eNLib.psm1

<#
.SYNOPSIS
    eN's support functions library.
.DESCRIPTION
    most commonly required functions such as better logging support for scripts, forking
    information to screen and file, enchanced GUI controls such as input box, most common
    connection accelerators.
.LINK
    https://w-files.pl
.NOTES
    nExoR ::))o-
    version 210219
    changes
        - 210219 load-CSV function added
        - 210212 wl fix
        - 210210 write-log and start-logging init fix
        - 210209 get-answerBox changes, get-valueFromInputBox, wl fix
        - 210206 write-log accepts all unnamed parameters as messages
        - 210205 write-log fixes
        - 210202 tuned write-log and start-logging, fixes and logical separation. v0.9
        - 201018 initialize
#>


#################################################### GENERAL
$logFile=''

function start-Logging {
    <#
    .SYNOPSIS
        initilizes log file under $logFile variable for write-log function.
    .DESCRIPTION
        all scripts require logging mechinism. write-log function forking each output to screen and to logfile
        is a very convinient way keeping all logs consistent with very nice host output.
        this function initilizeds $logFile variable creation, and initiates the log file itself. in order to
        ease the creation there are several ways of initilizing $logFile:
        - using write-log directly
            - from console host
            - from script
        - using this function directly
            - no parameters - defaults to $ScriptRoot/Logs folder
            - using 'useProfile' - to store logs in User Documents/Logs directory
            - using 'logFolder' parameter to define particular folder for logs
            - using 'logFileName' - (exclusive to logFolder) presenting full path for the log or logfile name
    .EXAMPLE
        write-log
 
        using write-log will inderctly call start-logging function and initializes the log file with generic name,
        saved in 'Logs' subfolder under script run path.
    .EXAMPLE
        start-Logging -logFileName c:\temp\myLogs\somelog.log
        write-log 'test message'
 
        initializes the log file as c:\temp\myLogs\somelog.log .
    .EXAMPLE
        start-Logging -logFileName somelog.log
        write-log 'test message'
 
        initializes the log file as .\somelog.log .
    .EXAMPLE
        start-Logging -logFolder c:\temp\myLogs
        write-log 'test message'
 
        initializes the log file under c:\temp\myLogs\ folder with generic name containing script name and date.
    .EXAMPLE
        start-Logging -userProfilePath
        write-log 'test message'
 
        initializes the log file in Logs subfolder uder user profile path
    .INPUTS
        None.
    .OUTPUTS
        log file under $logFile variable.
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210210
        changes:
            - 210210 removing recurrency to write-log (loop elimination)
            - 210205 fixes to logfilename initialization
            - 210203 added 'logFolder' and proper log initilization when called indirectly
            - 210127 v1
            - 201018 initialize
    #>

    [CmdletBinding(DefaultParameterSetName='FilePath')]
    param(
        # full name for custom log file.
        [Parameter(ParameterSetName='FilePath',mandatory=$false,position=0)]
            [string]$logFileName,
        #create log in profile folder rather than script run path
        [Parameter(ParameterSetName='userProfile',mandatory=$false,position=0)]
            [alias('useProfile')]
            [switch]$userProfilePath,
        #similar to logFileName, but takes folder only and log file name is generic.
        [Parameter(ParameterSetName='Folder',mandatory=$false,position=0)]
            [string]$logFolder
    )

