using System;
using System.Collections.Generic;
using System.Net;
using System.Threading;
using JsonObject = System.Collections.Generic.Dictionary<string, object>;

namespace Launcher2 {
	
	public class Build {
		public DateTime TimeBuilt;
		public string DirectXPath, OpenGLPath;
		public int DirectXSize, OpenGLSize;
	}
	
	public sealed class UpdateCheckTask : IWebTask {
		
		public const string UpdatesUri = "http://cs.classicube.net/";
		public const string BuildsUri = "http://cs.classicube.net/builds.json";	
		public Build LatestDev, LatestStable;
		
		public void CheckForUpdatesAsync() {
			Working = true;
			Exception = null;
			LatestDev = null;
			LatestStable = null;
			
			Thread thread = new Thread( UpdateWorker, 256 * 1024 );
			thread.Name = "Launcher.UpdateCheck";
			thread.Start();
		}
		
		void UpdateWorker() {
			try {
				CheckUpdates();
			} catch( WebException ex ) {
				Finish( false, ex, null ); return;
			}
			Finish( true, null, null );
		}
		
		void CheckUpdates() {
			string response = GetHtmlAll( BuildsUri, UpdatesUri );
			int index = 0; bool success = true;
			JsonObject data = (JsonObject)Json.ParseValue( response, ref index, ref success );
			
			JsonObject devBuild = (JsonObject)data["latest"];
			JsonObject releaseBuilds = (JsonObject)data["releases"];		
			LatestDev = MakeBuild( devBuild, false );		
			Build[] stableBuilds = new Build[releaseBuilds.Count];
			
			int i = 0;
			foreach( KeyValuePair<string, object> pair in releaseBuilds )
				stableBuilds[i++] = MakeBuild( (JsonObject)pair.Value, true );		
			Array.Sort<Build>( stableBuilds, 
			                  (a, b) => b.TimeBuilt.CompareTo( a.TimeBuilt ) );
			LatestStable = stableBuilds[0];
		}
		
		static readonly DateTime epoch = new DateTime( 1970, 1, 1, 0, 0, 0, DateTimeKind.Utc );
		Build MakeBuild( JsonObject obj, bool release ) {
			Build build = new Build();
			string timeKey = release ? "release_ts" : "ts";
			double rawTime = Double.Parse( (string)obj[timeKey] );
			build.TimeBuilt = epoch.AddSeconds( rawTime ).ToLocalTime();
			
			build.DirectXSize = Int32.Parse( (string)obj["dx_size"] );
			build.DirectXPath = (string)obj["dx_file"];
			build.OpenGLSize = Int32.Parse( (string)obj["ogl_size"] );
			build.OpenGLPath = (string)obj["ogl_file"];
			return build;
		}		
	}
}