//
// System.Web.StaticFileHandler
//
// Authors:
//	Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// (C) 2002 Ximian, Inc (http://www.ximian.com)
//

//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Globalization;
using System.IO;

namespace System.Web
{
	class StaticFileHandler : IHttpHandler
	{
		public void ProcessRequest (HttpContext context)
		{
			HttpRequest request = context.Request;
			HttpResponse response = context.Response;
			string fileName = request.PhysicalPath;
			FileInfo fi = new FileInfo (fileName);
			if (!fi.Exists)
				throw new HttpException (404, "File '" + request.FilePath + "' not found.");

			if ((fi.Attributes & FileAttributes.Directory) != 0) {
				response.Redirect (request.Path + '/');
				return;
			}

			string strHeader = request.Headers ["If-Modified-Since"];
			try {
				if (strHeader != null) {
					DateTime dtIfModifiedSince = DateTime.ParseExact (strHeader, "r", null);
					DateTime ftime;
#if TARGET_JVM
					try 
					{
						ftime = fi.LastWriteTime.ToUniversalTime ();
					} 
					catch (NotSupportedException) 
					{
						// The file is in a WAR, it might be modified with last redeploy.
						try {
							ftime = (DateTime) AppDomain.CurrentDomain.GetData (".appStartTime");
						}
						catch {
							ftime = DateTime.MaxValue;
						}
					}
#else
					ftime = fi.LastWriteTime.ToUniversalTime ();
#endif
					if (ftime <= dtIfModifiedSince) {
						response.StatusCode = 304;
						return;
					}
				}
			} catch { } 

			try {
				DateTime lastWT = fi.LastWriteTime.ToUniversalTime ();
				response.AddHeader ("Last-Modified", lastWT.ToString ("r"));

				response.ContentType = MimeTypes.GetMimeType (fileName);
				response.TransmitFile (fileName, true);
			} catch (Exception) {
				throw new HttpException (403, "Forbidden.");
			}
		}

		public bool IsReusable {
			get { return true; }
		}
	}
}