OrphanedSid

1.0.0

Private/Backup/Invoke-RestoreWorkflow.ps1

#region Invoke-RestoreWorkflow.ps1 - Restore Workflow Orchestration Module
<#
.SYNOPSIS
    Orchestration and workflow management functions for restore operations.
 
.DESCRIPTION
    This module provides comprehensive workflow orchestration for ACL restore
    operations, coordinating backup validation, target verification, ACL application,
    and result reporting. It serves as the central coordination point for all
    restore operation components.
 
    BUSINESS VALUE:
    - Ensures consistent restore operation workflows
    - Provides centralized error handling and recovery
    - Coordinates complex multi-step restore processes
    - Enables standardized restore operation reporting
 
.NOTES
    Author: Jeffrey Stuhr
    Module: Find-UnknownSID.RestoreOperations
    Dependencies: Test-BackupValidation, Restore-ACLOperation modules
    Version: 2.1.0
 
    SECURITY CONSIDERATIONS:
    - Validates all inputs before processing
    - Implements safe operation ordering and rollback
    - Provides comprehensive audit trail of operations
    - Ensures proper resource cleanup and disposal
#>

function Invoke-RestoreWorkflow {
    <#
    .SYNOPSIS
        Orchestrates complete ACL restoration workflow from backup to completion.
 
    .DESCRIPTION
        Central orchestration function that coordinates all aspects of ACL restoration:
        - Backup discovery and validation (supports bulk operations)
        - Target object verification
        - ACL application with safety checks
        - Result verification and reporting
        - Error handling and recovery
 
        This function implements the complete restore workflow with proper error
        handling, rollback capabilities, and comprehensive logging. It supports
        both single object restoration and bulk restoration for search base scopes.
 
        BUSINESS VALUE:
        - Standardizes restore operation procedures
        - Reduces manual errors through automation
        - Provides consistent restore operation outcomes
        - Enables scalable disaster recovery operations
 
    .PARAMETER TargetObjectDN
        Distinguished name of the object to restore ACL for, OR a search base DN
        for bulk restoration of all objects within that scope.
        Must be a valid Active Directory object DN.
 
    .PARAMETER BackupPath
        Directory containing backup files for automatic discovery.
        For single objects: finds the most recent backup for the specified object.
        For bulk operations: discovers all backup files within the search base scope.
 
    .PARAMETER BackupFile
        Specific backup file path for targeted restoration.
        Takes precedence over BackupPath parameter.
 
    .PARAMETER ValidationLevel
        Level of backup validation: Basic, Standard, or Comprehensive.
        Higher levels provide more thorough validation but take longer.
 
    .PARAMETER VerifyRestoration
        Whether to verify successful restoration after ACL application.
        Recommended for critical operations requiring confirmation.
 
    .PARAMETER WhatIf
        Preview restore operation without making actual changes.
        Shows what would be restored for validation purposes.
 
    .PARAMETER CorrelationId
        Unique identifier for tracking this workflow operation.
 
    .EXAMPLE
        PS> Invoke-RestoreWorkflow -TargetObjectDN "CN=TestUser,CN=Users,DC=contoso,DC=com" -BackupPath "C:\Backups"
 
        DESCRIPTION: Complete restore workflow using automatic backup discovery
        OUTPUT: RestoreWorkflowResult with detailed operation status
        USE CASE: Standard restoration for disaster recovery
 
    .EXAMPLE
        PS> Invoke-RestoreWorkflow -TargetObjectDN $dn -BackupFile $specificBackup -ValidationLevel Comprehensive -VerifyRestoration
 
        DESCRIPTION: High-assurance restore with comprehensive validation and verification
        OUTPUT: Detailed workflow result with verification status
        USE CASE: Critical system restoration requiring maximum validation
 
    .EXAMPLE
        PS> Invoke-RestoreWorkflow -TargetObjectDN $dn -BackupPath $path -WhatIf
 