    #write-host -ForegroundColor red ">>$($MyInvocation.PSCommandPath)<<"
    if( [string]::isNullOrEmpty($MyInvocation.PSCommandPath) ) { #if run from console - set the logfile name as 'console'
        $scriptBaseName = 'console'
        $script:lastScriptUsed = 'console'
    } elseif( $MyInvocation.PSCommandPath -match '\.psm1$' ) { #if run from inside module...
        if([string]::isNullOrEmpty($script:lastScriptUsed) ) {
            $scriptBaseName = 'console'
        } else {
            $scriptBaseName = $script:lastScriptUsed
        }
    } else { #regular run from the script - take a script basename as logfile name
        $scriptBaseName = ([System.IO.FileInfo]$($MyInvocation.PSCommandPath)).basename
        $script:lastScriptUsed = $scriptBaseName
    }
    switch($PSCmdlet.ParameterSetName) {
        'userProfile' {
            $logFolder = [Environment]::GetFolderPath("MyDocuments") + '\Logs'
            $global:logFile = "{0}\_{1}-{2}.log" -f $logFolder,$scriptBaseName,$(Get-Date -Format yyMMddHHmm)
        }
        'Folder' {
            $global:logFile = "{0}\_{1}-{2}.log" -f $logFolder,$scriptBaseName,$(Get-Date -Format yyMMddHHmm)
        }
        'filePath' {
            if($scriptBaseName -eq 'console') {
                $logFolder = [Environment]::GetFolderPath("MyDocuments") + '\Logs'
                $global:logFile = "{0}\_{1}-{2}.log" -f $logFolder,$scriptBaseName,$(Get-Date -Format yyMMddHHmm)   
            }elseif ( [string]::IsNullOrEmpty($logFileName) ) {          #by default 'filepath' is used and empty
                $logFolder="$($MyInvocation.PSScriptRoot)\Logs"
                $global:logFile = "{0}\_{1}-{2}.log" -f $logFolder,$scriptBaseName,$(Get-Date -Format yyMMddHHmm)   
            } else {
                #logfile can be: 1. file, 2. folder, 3. fullpath
                $logFolder = Split-Path $logFileName -Parent
                if([string]::isNullOrEmpty($logFolder) ) { #logfile name without full path, name only
                    if( [string]::isNullOrEmpty($MyInvocation.PSScriptRoot) ) { #run directly from console
                        $logFolder = [Environment]::GetFolderPath("MyDocuments") + '\Logs'
                    } else {
                        $logFolder = $MyInvocation.PSScriptRoot
                    }
                }
                $logFile = Split-Path $logFileName -Leaf
                if( test-path $logFile -PathType Container ) {
                    write-host "$logFileName seems to be an existing folder. use 'logFolder' parameter or change log name. quitting." -ForegroundColor Red
                    exit -1
                }
                $global:logFile = "$logFolder\$logFile"
            }
        }
        default {
            write-host -ForegroundColor Magenta 'very strange error'
            exit -666
        }
    }

    if(-not (test-path $logFolder) ) {
        try{ 
            New-Item -ItemType Directory -Path $logFolder -ErrorAction Stop|Out-Null
            write-host "$LogFolder created."
        } catch {
            write-error $_.exception
            exit -2
        }
    }
    "*logging initiated $(get-date) in $($global:logFile)"|Out-File $global:logFile -Append
    write-host "*logging initiated $(get-date) in $($global:logFile)"
    "*script parameters:"|Out-File $global:logFile -Append
    if($script:PSBoundParameters.count -gt 0) {
        $script:PSBoundParameters|Out-File $global:logFile -Append
    } else {
        "<none>"|Out-File $global:logFile -Append
    }
    "***************************************************"|Out-File $global:logFile -Append
}
function write-log {
    <#
    .SYNOPSIS
        replacement for write-host, forking information to a log file and screen.
    .DESCRIPTION
        automates forking of output on two different endpoints - on the host, using write-host
        and to the file, appening its content.
        write-log converts everything to a string, so you can use it for virtually any type of
        variable. additionaly it adds timestamp, message type header and color (on host).
 
        information is written to a $logFile - you must initialize the value with 'start-Logging'
        or configure it manually.
 
        in order to use write-log, $logFile variable requires to be set up. this is during initialization
        by start-logging. by default logs are stored in $PSScriptRoot/Logs directory with generic file
        name. if you need special location refer to start-logging help how to initialize variable.
 
        function may also be used from command line - in this scenario log file will be created in
        Logs directory under User Documents folder. file with be named 'console-<date>.log'.
 
