// Start New Game
var board;
$(document).ready(function () {
    newGame('reg');
    $('#new-game').hide();

    $('#difficulty li').click(function (eventObject) {
        $('#difficulty li').removeClass('selected');
        $(this).addClass('selected');
        var difficulty = $(this).attr('id');
        newGame(difficulty);
        $('#new-game').hide();
    });

    $('#new-game').click(function (eventObject) {
        var difficulty = $('#difficulty li.selected').attr('id');
        newGame(difficulty);
        $('#new-game').hide();
    });
});
/*
    This is equivalent to-
    $(function() {
    });
*/
function newGame(difficulty) {
   // On selection of mode, create corresponding grids.
   switch (difficulty) {
       case 'easy':
           board = new Board(6,8);
           break;
      case 'reg':
       default:
           board = new Board(8, 10);
           break;
      case 'hard':
          board = new Board(12,15);
   }
   board.render();
   board.gameOver = false;

   $('.space').click(function (eventObject) {
       board.click(eventObject.target);
   });

   return board;
}

// Board Object
function Board(row, col){
   this.row = row;
   this.col = col;
   this.spaces = [];
   this.gameOver = false;
   this.spacesCleared = 0;
   this.bombCount = 0;

   this.click = function (target_elem) {
       var row = $(target_elem).attr("data-row");
       var col = $(target_elem).attr("data-col");


       if (this.gameOver === true) {
           return;
       }

       if (this.spaces[row - 1][col - 1].explored == true) {
           return;
       }

       if (this.spaces[row - 1][col - 1].holds == -1) {
           this.explode();
       } else if (this.spaces[row - 1][col - 1].holds == 0) {
           this.clear(row - 1, col - 1);
           uncoverSurroundings.call(this, row - 1, col - 1);
       } else {
           this.clear(row - 1, col - 1);
       }
   }

   this.render = function() {
       var spaces = "";
       for (i = 1; i <= row; i++) {
           for (j = 1; j <= col; j++) {
               spaces = spaces.concat('<div class="space" data-row="' + i + '" data-col="' + j + '">&nbsp;</div>');
           }
           spaces = spaces.concat('<br />');
       }
       $('#board').empty();
       $('#board').append(spaces);
   }

   this.explode = function() {
       for (i = 0; i < this.row; i++) {
           for (j = 0; j < this.col; j++) {
               if (this.spaces[i][j].holds == -1) {
                   var dom_target = 'div[data-row="' + (i + 1) + '"][data-col="' + (j + 1) + '"]';
                   $(dom_target).addClass('bomb');
                   $(dom_target).html('<i class="fa fa-bomb"></i>');
               }
           }
       }
       this.gameOver = true;
       $('#new-game').show();
   }

   var numBombNear = function(row, col) {
       var sum = 0;

       if (this.spaces[row][col].holds == -1) {
           return -1;
       }

       sum += valueAt.call(this, row - 1, col - 1) + valueAt.call(this, row - 1, col) + valueAt.call(this, row - 1, col + 1)
           + valueAt.call(this, row, col - 1) + valueAt.call(this, row, col + 1)
           + valueAt.call(this, row + 1, col - 1) + valueAt.call(this, row + 1, col) + valueAt.call(this, row + 1, col + 1);

       return sum;
   }

   function valueAt(row, col) {
       if (row < 0 || row >= this.row || col < 0 || col >= this.col) {
           return 0;
       } else if(this.spaces[row][col].holds == -1){
           return 1;
       } else {
           return 0;
       }
   }

   //Initializing the Object

   if (this.spaces !== undefined) {
       this.spaces = new Array(this.row);

       for (i = 0; i < this.row; i++) {
           this.spaces[i] = new Array(this.col);
           for (j = 0; j < this.col; j++) {
               this.spaces[i][j] = new Space(false, 0);
           }
       }

       var min = 1;
       var max = this.row * this.col;
       this.bombCount = Math.round((Math.random() * ((max / 2) - min) + (min)));
       $('#value').html(this.bombCount);
       for (i = 0; i < this.bombCount; i++) {
           var bombIndex = Math.round(Math.random() * (max - 1));
           var x = Math.floor(bombIndex / this.col);
           var y = bombIndex % this.col;
           this.spaces[x][y] = new Space(false, -1);
       }

       for (i = 0; i < this.row; i++) {
           for (j = 0; j < this.col; j++) {
               this.spaces[i][j].holds = numBombNear.call(this, i, j);
           }
       }
   }

   this.clear = function (row, col) {
       var dom_target = 'div[data-row="' + (row + 1) + '"][data-col="' + (col + 1) + '"]';
       $(dom_target).addClass('safe');
       if (this.spaces[row][col].holds > 0) {
           $(dom_target).text(this.spaces[row][col].holds);
       } else {
           $(dom_target).html('&nbsp');
       }
       checkAllCellsExplored.call(this);
       this.spacesCleared++;
       this.spaces[row][col].explored = true;
   }

   function checkAllCellsExplored(){
       if (this.row * this.col - this.spacesCleared == this.bombCount) {
           for (i = 0; i < this.row; i++) {
               for (j = 0; j < this.col; j++) {
                   if (this.spaces[i][j].holds == -1) {
                       var bomb_target = 'div[data-row="' + (i + 1) + '"][data-col="' + (j + 1) + '"]';
                       $(bomb_target).html('<i class="fa fa-smile-o"></i>');
                       this.gameOver = true;
                       $('#new-game').show();
                   }
               }
           }
       }
   }

   function uncoverSurroundings(row, col) {
       checkSpace.call(this, row - 1, col - 1); checkSpace.call(this, row - 1, col); checkSpace.call(this, row - 1, col + 1);
       checkSpace.call(this, row, col - 1); checkSpace.call(this, row, col + 1);
       checkSpace.call(this, row + 1, col - 1); checkSpace.call(this, row + 1, col); checkSpace.call(this, row + 1, col + 1);
       checkAllCellsExplored.call(this);
   }

   function checkSpace(row, col) {
       if (row < 0 || row >= this.row || col < 0 || col >= this.col || this.spaces[row][col].explored == true) {
           return;
       } else if (this.spaces[row][col].holds >= 0) {
           this.clear(row, col);
           if (this.spaces[row][col].holds == 0) {
               uncoverSurroundings.call(this, row, col);
               return;
           }
       }
   }
}

//Space Object
function Space(explored, holds){
   this.explored = explored;
   this.holds = holds;
}