithChosenProperties = Select-PermissionTableProperty -InputObject $Selection -IgnoreDomain $IgnoreDomain -GroupBy $GroupBy

            ForEach ($Format in $Formats) {

                $OutputProperties["$Format`Group"] = ConvertTo-PermissionGroup -Format $Format -Permission $PermissionGroupingsWithChosenProperties -GroupBy $GroupBy
                $OutputProperties[$Format] = ConvertTo-PermissionList -Format $Format -Permission $PermissionsWithChosenProperties -PermissionGrouping $Selection -ShortestPath $ShortestPath -GroupBy $GroupBy -HowToSplit $Permission.SplitBy

            }

            [PSCustomObject]$OutputProperties

        }

    }

    if ($Permission.SplitBy['item']) {

        $FormattedResults['SplitByItem'] = ForEach ($Item in $Permission.ItemPermissions) {

            $Selection = $Item.Access

            $OutputProperties = @{
                Item         = $Item.Item
                TargetPaths  = $Permission.TargetPermissions.Path.FullName
                NetworkPaths = $Permission.TargetPermissions.NetworkPaths.Item
                passthru     = $Selection
            }

            $PermissionGroupingsWithChosenProperties = Invoke-Command -ScriptBlock $Group['Script'] -ArgumentList $Selection, $Culture
            $PermissionsWithChosenProperties = Select-PermissionTableProperty -InputObject $Selection -IgnoreDomain $IgnoreDomain -GroupBy $GroupBy

            ForEach ($Format in $Formats) {

                $OutputProperties["$Format`Group"] = ConvertTo-PermissionGroup -Format $Format -Permission $PermissionGroupingsWithChosenProperties -GroupBy $GroupBy
                $OutputProperties[$Format] = ConvertTo-PermissionList -Format $Format -Permission $PermissionsWithChosenProperties -PermissionGrouping $Selection -ShortestPath $ShortestPath -GroupBy $GroupBy -HowToSplit $Permission.SplitBy

            }

            [PSCustomObject]$OutputProperties

        }

    }

    if ($Permission.SplitBy['target']) {

        $FormattedResults['SplitByTarget'] = ForEach ($Target in $Permission.TargetPermissions) {

            [PSCustomObject]@{
                Path         = $Target.Path
                NetworkPaths = ForEach ($NetworkPath in $Target.NetworkPaths) {

                    $Selection = $NetworkPath.$($Group['Property'])

                    $OutputProperties = @{
                        Item     = $NetworkPath.Item
                        passthru = $Selection
                    }

                    $PermissionGroupingsWithChosenProperties = Invoke-Command -ScriptBlock $Group['Script'] -ArgumentList $Selection, $Culture
                    $PermissionsWithChosenProperties = Select-PermissionTableProperty -InputObject $Selection -IgnoreDomain $IgnoreDomain -GroupBy $GroupBy

                    ForEach ($Format in $Formats) {

                        # Use -ErrorAction SilentlyContinue on ConvertTo-PermissionGroup to suppress errors for GroupBy none or target, where grouping is not needed
                        $OutputProperties["$Format`Group"] = ConvertTo-PermissionGroup -Format $Format -Permission $PermissionGroupingsWithChosenProperties -GroupBy $GroupBy -ErrorAction SilentlyContinue

                        $OutputProperties[$Format] = ConvertTo-PermissionList -Format $Format -Permission $PermissionsWithChosenProperties -PermissionGrouping $Selection -ShortestPath $ShortestPath -GroupBy $GroupBy -HowToSplit $Permission.SplitBy

                    }

                    [PSCustomObject]$OutputProperties

                }

            }

        }

    }

    return $FormattedResults

}
function Format-TimeSpan {
    param (
        [timespan]$TimeSpan,
        [string[]]$UnitsToResolve = @('day', 'hour', 'minute', 'second', 'millisecond')
    )
    $StringBuilder = [System.Text.StringBuilder]::new()
    $aUnitWithAValueHasBeenFound = $false
    foreach ($Unit in $UnitsToResolve) {
        if ($TimeSpan."$Unit`s") {
            if ($aUnitWithAValueHasBeenFound) {
                $null = $StringBuilder.Append(", ")
            }
            $aUnitWithAValueHasBeenFound = $true

            if ($TimeSpan."$Unit`s" -eq 1) {
                $null = $StringBuilder.Append("$($TimeSpan."$Unit`s") $Unit")
            } else {
                $null = $StringBuilder.Append("$($TimeSpan."$Unit`s") $Unit`s")
            }
        }
    }
    $StringBuilder.ToString()
}
function Get-AccessControlList {

    # Get folder access control lists
    # Returns an object representing each effective permission on a folder
    # This includes each Access Control Entry in the Discretionary Access List, as well as the folder's Owner

    param (

        # Path to the item whose permissions to export (inherited ACEs will be included)
        [hashtable]$TargetPath,

        # Number of asynchronous threads to use
        [uint16]$ThreadCount = ((Get-CimInstance -ClassName CIM_Processor | Measure-Object -Sum -Property NumberOfLogicalProcessors).Sum),

        # Will be sent to the Type parameter of Write-LogMsg in the PsLogMessage module
        [string]$DebugOutputStream = 'Debug',

        # Hostname to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$TodaysHostname = (HOSTNAME.EXE),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Hashtable of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # Thread-safe cache of items and their owners
        [System.Collections.Concurrent.ConcurrentDictionary[String, PSCustomObject]]$OwnerCache = [System.Collections.Concurrent.ConcurrentDictionary[String, PSCustomObject]]::new(),

        # ID of the parent progress bar under which to show progres
        [int]$ProgressParentId,

        # Cache of access control lists keyed by path
        [hashtable]$AclByPath = [hashtable]::Synchronized(@{})

    )

    $Progress = @{
        Activity = 'Get-AccessControlList'
    }
    if ($PSBoundParameters.ContainsKey('ProgressParentId')) {
        $Progress['ParentId'] = $ProgressParentId
        $ProgressId = $ProgressParentId + 1
    } else {
        $ProgressId = 0
    }
    $Progress['Id'] = $ProgressId
    $ChildProgress = @{
        Activity = 'Get access control lists'
        Id       = $ProgressId + 1
        ParentId = $ProgressId
    }
    $GrandChildProgress = @{
        Activity = 'Get access control lists'
        Id       = $ProgressId + 2
        ParentId = $ProgressId + 1
    }

    Write-Progress @Progress -Status '0% (step 1 of 2) Get access control lists' -CurrentOperation 'Get access control lists' -PercentComplete 0

    $GetDirectorySecurity = @{
        LogMsgCache       = $LogMsgCache
        ThisHostname      = $TodaysHostname
        DebugOutputStream = $DebugOutputStream
        WhoAmI            = $WhoAmI
        OwnerCache        = $OwnerCache
        ACLsByPath        = $AclByPath
    }

    if ($ThreadCount -eq 1) {

        $TargetIndex = 0
        $ParentCount = $TargetPath.Keys.Count

        ForEach ($Parent in $TargetPath.Keys) {

            [int]$PercentComplete = $TargetIndex / $ParentCount * 100
            $TargetIndex++
            Write-Progress @ChildProgress -Status "$PercentComplete% (parent $TargetIndex of $ParentCount) Get access control lists" -CurrentOperation $Parent -PercentComplete $PercentComplete
            Write-Progress @GrandChildProgress -Status "0% (parent) Get-DirectorySecurity -IncludeInherited" -CurrentOperation $Parent -PercentComplete 0
            Get-DirectorySecurity -LiteralPath $Parent -IncludeInherited @GetDirectorySecurity
            $Children = $TargetPath[$Parent]
            $ChildCount = $Children.Count
            [int]$ProgressInterval = [math]::max(($ChildCount / 100), 1)
            $IntervalCounter = 0
            $ChildIndex = 0

            ForEach ($Child in $Children) {

                $IntervalCounter++

                if ($IntervalCounter -eq $ProgressInterval -or $ChildIndex -eq 0) {

                    [int]$PercentComplete = $ChildIndex / $ChildCount * 100
                    Write-Progress @GrandChildProgress -Status "$PercentComplete% (child $($ChildIndex + 1) of $ChildCount) Get-DirectorySecurity" -CurrentOperation $Child -PercentComplete $PercentComplete
                    $IntervalCounter = 0

                }

                $ChildIndex++ # increment $ChildIndex after the progress to show progress conservatively rather than optimistically
                Get-DirectorySecurity -LiteralPath $Child @GetDirectorySecurity

            }

            Write-Progress @GrandChildProgress -Completed

        }

        Write-Progress @ChildProgress -Completed

    } else {

        $SplitThread = @{
            Command           = 'Get-DirectorySecurity'
            InputObject       = $ChildValues
            InputParameter    = 'LiteralPath'
            DebugOutputStream = $DebugOutputStream
            TodaysHostname    = $TodaysHostname
            WhoAmI            = $WhoAmI
            LogMsgCache       = $LogMsgCache
            Threads           = $ThreadCount
            AddParam          = $GetDirectorySecurity

        }

        Split-Thread @SplitThread

    }

    Write-Progress @Progress -Status '50% (step 2 of 2) Find non-inherited owners' -CurrentOperation 'Find non-inherited owners' -PercentComplete 50
    $ChildProgress['Activity'] = 'Get ACL owners'
    $GrandChildProgress['Activity'] = 'Get ACL owners'

    # Then return the owners of any items that differ from their parents' owners
    if ($ThreadCount -eq 1) {

        # Update the cache with ACEs for the item owners (if they do not match the owner of the item's parent folder)
        # First return the owner of the parent item

        $GetOwnerAce = @{
            OwnerCache = $OwnerCache
            ACLsByPath = $AclByPath
        }

        $ParentIndex = 0

        ForEach ($Parent in $TargetPath.Keys) {

            [int]$PercentComplete = $ParentIndex / $ParentCount * 100
            $ParentIndex++
            Write-Progress @ChildProgress -Status "$PercentComplete% (parent $ParentIndex of $ParentCount) Get ACL Owners" -CurrentOperation $Parent -PercentComplete $PercentComplete
            Write-Progress @GrandChildProgress -Status "0% (parent) Get-OwnerAce" -CurrentOperation $Parent -PercentComplete $PercentComplete
            Get-OwnerAce -Item $Parent @GetOwnerAce
            $Children = $TargetPath[$Parent]
            $ChildCount = $Children.Count
            [int]$ProgressInterval = [math]::max(($ChildCount / 100), 1)
            $IntervalCounter = 0
            $ChildIndex = 0