    .EXAMPLE
        write-log "all is fine"
 
        output 'all is fine' on the screen and to the log file.
    .EXAMPLE
        write-log all is fine
 
        outputs
            all
            is
            fine
        on the screen and to the log file - all unnamed parameters are displayed
    .EXAMPLE
        write-log -message "trees are green" -type ok
 
        shows 'trees are green' in Green colour, and send text to a log file.
    .EXAMPLE
        $someObject=get-process
        write-log -message $someObject -type info -noTimestamp -silent
 
        outputs processes object to the log file as -silent disables screen output. it will lack
        timestamp in a message header but will contain '[INFO]' block.
    .INPUTS
        None.
    .OUTPUTS
        text log file under $logFile
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210212
        changes:
            - 210212 imporper name when calling from console thru module
            - 210210 v2. init finally works!
            - 210209 when initialized on console, wl was not creating script log and using console file.
            - 210209 init from console fix
            - 210206 valueFromRemainingArguments
            - 210205 fix when run directly from console, init fixes
            - 210203 properly initiating log with new start-logging, when called indirectly
            - 210127 v1
            - 201018 initialize
 
        #TO|DO
        - colouring codes for text - change screen text colour on ** <y></y> <r></r> <g></g>
    #>

    
    param(
        #message to display - can be an object
        [parameter(ValueFromRemainingArguments=$true,mandatory=$false,position=0)]
            $message,
        #adds description and colour dependently on message type
            [string][validateSet('error','info','warning','ok')]$type,
        #do not output to a screen - logfile only
            [switch]$silent,
        # do not show timestamp with the message
            [switch]$skipTimestamp
    )

    $callStack = (Get-PSCallStack |Where-Object ScriptName)[-1]
    if( [string]::isNullOrEmpty($MyInvocation.PSCommandPath) ) { #it's run directly from console.
        $scriptBaseName = 'console'
        $logFolder = [Environment]::GetFolderPath("MyDocuments") + '\Logs'
    } elseif( -not [string]::isNullOrEmpty( $callStack ) ){ 
        if( $callStack.ScriptName -match '\.psm1$' ) { #run from inside module
            $logFolder = [Environment]::GetFolderPath("MyDocuments") + '\Logs'
            $scriptBaseName = 'console'
        } else {
            $logFolder = "$(split-path $callStack.scriptname -Parent)\Logs"
            $scriptBaseName = ([System.IO.FileInfo]$callStack.scriptname).basename
        }
    } else {
        $scriptBaseName = ([System.IO.FileInfo]$($MyInvocation.PSCommandPath)).basename 
        $logFolder = "$($MyInvocation.PSScriptRoot)\Logs"
    }
    if( [string]::isNullOrEmpty($global:logFile) -or ( $script:lastScriptUsed -ne $scriptbasename) ) {   
        $script:lastScriptUsed = $scriptBaseName
        $logFileName = "{0}\_{1}-{2}.log" -f $logFolder,$scriptBaseName,$(Get-Date -Format yyMMddHHmm)
        start-Logging -logFileName $logFileName
    }

    #ensure that whatever the type is - array, object.. - it will be output as string, add runtime
    if($null -eq $message) {$message=''}
    $message=($message|out-String).trim() 

    try {
        $finalMessageString=@()
        if(-not $skipTimestamp) {
            $finalMessageString += "$(Get-Date -Format "hh:mm:ss>") "
        }
        if(-not [string]::IsNullOrEmpty( $type) ) { 
            $finalMessageString += $type.ToUpper()+": " 
        }
        $finalMessageString += $message
        $message=$finalMessageString -join ''
        Add-Content -Path $global:logFile -Value $message
        if(-not $silent) {
            switch($type) {
                'error' {
                    write-host -ForegroundColor Red $message
                }
                'info' {
                    Write-Host -ForegroundColor DarkGray $message
                }
                'warning' {
                    Write-Host -ForegroundColor Yellow $message
                }
                'ok' {
                    Write-Host -ForegroundColor Green $message
                }
                default {
                    Write-Host $message 
                }
            }
        }
    } catch {
        Write-Error 'not able to write to log. suggest to cancel the script run.'
        $_.exception
    }      
}
function load-CSV {
    <#
    .SYNOPSIS
        loads CSV file with header check.
    .DESCRIPTION
        support function to gather data from CSV file with ability to ensure it is correct CSV file by
        enumerating header.
        with non-critical header function allows to add missing columns.
    .EXAMPLE
        $inputCSV = "c:\temp\mydata.csv"
        $header=@('column1','column2')
        $data = load-CSV -header $header -headerIsCritical -delimiter ';' -inputCSV $inputCSV
         