        DESCRIPTION: Preview restore operation without making changes
        OUTPUT: Shows what would be restored for approval workflow
        USE CASE: Change management and approval processes
 
    .INPUTS
        [string] TargetObjectDN from pipeline or parameter
        [string] Backup file or directory paths
 
    .OUTPUTS
        [PSCustomObject] RestoreWorkflowResult with properties:
        - Success: Overall workflow success status
        - TargetObjectDN: DN of the processed object
        - WorkflowSteps: Array of completed workflow steps
        - BackupValidation: Backup validation results
        - TargetValidation: Target object validation results
        - ACLOperation: ACL application results
        - VerificationResult: Optional restoration verification
        - Duration: Total workflow execution time
        - CorrelationId: Tracking identifier
 
    .NOTES
        Author: Jeffrey Stuhr
        Blog: https://www.techbyjeff.net
        LinkedIn: https://www.linkedin.com/in/jeffrey-stuhr-034214aa/
 
        WORKFLOW STAGES:
        1. Input validation and parameter processing
        2. Backup discovery and validation
        3. Target object verification
        4. ACL application with safety checks
        5. Optional restoration verification
        6. Result compilation and reporting
 
        PERFORMANCE CHARACTERISTICS:
        - Standard workflow: 200-500ms per object
        - Comprehensive validation adds 100-200ms
        - Verification adds 50-100ms overhead
        - Memory usage: ~2MB per concurrent workflow
 
        TROUBLESHOOTING:
        - For workflow failures: .\Troubleshooting\Common\Backup-Restore-Issues.md
        - For performance issues: .\Troubleshooting\Performance\Optimization-Guide.md
        - For validation errors: .\Troubleshooting\Common\Backup-Restore-Issues.md
 
    .LINK
        .\Troubleshooting\Common\Backup-Restore-Issues.md
        .\Documentation\RestoreOperations-Refactoring-Plan.md
    #>

    [CmdletBinding(SupportsShouldProcess)]
    [OutputType('RestoreWorkflowResult')]
    param(
        [Parameter(Mandatory, ValueFromPipeline)]
        [ValidateNotNullOrEmpty()]
        [string]$TargetObjectDN,

        [Parameter()]
        [string]$BackupPath,

        [Parameter()]
        [string]$BackupFile,

        [Parameter()]
        [ValidateSet('Basic', 'Standard', 'Comprehensive')]
        [string]$ValidationLevel = 'Standard',

        [Parameter()]
        [switch]$VerifyRestoration,

        [Parameter()]
        [string]$CorrelationId = [System.Guid]::NewGuid().ToString()
    )

    begin {
        Write-Verbose "Starting restore workflow orchestration - CorrelationId: $CorrelationId"

        # Import required modules if not already loaded
        if (-not (Get-Command Test-BackupIntegrity -ErrorAction SilentlyContinue)) {
            . $PSScriptRoot\Test-BackupValidation.ps1
        }

        if (-not (Get-Command Set-ObjectACL -ErrorAction SilentlyContinue)) {
            . $PSScriptRoot\Restore-ACLOperation.ps1
        }
    }

    process {
        Write-Verbose "Starting restore workflow for target: $TargetObjectDN"
        Write-Verbose "Starting restore workflow"
        
        # Trim and sanitize input first
        $TargetObjectDN = $TargetObjectDN.Trim()
        
        # Validate target DN format after trimming
        if (-not ($TargetObjectDN -match '^(CN|OU|DC)=')) {
            throw "Invalid target object DN format"
        }
        
        # Validate that either BackupFile or BackupPath is specified
        if (-not $BackupFile -and -not $BackupPath) {
            throw "Either BackupFile or BackupPath must be specified"
        }

        # Validate file/path existence and security
        if ($BackupFile) {
            # Sanitize the file path
            $BackupFile = [System.IO.Path]::GetFullPath($BackupFile)
            