            ForEach ($Child in $Children) {

                $IntervalCounter++

                if ($IntervalCounter -eq $ProgressInterval -or $ChildIndex -eq 0) {

                    [int]$PercentComplete = $ChildIndex / $ChildCount * 100
                    Write-Progress @GrandChildProgress -Status "$PercentComplete% (child $($ChildIndex + 1) of $ChildCount)) Get-OwnerAce" -CurrentOperation $Child -PercentComplete $PercentComplete
                    $IntervalCounter = 0

                }

                $ChildIndex++
                Get-OwnerAce -Item $Child @GetOwnerAce

            }

            Write-Progress @GrandChildProgress -Completed

        }

        Write-Progress @ChildProgress -Completed

    } else {

        $SplitThread = @{
            Command           = 'Get-OwnerAce'
            InputObject       = $ChildValues
            InputParameter    = 'Item'
            DebugOutputStream = $DebugOutputStream
            TodaysHostname    = $TodaysHostname
            WhoAmI            = $WhoAmI
            LogMsgCache       = $LogMsgCache
            Threads           = $ThreadCount
            AddParam          = $GetOwnerAce
        }

        Split-Thread @SplitThread

    }

    Write-Progress @Progress -Completed

}
function Get-CachedCimInstance {

    param (

        # Name of the computer to query via CIM
        [string]$ComputerName,

        # Name of the CIM class whose instances to return
        [string]$ClassName,

        # CIM query to run. Overrides ClassName if used (but not efficiently, so don't use both)
        [string]$Query,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        [Parameter(Mandatory)]
        [string]$KeyProperty,

        [string[]]$CacheByProperty = $KeyProperty

    )

    $LogParams = @{
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        LogMsgCache  = $LogMsgCache
        WhoAmI       = $WhoAmI
    }

    if ($PSBoundParameters.ContainsKey('ClassName')) {
        $InstanceCacheKey = "$ClassName`By$KeyProperty"
    } else {
        $InstanceCacheKey = "$Query`By$KeyProperty"
    }

    $CimCacheResult = $CimCache[$ComputerName]

    if ($CimCacheResult) {

        Write-LogMsg @LogParams -Text " # CIM cache hit for '$ComputerName'"
        $CimCacheSubresult = $CimCacheResult[$InstanceCacheKey]

        if ($CimCacheSubresult) {
            Write-LogMsg @LogParams -Text " # CIM instance cache hit for '$InstanceCacheKey' on '$ComputerName'"
            return $CimCacheSubresult.Values
        } else {
            Write-LogMsg @LogParams -Text " # CIM instance cache miss for '$InstanceCacheKey' on '$ComputerName'"
        }

    } else {
        Write-LogMsg @LogParams -Text " # CIM cache miss for '$ComputerName'"
    }

    $CimSession = Get-CachedCimSession -ComputerName $ComputerName -CimCache $CimCache -ThisFqdn $ThisFqdn @LogParams

    if ($CimSession) {

        if ($PSBoundParameters.ContainsKey('ClassName')) {
            Write-LogMsg @LogParams -Text "Get-CimInstance -ClassName $ClassName -CimSession `$CimSession"
            $CimInstance = Get-CimInstance -ClassName $ClassName -CimSession $CimSession -ErrorAction SilentlyContinue
        }

        if ($PSBoundParameters.ContainsKey('Query')) {
            Write-LogMsg @LogParams -Text "Get-CimInstance -Query '$Query' -CimSession `$CimSession"
            $CimInstance = Get-CimInstance -Query $Query -CimSession $CimSession -ErrorAction SilentlyContinue
        }

        if ($CimInstance) {

            $InstanceCache = [hashtable]::Synchronized(@{})

            ForEach ($Prop in $CacheByProperty) {

                if ($PSBoundParameters.ContainsKey('ClassName')) {
                    $InstanceCacheKey = "$ClassName`By$Prop"
                } else {
                    $InstanceCacheKey = "$Query`By$Prop"
                }

                ForEach ($Instance in $CimInstance) {
                    $InstancePropertyValue = $Instance.$Prop
                    Write-LogMsg @LogParams -Text " # Add '$InstancePropertyValue' to the '$InstanceCacheKey' cache for '$ComputerName'"
                    $InstanceCache[$InstancePropertyValue] = $Instance
                }

                $CimCache[$ComputerName][$InstanceCacheKey] = $InstanceCache

            }

            return $CimInstance

        }

    }

}
function Get-CachedCimSession {

    param (

        # Name of the computer to query via CIM
        [string]$ComputerName,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages
    )

    $LogParams = @{
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        LogMsgCache  = $LogMsgCache
        WhoAmI       = $WhoAmI
    }

    $CimCacheResult = $CimCache[$ComputerName]

    if ($CimCacheResult) {

        Write-LogMsg @LogParams -Text " # CIM cache hit for '$ComputerName'"
        $CimCacheSubresult = $CimCacheResult['CimSession']

        if ($CimCacheSubresult) {
            Write-LogMsg @LogParams -Text " # CIM session cache hit for '$ComputerName'"
            return $CimCacheSubresult
        } else {
            Write-LogMsg @LogParams -Text " # CIM session cache miss for '$ComputerName'"
        }

    } else {

        Write-LogMsg @LogParams -Text " # CIM cache miss for '$ComputerName'"
        $CimCache[$ComputerName] = [hashtable]::Synchronized(@{})

    }

    if (
        $ComputerName -eq $ThisHostname -or
        $ComputerName -eq "$ThisHostname." -or
        $ComputerName -eq $ThisFqdn -or
        $ComputerName -eq "$ThisFqdn." -or
        $ComputerName -eq 'localhost' -or
        $ComputerName -eq '127.0.0.1' -or
        [string]::IsNullOrEmpty($ComputerName)
    ) {
        Write-LogMsg @LogParams -Text '$CimSession = New-CimSession'
        $CimSession = New-CimSession
    } else {
        # If an Active Directory domain is targeted there are no local accounts and CIM connectivity is not expected
        # Suppress errors and return nothing in that case
        Write-LogMsg @LogParams -Text "`$CimSession = New-CimSession -ComputerName $ComputerName"
        $CimSession = New-CimSession -ComputerName $ComputerName -ErrorAction SilentlyContinue
    }

    if ($CimSession) {
        $CimCache[$ComputerName]['CimSession'] = $CimSession
        return $CimSession
    }

}
function Get-FolderPermissionsBlockUNUSED {
    param (

        # Output from Format-FolderPermission in the PsNtfsModule which has already been piped to Group-Object using the Folder property
        $FolderPermissions,

        # Regular expressions matching names of Users or Groups to exclude from the Html report
        [string[]]$ExcludeAccount,

        # Accounts whose objectClass property is in this list are excluded from the HTML report
        [string[]]$ExcludeClass = @('group', 'computer'),

        <#
        Domain(s) to ignore (they will be removed from the username)
 
        Intended when a user has matching SamAccountNames in multiple domains but you only want them to appear once on the report.
 
        Can also be used to remove all domains simply for brevity in the report.
        #>

        [string[]]$IgnoreDomain,

        $ShortestPath

    )

    # Convert the $ExcludeClass array into a dictionary for fast lookups
    $ClassExclusions = @{}
    ForEach ($ThisClass in $ExcludeClass) {
        $ClassExclusions[$ThisClass] = $true
    }

    ForEach ($ThisFolder in $FolderPermissions) {

        $ThisHeading = New-HtmlHeading "Accounts with access to $($ThisFolder.Item.Path)" -Level 6

        $ThisSubHeading = Get-FolderPermissionTableHeader -ThisFolder $ThisFolder -ShortestFolderPath $ShortestPath

        #$FilterContents = @{}

        $FilteredPermissions = $ThisFolder.Access |
        Where-Object -FilterScript {

            # On built-in groups like 'Authenticated Users' or 'Administrators' the SchemaClassName is null but we have an ObjectType instead.
            # TODO: Research where this difference came from, should these be normalized earlier in the process?
            # A user who was found by being a member of a local group not have an ObjectType (because they are not directly part of the AccessControlEntry)
            # They should have their parent group's AccessControlEntry there...do they? Doesn't it have a Group ObjectType there?

            ###if ($_.Group.AccessControlEntry.ObjectType) {
            ### $Schema = @($_.Group.AccessControlEntry.ObjectType)[0]
            ### $Schema = @($_.Group.SchemaClassName)[0]
            # ToDo: SchemaClassName is a real property but may not exist on all objects. ObjectType is my own property. Need to verify+test all usage of both for accuracy.
            # ToDo: Why is $_.Group.SchemaClassName 'user' for the local Administrators group and Authenticated Users group, and it is 'Group' for the TestPC\Owner user?
            ###}

            # Exclude the object whose classes were specified in the parameters
            $SchemaExclusionResult = if ($ExcludeClass.Count -gt 0) {
                ###$ClassExclusions[$Schema]
                $ClassExclusions[$_.Account.SchemaClassName]
            }
            -not $SchemaExclusionResult -and

            # Exclude the objects whose names match the regular expressions specified in the parameters
            ![bool]$(
                ForEach ($RegEx in $ExcludeAccount) {
                    if ($_.Account.ResolvedAccountName -match $RegEx) {
                        #$FilterContents[$_.Account.ResolvedAccountName] += $_ #TODO: IMPLEMENT IN FUTURE WITH HASHTABLE, NOT += which is demonstrative only for now
                        $true
                    }
                }
            )

        }

        # Bugfix #48 https://github.com/IMJLA/Export-Permission/issues/48
        # Sending a dummy object down the line to avoid errors
        # TODO: More elegant solution needed. Downstream code should be able to handle null input.
        # TODO: Why does this suppress errors, but the object never appears in the tables? NOTE: Suspect this is now resolved by using -AsArray on ConvertTo-Json (lack of this was causing single objects to not be an array therefore not be displayed)
        if ($null -eq $FilteredPermissions) {
            $FilteredPermissions = [pscustomobject]@{
                'Account' = 'NoAccountsMatchingCriteria'
                'Access'  = [pscustomobject]@{
                    'IdentityReferenceResolved' = '.'
                    'FileSystemRights'          = '.'
                    'SourceOfAccess'            = '.'
                    'Name'                      = '.'
                    'Department'                = '.'
                    'Title'                     = '.'
                }
            }
        }

        $ObjectsForFolderPermissionTable = Select-ItemPermissionTableProperty -InputObject $FilteredPermissions -IgnoreDomain $IgnoreDomain |
        Sort-Object -Property Account

        $ThisTable = $ObjectsForFolderPermissionTable |
        ConvertTo-Html -Fragment |
        New-BootstrapTable

        $TableId = "Perms_$($ThisFolder.Item.Path -replace '[^A-Za-z0-9\-_]', '-')"

