// Caching picture
if (document.images)
{
	none = new Image(); none.src = "img/none.gif";
	wall = new Image(); wall.src = ""; 
	man = new Image();  man.src = "img/hd.gif";
	manok = new Image(); manok.src = "img/hdok.gif";
	paket = new Image(); paket.src = "img/paket.gif";
	paketok = new Image(); paketok.src = "img/paketok.gif";
	place = new Image(); place.src = "img/place.gif";
}

// Arrow keys
var left = 37, up = 38, right = 39, down = 40;
// Constants
var none = none.src, wall = wall.src, man = man.src, manok = manok.src, paket = paket.src, paketok = paketok.src, place = place.src;
var noneCode = "0", wallCode = "1", manCode = "5", manokCode = "6", paketCode = "2", paketokCode = "4", placeCode = "3";
// Record all moves
var moves = new String("");
// First shot
var FirstView = new Array();
// Play solution
var IsPlaySolution = false;



function getOfs(way) {
var ofs = 0;

	if (way == "r") return ofs+1;
	if (way == "l") return ofs-1;
	if (way == "u") return ofs-= X;
	if (way == "d") return ofs+= X;
};

function init() 
{
	document.onkeydown = register;
	
	function register(e)
	{
		if ( (e.keyCode == left) || (e.keyCode == right) || (e.keyCode == up) || (e.keyCode == down) ) {
			// Check is play now solution
			if (IsPlaySolution) return false;
			move(e.keyCode);
			checkEndGame();
			return false;
		} else {
			return true;
		}
	}
};

function isWall(way, poz) {
var ofs = 0;

	ofs = getOfs(way);

	if ((Level.charAt(poz + ofs)) != wallCode) 
		return false
	else 
		return true;
};

function isPaket(way, poz) {
var ofs = 0;
	
	ofs = getOfs(way);
	
	if (document.images["board"+(poz + ofs)].src.indexOf(paket, 0) == -1)
		return false;
	else 
		return true;
};

function isPaketOK(way, poz) {
var ofs = 0;
	
	ofs = getOfs(way);
	
	if (document.images["board"+(poz + ofs)].src.indexOf(paketok, 0) == -1)
		return false;
	else 
		return true;
};

function isPlace(way, poz) {
var ofs = 0;
	
	ofs = getOfs(way);
	
	if ((Level.charAt(poz + ofs)) != placeCode)
		return false;
	else 
		return true;
};

function getPlace(poz) {
	if (Level.charAt(poz) == noneCode )
		return none;
	if (Level.charAt(poz) == placeCode )
		return place;
	return none;
};

function upKey(key) {
	document.PlayLevel.allMoves.value++;
	moves+=key;
};

function move(key) {
// Move RIGHT
	if (key == right) {
		if (isPaket( "r", lastMove) || isPaketOK( "r", lastMove))
      {
			if ((!isWall( "r", lastMove+1)) && (!isPaket("r", lastMove+1)) && (!isPaketOK("r", lastMove+1))) {
				document.images["board"+lastMove].src = getPlace(lastMove);
				lastMove++;
				if (isPlace("r", lastMove-1))
					document.images["board"+lastMove].src = manok;
				else
					document.images["board"+lastMove].src = man;
				if (isPlace("r", lastMove)) {
					//lastEl = place;
					document.images["board"+(lastMove+1)].src = paketok;
				}
				else {
					document.images["board"+(lastMove+1)].src = paket;
					//lastEl = none;
				}
				upKey("r");
			};
			return;
		};
		if (!isWall("r", lastMove))
      {
			document.images["board"+lastMove].src = getPlace(lastMove);
			lastMove++;
			if (isPlace("r", lastMove-1))
				document.images["board"+lastMove].src = manok;
			else
				document.images["board"+lastMove].src = man;
			upKey("r");
		}	
		return;
	};
// Move LEFT	
	if (key == left) {
		if (isPaket( "l", lastMove) || isPaketOK( "l", lastMove)) {
			if ((!isWall( "l", lastMove-1)) && (!isPaket("l", lastMove-1)) && (!isPaketOK("l", lastMove-1))) {
				document.images["board"+lastMove].src = getPlace(lastMove);
				lastMove--;
				if (isPlace("l", lastMove+1))
					document.images["board"+lastMove].src = manok;
				else
					document.images["board"+lastMove].src = man;
				if (isPlace("l", lastMove)) {
					//lastEl = place;
					document.images["board"+(lastMove-1)].src = paketok;
				}
				else {
					document.images["board"+(lastMove-1)].src = paket;
					//lastEl = none;
				}
				upKey("l");
			};
			return;
		};
		
		if (!isWall("l", lastMove)) {
			document.images["board"+lastMove].src = getPlace(lastMove);
			lastMove--;
			if (isPlace("l", lastMove+1))
				document.images["board"+lastMove].src = manok;
			else
				document.images["board"+lastMove].src = man;
			upKey("l");
		}
		