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210219
            last changes
            - 210219 initialized
     
        #TO|DO
        - automatic delimiter detection
        - add nonCritical header + crit header handling
    #>


    param(
        #path to CSV file containing data
        [parameter(mandatory=$true,position=0)]
            [string]$inputCSV,
        #expected header
        [parameter(mandatory=$true,position=1)]
            [string[]]$header,
        #this flag causes exit on load if any column is missing.
        [parameter(mandatory=$false,position=2)]
            [switch]$headerIsCritical,
        #CSV delimiter if different then regional settings
        [parameter(mandatory=$false,position=3)]
            [string]$delimiter=','
    )

    if(-not (test-path $inputCSV) ) {
        write-log "$inputCSV not found." -type error
        exit -1
    }

    try {
        $CSVData=import-csv -path "$inputCSV" -delimiter $delimiter -Encoding UTF8
    } catch {
        Write-log "not able to open $inputCSV. quitting." -type error 
        exit -2
    }

    $csvHeader=$CSVData|get-Member -MemberType NoteProperty|select-object -ExpandProperty Name
    $hmiss=@()
    foreach($el in $header) {
        if($csvHeader -notcontains $el) {
            Write-log """$el"" column missing in imported csv" -type warning
            $hmiss+=$el
        }
    }
    if($hmiss) {
        if($headerIsCritical) {
            Write-log "Wrong CSV header. check delimiter used. quitting." -type error
            exit -2
        }
        $ans=Read-Host -Prompt "some columns are missing. type 'add' to add them, 'c' to continue or anything else to cancel"
        switch($ans) {
            'add' {
                foreach($newCol in $hmiss) {
                    $CSVData|add-member  -MemberType NoteProperty -Name $newCol -value ''
                }
                write-log "header extended" -type info
            }
            'c' {
                write-log "continuing without header change" -type info
            }
            default {
                write-log "cancelled. exitting." -type info
                exit -7
            }
        }
    }
    return $CSVData
}

function new-RandomPassword {
    <#
    .SYNOPSIS
        generate random password with given char ranges (complexity) and lenght
    .DESCRIPTION
        by default it genrates 8-long string with
    .EXAMPLE
        $pass = new-RandomPassword
 
        generated 8-char long semi-complex password
    .EXAMPLE
        $pass = new-RandomPassword -specialCharacterRange 3
 
        generated 8-char long password with full complexity
    .INPUTS
        None.
    .OUTPUTS
        string of random characters
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210127
            last changes
            - 210127 initialized
    #>

    
    param( 
        #password length
        [Parameter(mandatory=$false,position=0)]
            [int]$length=8,
        #password complexity based on a range of special characters.
        [Parameter(mandatory=$false,position=1)]
            [int][validateSet(1,2,3)]$specialCharacterRange=1,
        #uniquness - related to complexity, recommended to leave. this guarantee that password will have characters from given number of char sets.
        [Parameter(mandatory=$false,position=2)]
            [int][validateSet(1,2,3,4)]$uniqueSets=4
            
    )
    function generate-Set {
        param(
            # set up password length
            [int]$length,
            # number of 'sets of sets' defining complexity range
            [int]$setSize
        )
        $safe=0
        while ($safe++ -lt 100) {
            $array=@()
            1..$length|%{
                $array+=(Get-Random -Maximum ($setSize) -Minimum 0)
            }
            if(($array|Sort-Object -Unique|Measure-Object).count -ge $setSize) {
                return $array
            } else {
                Write-Verbose "[generate-Set]bad array: $($array -join ',')"
            }
        }
        return $null
    }
    #prepare char-sets
    $smallLetters=$null
    97..122|%{$smallLetters+=,[char][byte]$_}
    $capitalLetters=$null
    65..90|%{$capitalLetters+=,[char][byte]$_}
    $numbers=$null
    48..57|%{$numbers+=,[char][byte]$_}
    $specialCharacterL1=$null
    @(33;35..38;43;45..46;95)|%{$specialCharacterL1+=,[char][byte]$_} # !"#$%&
    $specialCharacterL2=$null
    58..64|%{$specialCharacterL2+=,[char][byte]$_} # :;<=>?@
    $specialCharacterL3=$null
    @(34;39..42;44;47;91..94;96;123..125)|%{$specialCharacterL3+=,[char][byte]$_} # [\]^`
      
