#region License

/*
* SunriseUpload - Asp.net Upload Component
*
* Copyright (C) 2004 mic <mic4free@hotmail.com>
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*
* In case your copy of SunriseUpload does not include a copy of the license, you may find it online at 
* http://www.gnu.org/copyleft/gpl.html
*
* You can find new release of this component at http://athena.9966.org/SunriseUpload .
*/

#endregion

using System;
using System.Collections;
using System.IO;
using System.Reflection;
using System.Text;
using System.Web;
using System.Xml;

namespace WUSGControl.Web.Upload
{
	/// <summary>
	/// The core of SunriseUpload.
	/// </summary>
	public class HttpUploadModule : IHttpModule
	{
		private DateTime beginTime = DateTime.Now;

		private HttpUploadModule()
		{
		}

		/// <summary>
		/// Get value from preloaded entity body. Identified by name.
		/// 解析preloadedContent中的字符 0fdde0fc-d9fb-4fb1-b45c-badac1f94a7c, 這個是在注冊按鈕時向業(yè)面注冊的一個隱藏字段
		/// </summary>
		/// <param name="preloadedEntityBody"></param>
		/// <param name="name"></param>
		/// <returns></returns>
		private string AnalysePreloadedEntityBody(byte[] preloadedEntityBody, string name)
		{
			string val = string.Empty;
			
			string preloadedContent = Utils.GetContext().Request.ContentEncoding.GetString(preloadedEntityBody);
			//Utils.GetContext().Response.Write(preloadedContent);
			//字符源樣不能被打印出來,在這里寫入文件有錯.
			//Utils.2writem("preloadedContent正文已被讀取的為: " + preloadedContent);
			if (preloadedContent.Length > 0)
			{
				int startIndex = ((preloadedContent.IndexOf(("name=\"" + name + "\"")) + 11) + name.Length);
				//Utils.2writem("計算位置"+("name=\"" + name + "\""));
				int endIndex = preloadedContent.IndexOf("\r\n", startIndex);
				val = preloadedContent.Substring(startIndex, (endIndex - startIndex));
			}
			//Utils.2writem("解析val為:" + val);
			return val;
		}

		/// <summary>
		/// Event handler of request
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private void Application_BeginRequest(object sender, EventArgs e)
		{
			//Utils.writem("應用程序請求開始!");

			HttpApplication application = (sender as HttpApplication);
			HttpWorkerRequest workerRequest = GetWorkerRequest();

			try
			{
				//Handle upload request only.
				if (!IsUploadRequest(application.Request))
				{
					//Utils.2writem("httpModule第一次返回!");
					return;
				}
				//一般第一條可以檢測過,但這一條如果不是在上傳則不可以通過
				//只處理 包含 body 數(shù)據(jù) 的request
				if (!workerRequest.HasEntityBody())
				{
					//Utils.2writem("httpModule第二次返回!");
					return;
				}
				//Utils.2writem("Http的版本為: " + workerRequest.GetHttpVersion());
				//Define a local value to store the current position of total bytes.
				int currentPosition = 0;

				TimeSpan span = DateTime.Now.Subtract(this.beginTime);
				string contentType = application.Context.Request.ContentType.ToLower();
				
				//Utils.2writem("contentType為"+ application.Context.Request.ContentType + "! application.Context.Request.ContentLength長度為"+application.Context.Request.ContentLength + "! 編碼為:" + application.Context.Request.ContentEncoding.ToString());
				//Utils.2writem("處理過的contentType為 :" +"\r\n--" + contentType.Substring((contentType.IndexOf("boundary=") + 9)));
				string b = ("\r\n--" + contentType.Substring((contentType.IndexOf("boundary=") + 9)));
				byte[] boundaryData = Encoding.ASCII.GetBytes(b.ToCharArray());//數(shù)據(jù)劃分邊界
				//返回與指定索引相對應的標準的http請求頭, 請求數(shù)據(jù)的長度
				int FileLength = Convert.ToInt32(workerRequest.GetKnownRequestHeader(11));
				
				//Utils.2writem("FileLength的長度為,此長度代表請求的長度,不是文件實際的長度" + FileLength.ToString());
				
				UploadStatus uploadStatus = new UploadStatus();
				application.Context.Items.Add("Sunrise_Web_Upload_FileList", new Hashtable());

				//返回http請求正文已被讀取的部分, 就是桌面上的一個文本文件，
				byte[] preloadedEntityBody = workerRequest.GetPreloadedEntityBody();
                if (preloadedEntityBody == null)
                    return;
				string a = Encoding.ASCII.GetString(preloadedEntityBody);
				//Utils.2writem("返回http請求正文已被讀取的部分為" + a);
				//已被讀取的位置要加上已讀數(shù)據(jù)實體的位置
				currentPosition += preloadedEntityBody.Length;
				//獲得維一ID c92b90af-f0ea-4a7c-824d-50ccde32f638
				string uploadGuid = this.AnalysePreloadedEntityBody(preloadedEntityBody, "Sunrise_Web_Upload_UploadGUID");

				if (uploadGuid != string.Empty)
				{
					application.Context.Items.Add("Sunrise_Web_Upload_UploadGUID", uploadGuid);//保存后如何訪問呢
				}

				bool isUploadFinished = true;
				if ((FileLength > this.GetUpLoadFileLength())//文件的長度大于最大的長度
					&& ((0 > span.TotalHours) || (span.TotalHours > 3)))
				{
					isUploadFinished = false;//上傳未結束
				}
				if ((0 > span.TotalHours) || (span.TotalHours > 3))
				{
					isUploadFinished = false;
				}

				string uploadFolder = this.AnalysePreloadedEntityBody(preloadedEntityBody, "Sunrise_Web_Upload_UploadFolder");
				//Utils.2writem("上傳文件夾為: " + uploadFolder.ToString());
				if (uploadFolder.IndexOf(@":\") < 0)
				{
					uploadFolder = Path.GetTempPath();//先上傳到臨時路徑中,這個可以自已定義
				}

