using IBKRTrader.Core.Database;
using IBKRTrader.Core.Logging;
using IBKRTrader.Core.Settings;

namespace IBKRTrader.Core.Workers.BuiltIn;

/// <summary>
/// BackupWorker (Core) – läuft alle 30 Minuten (konfigurierbar).
/// 1. Ruft mysqldump.exe auf → SQL-Dump in Backups\DB\
/// 2. Kopiert Logs\ → Backups\Logs\
/// Falls mysqldump nicht gefunden: Warnung und Überspringen.
/// </summary>
public class BackupWorker : WorkerBase
{
    private readonly SettingsService _settings;

    public override string     Name   => "BackupWorker";
    public override string     Module => "Core";
    public override WorkerType Type   => WorkerType.Worker;

    protected override TimeSpan? Interval =>
        TimeSpan.FromMinutes(_settings.Settings.WorkerSettings.BackupWorker.IntervalMinutes);

    public BackupWorker(LoggingService logger, DatabaseService db, SettingsService settings)
        : base(logger, db)
    {
        _settings = settings;
        Info.Active = settings.Settings.WorkerSettings.BackupWorker.Enabled;
    }

    protected override async Task ExecuteAsync(CancellationToken ct)
    {
        var timestamp  = DateTime.Now.ToString("yyyy-MM-dd_HH-mm");
        var backupRoot = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Backups");
        var dbDir      = Path.Combine(backupRoot, "DB");
        var logsDir    = Path.Combine(backupRoot, "Logs");

        Directory.CreateDirectory(dbDir);
        Directory.CreateDirectory(logsDir);

        // ── 1. Datenbank-Dump ────────────────────────────────────────────────
        await RunMysqlDumpAsync(dbDir, timestamp, ct);

        // ── 2. Logs-Backup ───────────────────────────────────────────────────
        CopyLogs(logsDir, timestamp);

        Logger.Info(Module, $"Backup abgeschlossen: {timestamp}");
    }

    // ─── mysqldump ────────────────────────────────────────────────────────────

    private async Task RunMysqlDumpAsync(string dbDir, string timestamp, CancellationToken ct)
    {
        var dump = FindMysqldump();
        if (dump == null)
        {
            Logger.Warn(Module, "mysqldump.exe nicht gefunden – DB-Backup übersprungen.");
            return;
        }

        var db       = _settings.Settings.Database;
        var dumpFile = Path.Combine(dbDir, $"{db.Database}_{timestamp}.sql");

        var args = $"--host={db.Host} --port={db.Port} " +
                   $"--user={db.User} --password={db.Password} " +
                   $"--single-transaction --routines --triggers " +
                   $"{db.Database} --result-file=\"{dumpFile}\"";

        var psi = new System.Diagnostics.ProcessStartInfo
        {
            FileName               = dump,
            Arguments              = args,
            RedirectStandardError  = true,
            UseShellExecute        = false,
            CreateNoWindow         = true
        };

        using var proc = System.Diagnostics.Process.Start(psi)
            ?? throw new InvalidOperationException("mysqldump konnte nicht gestartet werden.");

        await proc.WaitForExitAsync(ct);

        if (proc.ExitCode != 0)
        {
            var err = await proc.StandardError.ReadToEndAsync(ct);
            Logger.Warn(Module, $"mysqldump Exitcode {proc.ExitCode}: {err}");
        }
        else
        {
            Logger.Info(Module, $"DB-Dump erstellt: {Path.GetFileName(dumpFile)}");
        }
    }

    private static string? FindMysqldump()
    {
        // Häufige Installationspfade auf Windows-Server
        var candidates = new[]
        {
            "mysqldump.exe",
            @"C:\Program Files\MySQL\MySQL Server 8.0\bin\mysqldump.exe",
            @"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqldump.exe",
            @"C:\xampp\mysql\bin\mysqldump.exe"
        };

        foreach (var c in candidates)
            if (File.Exists(c)) return c;

        // PATH-Suche
        var pathVar = Environment.GetEnvironmentVariable("PATH") ?? "";
        foreach (var dir in pathVar.Split(';'))
        {
            var full = Path.Combine(dir.Trim(), "mysqldump.exe");
            if (File.Exists(full)) return full;
        }

        return null;
    }

    // ─── Logs kopieren ────────────────────────────────────────────────────────

    private void CopyLogs(string logsBackupDir, string timestamp)
    {
        try
        {
            var srcLogs = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Logs");
            if (!Directory.Exists(srcLogs)) return;

            var destDir = Path.Combine(logsBackupDir, timestamp);
            CopyDirectory(srcLogs, destDir);
            Logger.Info(Module, $"Logs-Backup erstellt: {destDir}");
        }
        catch (Exception ex)
        {
            Logger.Warn(Module, $"Logs-Backup fehlgeschlagen: {ex.Message}");
        }
    }

    private static void CopyDirectory(string src, string dest)
    {
        Directory.CreateDirectory(dest);
        foreach (var file in Directory.GetFiles(src))
            File.Copy(file, Path.Combine(dest, Path.GetFileName(file)), overwrite: true);
        foreach (var dir in Directory.GetDirectories(src))
            CopyDirectory(dir, Path.Combine(dest, Path.GetFileName(dir)));
    }
}