    $ascii=@()
    $ascii+=,$smallLetters
    $ascii+=,$capitalLetters
    $ascii+=,$numbers
    if($specialCharacterRange -ge 2) { $specialCharacterL1+=,$specialCharacterL2 }
    if($specialCharacterRange -ge 3) { $specialCharacterL1+=,$specialCharacterL3 }
    $ascii+=,$specialCharacterL1
    #prepare set of character-sets ensuring that there will be at least one character from at least $uniqueSets different sets
    $passwordSet = generate-Set -length $length -setSize $uniqueSets 

    $password=$NULL
    0..($length-1)|% {
        $password+=($ascii[$passwordSet[$_]] | Get-Random)
    }
    return $password
}

#################################################### PowerShell GUI
function get-AnswerBox {
    <#
    .SYNOPSIS
        win32 forms message box to get YES/NO input from user
    .DESCRIPTION
        replacement for simple messageBox giving option to customize buttons, giving option
        to add some additional information
    .EXAMPLE
        $response = get-answerBox -OKButtonText 'YES' -CancelButtonText 'NO' -info 'choose your answer' -message 'do you find this function useful?'
        if($response) {
            write-host 'thank you!'
        }
    .INPUTS
        None.
    .OUTPUTS
        true/false
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210209
            last changes
            - 210209 detailedInfo -> message (alias left for compatibility), autosize, anchors
            - 210208 icon, tune, info -> title
            - 210127 module
            - 210110 initialized
         
        #TO|DO
    #>

    
    param(
        #OK button text
        [Parameter(mandatory=$false,position=0)]
            [string]$OKButtonText = "OK",
        #Canel button text
        [Parameter(mandatory=$false,position=1)]
            [string]$CancelButtonText = "Cancel",
        #title bar text
        [Parameter(mandatory=$false,position=2)]
            [string]$title = "Which option?",
        #message text
        [Parameter(mandatory=$false,position=3)]
            [alias('detailedInfo')]
            [string]$message = "What is your choice:",
        #messagebox icon
        [Parameter(mandatory=$false,position=4)]
            [validateSet('Asterisk','Error','Exclamation','Hand','Information','None','Question','Stop','Warning')]
            [string]$icon='Question'
    )
    Add-Type -AssemblyName System.Windows.Forms
    Add-Type -AssemblyName System.Drawing
    [System.Windows.Forms.Application]::EnableVisualStyles()
    
    $messageBoxForm = New-Object System.Windows.Forms.Form
    $messageBoxForm.Text = $title
    $messageBoxForm.Size = New-Object System.Drawing.Size(300,120)
    $messageBoxForm.AutoSize = $true
    $messageBoxForm.StartPosition = 'CenterScreen'
    $messageBoxForm.FormBorderStyle = 'Fixed3D'
    $messageBoxForm.Icon = [System.Drawing.SystemIcons]::$icon
    $messageBoxForm.Topmost = $true
    $messageBoxForm.MaximizeBox = $false
   
    $okButton = New-Object System.Windows.Forms.Button
    $okButton.Location = New-Object System.Drawing.Point(50,50)
    $okButton.Size = New-Object System.Drawing.Size(75,23)
    $okButton.Anchor = 'left,bottom'
    $okButton.Text = $OKButtonText
    $okButton.DialogResult = [System.Windows.Forms.DialogResult]::OK
    $messageBoxForm.AcceptButton = $okButton
    $messageBoxForm.Controls.Add($okButton)
    
    $cancelButton = New-Object System.Windows.Forms.Button
    $cancelButton.Location = New-Object System.Drawing.Point(160,50)
    $cancelButton.Size = New-Object System.Drawing.Size(75,23)
    $cancelButton.Anchor = 'right,bottom'
    $cancelButton.Text = $CancelButtonText
    $cancelButton.DialogResult = [System.Windows.Forms.DialogResult]::Cancel
    $messageBoxForm.CancelButton = $cancelButton
    $messageBoxForm.Controls.Add($cancelButton)
    