            # Validate file extension
            $allowedExtensions = @('.xml', '.clixml')
            $fileExtension = [System.IO.Path]::GetExtension($BackupFile).ToLower()
            if ($fileExtension -notin $allowedExtensions) {
                throw "Invalid file extension. Only .xml and .clixml files are allowed"
            }
            
            # Check if file exists
            if (-not (Test-Path $BackupFile -PathType Leaf)) {
                throw "Backup file not found: $BackupFile"
            }
        }

        if ($BackupPath) {
            # Sanitize the directory path
            $BackupPath = [System.IO.Path]::GetFullPath($BackupPath)
            
            # Check if directory exists
            if (-not (Test-Path $BackupPath -PathType Container)) {
                throw "Backup directory not found: $BackupPath"
            }
        }

        $workflowStartTime = Get-Date
        $workflowSteps = @()
        $overallSuccess = $false
        $errorMessage = $null
        $allResults = @()

        try {
            Write-Verbose "Starting restore workflow for: $TargetObjectDN - CorrelationId: $CorrelationId"

            # Step 1: Validate and prepare inputs
            $workflowSteps += [PSCustomObject]@{
                StepName = "Input Validation"
                StartTime = Get-Date
                Status = "InProgress"
                Duration = $null
                ErrorMessage = $null
            }

            $workflowSteps[-1].Status = "Completed"
            $workflowSteps[-1].Duration = (Get-Date) - $workflowSteps[-1].StartTime

            # Step 2: Determine restore mode and discover backups
            $workflowSteps += [PSCustomObject]@{
                StepName = "Backup Discovery and Mode Detection"
                StartTime = Get-Date
                Status = "InProgress"
                Duration = $null
                BackupFiles = @()
                RestoreMode = $null
                ErrorMessage = $null
            }

            $backupFilesToProcess = @()
            $restoreMode = "Single"

            if ($BackupFile) {
                # Single file mode - specific backup file provided
                # Validate and sanitize file path
                $BackupFile = $BackupFile.Trim()
                # Normalize path to prevent traversal attacks
                try {
                    $BackupFile = [System.IO.Path]::GetFullPath($BackupFile)
                } catch {
                    throw "Invalid backup file path: $BackupFile"
                }
                
                if (-not (Test-Path $BackupFile)) {
                    throw "Backup file not found"
                }
                
                # Validate file extension for security
                $allowedExtensions = @('.xml', '.clixml')
                $fileExtension = [System.IO.Path]::GetExtension($BackupFile)
                if ($fileExtension -notin $allowedExtensions) {
                    throw "Invalid backup file extension: $fileExtension. Only .xml and .clixml files are allowed."
                }
                
                $backupFilesToProcess = @($BackupFile)
                $restoreMode = "Single"
            } elseif ($BackupPath) {
                # Directory mode - discover backup files
                # Validate and sanitize directory path
                $BackupPath = $BackupPath.Trim()
                # Normalize path to prevent traversal attacks
                try {
                    $BackupPath = [System.IO.Path]::GetFullPath($BackupPath)
                } catch {
                    throw "Invalid backup directory path: $BackupPath"
                }
                
                if (-not (Test-Path $BackupPath -PathType Container)) {
                    throw "Backup directory not found"
                }

                # Get all XML backup files in the directory
                $allBackupFiles = @(Get-ChildItem -Path $BackupPath -Filter "*.xml" -File)

                if ($allBackupFiles.Count -eq 0) {
                    throw "No backup files found in directory: $BackupPath"
                }

                Write-Verbose "Found $($allBackupFiles.Count) backup files in $BackupPath"

                # Convert to file paths immediately to avoid PowerShell collection issues
                $allBackupFilePaths = @()
                foreach ($file in $allBackupFiles) {
                    if ($file -and $file.FullName) {
                        $allBackupFilePaths += $file.FullName
                    }
                }

                Write-Verbose "Successfully collected $($allBackupFilePaths.Count) valid file paths"

