using UnityEngine;
using UnityEditor;
using System;
using System.Text.RegularExpressions;
using System.IO;
using System.Collections.Generic;
using System.Linq;

/*
 * MultiAutoSave
 *
 * Autosaves scene at different intervals while keeping a maximum number of files per interval
 *
 * Author: Eneko Castresana Vara
 * Based on AutoSave by Melle Heeres
 *
 * By using this script you understand and acknowledge no warranties of any kind are provided
 * and if you'll sue me you'll burn in hell
*/
public class MultiAutoSave : EditorWindow {

    private class Periodicity {
        public int periodMinutes;
        public int maxFiles;
        public DateTime lastSaveTime;

        public Periodicity(int periodMinutes, int maxFiles) {
            this.periodMinutes=periodMinutes;
            this.maxFiles=maxFiles;
            this.lastSaveTime=DateTime.Now;
        }
    }

    private bool enabled = true;
    private bool showMessage = true;

    private string projectPath;
    private string scenePath;

    private List<Periodicity> periodicities = new List<Periodicity> ();
    private Vector2 scrollPosition=new Vector2(0,0);

    private bool firstRunActions=true;

    [MenuItem ("Window/MultiAutoSave")]
    static void Init () {
        MultiAutoSave saveWindow = (MultiAutoSave)EditorWindow.GetWindow (typeof (MultiAutoSave));
        saveWindow.Show();
    }

    void OnEnable () {
        projectPath = Application.dataPath;
        scenePath = EditorApplication.currentScene;

        //Set up a sensible choice of default periodicities
        periodicities.Add(new Periodicity(1, 5));
        periodicities.Add(new Periodicity(10, 3));
        periodicities.Add(new Periodicity(60, 12));
    }

    void OnGUI () {
        GUILayout.Label ("Info:", EditorStyles.boldLabel);
        EditorGUILayout.LabelField ("Saving to:", ""+projectPath);
        EditorGUILayout.LabelField ("Saving scene:", ""+scenePath);
        GUILayout.Label ("Options:", EditorStyles.boldLabel);
        enabled = EditorGUILayout.BeginToggleGroup ("Enabled", enabled);
        EditorGUILayout.EndToggleGroup();
        showMessage = EditorGUILayout.BeginToggleGroup ("Show Message", showMessage);
        EditorGUILayout.EndToggleGroup ();

        if (GUILayout.Button ("+")) {
            periodicities.Add (new Periodicity (1, 1));
            //Save from the very beginning
            saveScene (periodicities.Last());
        }

        scrollPosition=EditorGUILayout.BeginScrollView (scrollPosition);
        foreach (Periodicity p in periodicities.ToList()) {
            GUILayout.Label ("Periodicity:", EditorStyles.boldLabel);
            p.periodMinutes = EditorGUILayout.IntSlider ("Interval (minutes)", p.periodMinutes, 1, 1440);
            p.maxFiles = EditorGUILayout.IntSlider ("Max files", p.maxFiles, 1, 100);
            EditorGUILayout.LabelField ("Last save:", ""+p.lastSaveTime);
            if (GUILayout.Button ("Remove"))
                periodicities.Remove (p);
            EditorGUILayout.Separator ();
        }
        EditorGUILayout.EndScrollView ();
    }


    void Update(){
        if (!enabled)
            return;

        if (firstRunActions) {
            firstRunActions = false;
            //Save from the very beginning (Needs to be done here)
            foreach (Periodicity p in periodicities)
                saveScene (p);
        }

        DateTime now = DateTime.Now;
        foreach (Periodicity p in periodicities)
            if (now > p.lastSaveTime.AddMinutes (p.periodMinutes))
                saveScene (p);
    }

    void saveScene(Periodicity p) {
        scenePath = EditorApplication.currentScene;
        GroupCollection groups=Regex.Match (scenePath, @"(.*[/\\])(.+)\.unity$").Groups;
        string sceneDryPath = groups [1].Value;
        string sceneDryName = groups [2].Value;

        p.lastSaveTime = DateTime.Now;
        string timeTag=p.lastSaveTime.ToString("yyyy_MM_dd_HH_mm");

        string fileName = sceneDryPath + sceneDryName + "-autosave-"+p.periodMinutes+ "m-" + timeTag + ".unity";

        if (showMessage)
            Debug.Log ("Now saving "+fileName);

        EditorApplication.SaveScene(fileName, true);

        deleteOldFiles (p, sceneDryPath, sceneDryName);

        MultiAutoSave repaintSaveWindow = (MultiAutoSave)EditorWindow.GetWindow (typeof (MultiAutoSave));
        repaintSaveWindow.Repaint();

    }

    void deleteOldFiles (Periodicity p, string sceneDryPath, string sceneDryName) {
        List<FileInfo> files=new List<FileInfo>();
        foreach (string fileName in Directory.GetFiles(sceneDryPath, sceneDryName+"-autosave-"+p.periodMinutes+"m-*.unity*"))
            files.Add (new FileInfo (fileName));
        files.Sort((a, b) => DateTime.Compare(a.LastWriteTime, b.LastWriteTime));

        //This should work assuming both .unity and .unity.meta files are always saved
        for (int i = 0; i < files.Count - p.maxFiles * 2; i++) {
            if (showMessage)
                Debug.Log ("Deleting old file "+files[i].FullName);
            files [i].Delete ();
        }
    }
}