        $ThisJsonTable = ConvertTo-BootstrapJavaScriptTable -Id $TableId -InputObject $ObjectsForFolderPermissionTable -DataFilterControl -AllColumnsSearchable

        # Remove spaces from property titles
        $ObjectsForJsonData = ForEach ($Obj in $ObjectsForFolderPermissionTable) {
            [PSCustomObject]@{
                Account           = $Obj.Account
                Access            = $Obj.Access
                DuetoMembershipIn = $Obj.'Due to Membership In'
                SourceofAccess    = $Obj.'Source of Access'
                Name              = $Obj.Name
                Department        = $Obj.Department
                Title             = $Obj.Title
            }
        }

        [pscustomobject]@{
            HtmlDiv     = New-BootstrapDiv -Text ($ThisHeading + $ThisSubHeading + $ThisTable)
            JsonDiv     = New-BootstrapDiv -Text ($ThisHeading + $ThisSubHeading + $ThisJsonTable)
            JsonColumns = Get-ColumnJson -InputObject $ObjectsForFolderPermissionTable -PropNames Account, Access,
            'Due to Membership In', 'Source of Access', Name, Department, Title
            #JsonData = $ObjectsForJsonData | ConvertTo-Json -AsArray # requires PS6+ , unknown if any performance benefit compared to wrapping in @()
            JsonData    = ConvertTo-Json -InputObject @($ObjectsForJsonData) -Compress
            JsonTable   = $TableId
            Path        = $ThisFolder.Item.Path
        }
    }
}
function Get-PermissionPrincipal {

    param (

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        # Maximum number of concurrent threads to allow
        [int]$ThreadCount = (Get-CimInstance -ClassName CIM_Processor | Measure-Object -Sum -Property NumberOfLogicalProcessors).Sum,

        # Cache of security principals keyed by resolved identity reference. END STATE
        [hashtable]$PrincipalsByResolvedID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entries keyed by their resolved identities. STARTING STATE
        [hashtable]$ACEsByResolvedID = ([hashtable]::Synchronized(@{})),

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        <#
        Dictionary to cache directory entries to avoid redundant lookups
 
        Defaults to an empty thread-safe hashtable
        #>

        [hashtable]$DirectoryEntryCache = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain NetBIOS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByNetbios = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain SIDs as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsBySid = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain DNS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName,AdsiProvider,Win32Accounts properties as values
        [hashtable]$DomainsByFqdn = ([hashtable]::Synchronized(@{})),

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        <#
        Do not get group members (only report the groups themselves)
 
        Note: By default, the -ExcludeClass parameter will exclude groups from the report.
          If using -NoGroupMembers, you most likely want to modify the value of -ExcludeClass.
          Remove the 'group' class from ExcludeClass in order to see groups on the report.
        #>

        [switch]$NoGroupMembers,

        # ID of the parent progress bar under which to show progres
        [int]$ProgressParentId,

        # The current domain
        # Can be passed as a parameter to reduce calls to Get-CurrentDomain
        [string]$CurrentDomain = (Get-CurrentDomain)

    )

    $Progress = @{
        Activity = 'Get-PermissionPrincipal'
    }
    if ($PSBoundParameters.ContainsKey('ProgressParentId')) {
        $Progress['ParentId'] = $ProgressParentId
        $Progress['Id'] = $ProgressParentId + 1
    } else {
        $Progress['Id'] = 0
    }

    [string[]]$IDs = $ACEsByResolvedID.Keys
    $Count = $IDs.Count
    Write-Progress @Progress -Status "0% (identity 0 of $Count)" -CurrentOperation 'Initialize' -PercentComplete 0

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        WhoAmI       = $WhoAmI
    }

    $ADSIConversionParams = @{
        DirectoryEntryCache    = $DirectoryEntryCache
        DomainsBySID           = $DomainsBySID
        DomainsByNetbios       = $DomainsByNetbios
        DomainsByFqdn          = $DomainsByFqdn
        ThisHostName           = $ThisHostName
        ThisFqdn               = $ThisFqdn
        WhoAmI                 = $WhoAmI
        LogMsgCache            = $LogMsgCache
        CimCache               = $CimCache
        DebugOutputStream      = $DebugOutputStream
        PrincipalsByResolvedID = $PrincipalsByResolvedID # end state
        ACEsByResolvedID       = $ACEsByResolvedID # start state
        CurrentDomain          = $CurrentDomain
    }

    if ($ThreadCount -eq 1) {

        if ($NoGroupMembers) {
            $ADSIConversionParams['NoGroupMembers'] = $true
        }

        [int]$ProgressInterval = [math]::max(($Count / 100), 1)
        $IntervalCounter = 0
        $i = 0

        ForEach ($ThisID in $IDs) {

            $IntervalCounter++

            if ($IntervalCounter -eq $ProgressInterval) {

                [int]$PercentComplete = $i / $Count * 100
                Write-Progress @Progress -Status "$PercentComplete% (identity $($i + 1) of $Count) ConvertFrom-IdentityReferenceResolved" -CurrentOperation $ThisID -PercentComplete $PercentComplete
                $IntervalCounter = 0

            }

            $i++
            Write-LogMsg @LogParams -Text "ConvertFrom-IdentityReferenceResolved -IdentityReference '$ThisID'"
            ConvertFrom-IdentityReferenceResolved -IdentityReference $ThisID @ADSIConversionParams

        }

    } else {

        if ($NoGroupMembers) {
            $ADSIConversionParams['AddSwitch'] = 'NoGroupMembers'
        }

        $SplitThreadParams = @{
            Command              = 'ConvertFrom-IdentityReferenceResolved'
            InputObject          = $IDs
            InputParameter       = 'IdentityReference'
            ObjectStringProperty = 'Name'
            TodaysHostname       = $ThisHostname
            WhoAmI               = $WhoAmI
            LogMsgCache          = $LogMsgCache
            Threads              = $ThreadCount
            AddParam             = $ADSIConversionParams
        }

        Write-LogMsg @LogParams -Text "Split-Thread -Command 'ConvertFrom-IdentityReferenceResolved' -InputParameter 'IdentityReference' -InputObject `$IDs"
        Split-Thread @SplitThreadParams

    }

    Write-Progress @Progress -Completed

}
function Get-PrtgXmlSensorOutput {
    param (
        $NtfsIssues
    )

    $Channels = [System.Collections.Generic.List[string]]::new()


    # Build our XML output formatted for PRTG.
    $ChannelParams = @{
        MaxError   = 0.5
        Channel    = 'Folders with inheritance disabled'
        Value      = ($NtfsIssues.FoldersWithBrokenInheritance | Measure-Object).Count
        CustomUnit = 'folders'
    }
    Format-PrtgXmlResult @ChannelParams |
    ForEach-Object { $null = $Channels.Add($_) }

    $ChannelParams = @{
        MaxError   = 0.5
        Channel    = 'ACEs for groups breaking naming convention'
        Value      = ($NtfsIssues.NonCompliantGroups | Measure-Object).Count
        CustomUnit = 'ACEs'
    }
    Format-PrtgXmlResult @ChannelParams |
    ForEach-Object { $null = $Channels.Add($_) }

    $ChannelParams = @{
        MaxError   = 0.5
        Channel    = 'ACEs for users instead of groups'
        Value      = ($NtfsIssues.UserACEs | Measure-Object).Count
        CustomUnit = 'ACEs'
    }
    Format-PrtgXmlResult @ChannelParams |
    ForEach-Object { $null = $Channels.Add($_) }


    $ChannelParams = @{
        MaxError   = 0.5
        Channel    = 'ACEs for unresolvable SIDs'
        Value      = ($NtfsIssues.SIDsToCleanup | Measure-Object).Count
        CustomUnit = 'ACEs'
    }
    Format-PrtgXmlResult @ChannelParams |
    ForEach-Object { $null = $Channels.Add($_) }


    $ChannelParams = @{
        MaxError   = 0.5
        Channel    = "Folders with 'CREATOR OWNER' access"
        Value      = ($NtfsIssues.FoldersWithCreatorOwner | Measure-Object).Count
        CustomUnit = 'folders'
    }
    Format-PrtgXmlResult @ChannelParams |
    ForEach-Object { $null = $Channels.Add($_) }

    Format-PrtgXmlSensorOutput -PrtgXmlResult $Channels -IssueDetected:$($NtfsIssues.IssueDetected)

}
function Get-TimeZoneName {
    param (
        [datetime]$Time,
        [Microsoft.Management.Infrastructure.CimInstance]$TimeZone = (Get-CimInstance -ClassName Win32_TimeZone)
    )
    if ($Time.IsDaylightSavingTime()) {
        return $TimeZone.DaylightName
    } else {
        return $TimeZone.StandardName
    }
}
function Initialize-Cache {

    <#
    Pre-populate caches in memory to avoid redundant ADSI and CIM queries
    Use known ADSI and CIM server FQDNs to populate six caches:
       Three caches of known ADSI directory servers
         The first cache is keyed on domain SID (e.g. S-1-5-2)
         The second cache is keyed on domain FQDN (e.g. ad.contoso.com)
         The first cache is keyed on domain NetBIOS name (e.g. CONTOSO)
       Two caches of known Win32_Account instances
         The first cache is keyed on SID (e.g. S-1-5-2)
         The second cache is keyed on the Caption (NT Account name e.g. CONTOSO\user1)
       Also populate a cache of DirectoryEntry objects for any domains that have them
     This prevents threads that start near the same time from finding the cache empty and attempting costly operations to populate it
     This prevents repetitive queries to the same directory servers
    #>


    param (

        # FQDNs of the ADSI servers to use to populate the cache
        [string[]]$Fqdn,

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        # Maximum number of concurrent threads to allow
        [int]$ThreadCount = (Get-CimInstance -ClassName CIM_Processor | Measure-Object -Sum -Property NumberOfLogicalProcessors).Sum,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        <#
        Dictionary to cache directory entries to avoid redundant lookups
 
        Defaults to an empty thread-safe hashtable
        #>

        [hashtable]$DirectoryEntryCache = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain NetBIOS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByNetbios = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain SIDs as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsBySid = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain DNS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName,AdsiProvider,Win32Accounts properties as values
        [hashtable]$DomainsByFqdn = ([hashtable]::Synchronized(@{})),

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # ID of the parent progress bar under which to show progres
        [int]$ProgressParentId

    )


    $Progress = @{
        Activity = 'Initialize-Cache'
    }
    if ($PSBoundParameters.ContainsKey('ProgressParentId')) {
        $Progress['ParentId'] = $ProgressParentId
        $ProgressId = $ProgressParentId + 1
    } else {
        $ProgressId = 0
    }