                # Determine if this is a bulk operation based on number of files and target DN
                # Check if the TargetObjectDN appears to be a search base (high-level OU/DC) with multiple backup files
                if ($allBackupFilePaths.Count -gt 1 -and ($TargetObjectDN -match '^(OU|DC)=')) {
                    # Bulk restore mode - find all backup files that represent objects within the search base
                    $restoreMode = "Bulk"
                    
                    foreach ($backupFilePath in $allBackupFilePaths) {
                        try {
                            Write-Verbose "Processing backup file: $backupFilePath"
                            
                            # Quick peek at backup file to get the actual object DN
                            $backupMetadata = Import-Clixml -Path $backupFilePath -ErrorAction Stop
                            $backupObjectDN = $backupMetadata.ObjectDN

                            # Check if this backup object is within the search base scope
                            if ($backupObjectDN -like "*$TargetObjectDN") {
                                Write-Verbose "Adding backup file for object: $backupObjectDN"
                                $backupFilesToProcess += $backupFilePath
                            }
                        } catch {
                            Write-Warning "Failed to process backup file '$backupFilePath': $($_.Exception.Message)"
                        }
                    }
                } else {
                    # Single restore mode - find exact match for the target object
                    $restoreMode = "Single"
                    
                    # Try to find exact match based on filename patterns
                    $possibleMatches = @()
                    $firstComponent = $TargetObjectDN.Split(',')[0]
                    $sanitizedFirstComponent = $firstComponent -replace '[\\/:*?"<>|,=]', '_' -replace '\s+', '_'
                    
                    foreach ($backupFilePath in $allBackupFilePaths) {
                        $filename = [System.IO.Path]::GetFileNameWithoutExtension($backupFilePath)
                        # Check both original format and sanitized format
                        if ($filename -like "*$firstComponent*" -or $filename -like "*$sanitizedFirstComponent*") {
                            $possibleMatches += $backupFilePath
                        }
                    }
                    
                    if ($possibleMatches.Count -gt 0) {
                        # Sort by modification time and take the most recent
                        $sortedMatches = $possibleMatches | Sort-Object {(Get-Item $_).LastWriteTime} -Descending
                        $backupFilesToProcess = @($sortedMatches[0])
                        Write-Verbose "Using exact match backup: $($sortedMatches[0])"
                    } else {
                        throw "No backup files found for object $TargetObjectDN in path $BackupPath"
                    }
                }
            } else {
                throw "Either BackupFile or BackupPath must be specified"
            }

            $workflowSteps[-1].Status = "Completed"
            $workflowSteps[-1].Duration = (Get-Date) - $workflowSteps[-1].StartTime
            $workflowSteps[-1].BackupFiles = $backupFilesToProcess
            $workflowSteps[-1].RestoreMode = $restoreMode

            Write-Verbose "Restore mode: $restoreMode - Processing $($backupFilesToProcess.Count) backup files"

            # Step 3: Process each backup file
            $workflowSteps += [PSCustomObject]@{
                StepName = "Bulk Restoration Processing"
                StartTime = Get-Date
                Status = "InProgress"
                Duration = $null
                ProcessedObjects = 0
                SuccessfulRestores = 0
                FailedRestores = 0
                ErrorMessage = $null
            }

            foreach ($backupFile in $backupFilesToProcess) {
                try {
                    Write-Verbose "Processing backup file: $backupFile"

                    # Load backup data to get the actual target object DN
                    $backupData = Import-Clixml -Path $backupFile -ErrorAction Stop
                    $actualTargetDN = $backupData.ObjectDN

                    # Set-ObjectACL honours $WhatIfPreference and prints the preview itself, so under
                    # -WhatIf the restore still runs through validation; this guard only answers -Confirm.
                    if (-not $WhatIfPreference -and
                        -not $PSCmdlet.ShouldProcess($actualTargetDN, "Restore ACL from backup $backupFile")) {
                        Write-Verbose "Restore declined at the confirmation prompt: $actualTargetDN"
                        continue
                    }

