DLL Version Comparison

[CmdletBinding()]
param(
    [Parameter(Mandatory = $true)]
    [string]$Folder1,

    [Parameter(Mandatory = $true)]
    [string]$Folder2,

    [Parameter(Mandatory = $false)]
    [switch]$IncludeSubfolders = $false
)

function Get-DllVersions {
    param(
        [string]$FolderPath,
        [bool]$Recurse
    )

    if (-not (Test-Path $FolderPath)) {
        Write-Error "Folder path '$FolderPath' does not exist."
        return @{}
    }

    $dllFiles = Get-ChildItem -Path $FolderPath -Filter "*.dll" -Recurse:$Recurse

    $dllVersions = @{}

    foreach ($dll in $dllFiles) {
        try {
            $versionInfo = [System.Diagnostics.FileVersionInfo]::GetVersionInfo($dll.FullName)
            $relativePath = $dll.FullName.Replace($FolderPath, "").TrimStart('\')

            $dllVersions[$relativePath] = @{
                FileVersion    = $versionInfo.FileVersion
                ProductVersion = $versionInfo.ProductVersion
                FullPath       = $dll.FullName
            }
        }
        catch {
            Write-Warning "Could not get version info for: $($dll.FullName) - $($_.Exception.Message)"
            $dllVersions[$relativePath] = @{
                FileVersion    = "Unable to read"
                ProductVersion = "Unable to read"
                FullPath       = $dll.FullName
            }
        }
    }

    return $dllVersions
}

function Compare-DllVersions {
    param(
        [hashtable]$Folder1Dlls,
        [hashtable]$Folder2Dlls,
        [string]$Folder1Name,
        [string]$Folder2Name
    )

    $differences = @()

    # Get all unique DLL names from both folders
    $allDlls = @($Folder1Dlls.Keys) + @($Folder2Dlls.Keys) | Sort-Object -Unique

    foreach ($dllName in $allDlls) {
        $dll1 = $Folder1Dlls[$dllName]
        $dll2 = $Folder2Dlls[$dllName]

        if ($null -eq $dll1) {
            # DLL only exists in Folder2
            $differences += [PSCustomObject]@{
                DllName             = $dllName
                Status              = "Only in $Folder2Name"
                Folder1_FileVersion = "N/A"
                Folder2_FileVersion = $dll2.FileVersion
            }
        }
        elseif ($null -eq $dll2) {
            # DLL only exists in Folder1
            $differences += [PSCustomObject]@{
                DllName             = $dllName
                Status              = "Only in $Folder1Name"
                Folder1_FileVersion = $dll1.FileVersion
                Folder2_FileVersion = "N/A"
            }
        }
        else {
            if ($dll1.FileVersion -ne $dll2.FileVersion) {
                $differences += [PSCustomObject]@{
                    DllName             = $dllName
                    Status              = "File Version Diff"
                    Folder1_FileVersion = $dll1.FileVersion
                    Folder2_FileVersion = $dll2.FileVersion
                }
            }
        }
    }

    return $differences
}

$Folder1 = $Folder1 | Resolve-Path
$Folder2 = $Folder2 | Resolve-Path

# Main script execution
Write-Host "Comparing DLL versions between folders..." -ForegroundColor Green
Write-Host "Folder 1: $Folder1" -ForegroundColor Cyan
Write-Host "Folder 2: $Folder2" -ForegroundColor Cyan
Write-Host "Include Subfolders: $IncludeSubfolders" -ForegroundColor Cyan
Write-Host ""

# Get DLL versions from both folders
Write-Host "Scanning Folder 1..." -ForegroundColor Yellow
$folder1Dlls = Get-DllVersions -FolderPath $Folder1 -Recurse $IncludeSubfolders

Write-Host "Scanning Folder 2..." -ForegroundColor Yellow
$folder2Dlls = Get-DllVersions -FolderPath $Folder2 -Recurse $IncludeSubfolders

Write-Host "Found $($folder1Dlls.Count) DLLs in Folder 1" -ForegroundColor Magenta
Write-Host "Found $($folder2Dlls.Count) DLLs in Folder 2" -ForegroundColor Magenta
Write-Host ""

# Compare the versions
$differences = Compare-DllVersions -Folder1Dlls $folder1Dlls -Folder2Dlls $folder2Dlls -Folder1Name "Folder1" -Folder2Name "Folder2"

if ($differences.Count -eq 0) {
    Write-Host "No differences found between the DLL versions in both folders!" -ForegroundColor Green
}
else {
    Write-Host "Found $($differences.Count) differences:" -ForegroundColor Red
    Write-Host ""

    # Display the differences in a formatted table
    $differences | Format-Table -AutoSize -Wrap
}

Write-Host ""
Write-Host "Comparison complete!" -ForegroundColor Green