    $Progress['Id'] = $ProgressId
    $Count = $ServerFqdns.Count
    Write-Progress -Status "0% (FQDN 0 of $Count)" -CurrentOperation 'Initializing' -PercentComplete 0 @Progress

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        WhoAmI       = $WhoAmI
    }

    $GetAdsiServer = @{
        DirectoryEntryCache = $DirectoryEntryCache
        DomainsByFqdn       = $DomainsByFqdn
        DomainsByNetbios    = $DomainsByNetbios
        DomainsBySid        = $DomainsBySid
        ThisHostName        = $ThisHostName
        ThisFqdn            = $ThisFqdn
        WhoAmI              = $WhoAmI
        LogMsgCache         = $LogMsgCache
        CimCache            = $CimCache
    }

    if ($ThreadCount -eq 1) {

        $ProgressStopWatch = [System.Diagnostics.Stopwatch]::new()
        $ProgressStopWatch.Start()
        $LastRemainder = [int]::MaxValue
        $i = 0

        ForEach ($ThisServerName in $ServerFqdns) {

            $NewRemainder = $ProgressStopWatch.ElapsedTicks % 5000

            if ($NewRemainder -lt $LastRemainder) {

                $LastRemainder = $NewRemainder
                [int]$PercentComplete = $i / $Count * 100
                Write-Progress -Status "$PercentComplete% (FQDN $($i + 1) of $Count) Get-AdsiServer" -CurrentOperation "Get-AdsiServer '$ThisServerName'" -PercentComplete $PercentComplete @Progress

            }

            $i++ # increment $i after Write-Progress to show progress conservatively rather than optimistically
            Write-LogMsg @LogParams -Text "Get-AdsiServer -Fqdn '$ThisServerName'"
            $null = Get-AdsiServer -Fqdn $ThisServerName @GetAdsiServer

        }

    } else {

        $SplitThread = @{
            Command        = 'Get-AdsiServer'
            InputObject    = $ServerFqdns
            InputParameter = 'Fqdn'
            TodaysHostname = $ThisHostname
            WhoAmI         = $WhoAmI
            LogMsgCache    = $LogMsgCache
            Timeout        = 600
            Threads        = $ThreadCount
            AddParam       = $GetAdsiServer
        }

        Write-LogMsg @LogParams -Text "Split-Thread -Command 'Get-AdsiServer' -InputParameter AdsiServer -InputObject @('$($ServerFqdns -join "',")')"
        $null = Split-Thread @SplitThread

    }

    Write-Progress @Progress -Completed

}
function Invoke-PermissionCommand {

    param (

        [string]$Command

    )

    $Steps = [System.Collections.Specialized.OrderedDictionary]::New()
    $Steps.Add(
        'Get the NTAccount caption of the user running the script, with the correct capitalization',
        { HOSTNAME.EXE }
    )
    $Steps.Add(
        'Get the hostname of the computer running the script',
        { Get-CurrentWhoAmI -LogMsgCache $LogMsgCache -ThisHostName $ThisHostname }
    )

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        #Type = $DebugOutputStream
        WhoAmI       = $WhoAmI
    }

    $StepCount = $Steps.Count
    Write-LogMsg @LogParams -Type Verbose -Text $Command
    $ScriptBlock = $Steps[$Command]
    Write-LogMsg @LogParams -Type Debug -Text $ScriptBlock
    Invoke-Command -ScriptBlock $ScriptBlock

}
function Out-PermissionReport {

    # missing

    param (

        # Regular expressions matching names of security principals to exclude from the HTML report
        [string[]]$ExcludeAccount,

        # Accounts whose objectClass property is in this list are excluded from the HTML report
        [string[]]$ExcludeClass = @('group', 'computer'),

        <#
        Domain(s) to ignore (they will be removed from the username)
 
        Intended when a user has matching SamAccountNames in multiple domains but you only want them to appear once on the report.
 
        Can also be used to remove all domains simply for brevity in the report.
        #>

        $IgnoreDomain,

        # Path to the NTFS folder whose permissions are being exported
        [string[]]$TargetPath,

        # Group members are not being exported (only the groups themselves)
        [switch]$NoMembers,

        # Path to the folder to save the logs and reports generated by this script
        $OutputDir,

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        # Expects an NTAccount Name (e.g. DOMAIN\user)
        [string]$WhoAmI = (whoami.EXE),

        # FQDN of the computer running the script
        $ThisFqdn,

        # Timer to measure progress and performance
        $StopWatch,

        # Title at the top of the HTML report
        $Title,

        $Permission,
        $FormattedPermission,
        $LogParams,
        $RecurseDepth,
        $LogFileList,
        $ReportInstanceId,
        [hashtable]$ACEsByGUID,
        [hashtable]$ACLsByPath,
        $PrincipalsByResolvedID,
        $BestPracticeIssue,
        [hashtable]$Parent,

        <#
        Level of detail to export to file
            0 Item paths $TargetPath
            1 Resolved item paths (server names resolved, DFS targets resolved) $Parents
            2 Expanded resolved item paths (parent paths expanded into children) $ACLsByPath.Keys
            3 Access rules $ACLsByPath.Values
            4 Resolved access rules (server names resolved, inheritance flags resolved) $ACEsByGUID.Values | %{$_} | Sort Path,IdentityReferenceResolved
            5 Accounts with access $PrincipalsByResolvedID.Values | %{$_} | Sort ResolvedAccountName
            6 Expanded resolved access rules (expanded with account info) $Permissions
            7 Formatted permissions $FormattedPermissions
            8 Best Practice issues $BestPracticeIssues
            9 XML custom sensor output for Paessler PRTG Network Monitor $PrtgXml
            10 Permission Report
        #>

        [int[]]$Detail = @(0..10),

        <#
        Information about the current culture settings.
        This includes information about the current language settings on the system, such as the keyboard layout, and the
        display format of items such as numbers, currency, and dates.
        #>

        [cultureinfo]$Culture = (Get-Culture),

        # File format(s) to export
        [ValidateSet('csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string[]]$FileFormat = @('csv', 'html', 'js', 'json', 'prtgxml', 'xml'),

        # Type of output returned to the output stream
        [ValidateSet('passthru', 'none', 'csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string]$OutputFormat = 'passthru',

        <#
        How to group the permissions in the output stream and within each exported file
 
            SplitBy GroupBy
            none none $FlatPermissions all in 1 file per $TargetPath
            none account $AccountPermissions all in 1 file per $TargetPath
            none item $ItemPermissions all in 1 file per $TargetPath (default behavior)
 
            item none 1 file per item in $ItemPermissions. In each file, $_.Access | sort account
            item account 1 file per item in $ItemPermissions. In each file, $_.Access | group account | sort name
            item item (same as -SplitBy item -GroupBy none)
 
            account none 1 file per item in $AccountPermissions. In each file, $_.Access | sort path
            account account (same as -SplitBy account -GroupBy none)
            account item 1 file per item in $AccountPermissions. In each file, $_.Access | group item | sort name
        #>

        [ValidateSet('account', 'item', 'none', 'target')]
        [string]$GroupBy = 'item'

    )

    # Determine all formats specified by the parameters
    $Formats = Resolve-FormatParameter -FileFormat $FileFormat -OutputFormat $OutputFormat

    # String translations indexed by value in the $Detail parameter
    # TODO: Move to i18n
    $DetailStrings = @(
        'Item paths',
        'Resolved item paths (server names and DFS targets resolved)'
        'Expanded resolved item paths (resolved target paths expanded into their children)',
        'Access lists',
        'Access rules (resolved identity references and inheritance flags)',
        'Accounts with access',
        'Expanded access rules (expanded with account info)', # #ToDo: Expand DirectoryEntry objects in the DirectoryEntry and Members properties
        'Formatted permissions',
        'Best Practice issues',
        'Custom sensor output for Paessler PRTG Network Monitor'
        'Permission report'
    )

    $UnsplitDetail = $Detail | Where-Object -FilterScript { $_ -le 5 }
    $SplitDetail = $Detail | Where-Object -FilterScript { $_ -gt 5 }

    $DetailScripts = @(
        { $TargetPath },
        { ForEach ($Key in $Parent.Keys) {
                [PSCustomObject]@{
                    OriginalTargetPath  = $Key
                    ResolvedNetworkPath = $Parent[$Key]
                }
            }
        },
        { $ACLsByPath.Keys },
        { $ACLsByPath.Values },
        { ForEach ($val in $ACEsByGUID.Values) { $val } },
        { ForEach ($val in $PrincipalsByResolvedID.Values) { $val } },
        {

            switch ($GroupBy) {
                'account' { $Permission.AccountPermissions }
                'none' { $Permission.FlatPermissions }
                'item' { $Permission.ItemPermissions }
                'target' { $Permission.TargetPermissions }
            }

        },
        { $Permissions.Data },
        { $BestPracticeIssues },
        { $PrtgXml },
        {}
    )

    ForEach ($Split in $Permission.SplitBy.Keys) {

        switch ($Split) {

            'account' {
                $Subproperty = ''
                $FileNameProperty = $Split
                $FileNameSubproperty = 'ResolvedAccountName'
                $ReportFiles = $FormattedPermission["SplitBy$Split"]
            }

            'item' {
                $Subproperty = ''
                $FileNameProperty = $Split
                $FileNameSubproperty = 'Path'
                $ReportFiles = $FormattedPermission["SplitBy$Split"]
            }

            'none' {
                $Subproperty = 'NetworkPaths'
                $FileNameProperty = ''
                $FileNameSubproperty = 'Path'
                $ReportFiles = [PSCustomObject]@{
                    NetworkPaths = $FormattedPermission['SplitByTarget'].NetworkPaths
                    Path         = $FormattedPermission['SplitByTarget'].Path.FullName
                }

            }

            'target' {
                $Subproperty = 'NetworkPaths'
                $FileNameProperty = ''
                $FileNameSubproperty = 'Path'
                $ReportFiles = $FormattedPermission["SplitBy$Split"]
            }

        }

        ForEach ($Format in $Formats) {

            $FormatString = $Format
            $FormatDir = "$OutputDir\$Format"
            $null = New-Item -Path $FormatDir -ItemType Directory -ErrorAction SilentlyContinue

            switch ($Format) {

                'csv' {

                    $DetailExports = @(
                        { $args[0] | Out-File -LiteralPath $args[1] },
                        { $args[0] | Export-Csv -NoTypeInformation -LiteralPath $args[1] },
                        { $args[0] | Out-File -LiteralPath $args[1] },
                        { $args[0] | Export-Csv -NoTypeInformation -LiteralPath $args[1] },
                        { $args[0] | Export-Csv -NoTypeInformation -LiteralPath $args[1] },
                        { $args[0] | Export-Csv -NoTypeInformation -LiteralPath $args[1] },
                        { $args[0] | Export-Csv -NoTypeInformation -LiteralPath $args[1] },
                        { $args[0] | Out-File -LiteralPath $args[1] },
                        { },
                        { },
                        { }
                    )