    $label = New-Object System.Windows.Forms.Label
    $label.Location = New-Object System.Drawing.Point(10,20)
    
    $label.AutoSize = $true
    $label.Anchor = 'left,top'
    $label.Text = $message
    $messageBoxForm.Controls.Add($label)
   
    $result = $messageBoxForm.ShowDialog()
    if ($result -eq [System.Windows.Forms.DialogResult]::OK) {
        return $true
    } 
    return $false
}

function get-valueFromInputBox {
    <#
    .SYNOPSIS
        simple input message box function for PS GUI scripts
    .EXAMPLE
        $response = get-valueFromInputBox -title 'WARNING!' -text "type 'YES' to continue" -type Warning
        if($null -eq $response) {
            'cancelled'
            exit 0
        }
        if($response -ne 'YES') {
            'not correct. quitting'
            exit -1
        } else {
            "you agreed, let's continue"
        }
        write-host 'code to execute here'
    .INPUTS
        None.
    .OUTPUTS
        User Input or $null for cancel
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210209
        last changes
            - 210209 anchored layout
            - 210113 initialized
         
        #TO|DO
    #>

    
    param(
        [parameter(mandatory=$false,position=0)]
            [string]$title='input',
        [parameter(mandatory=$false,position=1)]
            [alias('text')]
            [string]$message='put your input',
        [parameter(mandatory=$false,position=2)]
            [validateSet('Asterisk','Error','Exclamation','Hand','Information','None','Question','Stop','Warning')]
            [string]$type='Question',
        #maximum number of characters allowed
        [Parameter(mandatory=$false,position=3)]
            [int]$maxChars = 30
    )
    Add-Type -AssemblyName System.Drawing
    Add-Type -AssemblyName System.Windows.Forms
    [System.Windows.Forms.Application]::EnableVisualStyles()

    $promptWindowForm = New-Object system.Windows.Forms.Form
    $promptWindowForm.Size = New-Object System.Drawing.Size(250,140)
    $promptWindowForm.text = $title
    $promptWindowForm.BackColor = "#ffffff"
    $promptWindowForm.AutoSize = $true
    $promptWindowForm.StartPosition = 'CenterScreen'
    $promptWindowForm.FormBorderStyle = 'Fixed3D'
    $promptWindowForm.MaximizeBox = $false
    $promptWindowForm.Icon = [System.Drawing.SystemIcons]::$type
    $promptWindowForm.Font = New-Object System.Drawing.Font('Microsoft Sans Serif', 10)

    $lblPromptInfo = New-Object System.Windows.Forms.Label 
    $lblPromptInfo.Location = New-Object System.Drawing.Size(10,5) 
    #$lblPromptInfo.Size = New-Object System.Drawing.Size(230,40)
    $lblPromptInfo.AutoSize = $true
    $lblPromptInfo.MinimumSize = New-Object System.Drawing.Size(235,10)
    $lblPromptInfo.Anchor = 'left,top'
    $lblPromptInfo.Text = $message

    $txtUserInput = New-Object system.Windows.Forms.TextBox
    $txtUserInput.multiline = $false
    $txtUserInput.ReadOnly = $false
    $txtUserInput.MinimumSize = New-Object System.Drawing.Size(230,25)
    $txtUserInput.autosize = $true
    $txtUserInput.Anchor = "none" #effectively - center
    $txtUserInput.MaxLength = $maxChars
    $txtUserInput.location = New-Object System.Drawing.Point(0, 35)

    $btOK = New-Object System.Windows.Forms.Button
    $btOK.Location = New-Object System.Drawing.Size(30,70) 
    $btOK.Size = New-Object System.Drawing.Size(70,20)
    $btOK.ForeColor = "Green"
    $btOK.Anchor = "left,bottom"
    $btOK.Text = "Continue"
    $btOK.DialogResult = [System.Windows.Forms.DialogResult]::OK

    $btCancel = New-Object System.Windows.Forms.Button
    $btCancel.Location = New-Object System.Drawing.Size(150,70) 
    $btCancel.Size = New-Object System.Drawing.Size(70,20)
    $btCancel.ForeColor = "Red"
    $btCancel.Anchor = "right,bottom"
    $btCancel.Text = "Cancel"
    $btCancel.DialogResult = [System.Windows.Forms.DialogResult]::Cancel

