Moves video files under folders to the upper level and adopts the folder name.

move-media-to-folder-level.ps1

# Moves video files under folders to the upper level and adopts the folder name. 
# for example FolderA\FileA.mp4 => FolderA.mp4
# duplicates will append a number, FolderA_<1-100>.mp4, max 100 files can be moved to the upper level.
#
# Use cases:
# - Movie folders with the movie inside
# - Single Album Covers with single or multiple of the same cover.
#
# Check if the first argument is a folder; otherwise, prompt for a folder
# Check if the first argument exists and is a folder; if so, use it as the base directory
# Use WPF Open Directory Dialog instead of WinForms
Add-Type -AssemblyName PresentationFramework

function Select-FolderDialogWPF {
    $dialog = New-Object Microsoft.Win32.OpenFileDialog
    $dialog.CheckFileExists = $false
    $dialog.FileName = "Select Folder"
    $dialog.ValidateNames = $false
    $dialog.Filter = "Folders|."
    if ($dialog.ShowDialog() -eq $true) {
        return ([System.IO.Path]::GetDirectoryName($dialog.FileName))
    } else {
        return $null
    }
}

if ($args.Count -gt 0 -and (Test-Path $args[0] -PathType Container)) {
    $baseDir = $args[0]
} else {
    $baseDir = Select-FolderDialogWPF
    if (-not $baseDir) {
        Write-Host "No folder selected. Exiting." -ForegroundColor Red
        exit
    }
}

function Exit-WithAnyKey {
    Write-Host "Press any key to exit..."
    [void][System.Console]::ReadKey($true)
    exit
}

if ($baseDir -like "C:\Windows*" -or (Resolve-Path $baseDir).ProviderPath -like "C:\Windows*") {
    Write-Host "Error: The selected base directory is inside C:\Windows. Exiting for safety." -ForegroundColor Red
    Exit-WithAnyKey
}

# Check for dry-run parameter
$dryRun = $false
if ($args -contains "-dry" -or $args -contains "--dry-run" -or $args -contains "-d") {
    $dryRun = $true
    Write-Host "DRY RUN MODE - No files will be moved" -ForegroundColor Yellow
    Write-Host ""
}

# Get all subfolders in the base directory
$folders = Get-ChildItem -Path $baseDir -Directory

Write-Host "Processing folders in: $baseDir" -ForegroundColor Cyan
Write-Host ""

foreach ($folder in $folders) {
    Write-Host "Processing folder: $($folder.Name)" -ForegroundColor Green
    
    # Get all .mp4 and .mkv files in the folder
    $mediaFiles = Get-ChildItem -Path $folder.FullName -File | Where-Object { $_.Name -match '\.(mp4|mkv)$' }
    foreach ($mediaFile in $mediaFiles) {
        $ext = $mediaFile.Extension
        $newBaseName = $folder.Name
        $newName = "$newBaseName$ext"

        # Check for duplicates and append _<number> if needed, try up to 100 times
        $baseNameOnly = [System.IO.Path]::GetFileNameWithoutExtension($folder.Name)
        $tryName = "$baseNameOnly$ext"
        $counter = 1
        while ((Test-Path (Join-Path -Path $baseDir -ChildPath $tryName)) -and ($counter -le 100)) {
            $tryName = "${baseNameOnly}_$counter$ext"
            $counter++
        }
        $newName = $tryName

        $destPath = Join-Path -Path $baseDir -ChildPath $newName
        
        if ($dryRun) {
            Write-Host "  Would move: $($mediaFile.Name) -> $newName" -ForegroundColor White
            Write-Host "    From: $($mediaFile.FullName)" -ForegroundColor Gray
            Write-Host "    To:   $destPath" -ForegroundColor Gray
        } else {
            Write-Host "  Moving: $($mediaFile.Name) -> $newName" -ForegroundColor White
            Move-Item -Path $mediaFile.FullName -Destination $destPath -Force
        }
        Write-Host ""
    }
}

if ($dryRun) {
    Write-Host "DRY RUN COMPLETE - No files were moved" -ForegroundColor Yellow
    Write-Host "Run the script without -dry, --dry-run, or -d to actually move the files" -ForegroundColor Cyan
    Exit-WithAnyKey
} else {
    Write-Host "File conversion complete!" -ForegroundColor Green
    Exit-WithAnyKey
}