// declaration of the array that will contain the game
field = Array();
// number of frames to pass before inserting a new row
interval = 50;
// tiles placed so far
tiles_placed = 0;
// loop that initializes the field
for (x=0; x<10; x++) {
	field[x] = Array();
	for (y=0; y<10; y++) {
		field[x][y] = 0;
	}
}
// function that places a line of tiles in the bottom of the field
function place_line() {
	for (x=0; x<10; x++) {
		tiles_placed++;
		// if the spot is not empty, must shift the colum
		if (field[x][0] != 0) {
			push_blocks(x);
		}
		tile = attachMovie("tile", "tile_"+tiles_placed, tiles_placed, {_x:10+32*x, _y:300});
		num = Math.floor(Math.random()*8)+1;
		tile.gotoAndStop(num);
		field[x][0] = tiles_placed;
	}
}
// function to be executed at every frame
_root.onEnterFrame = function() {
	interval--;
	if (interval == 0) {
		interval = 50;
		place_line();
	}
};
// function that shifts the column of blocks
function push_blocks(col_number) {
	for (i=9; i>=0; i--) {
		if (field[col_number][i] != 0) {
			if (i != 9) {
				field[col_number][i+1] = field[col_number][i];
				_root["tile_"+field[col_number][i]]._y -= 32;
			} else {
				// if I have more than 10 blocks in a column, remove the 10th block
				// In a normal game, it would be "game over"
				_root["tile_"+field[col_number][i]].removeMovieClip();
			}
		}
	}
}
// when the player clicks...
onMouseDown = function () {
	// obtain tile clicked according to mouse position
	x_tile_clicked = Math.floor((_root._xmouse-10)/32);
	y_tile_clicked = -Math.floor((_root._ymouse-300)/32);
	if ((x_tile_clicked>=0) and (x_tile_clicked<=9) and (y_tile_clicked>=0) and (y_tile_clicked<=9)) {
		if (field[x_tile_clicked][y_tile_clicked] != 0) {
			remove_tiles(x_tile_clicked, y_tile_clicked, 1);
			update_field();
		}
	}
};
// removing tiles of the same color of the one clicked
function remove_tiles(tx, ty, clicked) {
	// checking tile color according to its current frame
	tile_type = _root["tile_"+field[tx][ty]]._currentframe;
	// check if the tile to remove is the one you clicked. In this case, wait to have at least two tiles to remove
	if (!clicked) {
		_root["tile_"+field[tx][ty]].removeMovieClip();
		field[tx][ty] = 0;
	}
	if ((field[tx+1][ty] != 0) and (_root["tile_"+field[tx+1][ty]]._currentframe == tile_type)) {
		remove_tiles(tx+1, ty);
	}
	if ((field[tx-1][ty] != 0) and (_root["tile_"+field[tx-1][ty]]._currentframe == tile_type)) {
		remove_tiles(tx-1, ty);
	}
	if ((field[tx][ty+1] != 0) and (_root["tile_"+field[tx][ty+1]]._currentframe == tile_type)) {
		remove_tiles(tx, ty+1);
	}
	if ((field[tx][ty-1] != 0) and (_root["tile_"+field[tx][ty-1]]._currentframe == tile_type)) {
		remove_tiles(tx, ty-1);
	}
}
// update the field, making tiles fall if bottom tiles disappear
function update_field() {
	for (i=0; i<10; i++) {
		for (j=1; j<10; j++) {
			if ((field[i][j] != 0) and (field[i][j-1] == 0)) {
				falling = j-1;
				while ((field[i][falling] == 0) and (falling>=0)) {
					field[i][falling] = field[i][falling+1];
					_root["tile_"+field[i][falling+1]]._y += 32;
					field[i][falling+1] = 0;
					falling--;
				}
			}
		}
	}
}