#region Copyright & License Information
/*
* Copyright 2007-2011 The OpenRA Developers (see AUTHORS)
* This file is part of OpenRA, which is free software. It is made
* available to you under the terms of the GNU General Public License
* as published by the Free Software Foundation. For more information,
* see COPYING.
*/
#endregion

using System;
using System.Drawing;
using System.IO;
using Tao.OpenGl;
using Tao.Sdl;

namespace OpenRA.Renderer.SdlCommon
{
	public class SdlInput
	{
		MouseButton lastButtonBits = (MouseButton)0;
		IntPtr surface;

		public SdlInput( IntPtr surface ) { this.surface = surface; }

		MouseButton MakeButton( byte b )
		{
			return b == Sdl.SDL_BUTTON_LEFT ? MouseButton.Left
				: b == Sdl.SDL_BUTTON_RIGHT ? MouseButton.Right
				: b == Sdl.SDL_BUTTON_MIDDLE ? MouseButton.Middle
				: b == Sdl.SDL_BUTTON_WHEELDOWN ? MouseButton.WheelDown
				: b == Sdl.SDL_BUTTON_WHEELUP ? MouseButton.WheelUp
				: 0;
		}

		Modifiers MakeModifiers( int raw )
		{
			return ( ( raw & Sdl.KMOD_ALT ) != 0 ? Modifiers.Alt : 0 )
				 | ( ( raw & Sdl.KMOD_CTRL ) != 0 ? Modifiers.Ctrl : 0 )
				 | ( ( raw & Sdl.KMOD_META ) != 0 ? Modifiers.Meta : 0 )
				 | ( ( raw & Sdl.KMOD_SHIFT ) != 0 ? Modifiers.Shift : 0 );
		}

		public void PumpInput( IInputHandler inputHandler )
		{
			Game.HasInputFocus = 0 != ( Sdl.SDL_GetAppState() & Sdl.SDL_APPINPUTFOCUS );

			var mods = MakeModifiers( Sdl.SDL_GetModState() );
			inputHandler.ModifierKeys( mods );
			MouseInput? pendingMotion = null;

			Sdl.SDL_Event e;
			while( Sdl.SDL_PollEvent( out e ) != 0 )
			{
				switch( e.type )
				{
				case Sdl.SDL_QUIT:
					OpenRA.Game.Exit();
					break;

				case Sdl.SDL_MOUSEBUTTONDOWN:
					{
						if( pendingMotion != null )
						{
							inputHandler.OnMouseInput( pendingMotion.Value );
							pendingMotion = null;
						}

						var button = MakeButton( e.button.button );
						lastButtonBits |= button;

						inputHandler.OnMouseInput( new MouseInput(
							MouseInputEvent.Down, button, new int2( e.button.x, e.button.y ), mods, 1 ) );
					} break;

				case Sdl.SDL_MOUSEBUTTONUP:
					{
						if( pendingMotion != null )
						{
							inputHandler.OnMouseInput( pendingMotion.Value );
							pendingMotion = null;
						}

						var button = MakeButton( e.button.button );
						lastButtonBits &= ~button;

						var pos = new int2( e.button.x, e.button.y );
						inputHandler.OnMouseInput( new MouseInput(
							MouseInputEvent.Up, button, pos, mods,
							MultiTapDetection.DetectFromMouse( e.button.button, pos )));
					} break;

				case Sdl.SDL_MOUSEMOTION:
					{
						pendingMotion = new MouseInput(
							MouseInputEvent.Move,
							lastButtonBits,
							new int2( e.motion.x, e.motion.y ),
							mods, 0 );
					} break;

				case Sdl.SDL_KEYDOWN:
					{
						var keyEvent = new KeyInput
						{
							Event = KeyInputEvent.Down,
							Modifiers = mods,
							UnicodeChar = (char)e.key.keysym.unicode,
							KeyName = Sdl.SDL_GetKeyName( e.key.keysym.sym ),
							VirtKey = e.key.keysym.sym
						};

						if( !HandleSpecialKey( keyEvent ) )
							inputHandler.OnKeyInput( keyEvent );
					} break;

				case Sdl.SDL_KEYUP:
					{
						var keyEvent = new KeyInput
						{
							Event = KeyInputEvent.Up,
							Modifiers = mods,
							UnicodeChar = (char)e.key.keysym.unicode,
//							KeyName = MultiTapDetection.DetectFromKeyboard(Sdl.SDL_GetKeyName( e.key.keysym.sym )),
							KeyName = Sdl.SDL_GetKeyName( e.key.keysym.sym ),
							VirtKey = e.key.keysym.sym
						};

						inputHandler.OnKeyInput( keyEvent );
					} break;
				}
			}

			if( pendingMotion != null )
			{
				inputHandler.OnMouseInput( pendingMotion.Value );
				pendingMotion = null;
			}

			ErrorHandler.CheckGlError();
		}

		bool HandleSpecialKey( KeyInput k )
		{
			switch( k.VirtKey )
			{
			case Sdl.SDLK_F13:
				var path = Environment.GetFolderPath( Environment.SpecialFolder.Personal )
					+ Path.DirectorySeparatorChar + DateTime.UtcNow.ToString( "OpenRA-yyyy-MM-ddThhmmssZ" ) + ".bmp";
				Sdl.SDL_SaveBMP( surface, path );
				return true;

			case Sdl.SDLK_F4:
				if( k.Modifiers.HasModifier( Modifiers.Alt ) )
				{
					OpenRA.Game.Exit();
					return true;
				}
				return false;

			default:
				return false;
			}
		}
	}
}