using System;
using System.Collections;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IO;
using System.Threading;

#if UNITY_WINDOW
using AnotherFileBrowser.Windows;
#endif
#if UNITY_5_3_OR_NEWER
using UnityEngine;
#endif

using Cysharp.Threading.Tasks;



namespace BITKit.IO
{
	public interface IApplicationFile
	{
        string Extension { get; set; }
        string Current { get; }
		event Func<(string, byte[])> DataHandle;
		event Action<string, string> OnPathChanged;
		void Save();
		void SaveAs(string path=null);
		void Load(string file=null);
		void Reload();
		void AddListener(string key, Action<byte[]> action);
		void RemoveListener(string key, Action<byte[]> action);
	}
	#if UNITY_WINDOW
	[Serializable]
	public sealed class ApplicationFile:IApplicationFile
	{
		private const string DefaultPath = nameof(ApplicationFile)+"."+nameof(DefaultPath);
		
		#if UNITY_5_3_OR_NEWER
		[UnityEngine.RuntimeInitializeOnLoadMethod]
		private static void Reload()
		{
			Current = null;
			DataHandle = null;
			_genericEvent.Clear();
			_OpenFileCancellationTokenSource = new();
		}
		#endif
		public static IStorageFile Current
		{
			get => _current;
			set
			{
				OnPathChanged?.Invoke(_current,value);
				_current = value;
			}
		}

		private static IStorageFile _current;
		public static event Func<(string, byte[])> DataHandle;
		public static event Action<IStorageFile, IStorageFile> OnPathChanged;
		private static readonly GenericEvent _genericEvent = new();
		private static CancellationTokenSource _OpenFileCancellationTokenSource = new();
		private static string Extension { get; set; } = "zip";

		private static BrowserProperties _browserProperties
		{
			get
			{
				var bp = new BrowserProperties();
				#if UNITY_5_3_OR_NEWER
				if (PlayerPrefs.HasKey(DefaultPath))
				{
					bp.initialDir = PlayerPrefs.GetString(DefaultPath);
				}
				#endif
				if (string.IsNullOrEmpty(Extension) is false)
				{
					bp.filter = $"{Extension} files (*.{Extension})|*.{Extension}";
				}
				return bp;
			}
		}

		public static void Save()
		{
			if (Current is null)
			{
				var bp = _browserProperties;
			
				new Thread(() =>
				{
					new FileBrowser().SaveFileBrowser(bp, nameof(ApplicationFile), $".{Extension}", async path =>
					{
						await BITApp.SwitchToMainThread();

						Current = new FileProvider(path);
						
						Save();
					});
				}).Start();
				
				BIT4Log.Log<IApplicationFile>($"无已加载的数据,等待选择保存地址");
				return;
			}

			if (DataHandle is null)
			{
				BIT4Log.Log<IApplicationFile>("无任何可保存的数据");
			}

			List<IAsset> assets = new();
			foreach (var func in DataHandle.CastAsFunc())
			{	
				(string name,byte[] bytes) value = func.Invoke();
				var asset = new BITAsset(value.name,value.bytes);
				assets.Add(asset);
			}
			BITAssets.Build(Current.GetPath(),assets.ToArray());
			
			BIT4Log.Log<IApplicationFile>($"已保存为:{Current.GetPath()}");
		}

		public static async void SaveAs(string path)
		{
			if (path is null)
			{
				var bp = _browserProperties;
			
				new Thread(() =>
				{
					new FileBrowser().SaveFileBrowser(bp, nameof(ApplicationFile), $".{Extension}", async path =>
					{
						await BITApp.SwitchToMainThread();

						Current = new FileProvider(path);
						
						SaveAs(path);
					});
				}).Start();
				
				return;
			}
			Current = new FileProvider(path);
			Save();
		}
		public void AddListener(string key, Action<byte[]> action)
		{
			_genericEvent.AddListener<byte[]>(key,action);
		}

		public void RemoveListener(string key, Action<byte[]> action)
		{
			_genericEvent.RemoveListener<byte[]>(key,action);
		}

		public static void ReloadFile()
		{
			Load(Current);
		}
		public static void Load(IStorageFile file=null)
		{
			if (file is null)
			{
				_OpenFileCancellationTokenSource.Cancel();
				_OpenFileCancellationTokenSource = new();
				
				BIT4Log.Log<IApplicationFile>("正在选择文件,跳过该次载入");

				var bp = _browserProperties;
				new Thread(() =>
				{
					new FileBrowser().OpenFileBrowser(bp, Filepath);
					return;
					async void Filepath(string path)
					{
						await BITApp.SwitchToMainThread();
						Current = new FileProvider(path);
						Load(Current);
					}
				}).Start();
				
				return;
			}

			Current = file;

			var path = file.GetPath();
			var header = BITAssets.ReadHeader(path);
			foreach (var name in header.Files)
			{
				var asset = BITAssets.ReadAsset(path, name);
				
				_genericEvent.Invoke(asset.Name,asset.Buffer);
			}
			BIT4Log.Log<IApplicationFile>($"已加载{header.Files.Count}个数据");
		}
		string IApplicationFile.Extension
		{
			get => Extension;
			set => Extension = value;
		}
		IStorageFile IApplicationFile.Current => Current;
		
        event Func<(string, byte[])> IApplicationFile.DataHandle
        {
	        add => DataHandle += value;
	        remove => DataHandle -= value;
        }
        event Action<IStorageFile,IStorageFile> IApplicationFile.OnPathChanged
        {
	        add => OnPathChanged += value;
	        remove=>OnPathChanged -= value;
        }

      

        void IApplicationFile.Save() => Save();

		void IApplicationFile.SaveAs(string path) => SaveAs(path);

		void IApplicationFile.Load(IStorageFile file) => Load(file);
		void IApplicationFile.Reload()=>ReloadFile();

	}
#endif
}