using System;
using System.Net;
using System.Web;
using System.IO;
using System.Collections;
using System.Collections.Specialized;
using System.Collections.Generic;
using System.Text;

namespace Rocky.Net
{
public class HttpWalker
    {
#region StaticMembers
public static void DownloadFile(HttpContext context, string filePath)
        {
            AppRuntime.Guard<ArgumentNullException>(context == null);
            HttpRequest Request = context.Request;
            HttpResponse Response = context.Response;
            Response.Clear();
            Response.Buffer = false;
            Response.AddHeader("Accept-Ranges", "bytes");
using (FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
            {
byte[] buffer = BufferUtility.GetBuffer((int)stream.Length);
long p = 0L, l = stream.Length;
#region Resolve Range
string range = Request.Headers["Range"];
if (range != null)
                {
//Range:bytes=1024-
//Range:bytes=1024-2048
//Range:bytes=-1024
//Range:bytes=0-512,1024-2048
                    int index = range.IndexOf("=");
if (index != -1)
                    {
string[] ranges = range.Substring(index + 1).Split(',');
if (ranges.Length > 1)
                        {
//not supported multipart/byterange
                        }
else
                        {
bool flag = false;
if (ranges[0].StartsWith("-"))
                            {
long _p, _absp;
if (long.TryParse(ranges[0], out _p) && (_absp = Math.Abs(_p)) <= l)
                                {
if (_p < 0)
                                    {
                                        p = l - _absp;
                                        l = _absp;
                                        flag = true;
                                    }
                                }
                            }
else
                            {
                                ranges = ranges[0].Split('-');
if (ranges.Length == 2)
                                {
long _p, _l;
if (ranges[1] == string.Empty)
                                    {
if (long.TryParse(ranges[0], out _p) && _p <= l)
                                        {
                                            p = _p;
                                            flag = true;
                                        }
                                    }
else if (long.TryParse(ranges[0], out _p) && long.TryParse(ranges[1], out _l) && _p > 0 && _l > 0 && _p < _l && _l < l)
                                    {
                                        p = _p;
                                        l = _l + 1;
                                        flag = true;
                                    }
                                }
                            }
if (flag)
                            {
                                Response.StatusCode = 206;
                                Response.AddHeader("Content-Range", "bytes " + p.ToString() + "-" + l.ToString() + "/" + stream.Length.ToString());
                            }
else
                            {
                                Response.StatusCode = 416;  //Requested range not satisfiable
                            }
                        }
                    }
                }
#endregion
                Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(Path.GetFileName(filePath), Encoding.UTF8));
                Response.AddHeader("Content-Length", l.ToString());
                Response.ContentType = "application/octet-stream";
                stream.Position = p;
int read;
while (Response.IsClientConnected && p < l)
                {
                    Response.OutputStream.Write(buffer, 0, read = stream.Read(buffer, 0, buffer.Length));
                    Response.Flush();
                    p += read;
                }
            }
            Response.End();
        }

public static void UploadFile(HttpContext context, string savePath)
        {
            AppRuntime.Guard<ArgumentNullException>(context == null);
            HttpRequest Request = context.Request;
            HttpResponse Response = context.Response;
string msg = "0", fileName = Request.Headers["filename"];
if (fileName != null)
            {
                FileInfo file = new FileInfo(Path.Combine(Path.GetDirectoryName(savePath), fileName));
if (Request.Headers["breakpoint"] == bool.TrueString)
                {
                    Response.AddHeader("Content-Length", (file.Exists ? file.Length : 0L).ToString());
                }
else
                {
long l;
if (Request.Files.Count > 0 && long.TryParse(Request.Headers["breakpoint"], out l))
                    {
                        HttpPostedFile postedFile = Request.Files[0];
using (FileStream stream = file.Open(file.Exists ? FileMode.Append : FileMode.Create, FileAccess.Write, FileShare.None))
                        {
byte[] buffer = BufferUtility.GetBuffer((int)stream.Length);
                            Stream postedStream = postedFile.InputStream;
long p = stream.Position;
int read;
while (Response.IsClientConnected && p < l)
                            {
                                stream.Write(buffer, 0, read = postedStream.Read(buffer, 0, buffer.Length));
                                stream.Flush();
                                p += read;
                            }
                        }
                        file.MoveTo(savePath);
                        msg = "1";
                    }
                }
            }
            Response.Write(msg);
            Response.End();
        }
#endregion

#region Fields
private HttpWebRequest httpRequest;
private CookieContainer cookieContainer;
private string referer;
private NameValueCollection form;
private List<HttpFile> files;
#endregion

#region Properties
public Uri RequestUri
        {
set { httpRequest = (HttpWebRequest)WebRequest.Create(value); }
get { return httpRequest.RequestUri; }
        }
public HttpWebRequest Request
        {
get { return httpRequest; }
        }
public CookieCollection Cookies
        {
get { return cookieContainer.GetCookies(httpRequest.RequestUri); }
        }
public NameValueCollection Form
        {
get
            {
if (form == null)
                {
                    form = new NameValueCollection();
                }
return form;
            }
        }
public List<HttpFile> Files
        {
get
            {
if (files == null)
                {
                    files = new List<HttpFile>();
                }
return files;
            }
        }
#endregion

#region Constructor
public HttpWalker(Uri uri)
        {
this.RequestUri = uri;
            cookieContainer = new CookieContainer();
            referer = "http://www.google.com";
        }
#endregion