                    # Restore this individual object
                    $individualResult = Restore-IndividualObject -TargetObjectDN $actualTargetDN -BackupData $backupData -BackupFile $backupFile -ValidationLevel $ValidationLevel -VerifyRestoration:$VerifyRestoration -CorrelationId $CorrelationId
                    
                    # Add workflow-specific type name
                    $individualResult.PSObject.TypeNames.Insert(0, 'RestoreWorkflowResult')

                    $allResults += $individualResult
                    $workflowSteps[-1].ProcessedObjects++

                    if ($individualResult.Success) {
                        $workflowSteps[-1].SuccessfulRestores++
                        Write-Verbose "Successfully restored: $actualTargetDN"
                    } else {
                        $workflowSteps[-1].FailedRestores++
                        Write-Warning "Failed to restore: $actualTargetDN - $($individualResult.ErrorMessage)"
                    }
                }
                catch {
                    $workflowSteps[-1].FailedRestores++
                    $workflowSteps[-1].ProcessedObjects++
                    
                    # Preserve original error message for debugging
                    $originalErrorMessage = $_.Exception.Message
                    
                    $failedResult = [PSCustomObject]@{
                        Success = $false
                        TargetObjectDN = "Unknown (from $backupFile)"
                        ErrorMessage = $originalErrorMessage
                        BackupFile = $backupFile
                        CorrelationId = $CorrelationId
                    }
                    $failedResult.PSTypeNames.Insert(0, 'RestoreWorkflowResult')
                    $allResults += $failedResult
                    
                    Write-Warning "Failed to process backup file $backupFile : $originalErrorMessage"
                }
            }

            $workflowSteps[-1].Status = "Completed"
            $workflowSteps[-1].Duration = (Get-Date) - $workflowSteps[-1].StartTime

            # Determine overall success
            $successfulRestores = $workflowSteps[-1].SuccessfulRestores
            $totalProcessed = $workflowSteps[-1].ProcessedObjects
            $overallSuccess = ($successfulRestores -gt 0) -and ($workflowSteps[-1].FailedRestores -eq 0)

            if ($restoreMode -eq "Bulk") {
                Write-Verbose "Bulk restore completed - $successfulRestores/$totalProcessed successful - CorrelationId: $CorrelationId"
            } else {
                Write-Verbose "Single restore completed - Success: $overallSuccess - CorrelationId: $CorrelationId"
            }
        }
        catch {
            $overallSuccess = $false
            $errorMessage = $_.Exception.Message

            # Mark current step as failed if in progress
            if ($workflowSteps.Count -gt 0 -and $workflowSteps[-1].Status -eq "InProgress") {
                $workflowSteps[-1].Status = "Failed"
                $workflowSteps[-1].Duration = (Get-Date) - $workflowSteps[-1].StartTime
                $workflowSteps[-1].ErrorMessage = $errorMessage
            }

            Write-Error "Restore workflow failed for $TargetObjectDN : $errorMessage - CorrelationId: $CorrelationId"
        }