                    $DetailScripts[10] = { }

                }

                'html' {

                    $DetailExports = @(
                        { $args[0] | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Html -Fragment | Out-File -LiteralPath $args[1] },
                        { $args[0] -join "<br />`r`n" | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Html -Fragment | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Html -Fragment | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Html -Fragment | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Html -Fragment | Out-File -LiteralPath $args[1] },
                        { $args[0] | Out-File -LiteralPath $args[1] },
                        { },
                        { },
                        { $null = Set-Content -LiteralPath $args[1] -Value $args[0] }
                    )

                    $DetailScripts[10] = {

                        if ($Permission.FlatPermissions) {

                            # Combine all the elements into a single string which will be the innerHtml of the <body> element of the report
                            Write-LogMsg @LogParams -Text "Get-HtmlBody -HtmlFolderPermissions `$FormattedPermission.$Format.Div"
                            $Body = Get-HtmlBody @BodyParams

                            # Apply the report template to the generated HTML report body and description
                            $ReportParameters = $HtmlElements.ReportParameters

                            Write-LogMsg @LogParams -Text "New-BootstrapReport @ReportParameters"
                            New-BootstrapReport -Body $Body @ReportParameters

                        } else {

                            # Combine the header and table inside a Bootstrap div
                            Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText '$HtmlElements.SummaryTableHeader' -Content `$FormattedPermission.$Format`Group.Table"
                            $TableOfContents = New-BootstrapDivWithHeading -HeadingText $HtmlElements.SummaryTableHeader -Content $PermissionGroupings.Table -Class 'h-100 p-1 bg-light border rounded-3 table-responsive' -HeadingLevel 6

                            # Combine all the elements into a single string which will be the innerHtml of the <body> element of the report
                            Write-LogMsg @LogParams -Text "Get-HtmlBody -TableOfContents `$TableOfContents -HtmlFolderPermissions `$FormattedPermission.$Format.Div"
                            $Body = Get-HtmlBody -TableOfContents $TableOfContents @BodyParams

                        }

                        $ReportParameters = $HtmlElements.ReportParameters

                        # Apply the report template to the generated HTML report body and description
                        Write-LogMsg @LogParams -Text "New-BootstrapReport @$HtmlElements.ReportParameters"
                        New-BootstrapReport -Body $Body @ReportParameters

                    }

                }

                'js' {

                    $DetailExports = @(
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { },
                        { },
                        { $null = Set-Content -LiteralPath $args[1] -Value $args[0] }
                    )

                    $DetailScripts[10] = {

                        if ($Permission.FlatPermissions) {

                            # Combine all the elements into a single string which will be the innerHtml of the <body> element of the report
                            Write-LogMsg @LogParams -Text "Get-HtmlBody -HtmlFolderPermissions `$FormattedPermission.$Format.Div"
                            $Body = Get-HtmlBody @BodyParams

                        } else {

                            # Combine the header and table inside a Bootstrap div
                            Write-LogMsg @LogParams -Text "New-BootstrapDivWithHeading -HeadingText '$HtmlElements.SummaryTableHeader' -Content `$FormattedPermission.$Format`Group.Table"
                            $TableOfContents = New-BootstrapDivWithHeading -HeadingText $HtmlElements.SummaryTableHeader -Content $PermissionGroupings.Table -Class 'h-100 p-1 bg-light border rounded-3 table-responsive' -HeadingLevel 6

                            # Combine all the elements into a single string which will be the innerHtml of the <body> element of the report
                            Write-LogMsg @LogParams -Text "Get-HtmlBody -TableOfContents `$TableOfContents -HtmlFolderPermissions `$FormattedPermission.$Format.Div"
                            $Body = Get-HtmlBody -TableOfContents $TableOfContents @BodyParams

                        }

                        # Build the JavaScript scripts
                        Write-LogMsg @LogParams -Text "ConvertTo-ScriptHtml -Permission `$Permissions -PermissionGrouping `$PermissionGroupings"
                        $ScriptHtml = ConvertTo-ScriptHtml -Permission $Permissions -PermissionGrouping $PermissionGroupings -GroupBy $GroupBy

                        $ReportParameters = $HtmlElements.ReportParameters

                        # Apply the report template to the generated HTML report body and description
                        Write-LogMsg @LogParams -Text "New-BootstrapReport -JavaScript @$HtmlElements.ReportParameters"
                        New-BootstrapReport -JavaScript -AdditionalScriptHtml $ScriptHtml -Body $Body @ReportParameters

                    }

                    $FormatString = 'json'

                }

                'json' {

                    $DetailExports = @(
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { $args[0] | ConvertTo-Json -Compress -WarningAction SilentlyContinue | Out-File -LiteralPath $args[1] },
                        { },
                        { },
                        { }
                    )

                    $DetailScripts[10] = { }

                }

                'prtgxml' {

                    $DetailExports = @( { }, { }, { }, { }, { }, { }, { }, { }, { }, { } )

                    $DetailScripts[10] = { }

                }

                'xml' {

                    $DetailExports = @(
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { ($args[0] | ConvertTo-Xml).InnerXml | Out-File -LiteralPath $args[1] },
                        { }, { }, { }
                    )

                    $DetailScripts[10] = { }

                }

            }

            $ReportObjects = @{}

            ForEach ($Level in $UnsplitDetail) {

                # Save the report
                $ReportObjects[$Level] = Invoke-Command -ScriptBlock $DetailScripts[$Level]

                Out-PermissionDetailReport -Detail $Level -ReportObject $ReportObjects -DetailExport $DetailExports -Format $Format -OutputDir $FormatDir -Culture $Culture -DetailString $DetailStrings

            }

            ForEach ($File in $ReportFiles) {

                if ($Subproperty -eq '') {
                    $Subfile = $File
                } else {
                    $Subfile = $File.$Subproperty
                }

                if ($FileNameProperty -eq '') {
                    $FileName = $File.$FileNameSubproperty
                } else {
                    $FileName = $File.$FileNameProperty.$FileNameSubproperty
                }

                $FileName = $FileName -replace '\\\\', '' -replace '\\', '_' -replace '\:', ''

                # Convert the list of permission groupings list to an HTML table
                $PermissionGroupings = $Subfile."$FormatString`Group"
                $Permissions = $Subfile.$FormatString

                $ReportObjects = @{}

                [hashtable]$Params = $PSBoundParameters
                $Params['TargetPath'] = $File.Path
                $Params['NetworkPath'] = $File.NetworkPaths
                $HtmlElements = Get-HtmlReportElements @Params

                $BodyParams = @{
                    HtmlFolderPermissions = $Permissions.Div
                    HtmlExclusions        = $HtmlElements.ExclusionsDiv
                    HtmlFileList          = $HtmlElements.HtmlDivOfFiles
                    ReportFooter          = $HtmlElements.ReportFooter
                    SummaryDivHeader      = $HtmlElements.SummaryDivHeader
                    DetailDivHeader       = $HtmlElements.DetailDivHeader
                    NetworkPathDiv        = $HtmlElements.NetworkPathDiv
                }

                ForEach ($Level in $SplitDetail) {

                    # Save the report
                    $ReportObjects[$Level] = Invoke-Command -ScriptBlock $DetailScripts[$Level]

                }

                switch ($Format) {

                    'csv' {

                        Out-PermissionDetailReport -Detail $SplitDetail -ReportObject $ReportObjects -DetailExport $DetailExports -Format $Format -OutputDir $FormatDir -Culture $Culture -DetailString $DetailStrings

                    }

                    'html' {

                        Out-PermissionDetailReport -Detail $SplitDetail -ReportObject $ReportObjects -DetailExport $DetailExports -Format $Format -OutputDir $FormatDir -FileName $FileName -Culture $Culture -DetailString $DetailStrings

                    }

                    'js' {

                        Out-PermissionDetailReport -Detail $SplitDetail -ReportObject $ReportObjects -DetailExport $DetailExports -Format $Format -OutputDir $FormatDir -FileName $FileName -Culture $Culture -DetailString $DetailStrings

                    }

                    'prtgxml' {

                        # Output the full path of the XML file (result of the custom XML sensor for Paessler PRTG Network Monitor) to the Information stream
                        #Write-Information $XmlFile

                        # Save the XML file to disk
                        #$null = Set-Content -LiteralPath $XmlFile -Value $XMLOutput

                    }

                    'xml' {}

                }

            }

        }

    }

}
function Remove-CachedCimSession {

    param (

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{}))

    )

    ForEach ($CacheResult in $CimCache.Values) {

        if ($CacheResult) {

            $CimSession = $CacheResult['CimSession']

            if ($CimSession) {
                $null = Remove-CimSession -CimSession $CimSession
            }

        }

    }

}
function Resolve-AccessControlList {

    # Wrapper to multithread Resolve-Acl
    # Resolve identities in access control lists to their SIDs and NTAccount names

    param (

        # Cache of access control lists keyed by path
        [hashtable]$ACLsByPath = [hashtable]::Synchronized(@{}),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        # Maximum number of concurrent threads to allow
        [int]$ThreadCount = (Get-CimInstance -ClassName CIM_Processor | Measure-Object -Sum -Property NumberOfLogicalProcessors).Sum,

        # Cache of access control entries keyed by GUID generated in this function
        [hashtable]$ACEsByGUID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entry GUIDs keyed by their resolved identities
        [hashtable]$AceGUIDsByResolvedID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entry GUIDs keyed by their paths
        [hashtable]$AceGUIDsByPath = ([hashtable]::Synchronized(@{})),

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        <#
        Dictionary to cache directory entries to avoid redundant lookups
 
        Defaults to an empty thread-safe hashtable
        #>

        [hashtable]$DirectoryEntryCache = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain DNS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName,AdsiProvider,Win32Accounts properties as values
        [hashtable]$DomainsByFqdn = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain NetBIOS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByNetbios = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain SIDs as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsBySid = ([hashtable]::Synchronized(@{})),

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # ID of the parent progress bar under which to show progres
        [int]$ProgressParentId,

        # String translations indexed by value in the [System.Security.AccessControl.InheritanceFlags] enum
        # Parameter default value is on a single line as a workaround to a PlatyPS bug
        [string[]]$InheritanceFlagResolved = @('this folder but not subfolders', 'this folder and subfolders', 'this folder and files, but not subfolders', 'this folder, subfolders, and files')