				ArrayList readBody = new ArrayList();
				//Utils.2writem("preloadedEntityBody  is " + preloadedEntityBody.ToString() + "|boundaryData is" + boundaryData.ToString() + "uploadFolder is" + uploadFolder);
				RequestStream preloadedStream = new RequestStream(preloadedEntityBody, boundaryData,
				                                                  null, RequestStream.FileStatus.Close, RequestStream.ReadStatus.NoRead, uploadFolder, isUploadFinished, application.Context, string.Empty);

				readBody.AddRange(preloadedStream.ReadBody);
//**********************************************************************************************************
				//Set upload status. 更新上傳狀態(tài)
				if (uploadGuid != string.Empty)
				{
					uploadStatus.FileLength = FileLength; //是兩個文件的總長度,還是一個文件的長度呢.
					uploadStatus.ReceivedLength = currentPosition;
					uploadStatus.FileName = preloadedStream.OriginalFileName;
					uploadStatus.FileCount = ((Hashtable) application.Context.Items["Sunrise_Web_Upload_FileList"]).Count;
                    //if (uploadStatus.FileCount == 2)
                    //{
                    //    string c = "b";//跟蹤,測試.
                    //}

					application.Application[("_UploadGUID_" + uploadGuid)] = uploadStatus;
				}
				//Utils.2writem("準備進入workerRequest.IsEntireEntityBodyIsPreloaded");
				//Is all data have been preload? //判斷是否還有數(shù)據(jù)可讀
                //if (workerRequest.IsEntireEntityBodyIsPreloaded())//這個方法很不穩(wěn)定,有時可以有時不行，所以去掉，這樣就比較好
                //{
					//Utils.2writem("進入workerRequest.IsEntireEntityBodyIsPreloaded一次");

					byte[] boudaryContent;
					ArrayList contentBody;

					//Define size of boundary.
                    int boundarySize = 655350;
					byte[] boudaryBuffer = new byte[boundarySize];
					//讀取已分好的數(shù)據(jù)塊,
					//Read each data block into read body array. 
					while (((FileLength - currentPosition) >= boundarySize))
					{
						//If client is disconnected, clear all resources in use.//客戶端失去聯(lián)接時則釋放應用程序資源
						if (!application.Context.Response.IsClientConnected)//客戶端超時
						{
							this.ReleaseRes(application);
							//throw exception;
						}

						//Read bytes from request. 讀取客戶端請求數(shù)據(jù), 讀取數(shù)據(jù)到緩存中,返回已讀取的字節(jié)數(shù)
						//讀取一個字節(jié)流
						boundarySize = workerRequest.ReadEntityBody(boudaryBuffer, boudaryBuffer.Length);
						currentPosition += boundarySize;//再讀取一個緩沖大小的數(shù)據(jù),所以讀取位置要往前加1
						//contentBody中保存些什么東西呢
						contentBody = preloadedStream.ContentBody;
						////Utils.2writem("("preloadedStream.ContentBody 是"+preloadedStream.ContentBody);
						if (contentBody.Count > 0)//如果已讀取了一部分則
						{
							////Utils.2writem("("第二次進入流!");

							boudaryContent = new byte[(contentBody.Count + boudaryBuffer.Length)];
							contentBody.CopyTo(boudaryContent, 0);//把內(nèi)容拷貝到boudaryContent中保存
							////Utils.2writem("("boudaryContent 長度是" + boudaryContent.Length);
							boudaryBuffer.CopyTo(boudaryContent, contentBody.Count);//boudaryContent

							//加到文件流里面
							preloadedStream = new RequestStream(boudaryContent, boundaryData,
							                                    preloadedStream.FileStream, preloadedStream.FStatus, preloadedStream.RStatus, uploadFolder, isUploadFinished, application.Context, preloadedStream.OriginalFileName);
						}
						else
						{
							////Utils.2writem("("第一次進入流");
							//第一次讀取
							preloadedStream = new RequestStream(boudaryBuffer, boundaryData,
							                                    preloadedStream.FileStream, preloadedStream.FStatus, preloadedStream.RStatus, uploadFolder, isUploadFinished, application.Context, preloadedStream.OriginalFileName);
						}

						//Append data block to read body array
						readBody.AddRange(preloadedStream.ReadBody);

						//Set upload status.
						if (uploadGuid != string.Empty)
						{
							uploadStatus.ReceivedLength = currentPosition;
							uploadStatus.FileName = preloadedStream.OriginalFileName;
							uploadStatus.FileCount = ((Hashtable) application.Context.Items["Sunrise_Web_Upload_FileList"]).Count;
							application.Application[("_UploadGUID_" + uploadGuid)] = uploadStatus;
						}
					}
//**********************************************************************************************************
					//The rest request data //所有數(shù)據(jù)已處理完畢，查看其它數(shù)據(jù)，最后一點數(shù)據(jù)單獨解析