using System.Drawing;
using System.Windows.Forms;
using OpenRa.FileFormats;
using OpenRa.Game.Graphics;
using System.Runtime.InteropServices;
using OpenRa.Game.Traits;
using System.IO;
using System;

namespace OpenRa.Game
{
	class MainWindow : Form
	{
		readonly Renderer renderer;

		static Size GetResolution(Settings settings)
		{
			var desktopResolution = Screen.PrimaryScreen.Bounds.Size;

			return new Size(
				settings.GetValue("width", desktopResolution.Width),
				settings.GetValue("height", desktopResolution.Height));
		}

		[DllImport("user32")]
		static extern int ShowCursor([MarshalAs(UnmanagedType.Bool)] bool visible);

		public MainWindow(Settings settings)
		{
			FormBorderStyle = FormBorderStyle.None;
			BackColor = Color.Black;
			StartPosition = FormStartPosition.Manual;
			Location = Point.Empty;
			Visible = true;

			UiOverlay.ShowUnitDebug = settings.GetValue("udebug", false);
			UiOverlay.ShowBuildDebug = settings.GetValue("bdebug", false);
			WorldRenderer.ShowUnitPaths = settings.GetValue("pathdebug", false);
			Game.timestep = settings.GetValue("rate", 40);
			Game.Replay = settings.GetValue("replay", "");
			Game.NetworkHost = settings.GetValue( "host", "" );
			Game.NetworkPort = int.Parse( settings.GetValue( "port", "0" ) );

			var useAftermath = bool.Parse( settings.GetValue( "aftermath", "false" ) );

			Renderer.SheetSize = int.Parse( settings.GetValue( "sheetsize", "512" ) );

			while( !File.Exists( "redalert.mix" ) )
			{
				var current = Directory.GetCurrentDirectory();
				if( Directory.GetDirectoryRoot( current ) == current )
					throw new InvalidOperationException( "Unable to load MIX files." );
				Directory.SetCurrentDirectory( ".." );
			}

			FileSystem.MountDefault( useAftermath );

			bool windowed = !settings.GetValue( "fullscreen", false );
			renderer = new Renderer( this, GetResolution( settings ), windowed );
			SheetBuilder.Initialize( renderer );

			Game.Initialize(settings.GetValue("map", "scm12ea.ini"), renderer, new int2(ClientSize),
				settings.GetValue("player", 1), useAftermath);

			SequenceProvider.ForcePrecache();

			renderer.BuildPalette( Rules.Map );
			ShowCursor(false);
			Game.ResetTimer();
		}

		internal void Run()
		{
			while (Created && Visible)
			{
				Game.Tick();
				Application.DoEvents();
			}
		}

		int2 lastPos;

		protected override void OnMouseDown(MouseEventArgs e)
		{
			base.OnMouseDown(e);
			lastPos = new int2(e.Location);

			Game.viewport.DispatchMouseInput(new MouseInput
			{
				Button = e.Button,
				Event = MouseInputEvent.Down,
				Location = new int2(e.Location)
			});
		}

		protected override void OnMouseMove(MouseEventArgs e)
		{
			base.OnMouseMove(e);

			if (e.Button == MouseButtons.Middle)
			{
				int2 p = new int2(e.Location);
				Game.viewport.Scroll(lastPos - p);
				lastPos = p;
			}

			Game.viewport.DispatchMouseInput(new MouseInput
			{
				Button = e.Button,
				Event = MouseInputEvent.Move,
				Location = new int2(e.Location)
			});
		}

		protected override void OnMouseUp(MouseEventArgs e)
		{
			base.OnMouseUp(e);

			Game.viewport.DispatchMouseInput(new MouseInput
			{
				Button = e.Button,
				Event = MouseInputEvent.Up,
				Location = new int2(e.Location)
			});
		}

		protected override void OnKeyPress(KeyPressEventArgs e)
		{
			base.OnKeyPress(e);

			if (e.KeyChar == '\r')
				Game.chat.Toggle();
			else if (Game.chat.isChatting)
				Game.chat.TypeChar(e.KeyChar);
		}
	}

	struct MouseInput
	{
		public MouseInputEvent Event;
		public int2 Location;
		public MouseButtons Button;
	}

	enum MouseInputEvent { Down, Move, Up };
}