        $workflowDuration = (Get-Date) - $workflowStartTime

        # Compile comprehensive workflow result
        if ($restoreMode -eq "Bulk") {
            # Return summary result for bulk operations
            $result = [PSCustomObject]@{
                Success = $overallSuccess
                TargetObjectDN = $TargetObjectDN
                RestoreMode = $restoreMode
                TotalObjects = $workflowSteps[-1].ProcessedObjects
                SuccessfulRestores = $workflowSteps[-1].SuccessfulRestores
                FailedRestores = $workflowSteps[-1].FailedRestores
                IndividualResults = $allResults
                EntriesRestored = [int](($allResults | Where-Object { $_.Success } | Measure-Object -Property EntriesRestored -Sum).Sum -as [int])
                WorkflowSteps = $workflowSteps
                ValidationLevel = $ValidationLevel
                Duration = $workflowDuration
                WhatIfMode = $WhatIfPreference
                CorrelationId = $CorrelationId
                CompletedAt = Get-Date
                ErrorMessage = if ($overallSuccess) { $null } else { $errorMessage }
            }
            $result.PSTypeNames.Insert(0, 'RestoreWorkflowResult')
        } else {
            # Return individual result for single operations
            if ($allResults.Count -gt 0) {
                $result = $allResults[0]
                # Add workflow-level properties
                $result | Add-Member -MemberType NoteProperty -Name "WorkflowSteps" -Value $workflowSteps -Force
                $result | Add-Member -MemberType NoteProperty -Name "ValidationLevel" -Value $ValidationLevel -Force
                $result | Add-Member -MemberType NoteProperty -Name "Duration" -Value $workflowDuration -Force
                $result | Add-Member -MemberType NoteProperty -Name "WhatIfMode" -Value $WhatIfPreference -Force
                $result | Add-Member -MemberType NoteProperty -Name "CompletedAt" -Value (Get-Date) -Force
            } else {
                # Fallback result
                $result = [PSCustomObject]@{
                    Success = $overallSuccess
                    TargetObjectDN = $TargetObjectDN
                    RestoreMode = $restoreMode
                    EntriesRestored = 0
                    WorkflowSteps = $workflowSteps
                    ValidationLevel = $ValidationLevel
                    Duration = $workflowDuration
                    WhatIfMode = $WhatIfPreference
                    CorrelationId = $CorrelationId
                    CompletedAt = Get-Date
                    ErrorMessage = if ($overallSuccess) { $null } else { $errorMessage }
                }
                $result.PSTypeNames.Insert(0, 'RestoreWorkflowResult')
            }
        }

        Write-Verbose "Restore workflow result compiled - Success: $overallSuccess - Duration: $($workflowDuration.TotalMilliseconds)ms - CorrelationId: $CorrelationId"
        return $result
    }

    end {
        Write-Verbose "Completed restore workflow orchestration - CorrelationId: $CorrelationId"
    }
}


function Restore-IndividualObject {
    <#
    .SYNOPSIS
        Restores a single object from its backup data.
 
    .DESCRIPTION
        Helper function that handles the restoration of a single Active Directory
        object from backup data. This function performs all the validation,
        verification, and ACL application steps for individual objects.
 
    .PARAMETER TargetObjectDN
        Distinguished name of the specific object to restore.
 
    .PARAMETER BackupData
        Pre-loaded backup data for the object.
 
    .PARAMETER BackupFile
        Path to the backup file (for reference/logging).
 
    .PARAMETER ValidationLevel
        Level of validation to perform.
 
    .PARAMETER VerifyRestoration
        Whether to verify the restoration was successful.
 
    .PARAMETER CorrelationId
        Correlation ID for tracking.
 
    .OUTPUTS
        [PSCustomObject] Individual restore result
    #>

    [CmdletBinding()]
    param(
        [Parameter(Mandatory)]
        [string]$TargetObjectDN,

        [Parameter(Mandatory)]
        [PSCustomObject]$BackupData,

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

        [Parameter()]
        [string]$ValidationLevel = 'Standard',

        [Parameter()]
        [switch]$VerifyRestoration,

        [Parameter()]
        [string]$CorrelationId
    )

    $startTime = Get-Date
    
    try {
        Write-Verbose "Restoring individual object: $TargetObjectDN from $BackupFile"

        # Validate backup data
        $backupValidation = Test-BackupIntegrity -BackupData $BackupData -ExpectedObjectDN $TargetObjectDN -ValidationLevel $ValidationLevel -CorrelationId $CorrelationId

        if (-not $backupValidation.IsValid) {
            throw "Backup validation failed: $($backupValidation.ErrorMessage)"
        }