    )

    $Progress = @{
        Activity = 'Resolve-AccessControlList'
    }
    if ($PSBoundParameters.ContainsKey('ProgressParentId')) {
        $Progress['ParentId'] = $ProgressParentId
        $Progress['Id'] = $ProgressParentId + 1
    } else {
        $Progress['Id'] = 0
    }

    $Paths = $ACLsByPath.Keys
    $Count = $Paths.Count
    Write-Progress @Progress -Status "0% (ACL 0 of $Count)" -CurrentOperation 'Initializing' -PercentComplete 0

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        WhoAmI       = $WhoAmI
    }

    $ACEPropertyName = (Get-Member -InputObject $ACLsByPath.Values.Access[0] -MemberType Property, CodeProperty, ScriptProperty, NoteProperty).Name

    $ResolveAclParams = @{
        DirectoryEntryCache     = $DirectoryEntryCache
        DomainsBySID            = $DomainsBySID
        DomainsByNetbios        = $DomainsByNetbios
        DomainsByFqdn           = $DomainsByFqdn
        ThisHostName            = $ThisHostName
        ThisFqdn                = $ThisFqdn
        WhoAmI                  = $WhoAmI
        LogMsgCache             = $LogMsgCache
        CimCache                = $CimCache
        ACEsByGuid              = $ACEsByGUID
        AceGUIDsByPath          = $AceGUIDsByPath
        AceGUIDsByResolvedID    = $AceGUIDsByResolvedID
        ACLsByPath              = $ACLsByPath
        ACEPropertyName         = $ACEPropertyName
        InheritanceFlagResolved = $InheritanceFlagResolved
    }

    if ($ThreadCount -eq 1) {

        [int]$ProgressInterval = [math]::max(($Count / 100), 1)
        $IntervalCounter = 0
        $i = 0

        ForEach ($ThisPath in $Paths) {

            $IntervalCounter++

            if ($IntervalCounter -eq $ProgressInterval) {

                [int]$PercentComplete = $i / $Count * 100
                Write-Progress @Progress -Status "$PercentComplete% (ACL $($i + 1) of $Count) Resolve-Acl" -CurrentOperation $ThisPath -PercentComplete $PercentComplete
                $IntervalCounter = 0

            }

            $i++ # increment $i after Write-Progress to show progress conservatively rather than optimistically
            Write-LogMsg @LogParams -Text "Resolve-Acl -InputObject '$ThisPath' -ACLsByPath `$ACLsByPath -ACEsByGUID `$ACEsByGUID"
            Resolve-Acl -ItemPath $ThisPath @ResolveAclParams

        }

    } else {

        $SplitThreadParams = @{
            Command        = 'Resolve-Acl'
            InputObject    = $Paths
            InputParameter = 'ItemPath'
            TodaysHostname = $ThisHostname
            WhoAmI         = $WhoAmI
            LogMsgCache    = $LogMsgCache
            Threads        = $ThreadCount
            AddParam       = $ResolveAclParams
            #DebugOutputStream = 'Debug'
        }

        Write-LogMsg @LogParams -Text "Split-Thread -Command 'Resolve-Acl' -InputParameter InputObject -InputObject @('$($ACLsByPath.Keys -join "','")') -AddParam @{ACLsByPath=`$ACLsByPath;ACEsByGUID=`$ACEsByGUID}"
        Split-Thread @SplitThreadParams

    }

    Write-Progress @Progress -Completed

}
function Resolve-Ace {
    <#
    .SYNOPSIS
    Use ADSI to lookup info about IdentityReferences from Authorization Rule Collections that came from Discretionary Access Control Lists
    .DESCRIPTION
    Based on the IdentityReference proprety of each Access Control Entry:
    Resolve SID to NT account name and vise-versa
    Resolve well-known SIDs
    Resolve generic defaults like 'NT AUTHORITY' and 'BUILTIN' to the applicable computer or domain name
    Add these properties (IdentityReferenceSID,IdentityReferenceResolved) to the object and return it
    .INPUTS
    [System.Security.AccessControl.AuthorizationRuleCollection]$ACE
    .OUTPUTS
    [PSCustomObject] Original object plus IdentityReferenceSID,IdentityReferenceResolved, and AdsiProvider properties
    .EXAMPLE
    Get-Acl |
    Expand-Acl |
    Resolve-Ace
 
    Use Get-Acl from the Microsoft.PowerShell.Security module as the source of the access list
    This works in either Windows Powershell or in Powershell
    Get-Acl does not support long paths (>256 characters)
    That was why I originally used the .Net Framework method
    .EXAMPLE
    Get-FolderAce -LiteralPath C:\Test -IncludeInherited |
    Resolve-Ace
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    $Sections = [System.Security.AccessControl.AccessControlSections]::Access -bor [System.Security.AccessControl.AccessControlSections]::Owner
    $FileSecurity = [System.Security.AccessControl.FileSecurity]::new($DirectoryInfo,$Sections)
    $IncludeExplicitRules = $true
    $IncludeInheritedRules = $true
    $AccountType = [System.Security.Principal.SecurityIdentifier]
    $FileSecurity.GetAccessRules($IncludeExplicitRules,$IncludeInheritedRules,$AccountType) |
    Resolve-Ace
 
    This uses .Net Core as the source of the access list
    It uses the GetAccessRules method on the [System.Security.AccessControl.FileSecurity] class
    The targetType parameter of the method is used to specify that the accounts in the ACL are returned as SIDs
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    $Sections = [System.Security.AccessControl.AccessControlSections]::Access -bor
    [System.Security.AccessControl.AccessControlSections]::Owner -bor
    [System.Security.AccessControl.AccessControlSections]::Group
    $DirectorySecurity = [System.Security.AccessControl.DirectorySecurity]::new($DirectoryInfo,$Sections)
    $IncludeExplicitRules = $true
    $IncludeInheritedRules = $true
    $AccountType = [System.Security.Principal.NTAccount]
    $FileSecurity.GetAccessRules($IncludeExplicitRules,$IncludeInheritedRules,$AccountType) |
    Resolve-Ace
 
    This uses .Net Core as the source of the access list
    It uses the GetAccessRules method on the [System.Security.AccessControl.FileSecurity] class
    The targetType parameter of the method is used to specify that the accounts in the ACL are returned as NT account names (DOMAIN\User)
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    [System.Security.AccessControl.DirectorySecurity]$DirectorySecurity = $DirectoryInfo.GetAccessControl('Access')
    [System.Security.AccessControl.AuthorizationRuleCollection]$AuthRules = $DirectorySecurity.Access
    $AuthRules | Resolve-Ace
 
    Use the .Net Framework (or legacy .Net Core up to 2.2) as the source of the access list
    Only works in Windows PowerShell
    Those versions of .Net had a GetAccessControl method on the [System.IO.DirectoryInfo] class
    This method is removed in modern versions of .Net Core
 
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    $Sections = [System.Security.AccessControl.AccessControlSections]::Access -bor [System.Security.AccessControl.AccessControlSections]::Owner
    $FileSecurity = [System.IO.FileSystemAclExtensions]::GetAccessControl($DirectoryInfo,$Sections)
 
    The [System.IO.FileSystemAclExtensions] class is a Windows-specific implementation
    It provides no known benefit over the cross-platform equivalent [System.Security.AccessControl.FileSecurity]
 
    .NOTES
    Dependencies:
        Get-DirectoryEntry
        Add-SidInfo
        Get-TrustedDomain
        Find-AdsiProvider
 
    if ($FolderPath.Length -gt 255) {
        $FolderPath = "\\?\$FolderPath"
    }
#>

    [OutputType([void])]
    param (

        # Authorization Rule Collection of Access Control Entries from Discretionary Access Control Lists
        [Parameter(
            ValueFromPipeline
        )]
        [object]$ACE,

        # Cache of access control lists keyed by path
        [hashtable]$ACLsByPath = [hashtable]::Synchronized(@{}),

        [Parameter(
            ValueFromPipeline
        )]
        [object]$ItemPath,

        # Cache of access control entries keyed by GUID generated in this function
        [hashtable]$ACEsByGUID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entry GUIDs keyed by their resolved identities
        [hashtable]$AceGUIDsByResolvedID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entry GUIDs keyed by their paths
        [hashtable]$AceGUIDsByPath = ([hashtable]::Synchronized(@{})),

        <#
        Dictionary to cache directory entries to avoid redundant lookups
 
        Defaults to an empty thread-safe hashtable
        #>

        [hashtable]$DirectoryEntryCache = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain NetBIOS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByNetbios = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain SIDs as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsBySid = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain DNS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByFqdn = ([hashtable]::Synchronized(@{})),

        <#
    Hostname of the computer running this function.
 
    Can be provided as a string to avoid calls to HOSTNAME.EXE
    #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
    FQDN of the computer running this function.
 
    Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
    #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        [string[]]$ACEPropertyName = (Get-Member -InputObject $ACE -MemberType Property, CodeProperty, ScriptProperty, NoteProperty).Name,

        # Will be set as the Source property of the output object.
        # Intended to reflect permissions resulting from Ownership rather than Discretionary Access Lists
        [string]$Source,

        # String translations indexed by value in the [System.Security.AccessControl.InheritanceFlags] enum
        # Parameter default value is on a single line as a workaround to a PlatyPS bug
        [string[]]$InheritanceFlagResolved = @('this folder but not subfolders', 'this folder and subfolders', 'this folder and files, but not subfolders', 'this folder, subfolders, and files')

    )

    $LogParams = @{
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        LogMsgCache  = $LogMsgCache
        WhoAmI       = $WhoAmI
    }

    $Log = @{
        ThisHostname = $ThisHostname
        LogMsgCache  = $LogMsgCache
        WhoAmI       = $WhoAmI
    }

    $Cache1 = @{
        DirectoryEntryCache = $DirectoryEntryCache
        DomainsByFqdn       = $DomainsByFqdn
    }

    $Cache2 = @{
        DomainsByNetBIOS = $DomainsByNetbios
        DomainsBySid     = $DomainsBySid
        CimCache         = $CimCache
    }

    Write-LogMsg @LogParams -Text "Resolve-IdentityReferenceDomainDNS -IdentityReference '$($ACE.IdentityReference)' -ItemPath '$ItemPath' -ThisFqdn '$ThisFqdn' @Cache2 @Log"
    $DomainDNS = Resolve-IdentityReferenceDomainDNS -IdentityReference $ACE.IdentityReference -ItemPath $ItemPath -ThisFqdn $ThisFqdn @Cache2 @Log

