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using System;
using System.Linq;
using System.Net;
using MediaBrowser.Net.Handlers;
namespace MediaBrowser.Net
{
public class RequestContext
{
public HttpListenerRequest Request { get; private set; }
public HttpListenerResponse Response { get; private set; }
public string LocalPath
{
get
{
return Request.Url.LocalPath;
}
}
public RequestContext(HttpListenerContext context)
{
Response = context.Response;
Request = context.Request;
}
public void Respond(BaseHandler handler)
{
Response.AddHeader("Access-Control-Allow-Origin", "*");
Response.KeepAlive = true;
foreach (var header in handler.Headers)
{
Response.AddHeader(header.Key, header.Value);
}
int statusCode = handler.StatusCode;
Response.ContentType = handler.ContentType;
TimeSpan cacheDuration = handler.CacheDuration;
if (Request.Headers.AllKeys.Contains("If-Modified-Since"))
{
DateTime ifModifiedSince;
if (DateTime.TryParse(Request.Headers["If-Modified-Since"].Replace(" GMT", string.Empty), out ifModifiedSince))
{
// If the cache hasn't expired yet just return a 304
if (IsCacheValid(ifModifiedSince, cacheDuration, handler.LastDateModified))
{
statusCode = 304;
}
}
}
Response.SendChunked = true;
Response.StatusCode = statusCode;
if (statusCode != 304)
{
if (handler.GzipResponse)
{
Response.AddHeader("Content-Encoding", "gzip");
}
if (cacheDuration.Ticks > 0)
{
CacheResponse(Response, cacheDuration, handler.LastDateModified);
}
handler.WriteStream(Response.OutputStream);
}
else
{
Response.OutputStream.Flush();
Response.OutputStream.Close();
}
}
private void CacheResponse(HttpListenerResponse response, TimeSpan duration, DateTime? dateModified)
{
DateTime lastModified = dateModified ?? DateTime.Now;
response.Headers[HttpResponseHeader.CacheControl] = "Public";
response.Headers[HttpResponseHeader.Expires] = DateTime.Now.Add(duration).ToString("r");
response.Headers[HttpResponseHeader.LastModified] = lastModified.ToString("r");
}
private bool IsCacheValid(DateTime ifModifiedSince, TimeSpan cacheDuration, DateTime? dateModified)
{
if (dateModified.HasValue)
{
DateTime lastModified = NormalizeDateForComparison(dateModified.Value);
ifModifiedSince = NormalizeDateForComparison(ifModifiedSince);
return lastModified <= ifModifiedSince;
}
DateTime cacheExpirationDate = ifModifiedSince.Add(cacheDuration);
if (DateTime.Now < cacheExpirationDate)
{
return true;
}
return false;
}
/// <summary>
/// When the browser sends the IfModifiedDate, it's precision is limited to seconds, so this will account for that
/// </summary>
private DateTime NormalizeDateForComparison(DateTime date)
{
return new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second);
}
}
}
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