using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Security;
using System.Threading;
using BITKit.Apps;
using Cysharp.Threading.Tasks;
using UnityEngine;
using UnityEngine.Events;
using HttpClient = System.Net.Http.HttpClient;
using OperationCanceledException = System.OperationCanceledException;
using UnityWebRequest = UnityEngine.Networking.UnityWebRequest;

namespace BITKit
{
	[Serializable]
	public class UnityApplicationServiceSingleton:IApplicationService
	{
		private IApplicationService _applicationServiceImplementation=>ApplicationService.Singleton;
		
		public event Action<string> OnClientVersionCheck
		{
			add => ApplicationService.OnClientVersionCheck += value;
			remove => ApplicationService.OnClientVersionCheck -= value;
		}

		public event Action<string> OnLatestVersionCheck
		{
			add => ApplicationService.OnLatestVersionCheck += value;
			remove => ApplicationService.OnLatestVersionCheck -= value;
		}

		public event Action<string> OnDownloadLatest
		{
			add => ApplicationService.OnDownloadLatest += value;
			remove => ApplicationService.OnDownloadLatest -= value;
		}

		public event Action<float> OnDownloadProgress
		{
			add => ApplicationService.OnDownloadProgress += value;
			remove => ApplicationService.OnDownloadProgress -= value;
		}

		public event Action<string> OnDownloadComplete
		{
			add => ApplicationService.OnDownloadComplete += value;
			remove => ApplicationService.OnDownloadComplete -= value;
		}

		public event Action OnDetectedLatestVersion;

		public UniTask<string> DownloadLatestVersionAsync()
		{
			return _applicationServiceImplementation.DownloadLatestVersionAsync();
		}

		public string DownloadLatestUrl => _applicationServiceImplementation.DownloadLatestUrl;

		public string CheckLatestVersionUrl => _applicationServiceImplementation.CheckLatestVersionUrl;
	}
	/// <summary>
	/// 用于Unity的应用程序服务,详细功能请查看<see cref="IApplicationService"/>
	/// </summary>
	public class ApplicationService : MonoBehaviour,IApplicationService
	{
		private static readonly HttpClient Client = new();
		public static event Action<string> OnClientVersionCheck;
		public static event Action<string> OnLatestVersionCheck;
		public static event Action<string> OnDownloadLatest;
		public static event Action<float> OnDownloadProgress;
        public static event Action<string> OnDownloadComplete;
		internal static IApplicationService Singleton { get; private set; }
		[SerializeField, SerializeReference, SubclassSelector]
		private IReference getVersionUrl;
		[SerializeField, SerializeReference, SubclassSelector]
		private IReference getLatestUrl;

		[SerializeReference, SubclassSelector] private ITicker checkTick;
		[SerializeField] private bool dontDestroyOnLoad;

		event Action<string> IApplicationService.OnClientVersionCheck
		{
			add => OnClientVersionCheck += value;
			remove => OnClientVersionCheck -= value;
		}
		event Action<string> IApplicationService.OnLatestVersionCheck
		{
			add => OnLatestVersionCheck += value;
			remove => OnLatestVersionCheck -= value;
		}
		event Action<string> IApplicationService.OnDownloadLatest
		{
			add => OnDownloadLatest += value;
			remove => OnDownloadLatest -= value;
		}
		event Action<float> IApplicationService.OnDownloadProgress
		{
			add => OnDownloadProgress += value;
			remove => OnDownloadProgress -= value;
		}
		event Action<string> IApplicationService.OnDownloadComplete
		{
			add => OnDownloadComplete += value;
			remove => OnDownloadComplete -= value;
		}

		public event Action OnDetectedLatestVersion
		{
			add => Singleton.OnDetectedLatestVersion += value;
			remove => Singleton.OnDetectedLatestVersion -= value;
		}

		private UnityWebRequest downloadRequest;

		public async UniTask<string> DownloadLatestVersionAsync()
		{
			var filePath =
				$"{Application.persistentDataPath}/{Application.productName}-Build_{Application.platform}_{Application.version}.";
			switch (Application.platform)
			{
				case RuntimePlatform.Android:
					filePath += "apk";
					break;
				default:
					filePath += "zip";
					break;
			}
			BIT4Log.Log<ApplicationService>($"开始下载最新版本,下载地址:{getLatestUrl.Value},保存路径:{filePath}");
			OnDownloadLatest?.Invoke(getLatestUrl.Value);
			downloadRequest = UnityWebRequest.Get(getLatestUrl.Get());
			downloadRequest.SendWebRequest().ToUniTask().Forget();
			while (downloadRequest.downloadHandler.isDone is false)
			{
				OnDownloadProgress?.Invoke(downloadRequest.downloadProgress);
				destroyCancellationToken.ThrowIfCancellationRequested();
				await UniTask.NextFrame();
			}

			await File.WriteAllBytesAsync(filePath, downloadRequest.downloadHandler.data,destroyCancellationToken);
			OnDownloadComplete?.Invoke(filePath);

			return filePath;
		}

		public string DownloadLatestUrl => getLatestUrl.Value;
		public string CheckLatestVersionUrl=>getVersionUrl.Value;
		private bool _isBusy;

		private void Awake()
		{
			Singleton = this;
		}

		private void Start()
		{
			if (dontDestroyOnLoad)
			{
				DontDestroyOnLoad(gameObject);
			}
			try
			{
				OnTick(0);
			}
			catch(OperationCanceledException){}
			catch (Exception e)
			{
				BIT4Log.LogException(e);
			}

			destroyCancellationToken.Register(Dispose);
			
			checkTick?.Add(OnTick);
		}
		private async void OnTick(float deltaTime)
		{
			if(_isBusy)return;
			try
			{
				var latestVersion = await Client.GetStringAsync(getVersionUrl.Value);
				if (destroyCancellationToken.IsCancellationRequested) return;

				var currentVersion = Application.version;

				OnClientVersionCheck?.Invoke(currentVersion);
				OnLatestVersionCheck?.Invoke(latestVersion);
			}
			catch (OperationCanceledException)
			{
			}
			catch (Exception e)
			{
				BIT4Log.LogException(e);
			}
			_isBusy = false;
		}
		private void Dispose()
		{
			checkTick?.Remove(OnTick);
			downloadRequest?.Abort();
		}
	}

}