			
		return;
	};
// Move UP	
	if (key == up) {
		if (isPaket( "u", lastMove) || isPaketOK( "u", lastMove)) {
			if ((!isWall( "u", lastMove-X)) && (!isPaket("u", lastMove-X)) && (!isPaketOK("u", lastMove-X))) {
				document.images["board"+lastMove].src = getPlace(lastMove);
				lastMove-=X;
				if (isPlace("u", lastMove+X))
					document.images["board"+lastMove].src = manok
				else
					document.images["board"+lastMove].src = man;
				if (isPlace("u", lastMove)) {
					//lastEl = place;
					document.images["board"+(lastMove-X)].src = paketok;
				}
				else {
					document.images["board"+(lastMove-X)].src = paket;
					//lastEl = none;
				}
				upKey("u");
			};
			return;
		};
		if (!isWall("u", lastMove)) {
			document.images["board"+lastMove].src = getPlace(lastMove);
			lastMove-=X;
			if (isPlace("u", lastMove+X))
				document.images["board"+lastMove].src = manok;
			else
				document.images["board"+lastMove].src = man;
			upKey("u");
		}	
		return;
	};
// Move DOWN	
	if (key == down) {
		if (isPaket( "d", lastMove) || isPaketOK( "d", lastMove)) {
			if ((!isWall( "d", lastMove+X)) && (!isPaket("d", lastMove+X)) && (!isPaketOK("d", lastMove+X))) {
				document.images["board"+lastMove].src = getPlace(lastMove);
				lastMove+=X;
				if (isPlace("d", lastMove-X))
					document.images["board"+lastMove].src = manok;
				else
					document.images["board"+lastMove].src = man;
				if (isPlace("d", lastMove)) {
					//lastEl = place;
					document.images["board"+(lastMove+X)].src = paketok;
				}
				else {
					document.images["board"+(lastMove+X)].src = paket;
					//lastEl = none;
				}
				upKey("d");
			};
			return;
		};
		if (!isWall("d", lastMove)) {
			document.images["board"+lastMove].src = getPlace(lastMove);
			lastMove+=X;
			if (isPlace("d", lastMove-X))
				document.images["board"+lastMove].src = manok;
			else
				document.images["board"+lastMove].src = man;
			upKey("d");
		}	
		return;
	};
};

function checkEndGame() {
	
   for (i = 0; i < Level.length; i++) {
		if (Level.charAt(i) == placeCode) {
			// Level is't ready
			if (document.images["board"+i].src.indexOf(paketok, 0) == -1)
				return false;
		};
	};
// Level is completed	
	//alert('              Well done :) \r\nYou solved the level for '+moves.length+' moves.');
   
    document.PlayLevel.solution.value = moves;
	document.PlayLevel.submit();
   
//	resetLevel();
};

var br = 0;

function FirstViewOfLevel()
{
	for (i = 0; i < Level.length; i++)
	{
		FirstView[i] = document.getElementById("board"+i).src;
	}
};

function resetLevel()
{
	for (i = 0; i < Level.length; i++) 
	{
		document.getElementById("board"+i).src =FirstView[i];
		if (Level.charAt(i) == 4 || Level.charAt(i) == 6) 
		{
			Level = Level.slice(0,i) + "3" + Level.slice(i+1, Level.length);
		};
	};
	lastMove = startPos;
	document.PlayLevel.allMoves.value = 0;
	br = 0;
	moves = "";
   IsPlaySolution = false;
};

function getKey(k) 
{
	if (k == "l") return 37;
	if (k == "u") return 38;
	if (k == "r") return 39;
	if (k == "d") return 40;
};

function solutionLevel() {

	if (solution == "")
	{ 
		alert("Not find solution !");
		return;
	}
   // Disable key input
   IsPlaySolution = true;
   // Disable button
   document.PlayLevel.btnUndo.disabled = true;
   document.PlayLevel.btnSolution.disabled = true;
   document.PlayLevel.btnReset.disabled = true;
	move(getKey(solution.charAt(br)));
	br++;
	if (br < solution.length)
      setTimeout("solutionLevel()", 100);
   else
   {
   // Enable button
      document.PlayLevel.btnUndo.disabled = false;
      document.PlayLevel.btnSolution.disabled = false;
      document.PlayLevel.btnReset.disabled = false;
      document.PlayLevel.btnUndo.focus();
   }
};

function undoMoves()
{
	var movesCopy = moves;

	resetLevel();
	for (i = 0; i < (movesCopy.length-1); i++) {
		move(getKey(movesCopy.charAt(i)));
	};
	
};

function AskBeforeChangeLevel()
{
   if (moves.length <= 0)
	{
      return true;
   }
   else
      // All unsaved data will be lost!
      return confirm('');
};