//------------------------------------------------------------
// Game Framework
// Copyright © 2013-2019 Jiang Yin. All rights reserved.
// Homepage: http://gameframework.cn/
// Feedback: mailto:jiangyin@gameframework.cn
//------------------------------------------------------------

using GameFramework.Resource;
using System;
using UnityEngine;
#if UNITY_5_4_OR_NEWER
using UnityEngine.Networking;
#endif
using UnityEngine.SceneManagement;
using Utility = GameFramework.Utility;

namespace UnityGameFramework.Runtime
{
 /// <summary>
 /// 默认加载资源代理辅助器。
 /// </summary>
 public class DefaultLoadResourceAgentHelper : LoadResourceAgentHelperBase, IDisposable
 {
 private string m_FileFullPath = null;
 private string m_BytesFullPath = null;
 private int m_LoadType = 0;
 private string m_AssetName = null;
 private float m_LastProgress = 0f;
 private bool m_Disposed = false;
#if UNITY_5_4_OR_NEWER
 private UnityWebRequest m_UnityWebRequest = null;
#else
 private WWW m_WWW = null;
#endif
 private AssetBundleCreateRequest m_FileAssetBundleCreateRequest = null;
 private AssetBundleCreateRequest m_BytesAssetBundleCreateRequest = null;
 private AssetBundleRequest m_AssetBundleRequest = null;
 private AsyncOperation m_AsyncOperation = null;

 private EventHandler<LoadResourceAgentHelperUpdateEventArgs> m_LoadResourceAgentHelperUpdateEventHandler = null;
 private EventHandler<LoadResourceAgentHelperReadFileCompleteEventArgs> m_LoadResourceAgentHelperReadFileCompleteEventHandler = null;
 private EventHandler<LoadResourceAgentHelperReadBytesCompleteEventArgs> m_LoadResourceAgentHelperReadBytesCompleteEventHandler = null;
 private EventHandler<LoadResourceAgentHelperParseBytesCompleteEventArgs> m_LoadResourceAgentHelperParseBytesCompleteEventHandler = null;
 private EventHandler<LoadResourceAgentHelperLoadCompleteEventArgs> m_LoadResourceAgentHelperLoadCompleteEventHandler = null;
 private EventHandler<LoadResourceAgentHelperErrorEventArgs> m_LoadResourceAgentHelperErrorEventHandler = null;

 /// <summary>
 /// 加载资源代理辅助器异步加载资源更新事件。
 /// </summary>
 public override event EventHandler<LoadResourceAgentHelperUpdateEventArgs> LoadResourceAgentHelperUpdate
 {
 add
 {
 m_LoadResourceAgentHelperUpdateEventHandler += value;
 }
 remove
 {
 m_LoadResourceAgentHelperUpdateEventHandler -= value;
 }
 }

 /// <summary>
 /// 加载资源代理辅助器异步读取资源文件完成事件。
 /// </summary>
 public override event EventHandler<LoadResourceAgentHelperReadFileCompleteEventArgs> LoadResourceAgentHelperReadFileComplete
 {
 add
 {
 m_LoadResourceAgentHelperReadFileCompleteEventHandler += value;
 }
 remove
 {
 m_LoadResourceAgentHelperReadFileCompleteEventHandler -= value;
 }
 }

 /// <summary>
 /// 加载资源代理辅助器异步读取资源二进制流完成事件。
 /// </summary>
 public override event EventHandler<LoadResourceAgentHelperReadBytesCompleteEventArgs> LoadResourceAgentHelperReadBytesComplete
 {
 add
 {
 m_LoadResourceAgentHelperReadBytesCompleteEventHandler += value;
 }
 remove
 {
 m_LoadResourceAgentHelperReadBytesCompleteEventHandler -= value;
 }
 }

 /// <summary>
 /// 加载资源代理辅助器异步将资源二进制流转换为加载对象完成事件。
 /// </summary>
 public override event EventHandler<LoadResourceAgentHelperParseBytesCompleteEventArgs> LoadResourceAgentHelperParseBytesComplete
 {
 add
 {
 m_LoadResourceAgentHelperParseBytesCompleteEventHandler += value;
 }
 remove
 {
 m_LoadResourceAgentHelperParseBytesCompleteEventHandler -= value;
 }
 }

 /// <summary>
 /// 加载资源代理辅助器异步加载资源完成事件。
 /// </summary>
 public override event EventHandler<LoadResourceAgentHelperLoadCompleteEventArgs> LoadResourceAgentHelperLoadComplete
 {
 add
 {
 m_LoadResourceAgentHelperLoadCompleteEventHandler += value;
 }
 remove
 {
 m_LoadResourceAgentHelperLoadCompleteEventHandler -= value;
 }
 }