    Write-LogMsg @LogParams -Text "`$AdsiServer = Get-AdsiServer -Fqdn '$DomainDNS' -ThisFqdn '$ThisFqdn'"
    $AdsiServer = Get-AdsiServer -Fqdn $DomainDNS -ThisFqdn $ThisFqdn @GetAdsiServerParams @Cache1 @Cache2 @Log

    Write-LogMsg @LogParams -Text "Resolve-IdentityReference -IdentityReference '$($ACE.IdentityReference)' -AdsiServer `$AdsiServer -ThisFqdn '$ThisFqdn' # ADSI server '$($AdsiServer.AdsiProvider)://$($AdsiServer.Dns)'"
    $ResolvedIdentityReference = Resolve-IdentityReference -IdentityReference $ACE.IdentityReference -AdsiServer $AdsiServer -ThisFqdn $ThisFqdn @Cache1 @Cache2 @Log

    # TODO: add a param to offer DNS instead of or in addition to NetBIOS

    $ObjectProperties = @{
        Access                    = "$($ACE.AccessControlType) $($ACE.FileSystemRights) $($InheritanceFlagResolved[$ACE.InheritanceFlags])"
        AdsiProvider              = $AdsiServer.AdsiProvider
        AdsiServer                = $AdsiServer.Dns
        IdentityReferenceSID      = $ResolvedIdentityReference.SIDString
        IdentityReferenceResolved = $ResolvedIdentityReference.IdentityReferenceNetBios
        Path                      = $ItemPath
        SourceOfAccess            = $Source
        PSTypeName                = 'Permission.AccessControlEntry'
    }

    ForEach ($ThisProperty in $ACEPropertyName) {
        $ObjectProperties[$ThisProperty] = $ACE.$ThisProperty
    }

    $OutputObject = [PSCustomObject]$ObjectProperties
    $Guid = [guid]::NewGuid()
    Add-CacheItem -Cache $ACEsByGUID -Key $Guid -Value $OutputObject -Type ([object])
    $Type = [guid]
    Add-CacheItem -Cache $AceGUIDsByResolvedID -Key $OutputObject.IdentityReferenceResolved -Value $Guid -Type $Type
    Add-CacheItem -Cache $AceGUIDsByPath -Key $OutputObject.Path -Value $Guid -Type $Type

}
function Resolve-Acl {
    <#
    .SYNOPSIS
    Use ADSI to lookup info about IdentityReferences from Authorization Rule Collections that came from Discretionary Access Control Lists
    .DESCRIPTION
    Based on the IdentityReference proprety of each Access Control Entry:
    Resolve SID to NT account name and vise-versa
    Resolve well-known SIDs
    Resolve generic defaults like 'NT AUTHORITY' and 'BUILTIN' to the applicable computer or domain name
    Add these properties (IdentityReferenceSID,IdentityReferenceName,IdentityReferenceResolved) to the object and return it
    .INPUTS
    [System.Security.AccessControl.AuthorizationRuleCollection]$ItemPath
    .OUTPUTS
    [PSCustomObject] Original object plus IdentityReferenceSID,IdentityReferenceName,IdentityReferenceResolved, and AdsiProvider properties
    .EXAMPLE
    Get-Acl |
    Expand-Acl |
    Resolve-Ace
 
    Use Get-Acl from the Microsoft.PowerShell.Security module as the source of the access list
    This works in either Windows Powershell or in Powershell
    Get-Acl does not support long paths (>256 characters)
    That was why I originally used the .Net Framework method
    .EXAMPLE
    Get-FolderAce -LiteralPath C:\Test -IncludeInherited |
    Resolve-Ace
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    $Sections = [System.Security.AccessControl.AccessControlSections]::Access -bor [System.Security.AccessControl.AccessControlSections]::Owner
    $FileSecurity = [System.Security.AccessControl.FileSecurity]::new($DirectoryInfo,$Sections)
    $IncludeExplicitRules = $true
    $IncludeInheritedRules = $true
    $AccountType = [System.Security.Principal.SecurityIdentifier]
    $FileSecurity.GetAccessRules($IncludeExplicitRules,$IncludeInheritedRules,$AccountType) |
    Resolve-Ace
 
    This uses .Net Core as the source of the access list
    It uses the GetAccessRules method on the [System.Security.AccessControl.FileSecurity] class
    The targetType parameter of the method is used to specify that the accounts in the ACL are returned as SIDs
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    $Sections = [System.Security.AccessControl.AccessControlSections]::Access -bor
    [System.Security.AccessControl.AccessControlSections]::Owner -bor
    [System.Security.AccessControl.AccessControlSections]::Group
    $DirectorySecurity = [System.Security.AccessControl.DirectorySecurity]::new($DirectoryInfo,$Sections)
    $IncludeExplicitRules = $true
    $IncludeInheritedRules = $true
    $AccountType = [System.Security.Principal.NTAccount]
    $FileSecurity.GetAccessRules($IncludeExplicitRules,$IncludeInheritedRules,$AccountType) |
    Resolve-Ace
 
    This uses .Net Core as the source of the access list
    It uses the GetAccessRules method on the [System.Security.AccessControl.FileSecurity] class
    The targetType parameter of the method is used to specify that the accounts in the ACL are returned as NT account names (DOMAIN\User)
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    [System.Security.AccessControl.DirectorySecurity]$DirectorySecurity = $DirectoryInfo.GetAccessControl('Access')
    [System.Security.AccessControl.AuthorizationRuleCollection]$AuthRules = $DirectorySecurity.Access
    $AuthRules | Resolve-Ace
 
    Use the .Net Framework (or legacy .Net Core up to 2.2) as the source of the access list
    Only works in Windows PowerShell
    Those versions of .Net had a GetAccessControl method on the [System.IO.DirectoryInfo] class
    This method is removed in modern versions of .Net Core
 
    .EXAMPLE
    [System.String]$FolderPath = 'C:\Test'
    [System.IO.DirectoryInfo]$DirectoryInfo = Get-Item -LiteralPath $FolderPath
    $Sections = [System.Security.AccessControl.AccessControlSections]::Access -bor [System.Security.AccessControl.AccessControlSections]::Owner
    $FileSecurity = [System.IO.FileSystemAclExtensions]::GetAccessControl($DirectoryInfo,$Sections)
 
    The [System.IO.FileSystemAclExtensions] class is a Windows-specific implementation
    It provides no known benefit over the cross-platform equivalent [System.Security.AccessControl.FileSecurity]
 
    .NOTES
    Dependencies:
        Get-DirectoryEntry
        Add-SidInfo
        Get-TrustedDomain
        Find-AdsiProvider
 
    if ($FolderPath.Length -gt 255) {
        $FolderPath = "\\?\$FolderPath"
    }
#>

    [OutputType([PSCustomObject])]
    param (

        # Authorization Rule Collection of Access Control Entries from Discretionary Access Control Lists
        [Parameter(
            ValueFromPipeline
        )]
        [object]$ItemPath,

        # Cache of access control lists keyed by path
        [hashtable]$ACLsByPath = [hashtable]::Synchronized(@{}),

        # Cache of access control entries keyed by GUID generated in this function
        [hashtable]$ACEsByGUID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entry GUIDs keyed by their resolved identities
        [hashtable]$AceGUIDsByResolvedID = ([hashtable]::Synchronized(@{})),

        # Cache of access control entry GUIDs keyed by their paths
        [hashtable]$AceGUIDsByPath = ([hashtable]::Synchronized(@{})),

        <#
        Dictionary to cache directory entries to avoid redundant lookups
 
        Defaults to an empty thread-safe hashtable
        #>

        [hashtable]$DirectoryEntryCache = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain NetBIOS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByNetbios = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain SIDs as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsBySid = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain DNS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByFqdn = ([hashtable]::Synchronized(@{})),

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        [string[]]$ACEPropertyName = (Get-Member -InputObject $ItemPath -MemberType Property, CodeProperty, ScriptProperty, NoteProperty).Name,

        # String translations indexed by value in the [System.Security.AccessControl.InheritanceFlags] enum
        # Parameter default value is on a single line as a workaround to a PlatyPS bug
        [string[]]$InheritanceFlagResolved = @('this folder but not subfolders', 'this folder and subfolders', 'this folder and files, but not subfolders', 'this folder, subfolders, and files')

    )

    $LogParams = @{
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        LogMsgCache  = $LogMsgCache
        WhoAmI       = $WhoAmI
    }

    $ACL = $ACLsByPath[$ItemPath]

    if ($ACL.Owner.IdentityReference) {
        Write-LogMsg -Text "Resolve-Ace -ACE $($ACL.Owner) -ACEPropertyName @('$($ACEPropertyName -join "','")') @PSBoundParameters" @LogParams
        Resolve-Ace -ACE $ACL.Owner -Source 'Ownership' @PSBoundParameters
    }

    ForEach ($ACE in $ACL.Access) {
        Write-LogMsg -Text "Resolve-Ace -ACE $ACE -ACEPropertyName @('$($ACEPropertyName -join "','")') @PSBoundParameters" @LogParams
        Resolve-Ace -ACE $ACE -Source 'Discretionary ACL' @PSBoundParameters
    }

}
function Resolve-Folder {

    # Resolve the provided FolderPath to all of its associated UNC paths, including all DFS folder targets

    param (

        # Path of the folder(s) to resolve to all their associated UNC paths
        [string]$TargetPath,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        # Hostname to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$ThisHostname = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Hashtable of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages
    )

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        Type         = $DebugOutputstream
        WhoAmI       = $WhoAmI
    }

    $LoggingParams = @{
        LogMsgCache       = $LogMsgCache
        ThisHostname      = $ThisHostname
        DebugOutputStream = $DebugOutputStream
        WhoAmI            = $WhoAmI
    }

    $RegEx = '^(?<DriveLetter>\w):'

    if ($TargetPath -match $RegEx) {

        Write-LogMsg @LogParams -Text "Get-CachedCimInstance -ComputerName $ThisHostname -ClassName Win32_MappedLogicalDisk"
        $MappedNetworkDrives = Get-CachedCimInstance -ComputerName $ThisHostname -ClassName Win32_MappedLogicalDisk -KeyProperty DeviceID -CimCache $CimCache -ThisFqdn $ThisFqdn @LoggingParams

