# Function to update a list of paths
Function Update-ListOfPaths {
    param([System.Collections.ArrayList]$List,[string]$Path)
    If ( $List -inotcontains $Path ) { $List.Add($Path) | Out-Null }
}

# Function to expand the UserProfile environment variable as used by MSP360, and update $List
Function Add-UserProfilePaths {
    param([System.Collections.ArrayList]$List,[string]$Path)

    $ChildPath = ($Path -split '%')[2]

    # Get a list of all user profile directories
    ForEach ( $profile in (Get-ChildItem -Path 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList') ) {
        $profileImagePath = Get-ItemPropertyValue -Path $([System.Environment]::ExpandEnvironmentVariables($profile.PSPath)) -Name ProfileImagePath

        # Skip profiles located outside C:\Users as MSP360 doesn't currently include these when using the %UserProfile% variable
        If ( !($profileImagePath -ilike "*${Env:SystemDrive}\Users\*") ) { Continue }

        # Build the path we're trying to add
        $path = Join-Path -Path $profileImagePath -ChildPath $ChildPath
        
        # Skip adding the path if it doesn't exist
        If ( !(Test-Path $path) ) { Continue }

        # Add the path
        Update-ListOfPaths -List $List -Path $path
    }
}

Function Use-Path {
    param([System.Collections.ArrayList]$List,[string]$Path)
    Switch ( $Path ) {
        { $_ -ilike '*%UserProfile%*' } { Add-UserProfilePaths -List $List -Path $Path }
        { $_ -ilike '*%*%*' } { Update-ListOfPaths -List $List -Path $([System.Environment]::ExpandEnvironmentVariables($Path)) }
        default { Update-ListOfPaths -List $List -Path $Path }
    }
}

# Import MSP360 module
Import-MSP360Module

# Get all backup plans
$BackupPlans = Get-MBSBackupPlan -OutputType Raw

# Track the number of processed backup plans so we can put line breaks between them in the output
$planIter = 0

# Iterate over all backup plans
ForEach ( $plan in $BackupPlans ) {

    # Add a line break in the output if we've already processed a backup plan
    If ( $planIter -gt 0 ) { Write-Output "`n" }

    # Function to process each file
    Function ProcessFile {
        param([System.IO.FileInfo]$File)

        Switch ( $File ) {

            # Filter out if name matches an excluded path
            { $null -ne ($ExcludedPaths | Where-Object { $File.FullName.Replace('\','\\') -match $_.Replace('\','\\') }) } { Update-FilteredFiles $File }

            # Filter out if file size is greater than plan maximum
            { $File.Length -gt $MaxFileSize } { Update-FilteredFiles $File }

            # Add item to $IncludeFiles
            default { $IncludedFiles.Add($item.FullName, $item.Length) | Out-Null }
        }
    }

    # Function to add a file to $FilteredFiles
    Function Update-FilteredFiles {
        param([System.IO.FileInfo]$File)
        $FilteredFiles.Add($File.FullName, $File.Length) | Out-Null
    }

    # Print the plan name that we're currently working on
    Write-Output ('Plan Name: {0}' -f ($plan.Name))

    # Create array lists to store paths included in the plans
    [System.Collections.ArrayList]$IncludedPaths = @()
    [System.Collections.ArrayList]$ExcludedPaths = @()

    # Create array lists to keep files matching certain patterns
    [System.Collections.Hashtable]$FilteredFiles = @{}
    [System.Collections.Hashtable]$IncludedFiles = @{}

    # Get all included items from plan
    If ( $null -ne $plan.Items ) {
        ForEach ( $obj in $plan.Items ) {
            ForEach ( $path in $obj.PlanItem.Path ) {
                Use-Path -List $IncludedPaths -Path $path
            }
        }
    }

    # Get all excluded items from plan
    If ( $null -ne $plan.ExcludedItems ) {
        ForEach ( $obj in $plan.ExcludedItems ) {
            ForEach ( $path in $obj.PlanItem.Path ) {
                Use-Path -List $ExcludedPaths -Path $path
            }
        }
    }

    # Print all paths in $IncludedPaths
    If ( $IncludedPaths.Length -gt 0 ) {
        Write-Output "Paths to backup:"
        ForEach ( $path in ($IncludedPaths | Sort-Object) ) { Write-Output $path }
    }

    # Define $MaxFileSize if it exists, or set it to the default value if it can't be obtained
    If ( $null -ne $plan.MaxFileSize ) { $MaxFileSize = $plan.MaxFileSize } Else { $MaxFileSize = [long]::MaxValue }

    # Process each path in $IncludedPaths
    ForEach ($path in $IncludedPaths ) {

        # Skip paths that don't exist
        If ( !(Test-Path $path) ) { Continue }

        # If $path is an individual file, process it separately
        $item = Get-Item -Path $path -ErrorAction SilentlyContinue
        If ( $item -is [System.IO.FileInfo] ) { ProcessFile $item ; Continue }

        # Get all children of $path
        ForEach ( $item in (Get-ChildItem -Path $path -Recurse -Force -ErrorAction SilentlyContinue) ) {

            # Process each file
            If ( $item -is [System.IO.FileInfo] ) { ProcessFile $item }
        }
    }

    # Print total files and total size
    Write-Output ('Total Files: {0}' -f ($IncludedFiles.Count))
    If ( $IncludedFiles.Count -gt 0 ) {
        $IncludedFilesSize = 0
        ForEach ($len in $IncludedFiles.Values) { $IncludedFilesSize += $len}
        Write-Output $('Total size: {0}GB' -f [math]::Round(($IncludedFilesSize/1GB),2) )
    }

    # Print total excluded files and, optionally, the total size of excluded files as well as their full path
    Write-Output ('Total Excluded Files: {0}' -f ($FilteredFiles.Count))
    If ( $FilteredFiles.Count -gt 0 ) {
        $FilteredFilesSize = 0
        ForEach ($len in $FilteredFiles.Values) { $FilteredFilesSize += $len}
        Write-Output $('Total size: {0}GB' -f [math]::Round(($FilteredFilesSize/1GB),2) )
        Write-Output "All files excluded from plan:"
        ForEach ($file in $FilteredFiles.GetEnumerator()) {
            Write-Output $file.Name
        }
    }
    $planIter++
}