param(
    [string]$BackupFolder = "C:\YEDEK\Sql_bak_files",
    [string]$SQLInstance = "localhost"
)

Write-Host "=== SQL AUTO RESTORE SCRIPT ===" -ForegroundColor Cyan

# .bak dosyalarını al
$bakFiles = Get-ChildItem -Path $BackupFolder -Filter *.bak

foreach ($bak in $bakFiles) {

    Write-Host "`nProcessing file: $($bak.Name)" -ForegroundColor Yellow

    # --- ORJINAL DATABASE ADINI ÇIKAR ---
    $fileBase = [System.IO.Path]::GetFileNameWithoutExtension($bak)
    $parts = $fileBase.Split("_")

    if ($parts.Count -gt 1) {
        $DBName = ($parts[0..($parts.Count - 2)] -join "_")
    } else {
        $DBName = $fileBase
    }

    Write-Host "Detected DB Name: $DBName" -ForegroundColor Green

    # --- DATABASE VAR MI KONTROL ET ---
    $dbExists = Invoke-Sqlcmd -ServerInstance $SQLInstance `
        -Query "SELECT COUNT(*) AS C FROM sys.databases WHERE name = '$DBName'" |
        Select-Object -ExpandProperty C

    if ($dbExists -eq 1) {
        $response = Read-Host "Database '$DBName' mevcut. DROP edilsin mi? (E/H)"

        if ($response -eq "E") {
            Write-Host "Dropping $DBName..." -ForegroundColor Red
            Invoke-Sqlcmd -ServerInstance $SQLInstance `
             -Query "ALTER DATABASE [$DBName] SET SINGLE_USER WITH ROLLBACK IMMEDIATE; DROP DATABASE [$DBName];"
        }
        else {
            Write-Host "DROP atlandı." -ForegroundColor DarkGray
        }
    }
    else {
        Write-Host "Database mevcut değil, DROP sorulmadı." -ForegroundColor DarkGray
    }

    # --- RESTORE FILELISTONLY ---
    $fileList = Invoke-Sqlcmd -ServerInstance $SQLInstance `
        -Query "RESTORE FILELISTONLY FROM DISK = '$($bak.FullName)'"

    $logicalData = ($fileList | Where-Object { $_.Type -eq "D" }).LogicalName
    $logicalLog  = ($fileList | Where-Object { $_.Type -eq "L" }).LogicalName

    # --- KLASÖR OLUŞTUR ---
    $targetFolder = "C:\Mikro\v17xx\$DBName"

    if (!(Test-Path $targetFolder)) {
        New-Item -ItemType Directory -Path $targetFolder | Out-Null
    }

    $newMdf = "$targetFolder\$DBName._MS"
    $newLdf = "$targetFolder\${DBName}_log.ldf"

    Write-Host "Restoring to:" $targetFolder -ForegroundColor Cyan

    # --- RESTORE COMMAND ---
    $restoreQuery = @"
RESTORE DATABASE [$DBName]
FROM DISK = '$($bak.FullName)'
WITH MOVE '$logicalData' TO '$newMdf',
     MOVE '$logicalLog'  TO '$newLdf',
     REPLACE, RECOVERY;
"@

    try {
        Invoke-Sqlcmd -ServerInstance $SQLInstance -Query $restoreQuery
        Write-Host "SUCCESS: $DBName restored." -ForegroundColor Green
    }
    catch {
        Write-Host "ERROR restoring $DBName" -ForegroundColor Red
        Write-Host $_
    }
}

Write-Host "`nCompleted."