var tilesImages = [
    "./img/1.png", "./img/2.png", "./img/3.png", "./img/4.png", "./img/5.png", "./img/6.png", "./img/7.png", "./img/8.png", "./img/9.png", "./img/10.png",
    "./img/11.png", "./img/12.png", "./img/13.png", "./img/14.png", "./img/15.png", "./img/16.png", "./img/17.png", "./img/18.png", "./img/19.png", "./img/20.png"
];

//var difficulty = ""; // 1, 2 ,
var numberOfTiles = 20;
var tilesInRow = 5;
var tilesIndexArray = []; // numerek obrazka
var clickedTilesArray = []; // 2 element
var movesCount = 0;
var removedCoupleTiles = 0;
var flipAnimationEnds = true;

$(document).ready(function() {
    startNewGame();
    $('.tile').click(function() {
        $(this).flip({
            direction: 'rl',
            speed: 300
        });
    });
});

function resetGameProperties() {
    tilesIndexArray = [];
    clickedTilesArray = [];
    removedCoupleTiles = 0;
    movesCount = 0;
    flipAnimationEnds = true;
}

function generateIndexesForTiles() {
    for (var i=0; i < numberOfTiles; i++) {
        tilesIndexArray.push( Math.floor(i/2) ); // wrzucamy pary indkesów kafli 0,0,1,1..
    }
}

function populateGameField() {
    var gameField = $('#gameField');
    for (var i=0; i < numberOfTiles; i++) {
        var tile = $('<div class="tile"></div>'); // podpiac id...
        tile.data('tileIndex', i);
        tile.data('tileType', tilesIndexArray[i]);
        tile.bind('click', function() {
            tileClicked( $(this) )
        });
        gameField.append(tile);
        if ( (i+1) % tilesInRow == 0) {
            gameField.append('<br />');
        }
    }
}

/* http://bost.ocks.org/mike/shuffle/ - Fisher–Yates Shuffle */
function shuffle(array) {
    var m = array.length, t, i;

    // While there remain elements to shuffle…
    while (m) {

        // Pick a remaining element…
        i = Math.floor(Math.random() * m--);

        // And swap it with the current element.
        t = array[m];
        array[m] = array[i];
        array[i] = t;
    }

    return array;
}

function startNewGame() {

    //var gameField = $('#gameField').empty(); // czysci element i jego potomkow, tylko element - remove()

    resetGameProperties();
    generateIndexesForTiles();
    tilesIndexArray = shuffle(tilesIndexArray);
    populateGameField();

}

function tileClicked(tile) {
    if (flipAnimationEnds) {

        if (  !clickedTilesArray[0] || tile.data('tileIndex') !== clickedTilesArray[0].data('tileIndex') ) {

            clickedTilesArray.push(tile);
            console.log('url(' + tilesImages[tile.data('tileType')] + ')');
            tile.flip({
                direction: "lr",
                content:
                    tile.css({
                        'background' : 'url(' + tilesImages[tile.data('tileType')] + ')' + 'center center no-repeat'
                    }),
                speed: 150
            });

        }

        if (clickedTilesArray.length == 2) {

            flipAnimationEnds = false;
            var equalTiles = clickedTilesArray[0].data('tileType') === clickedTilesArray[1].data('tileType');
            if (equalTiles) {

            }

        }

    }
}