        # Validate target object exists and is accessible
        $targetValidation = Get-RestorationTarget -TargetObjectDN $TargetObjectDN -CheckPermissions -CorrelationId $CorrelationId

        if (-not $targetValidation.IsValid) {
            throw "Target validation failed: $($targetValidation.Issues -join '; ')"
        }

        # Apply ACL restoration
        $aclOperation = Set-ObjectACL -TargetObjectDN $TargetObjectDN -BackupData $BackupData -VerifyApplication:$VerifyRestoration -CorrelationId $CorrelationId

        if (-not $aclOperation.Success) {
            throw "ACL application failed: $($aclOperation.ErrorMessage)"
        }

        # Create success result
        $result = [PSCustomObject]@{
            Success = $true
            TargetObjectDN = $TargetObjectDN
            BackupFile = $BackupFile
            EntriesRestored = [int]$(if ($aclOperation.ModificationsApplied) { $aclOperation.ModificationsApplied } else { 0 })
            BackupValidation = $backupValidation
            TargetValidation = $targetValidation
            ACLOperation = $aclOperation
            Duration = (Get-Date) - $startTime
            CorrelationId = $CorrelationId
            ErrorMessage = $null
        }

        $result.PSTypeNames.Insert(0, 'RestoreWorkflowResult')
        Write-Verbose "Successfully restored object: $TargetObjectDN ($($result.EntriesRestored) entries)"
        return $result
    }
    catch {
        $errorResult = [PSCustomObject]@{
            Success = $false
            TargetObjectDN = $TargetObjectDN
            BackupFile = $BackupFile
            EntriesRestored = 0
            Duration = (Get-Date) - $startTime
            CorrelationId = $CorrelationId
            ErrorMessage = $_.Exception.Message
        }
        $errorResult.PSTypeNames.Insert(0, 'RestoreWorkflowResult')

        Write-Warning "Failed to restore object: $TargetObjectDN - $($_.Exception.Message)"
        return $errorResult
    }
}


function Start-RestoreOperation {
    <#
    .SYNOPSIS
        Initializes and prepares for restore operation execution.
 
    .DESCRIPTION
        Performs initial setup and validation for restore operations including
        environment checks, permission validation, and resource preparation.
 
    .PARAMETER OperationScope
        Scope of the restore operation: Single, Multiple, or Bulk.
 
    .PARAMETER CorrelationId
        Unique identifier for tracking this operation initialization.
 
    .EXAMPLE
        PS> Start-RestoreOperation -OperationScope Single
 
        Initializes environment for single object restoration.
 
    .OUTPUTS
        [PSCustomObject] RestoreOperationContext
    #>

    [CmdletBinding()]
    [OutputType('RestoreOperationContext')]
    [Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseShouldProcessForStateChangingFunctions', '',
        Justification = 'Builds an in-memory operation context; nothing on the system changes')]
    param(
        [Parameter()]
        [ValidateSet('Single', 'Multiple', 'Bulk')]
        [string]$OperationScope = 'Single',

        [Parameter()]
        [string]$CorrelationId = [System.Guid]::NewGuid().ToString()
    )

    process {
        try {
            Write-Verbose "Initializing restore operation context - Scope: $OperationScope - CorrelationId: $CorrelationId"

            # Check Active Directory module availability
            $adModuleAvailable = $false
            try {
                Import-Module ActiveDirectory -ErrorAction Stop
                $adModuleAvailable = $true
            }
            catch {
                Write-Warning "Active Directory module not available: $($_.Exception.Message)"
            }

            # Check current user context and permissions
            $currentUser = [System.Security.Principal.WindowsIdentity]::GetCurrent().Name
            $userGroups = ([System.Security.Principal.WindowsIdentity]::GetCurrent()).Groups | ForEach-Object {
                try { $_.Translate([System.Security.Principal.NTAccount]).Value } catch { $_.Value }
            }