#region Methods
public long GetContentLengthByHead()
        {
return GetContentLengthByHead(true);
        }
public long GetContentLengthByHead(bool reset)
        {
using (HttpWebResponse httpResponse = GetResponse(WebRequestMethods.Http.Head))
            {
if (reset)
                {
                    httpRequest = (HttpWebRequest)WebRequest.Create(httpRequest.RequestUri);
                }
return httpResponse.ContentLength;
            }
        }

public HttpWebResponse GetResponse()
        {
if ((form != null && form.Count > 0) || (files != null && files.Count > 0))
            {
return GetResponse(WebRequestMethods.Http.Post);
            }
else
            {
return GetResponse(WebRequestMethods.Http.Get);
            }
        }
public HttpWebResponse GetResponse(string method)
        {
if (httpRequest.RequestUri.Scheme == "https")
            {
                ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback(CheckValidationResult);
            }
            httpRequest.CookieContainer = cookieContainer;
            httpRequest.Referer = referer;
            httpRequest.Accept = "*/*";
            httpRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";
if ((httpRequest.Method = method) == WebRequestMethods.Http.Post)
            {
                StringBuilder sb = new StringBuilder();
if (files.Count > 0)
                {
                    Queue methodQueue = new Queue();
string boundary = Guid.NewGuid().ToString().Replace("-", string.Empty), line = "\r\n";
byte[] beginBoundary = Encoding.ASCII.GetBytes("--" + boundary + line);
//byte[] endBoundary = Encoding.ASCII.GetBytes("--" + boundary + "--" + newLine);
                    httpRequest.ContentType = "multipart/form-data; boundary=" + boundary;
long contentLength = 0L;
if (form != null && form.Count > 0)
                    {
for (int i = 0; i < form.Count; i++)
                        {
                            sb.Length = 0;
                            sb.AppendFormat("Content-Disposition: form-data; name=\"{0}\"\r\n\r\n", form.GetKey(i));
                            sb.AppendFormat("{0}\r\n", form.Get(i));
byte[] header = Encoding.UTF8.GetBytes(sb.ToString());
                            contentLength += beginBoundary.LongLength + header.LongLength;
                            methodQueue.Enqueue(new Action<Stream>(stream =>
                            {
                                stream.Write(beginBoundary, 0, beginBoundary.Length);
                                stream.Write(header, 0, header.Length);
                            }));
                        }
                    }
if (files != null)
                    {
                        sb.Length = 0;
                        sb.Append(line);
                        sb.Append("--" + boundary + line);
byte[] endOfFile = Encoding.ASCII.GetBytes(sb.ToString());
                        files.ForEach(file =>
                        {
                            sb.Length = 0;
                            sb.AppendFormat("Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\n", file.FieldName, Path.GetFileName(file.FileName));
                            sb.Append("Content-Type: application/octet-stream\r\n\r\n");
byte[] header = Encoding.UTF8.GetBytes(sb.ToString());
                            contentLength += beginBoundary.LongLength + header.LongLength + file.ContentLength + endOfFile.LongLength;
                            methodQueue.Enqueue(new Action<Stream>(stream =>
                            {
                                stream.Write(beginBoundary, 0, beginBoundary.Length);
                                stream.Write(header, 0, header.Length);
                                file.WriteTo(stream);
                                stream.Write(endOfFile, 0, endOfFile.Length);
                            }));
                        });
                    }
                    httpRequest.ContentLength = contentLength;
                    Stream requestStream = httpRequest.GetRequestStream();
while (methodQueue.Count > 0)
                    {
                        ((Action<Stream>)methodQueue.Dequeue())(requestStream);
                    }
                    requestStream.Close();
                }
else
                {
if (form != null && form.Count > 0)
                    {
                        httpRequest.ContentType = "application/x-www-form-urlencoded";
                        sb.Append(form.GetKey(0)).Append("=").Append(form.Get(0));
for (int i = 1; i < form.Count; i++)
                        {
                            sb.Append("&").Append(form.GetKey(i)).Append("=").Append(form.Get(i));
                        }
byte[] data = Encoding.UTF8.GetBytes(sb.ToString());
                        httpRequest.ContentLength = data.LongLength;
                        Stream requestStream = httpRequest.GetRequestStream();
                        requestStream.Write(data, 0, data.Length);
                        requestStream.Close();
                    }
                }
            }
            HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.GetResponse();
            referer = httpResponse.ResponseUri.AbsoluteUri;
return httpResponse;
        }
//https
        private bool CheckValidationResult(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certificate, System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors errors)
        {
// Always accept
            return true;
        }

public void Reset(Uri uri)
        {
this.RequestUri = uri;
            cookieContainer = new CookieContainer();
            referer = "http://www.google.com";
if (form != null)
            {
                form.Clear();
            }
if (files != null)
            {
                files.Clear();
            }
        }
public void RefreshCookies()
        {
            cookieContainer = new CookieContainer();
        }

public override string ToString()
        {
            HttpWebResponse httpResponse = GetResponse();
using (StreamReader reader = new StreamReader(httpResponse.GetResponseStream(), Encoding.GetEncoding(httpResponse.CharacterSet ?? "gb2312")))
            {
return reader.ReadToEnd();
            }
        }
#endregion

#region File
public void DownloadFile(string savePath)
        {
using (FileStream stream = new FileStream(savePath, File.Exists(savePath) ? FileMode.Append : FileMode.CreateNew, FileAccess.Write, FileShare.None))
            {
                httpRequest.AddRange((int)stream.Length);
                HttpWebResponse response = GetResponse();
byte[] buffer = new byte[BufferUtility.FileBufferSize];
                Stream responseStream = response.GetResponseStream();
long p = stream.Length, l = response.ContentLength;