exports.generate = function(width, height, bombs) {
    var map = {};

    map.original = generateField(width, height, bombs);

    map.current = [];

    for (var x = 0; x < map.original.length; x++) {
        map.current[x] = [];
        for (var y = 0; y < map.original[0].length; y++) {
            map.current[x][y] = {
                x: x,
                y: y,
                value: 0,
                type: unknown
            };
        }
    }

    return map;
};

exports.click = function(map, update, tile) {
    map.current[tile.x][tile.y] = map.original[tile.x][tile.y];

    if (map.original[tile.x][tile.y].type === bomb) {
        map.current = map.original
    }

    update(map.current);
};

var bomb = 'b';
var unknown = 'u';
var tile = 't';
var empty = 'e';

function generateField(width, height, bombs) {
    var map = [];

    var bombArray = generateBombArray(width * height, bombs);

    for (var x = 0; x < width; x++) {
        map[x] = [];
        for (var y = 0; y < height; y++) {
            map[x][y] = {};

            map[x][y].x = x;
            map[x][y].y = y;
            map[x][y].value = 0;
            map[x][y].type = tile;

            if (bombArray[x * width + y]) {
                map[x][y].type = bomb;
            }
        };
    };

    for (var x = 0; x < map.length; x++) {
        for (var y = 0; y < map[x].length; y++) {
            if (map[x][y].type === bomb) {
                around(x, y, map, function(x, y, tile) {
                    if (tile.type !== bomb) {
                        map[x][y].value++;
                    }
                })
            }
        };
    };

    return map;
};

function generateBombArray(size, bombs) {
    var pos = 0;
    var currentBombs = 0;
    var bombArray = [];

    while (currentBombs < bombs) {
        pos += Math.floor(Math.random() * size);

        if (pos > size)
            pos -= size;

        if (!bombArray[pos]) {
            bombArray[pos] = true;
            currentBombs++;
        }
    }

    return bombArray;
};

function around(x, y, map, cb) {
    for (var _x = -1; _x <= 1; _x++) {
        for (var _y = -1; _y <= 1; _y++) {
            var X = _x + x;
            var Y = _y + y;

            if (X >= 0 && Y >= 0 &&
                X < map.length && Y < map[X].length) {

            cb(X, Y, map[X][Y]);
        }
        }
    }
};