/*   
TShock, a server mod for Terraria
Copyright (C) 2011 The TShock Team

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/


using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading;
using Terraria;

namespace TShockAPI
{
    public class BackupManager
    {
        public string BackupPath { get; set; }
        public int Interval { get; set; }
        public int KeepFor { get; set; }

        DateTime lastbackup = DateTime.UtcNow;
        public BackupManager(string path)
        {
            BackupPath = path;
        }

        public bool IsBackupTime
        {
            get
            {
                return (Interval > 0) && ((DateTime.UtcNow - lastbackup).TotalMinutes >= Interval);
            }
        }

        public void Backup()
        {
            lastbackup = DateTime.UtcNow;
            ThreadPool.QueueUserWorkItem(DoBackup);
            ThreadPool.QueueUserWorkItem(DeleteOld);
        }

        void DoBackup(object o)
        {
            try
            {
                string worldname = Main.worldPathName;
                string name = Path.GetFileName(worldname);

                Main.worldPathName = Path.Combine(BackupPath, string.Format("{0}.{1:dd.MM.yy-HH.mm.ss}.bak", name, DateTime.UtcNow));

                string worldpath = Path.GetDirectoryName(Main.worldPathName);
                if (worldpath != null && !Directory.Exists(worldpath))
                    Directory.CreateDirectory(worldpath);

                Tools.Broadcast("Server map saving, potential lag spike");
                Thread SaveWorld = new Thread(Tools.SaveWorld);
                SaveWorld.Start();

                Main.worldPathName = worldname;
            }
            catch (Exception ex)
            {
                Console.WriteLine("Backup failed");
                Log.Error("Backup failed");
                Log.Error(ex.ToString());
            }
        }

        void DeleteOld(object o)
        {
             if (KeepFor <= 0)
                return;
            foreach (var fi in new DirectoryInfo(BackupPath).GetFiles("*.bak"))
            {
                if ((DateTime.UtcNow - fi.LastWriteTimeUtc).TotalMinutes > KeepFor)
                {
                    fi.Delete();
                }
            }
        }
    }
}