        $MatchingNetworkDrive = $MappedNetworkDrives |
        Where-Object -FilterScript { $_.DeviceID -eq "$($Matches.DriveLetter):" }

        if ($MatchingNetworkDrive) {
            # Resolve mapped network drives to their UNC path
            $UNC = $MatchingNetworkDrive.ProviderName
        } else {
            # Resolve local drive letters to their UNC paths using administrative shares
            $UNC = $TargetPath -replace $RegEx, "\\$(hostname)\$($Matches.DriveLetter)$"
        }

        if ($UNC) {
            # Replace hostname with FQDN in the path
            $Server = $UNC.split('\')[2]
            $FQDN = ConvertTo-DnsFqdn -ComputerName $Server
            $UNC -replace "^\\\\$Server\\", "\\$FQDN\"
        }

    } else {

        ## Workaround in place: Get-NetDfsEnum -Verbose parameter is not used due to errors when it is used with the PsRunspace module for multithreading
        ## https://github.com/IMJLA/Export-Permission/issues/46
        ## https://github.com/IMJLA/PsNtfs/issues/1
        Write-LogMsg @LogParams -Text "Get-NetDfsEnum -FolderPath '$TargetPath'"
        $AllDfs = Get-NetDfsEnum -FolderPath $TargetPath -ErrorAction SilentlyContinue

        if ($AllDfs) {

            $MatchingDfsEntryPaths = $AllDfs |
            Group-Object -Property DfsEntryPath |
            Where-Object -FilterScript {
                $TargetPath -match [regex]::Escape($_.Name)
            }

            # Filter out the DFS Namespace
            # TODO: I know this is an inefficient n2 algorithm, but my brain is fried...plez...halp...leeloo dallas multipass
            $RemainingDfsEntryPaths = $MatchingDfsEntryPaths |
            Where-Object -FilterScript {
                -not [bool]$(
                    ForEach ($ThisEntryPath in $MatchingDfsEntryPaths) {
                        if ($ThisEntryPath.Name -match "$([regex]::Escape("$($_.Name)")).+") { $true }
                    }
                )
            } |
            Sort-Object -Property Name

            $RemainingDfsEntryPaths |
            Select-Object -Last 1 -ExpandProperty Group |
            ForEach-Object {
                $_.FullOriginalQueryPath -replace [regex]::Escape($_.DfsEntryPath), $_.DfsTarget
            }

        } else {

            $Server = $TargetPath.split('\')[2]
            $FQDN = ConvertTo-DnsFqdn -ComputerName $Server
            $TargetPath -replace "^\\\\$Server\\", "\\$FQDN\"

        }

    }

}
function Resolve-FormatParameter {
    param (

        # File formats to export
        [ValidateSet('csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string[]]$FileFormat = @('csv', 'html', 'js', 'json', 'prtgxml', 'xml'),

        # Type of output returned to the output stream
        [ValidateSet('passthru', 'none', 'csv', 'html', 'js', 'json', 'prtgxml', 'xml')]
        [string]$OutputFormat = 'passthru'

    )

    $AllFormats = @{}

    ForEach ($Format in $FileFormat) {
        $AllFormats[$Format] = $null
    }

    if ($OutputFormat -ne 'passthru' -and $OutputFormat -ne 'none') {
        $AllFormats[$OutputFormat] = $null
    }

    return [string[]]$AllFormats.Keys

}
function Resolve-IdentityReferenceDomainDNS {

    param (

        [string]$IdentityReference,

        [object]$ItemPath,

        # Hashtable with known domain NetBIOS names as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsByNetbios = ([hashtable]::Synchronized(@{})),

        # Hashtable with known domain SIDs as keys and objects with Dns,NetBIOS,SID,DistinguishedName properties as values
        [hashtable]$DomainsBySid = ([hashtable]::Synchronized(@{})),

        <#
        Hostname of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE
        #>

        [string]$ThisHostName = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{}))

    )

    $LogParams = @{
        ThisHostname = $ThisHostname
        Type         = $DebugOutputStream
        LogMsgCache  = $LogMsgCache
        WhoAmI       = $WhoAmI
    }

    switch -Wildcard ($IdentityReference) {

        "S-1-*" {
            # IdentityReference is a SID (Revision 1)
            $IndexOfLastHyphen = $IdentityReference.LastIndexOf("-")
            $DomainSid = $IdentityReference.Substring(0, $IndexOfLastHyphen)
            if ($DomainSid) {
                $DomainCacheResult = $DomainsBySID[$DomainSid]
                if ($DomainCacheResult) {
                    Write-LogMsg @LogParams -Text " # Domain SID cache hit for '$DomainSid' for '$IdentityReference'"
                    $DomainDNS = $DomainCacheResult.Dns
                } else {
                    Write-LogMsg @LogParams -Text " # Domain SID cache miss for '$DomainSid' for '$IdentityReference'"
                }
            }
        }
        "NT SERVICE\*" {}
        "BUILTIN\*" {}
        "NT AUTHORITY\*" {}
        default {
            $DomainNetBIOS = ($IdentityReference -split '\\')[0]
            if ($DomainNetBIOS) {
                $DomainDNS = $DomainsByNetbios[$DomainNetBIOS].Dns #Doesn't work for BUILTIN, etc.
            }
            if (-not $DomainDNS) {
                $ThisServerDn = ConvertTo-DistinguishedName -Domain $DomainNetBIOS -DomainsByNetbios $DomainsByNetbios @LoggingParams
                $DomainDNS = ConvertTo-Fqdn -DistinguishedName $ThisServerDn -ThisFqdn $ThisFqdn -CimCache $CimCache @LoggingParams
            }
        }
    }

    if (-not $DomainDNS) {
        # TODO - Bug: I think this will report incorrectly for a remote domain not in the cache (trust broken or something)
        Write-LogMsg @LogParams -Text "Find-ServerNameInPath -LiteralPath '$ItemPath' -ThisFqdn '$ThisFqdn'"
        $DomainDNS = Find-ServerNameInPath -LiteralPath $ItemPath -ThisFqdn $ThisFqdn
    }

    return $DomainDNS

}
function Resolve-PermissionTarget {

    # Resolve each target path to all of its associated UNC paths (including all DFS folder targets)

    param (

        # Path to the NTFS folder whose permissions to export
        [Parameter(ValueFromPipeline)]
        [ValidateScript({ Test-Path $_ })]
        [System.IO.DirectoryInfo[]]$TargetPath,

        # Cache of CIM sessions and instances to reduce connections and queries
        [hashtable]$CimCache = ([hashtable]::Synchronized(@{})),

        # Output stream to send the log messages to
        [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)]
        [string]$DebugOutputStream = 'Debug',

        # Hostname to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$ThisHostname = (HOSTNAME.EXE),

        <#
        FQDN of the computer running this function.
 
        Can be provided as a string to avoid calls to HOSTNAME.EXE and [System.Net.Dns]::GetHostByName()
        #>

        [string]$ThisFqdn = ([System.Net.Dns]::GetHostByName((HOSTNAME.EXE)).HostName),

        # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process)
        [string]$WhoAmI = (whoami.EXE),

        # Hashtable of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided)
        [hashtable]$LogMsgCache = $Global:LogMessages,

        [hashtable]$Output = [hashtable]::Synchronized(@{})

    )

    $LogParams = @{
        LogMsgCache  = $LogMsgCache
        ThisHostname = $ThisHostname
        Type         = $DebugOutputstream
        WhoAmI       = $WhoAmI
    }

    $ResolveFolderParams = @{
        LogMsgCache       = $LogMsgCache
        ThisHostname      = $ThisHostname
        DebugOutputStream = $DebugOutputStream
        WhoAmI            = $WhoAmI
        CimCache          = $CimCache
        ThisFqdn          = $ThisFqdn
    }

    ForEach ($ThisTargetPath in $TargetPath) {

        Write-LogMsg @LogParams -Text "Resolve-Folder -TargetPath '$ThisTargetPath'"
        $Output[$ThisTargetPath] = Resolve-Folder -TargetPath $ThisTargetPath @ResolveFolderParams

    }

}
function Select-UniquePrincipal {

    param (

        # Cache of security principals keyed by resolved identity reference
        [hashtable]$PrincipalsByResolvedID = ([hashtable]::Synchronized(@{})),

        # Regular expressions matching names of Users or Groups to exclude from the Html report
        [string[]]$ExcludeAccount,

        <#
        Domain(s) to ignore (they will be removed from the username)
 
        Intended when a user has matching SamAccountNames in multiple domains but you only want them to appear once on the report.
 
        Can also be used to remove all domains simply for brevity in the report.
        #>

        [string[]]$IgnoreDomain,

        # Hashtable will be used to deduplicate
        $UniquePrincipal = [hashtable]::Synchronized(@{}),

        $UniquePrincipalsByResolvedID = [hashtable]::Synchronized(@{})

    )

    $FilterContents = @{}

    ForEach ($ThisID in $PrincipalsByResolvedID.Keys) {

        if (
            # Exclude the objects whose names match the regular expressions specified in the parameters
            [bool]$(
                ForEach ($RegEx in $ExcludeAccount) {
                    if ($ThisID -match $RegEx) {
                        $FilterContents[$ThisID] = $ThisID
                        $true
                    }
                }
            )
        ) { continue }

        $ShortName = $ThisID

        ForEach ($IgnoreThisDomain in $IgnoreDomain) {
            $ShortName = $ShortName -replace "^$IgnoreThisDomain\\", ''
        }

        $ThisKnownUser = $null
        $ThisKnownUser = $UniquePrincipal[$ShortName]
        if ($null -eq $ThisKnownUser) {
            $UniquePrincipal[$ShortName] = [System.Collections.Generic.List[string]]::new()

        }

        $null = $UniquePrincipal[$ShortName].Add($ThisID)
        $UniquePrincipalsByResolvedID[$ThisID] = $ShortName

    }

}

# Add any custom C# classes as usable (exported) types
$CSharpFiles = Get-ChildItem -Path "$PSScriptRoot\*.cs"
ForEach ($ThisFile in $CSharpFiles) {
    Add-Type -Path $ThisFile.FullName -ErrorAction Stop
}

Export-ModuleMember -Function @('Add-CacheItem','ConvertTo-ItemBlock','Expand-Permission','Expand-PermissionTarget','Find-ResolvedIDsWithAccess','Find-ServerFqdn','Format-Permission','Format-TimeSpan','Get-AccessControlList','Get-CachedCimInstance','Get-CachedCimSession','Get-FolderPermissionsBlockUNUSED','Get-PermissionPrincipal','Get-PrtgXmlSensorOutput','Get-TimeZoneName','Initialize-Cache','Invoke-PermissionCommand','Out-PermissionReport','Remove-CachedCimSession','Resolve-AccessControlList','Resolve-Ace','Resolve-Acl','Resolve-Folder','Resolve-FormatParameter','Resolve-IdentityReferenceDomainDNS','Resolve-PermissionTarget','Select-UniquePrincipal')