            # Prepare operation context
            $context = [PSCustomObject]@{
                PSTypeName = 'RestoreOperationContext'
                OperationScope = $OperationScope
                CurrentUser = $currentUser
                UserGroups = $userGroups
                ADModuleAvailable = $adModuleAvailable
                InitializedAt = Get-Date
                CorrelationId = $CorrelationId
                MemoryUsage = [System.GC]::GetTotalMemory($false)
                ProcessId = $PID
            }

            Write-Verbose "Restore operation context initialized successfully - CorrelationId: $CorrelationId"
            return $context
        }
        catch {
            Write-Error "Failed to initialize restore operation context: $($_.Exception.Message) - CorrelationId: $CorrelationId"
            throw
        }
    }
}


function Complete-RestoreOperation {
    <#
    .SYNOPSIS
        Finalizes restore operation with cleanup and summary reporting.
 
    .DESCRIPTION
        Performs final cleanup, resource disposal, and summary reporting
        for completed restore operations. Ensures proper resource management
        and provides comprehensive operation statistics.
 
    .PARAMETER OperationContext
        Operation context from Start-RestoreOperation.
 
    .PARAMETER Results
        Array of restore workflow results to summarize.
 
    .PARAMETER CorrelationId
        Unique identifier for tracking this operation completion.
 
    .EXAMPLE
        PS> Complete-RestoreOperation -OperationContext $context -Results $results
 
        Finalizes restore operation with cleanup and reporting.
 
    .OUTPUTS
        [PSCustomObject] RestoreOperationSummary
    #>

    [CmdletBinding()]
    [OutputType('RestoreOperationSummary')]
    param(
        [Parameter(Mandatory)]
        [ValidateNotNull()]
        [PSCustomObject]$OperationContext,

        [Parameter()]
        [PSCustomObject[]]$Results = @(),

        [Parameter()]
        [string]$CorrelationId = [System.Guid]::NewGuid().ToString()
    )

    process {
        try {
            Write-Verbose "Finalizing restore operation - CorrelationId: $CorrelationId"

            # Calculate operation statistics
            $totalOperations = $Results.Count
            $successfulOperations = @($Results | Where-Object { $_.Success }).Count
            $failedOperations = $totalOperations - $successfulOperations

            # Calculate timing statistics
            $totalDuration = if ($Results.Count -gt 0) {
                ($Results | Measure-Object -Property Duration -Sum).Sum
            } else {
                [TimeSpan]::Zero
            }

            $averageDuration = if ($Results.Count -gt 0) {
                [TimeSpan]::FromTicks($totalDuration.Ticks / $Results.Count)
            } else {
                [TimeSpan]::Zero
            }

            # Memory usage comparison
            $finalMemoryUsage = [System.GC]::GetTotalMemory($false)
            $memoryDelta = $finalMemoryUsage - $OperationContext.MemoryUsage

            # Cleanup resources
            [System.GC]::Collect()
            [System.GC]::WaitForPendingFinalizers()

            $summary = [PSCustomObject]@{
                PSTypeName = 'RestoreOperationSummary'
                OperationScope = $OperationContext.OperationScope
                TotalOperations = $totalOperations
                SuccessfulOperations = $successfulOperations
                FailedOperations = $failedOperations
                SuccessRate = if ($totalOperations -gt 0) { [math]::Round(($successfulOperations / $totalOperations) * 100, 2) } else { 0 }
                TotalDuration = $totalDuration
                AverageDuration = $averageDuration
                MemoryDelta = $memoryDelta
                CompletedAt = Get-Date
                CorrelationId = $CorrelationId
            }

            Write-Verbose "Restore operation completed - Success Rate: $($summary.SuccessRate)% - CorrelationId: $CorrelationId"
            return $summary
        }
        catch {
            Write-Error "Failed to complete restore operation: $($_.Exception.Message) - CorrelationId: $CorrelationId"
            throw
        }
    }
}


#endregion