 /// <summary>
 /// 加载资源代理辅助器错误事件。
 /// </summary>
 public override event EventHandler<LoadResourceAgentHelperErrorEventArgs> LoadResourceAgentHelperError
 {
 add
 {
 m_LoadResourceAgentHelperErrorEventHandler += value;
 }
 remove
 {
 m_LoadResourceAgentHelperErrorEventHandler -= value;
 }
 }

 /// <summary>
 /// 通过加载资源代理辅助器开始异步读取资源文件。
 /// </summary>
 /// <param name="fullPath">要加载资源的完整路径名。</param>
 public override void ReadFile(string fullPath)
 {
 if (m_LoadResourceAgentHelperReadFileCompleteEventHandler == null || m_LoadResourceAgentHelperUpdateEventHandler == null || m_LoadResourceAgentHelperErrorEventHandler == null)
 {
 Log.Fatal("Load resource agent helper handler is invalid.");
 return;
 }

 m_FileFullPath = fullPath;
 m_FileAssetBundleCreateRequest = AssetBundle.LoadFromFileAsync(m_FileFullPath);
 }

 /// <summary>
 /// 通过加载资源代理辅助器开始异步读取资源二进制流。
 /// </summary>
 /// <param name="fullPath">要加载资源的完整路径名。</param>
 /// <param name="loadType">资源加载方式。</param>
 public override void ReadBytes(string fullPath, int loadType)
 {
 if (m_LoadResourceAgentHelperReadBytesCompleteEventHandler == null || m_LoadResourceAgentHelperUpdateEventHandler == null || m_LoadResourceAgentHelperErrorEventHandler == null)
 {
 Log.Fatal("Load resource agent helper handler is invalid.");
 return;
 }

 m_BytesFullPath = fullPath;
 m_LoadType = loadType;
#if UNITY_5_4_OR_NEWER
 m_UnityWebRequest = UnityWebRequest.Get(Utility.Path.GetRemotePath(fullPath));
#if UNITY_2017_2_OR_NEWER
 m_UnityWebRequest.SendWebRequest();
#else
 m_UnityWebRequest.Send();
#endif
#else
 m_WWW = new WWW(Utility.Path.GetRemotePath(fullPath));
#endif
 }

 /// <summary>
 /// 通过加载资源代理辅助器开始异步将资源二进制流转换为加载对象。
 /// </summary>
 /// <param name="bytes">要加载资源的二进制流。</param>
 public override void ParseBytes(byte[] bytes)
 {
 if (m_LoadResourceAgentHelperParseBytesCompleteEventHandler == null || m_LoadResourceAgentHelperUpdateEventHandler == null || m_LoadResourceAgentHelperErrorEventHandler == null)
 {
 Log.Fatal("Load resource agent helper handler is invalid.");
 return;
 }

 m_BytesAssetBundleCreateRequest = AssetBundle.LoadFromMemoryAsync(bytes);
 }

 /// <summary>
 /// 通过加载资源代理辅助器开始异步加载资源。
 /// </summary>
 /// <param name="resource">资源。</param>
 /// <param name="assetName">要加载的资源名称。</param>
 /// <param name="assetType">要加载资源的类型。</param>
 /// <param name="isScene">要加载的资源是否是场景。</param>
 public override void LoadAsset(object resource, string assetName, Type assetType, bool isScene)
 {
 if (m_LoadResourceAgentHelperLoadCompleteEventHandler == null || m_LoadResourceAgentHelperUpdateEventHandler == null || m_LoadResourceAgentHelperErrorEventHandler == null)
 {
 Log.Fatal("Load resource agent helper handler is invalid.");
 return;
 }

 AssetBundle assetBundle = resource as AssetBundle;
 if (assetBundle == null)
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.TypeError, "Can not load asset bundle from loaded resource which is not an asset bundle."));
 return;
 }

 if (string.IsNullOrEmpty(assetName))
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.AssetError, "Can not load asset from asset bundle which child name is invalid."));
 return;
 }

 m_AssetName = assetName;
 if (isScene)
 {
 int sceneNamePositionStart = assetName.LastIndexOf('/');
 int sceneNamePositionEnd = assetName.LastIndexOf('.');
 if (sceneNamePositionStart <= 0 || sceneNamePositionEnd <= 0 || sceneNamePositionStart > sceneNamePositionEnd)
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.AssetError, Utility.Text.Format("Scene name '{0}' is invalid.", assetName)));
 return;
 }

 string sceneName = assetName.Substring(sceneNamePositionStart + 1, sceneNamePositionEnd - sceneNamePositionStart - 1);
 m_AsyncOperation = SceneManager.LoadSceneAsync(sceneName, LoadSceneMode.Additive);
 }
 else
 {
 if (assetType != null)
 {
 m_AssetBundleRequest = assetBundle.LoadAssetAsync(assetName, assetType);
 }
 else
 {
 m_AssetBundleRequest = assetBundle.LoadAssetAsync(assetName);
 }
 }
 }