    $promptWindowForm.AcceptButton=$btOK
    $promptWindowForm.CancelButton=$btCancel
    $promptWindowForm.Controls.AddRange(@($lblPromptInfo, $txtUserInput,$btOK,$btCancel))
    $promptWindowForm.Topmost = $true
    $promptWindowForm.Add_Shown( { $promptWindowForm.Activate();$txtUserInput.Select() })
    $result = $promptWindowForm.ShowDialog()
    if ($result -eq [System.Windows.Forms.DialogResult]::OK) {
        $response = $txtUserInput.Text
        return $response
    }
    else {
        return $null
    }   
}

#################################################### connection checkers
function get-ExchangeConnectionStatus {
    <#
    .SYNOPSIS
        check Ex/EXO connection status.
    .DESCRIPTION
        Exchange is using Remoting commands. this function verifies if session connection exists.
    .EXAMPLE
        get-ExchangeConnectionStatus -isCritical
 
        checks connection and exits if not present.
    .EXAMPLE
        if(-not get-ExchangeConnectionStatus) {
            write-log "you should connect to Exchange first, scrpt will run with limited options"
        }
 
        checks connection and warns about lack of Exchange connectivity.
    .INPUTS
        None.
    .OUTPUTS
        None.
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210208
            last changes
            - 210208 initialized
     
        #TO|DO
        - isCritical flag
        - verify domain name
 
    #>

    
    param(
        #define if connection to EXO or Ex Onprem
        [parameter(mandatory=$false,position=0)]
            [validateSet('OnPrem','EXO')]
            [string]$ExType='EXO',
        #if connection is not established exit with error instead of returning $false.
        [parameter(mandatory=$false,position=1)]
            [switch]$isCritical
            
    )

    $exConnection=$false
    foreach($session in $(get-PSSession)) {
        if($session.ConfigurationName -eq 'Microsoft.Exchange') {
            if($ExType -eq 'EXO' -and $session.ComputerName -eq 'outlook.office365.com') {
                $exConnection=$true
            }
            if($ExType -eq 'OnPrem' -and $session.ComputerName -ne 'outlook.office365.com') {
                $exConnection=$true
            }
        }
    }
    if($isCritical.IsPresent -and !$exConnection) {
        write-log "connection to $ExType not established. quitting." -type error
        exit -1
    }
    return $exConnection
}

function connect-Azure {
    <#
    .SYNOPSIS
        quick Azure connection check by verifying AzContext.
    .DESCRIPTION
        there is no session to Azure and Az commandlets are using saved AzContext and token. when
        token expires, context is returned, but connection attemt will return error. to clean it up
        - best is to clear context and exforce re-authentication.
    .EXAMPLE
        connect-Azure
 
        checks AzContext
    .INPUTS
        None.
    .OUTPUTS
        None.
    .LINK
        https://w-files.pl
    .NOTES
        nExoR ::))o-
        version 210208
            last changes
            - 210208 initialized
     
        #TO|DO
    #>

    
    try {
        $AzSourceContext=Get-AzContext
    } catch {
        write-log $_.exception -type error
        write-log "trying to fix" -type info
        Clear-AzContext -Force
        write-log "re-run the script."
        exit -1
    }
    if([string]::IsNullOrEmpty( $AzSourceContext ) ) {
            write-log "you need to be connected before running this script. use connect-AzAccount first." -type warning
            $AzSourceContext = Connect-AzAccount
            if([string]::isNullOrEmpty($AzSourceContext) ) {
                write-log "cancelled"
                exit 0
            }
    }
    write-log "connected to $($AzSourceContext.Subscription.name) as $($AzSourceContext.account.id)" -silent -type info
    write-host "Your Azure connection:"
    write-host " subscription: " -noNewLine
    write-host -foreground Yellow "$($AzSourceContext.Subscription.name)"
    write-host " connected as: " -noNewLine 
    write-host -foreground Yellow "$($AzSourceContext.account.id)"
    Set-Item Env:\SuppressAzurePowerShellBreakingChangeWarnings "true"
}

Export-ModuleMember -Function * -Variable 'logFile'