//-----------------------------------------------------------------------
// <copyright file="Response.cs" company="Andrew Arnott">
//     Copyright (c) Andrew Arnott. All rights reserved.
// </copyright>
//-----------------------------------------------------------------------

namespace DotNetOAuth.Messaging {
	using System;
	using System.Net;
	using System.Web;

	/// <summary>
	/// A protocol message (request or response) that passes between Consumer and Service Provider
	/// via the user agent using a redirect or form POST submission,
	/// OR a direct message response.
	/// </summary>
	/// <remarks>
	/// <para>An instance of this type describes the HTTP response that must be sent
	/// in response to the current HTTP request.</para>
	/// <para>It is important that this response make up the entire HTTP response.
	/// A hosting ASPX page should not be allowed to render its normal HTML output
	/// after this response is sent.  The normal rendered output of an ASPX page 
	/// can be canceled by calling <see cref="HttpResponse.End"/> after this message
	/// is sent on the response stream.</para>
	/// </remarks>
	public class Response {
		/// <summary>
		/// Gets the headers that must be included in the response to the user agent.
		/// </summary>
		/// <remarks>
		/// The headers in this collection are not meant to be a comprehensive list
		/// of exactly what should be sent, but are meant to augment whatever headers
		/// are generally included in a typical response.
		/// </remarks>
		public WebHeaderCollection Headers { get; internal set; }

		/// <summary>
		/// Gets the body of the HTTP response.
		/// </summary>
		public byte[] Body { get; internal set; }

		/// <summary>
		/// Gets the HTTP status code to use in the HTTP response.
		/// </summary>
		public HttpStatusCode Status { get; internal set; }

		/// <summary>
		/// Gets or sets a reference to the actual protocol message that
		/// is being sent via the user agent.
		/// </summary>
		internal IProtocolMessage OriginalMessage { get; set; }

		/// <summary>
		/// Automatically sends the appropriate response to the user agent.
		/// Requires a current HttpContext.
		/// </summary>
		public void Send() {
			if (HttpContext.Current == null) {
				throw new InvalidOperationException(Strings.CurrentHttpContextRequired);
			}

			HttpContext.Current.Response.Clear();
			HttpContext.Current.Response.StatusCode = (int)this.Status;
			MessagingUtilities.ApplyHeadersToResponse(this.Headers, HttpContext.Current.Response);
			if (this.Body != null && this.Body.Length > 0) {
				HttpContext.Current.Response.OutputStream.Write(this.Body, 0, this.Body.Length);
				HttpContext.Current.Response.OutputStream.Flush();
			}
			HttpContext.Current.Response.OutputStream.Close();
			HttpContext.Current.Response.End();
		}
	}
}