 /// <summary>
 /// 重置加载资源代理辅助器。
 /// </summary>
 public override void Reset()
 {
 m_FileFullPath = null;
 m_BytesFullPath = null;
 m_LoadType = 0;
 m_AssetName = null;
 m_LastProgress = 0f;

#if UNITY_5_4_OR_NEWER
 if (m_UnityWebRequest != null)
 {
 m_UnityWebRequest.Dispose();
 m_UnityWebRequest = null;
 }
#else
 if (m_WWW != null)
 {
 m_WWW.Dispose();
 m_WWW = null;
 }
#endif

 m_FileAssetBundleCreateRequest = null;
 m_BytesAssetBundleCreateRequest = null;
 m_AssetBundleRequest = null;
 m_AsyncOperation = null;
 }

 /// <summary>
 /// 释放资源。
 /// </summary>
 public void Dispose()
 {
 Dispose(true);
 GC.SuppressFinalize(this);
 }

 /// <summary>
 /// 释放资源。
 /// </summary>
 /// <param name="disposing">释放资源标记。</param>
 private void Dispose(bool disposing)
 {
 if (m_Disposed)
 {
 return;
 }

 if (disposing)
 {
#if UNITY_5_4_OR_NEWER
 if (m_UnityWebRequest != null)
 {
 m_UnityWebRequest.Dispose();
 m_UnityWebRequest = null;
 }
#else
 if (m_WWW != null)
 {
 m_WWW.Dispose();
 m_WWW = null;
 }
#endif
 }

 m_Disposed = true;
 }

 private void Update()
 {
#if UNITY_5_4_OR_NEWER
 UpdateUnityWebRequest();
#else
 UpdateWWW();
#endif
 UpdateFileAssetBundleCreateRequest();
 UpdateBytesAssetBundleCreateRequest();
 UpdateAssetBundleRequest();
 UpdateAsyncOperation();
 }

#if UNITY_5_4_OR_NEWER
 private void UpdateUnityWebRequest()
 {
 if (m_UnityWebRequest != null)
 {
 if (m_UnityWebRequest.isDone)
 {
 if (string.IsNullOrEmpty(m_UnityWebRequest.error))
 {
 m_LoadResourceAgentHelperReadBytesCompleteEventHandler(this, new LoadResourceAgentHelperReadBytesCompleteEventArgs(m_UnityWebRequest.downloadHandler.data, m_LoadType));
 m_UnityWebRequest.Dispose();
 m_UnityWebRequest = null;
 m_BytesFullPath = null;
 m_LoadType = 0;
 m_LastProgress = 0f;
 }
 else
 {
 bool isError = false;
#if UNITY_2017_1_OR_NEWER
 isError = m_UnityWebRequest.isNetworkError;
#else
 isError = m_UnityWebRequest.isError;
#endif
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.NotExist, Utility.Text.Format("Can not load asset bundle '{0}' with error message '{1}'.", m_BytesFullPath, isError ? m_UnityWebRequest.error : null)));
 }
 }
 else if (m_UnityWebRequest.downloadProgress != m_LastProgress)
 {
 m_LastProgress = m_UnityWebRequest.downloadProgress;
 m_LoadResourceAgentHelperUpdateEventHandler(this, new LoadResourceAgentHelperUpdateEventArgs(LoadResourceProgress.ReadResource, m_UnityWebRequest.downloadProgress));
 }
 }
 }
#else
 private void UpdateWWW()
 {
 if (m_WWW != null)
 {
 if (m_WWW.isDone)
 {
 if (string.IsNullOrEmpty(m_WWW.error))
 {
 m_LoadResourceAgentHelperReadBytesCompleteEventHandler(this, new LoadResourceAgentHelperReadBytesCompleteEventArgs(m_WWW.bytes, m_LoadType));
 m_WWW.Dispose();
 m_WWW = null;
 m_BytesFullPath = null;
 m_LoadType = 0;
 m_LastProgress = 0f;
 }
 else
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.NotExist, Utility.Text.Format("Can not load asset bundle '{0}' with error message '{1}'.", m_BytesFullPath, m_WWW.error)));
 }
 }
 else if (m_WWW.progress != m_LastProgress)
 {
 m_LastProgress = m_WWW.progress;
 m_LoadResourceAgentHelperUpdateEventHandler(this, new LoadResourceAgentHelperUpdateEventArgs(LoadResourceProgress.ReadResource, m_WWW.progress));
 }
 }
 }
#endif

 private void UpdateFileAssetBundleCreateRequest()
 {
 if (m_FileAssetBundleCreateRequest != null)
 {
 if (m_FileAssetBundleCreateRequest.isDone)
 {
 AssetBundle assetBundle = m_FileAssetBundleCreateRequest.assetBundle;
 if (assetBundle != null)
 {
 AssetBundleCreateRequest oldFileAssetBundleCreateRequest = m_FileAssetBundleCreateRequest;
 m_LoadResourceAgentHelperReadFileCompleteEventHandler(this, new LoadResourceAgentHelperReadFileCompleteEventArgs(assetBundle));
 if (m_FileAssetBundleCreateRequest == oldFileAssetBundleCreateRequest)
 {
 m_FileAssetBundleCreateRequest = null;
 m_LastProgress = 0f;
 }
 }
 else
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.NotExist, Utility.Text.Format("Can not load asset bundle from file '{0}' which is not a valid asset bundle.", m_FileFullPath)));
 }
 }
 else if (m_FileAssetBundleCreateRequest.progress != m_LastProgress)
 {
 m_LastProgress = m_FileAssetBundleCreateRequest.progress;
 m_LoadResourceAgentHelperUpdateEventHandler(this, new LoadResourceAgentHelperUpdateEventArgs(LoadResourceProgress.LoadResource, m_FileAssetBundleCreateRequest.progress));
 }
 }
 }

 private void UpdateBytesAssetBundleCreateRequest()
 {
 if (m_BytesAssetBundleCreateRequest != null)
 {
 if (m_BytesAssetBundleCreateRequest.isDone)
 {
 AssetBundle assetBundle = m_BytesAssetBundleCreateRequest.assetBundle;
 if (assetBundle != null)
 {
 AssetBundleCreateRequest oldBytesAssetBundleCreateRequest = m_BytesAssetBundleCreateRequest;
 m_LoadResourceAgentHelperParseBytesCompleteEventHandler(this, new LoadResourceAgentHelperParseBytesCompleteEventArgs(assetBundle));
 if (m_BytesAssetBundleCreateRequest == oldBytesAssetBundleCreateRequest)
 {
 m_BytesAssetBundleCreateRequest = null;
 m_LastProgress = 0f;
 }
 }
 else
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.NotExist, "Can not load asset bundle from memory which is not a valid asset bundle."));
 }
 }
 else if (m_BytesAssetBundleCreateRequest.progress != m_LastProgress)
 {
 m_LastProgress = m_BytesAssetBundleCreateRequest.progress;
 m_LoadResourceAgentHelperUpdateEventHandler(this, new LoadResourceAgentHelperUpdateEventArgs(LoadResourceProgress.LoadResource, m_BytesAssetBundleCreateRequest.progress));
 }
 }
 }

 private void UpdateAssetBundleRequest()
 {
 if (m_AssetBundleRequest != null)
 {
 if (m_AssetBundleRequest.isDone)
 {
 if (m_AssetBundleRequest.asset != null)
 {
 m_LoadResourceAgentHelperLoadCompleteEventHandler(this, new LoadResourceAgentHelperLoadCompleteEventArgs(m_AssetBundleRequest.asset));
 m_AssetName = null;
 m_LastProgress = 0f;
 m_AssetBundleRequest = null;
 }
 else
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.AssetError, Utility.Text.Format("Can not load asset '{0}' from asset bundle which is not exist.", m_AssetName)));
 }
 }
 else if (m_AssetBundleRequest.progress != m_LastProgress)
 {
 m_LastProgress = m_AssetBundleRequest.progress;
 m_LoadResourceAgentHelperUpdateEventHandler(this, new LoadResourceAgentHelperUpdateEventArgs(LoadResourceProgress.LoadAsset, m_AssetBundleRequest.progress));
 }
 }
 }

 private void UpdateAsyncOperation()
 {
 if (m_AsyncOperation != null)
 {
 if (m_AsyncOperation.isDone)
 {
 if (m_AsyncOperation.allowSceneActivation)
 {
 m_LoadResourceAgentHelperLoadCompleteEventHandler(this, new LoadResourceAgentHelperLoadCompleteEventArgs(new SceneAsset()));
 m_AssetName = null;
 m_LastProgress = 0f;
 m_AsyncOperation = null;
 }
 else
 {
 m_LoadResourceAgentHelperErrorEventHandler(this, new LoadResourceAgentHelperErrorEventArgs(LoadResourceStatus.AssetError, Utility.Text.Format("Can not load scene asset '{0}' from asset bundle.", m_AssetName)));
 }
 }
 else if (m_AsyncOperation.progress != m_LastProgress)
 {
 m_LastProgress = m_AsyncOperation.progress;
 m_LoadResourceAgentHelperUpdateEventHandler(this, new LoadResourceAgentHelperUpdateEventArgs(LoadResourceProgress.LoadScene, m_AsyncOperation.progress));
 }
 }
 }
 }
}