dojo.provide("acf.CheckerBoard");

dojo.require("acf.Board");

dojo.declare("acf.CheckerBoard",[acf.Board], {
  constructor: function() {
    this.position = this.emptyPosition;
    this.move = 'b';
  },
  // Playable squares (l - light, d - dark, b - both, n - neither)
  playableSquares: 'd',
  // PDN (portable draughts notation) string for a position
  fen: '',
  // String position, each playable square is a character
  // w - white man, W - white king, b - black man, B - black king, . - empty
  position: '',
  // Array of all positions
  positionList: null,
  // Whose move it is (w or b)
  move: '',
  // Array of all moves
  moveList: null,
  // Default starting position for 8x8 checkers
  defaultPosition: 'bbbbbbbbbbbb........wwwwwwwwwwww',
  // Empty 8x8 board
  emptyPosition: '................................',
  // Image for White man
  wmImg: dojo.moduleUrl("acf","resources/images/wm.gif"),
  // Image for Black man
  bmImg: dojo.moduleUrl("acf","resources/images/bm.gif"),
  // Image for White king
  wkImg: dojo.moduleUrl("acf","resources/images/wk.gif"),
  // Image for Black king
  bkImg: dojo.moduleUrl("acf","resources/images/bk.gif"),

  // Image for Deleting pieces
  delImg: dojo.moduleUrl("acf","resources/images/trash_can.png"),

  drawPosition: function() {
    var p = this.position;
    for(var i = 0; i < p.length; i++) {
      var s = 'square_'+(i+1);
      dojo.attr(this[s],'value',p[i]);
      // Empty all squares before re-adding pieces
      if(this[s].hasChildNodes()) {
        dojo.empty(this[s]);
      }
      switch(p[i]) {
        case 'b':
          dojo.query(dojo.create('img',{src: this.bmImg})).place(this[s]);
//TODO only do this in the correct mode
          // Sync the DnD
          this[s].dnd.sync();
          break;
        case 'B':
          dojo.query(dojo.create('img',{src: this.bkImg})).place(this[s]);
//TODO only do this in the correct mode
          // Sync the DnD
          this[s].dnd.sync();
          break;
        case 'w':
          dojo.query(dojo.create('img',{src: this.wmImg})).place(this[s]);
//TODO only do this in the correct mode
          // Sync the DnD
          this[s].dnd.sync();
          break;
        case 'W':
          dojo.query(dojo.create('img',{src: this.wkImg})).place(this[s]);
//TODO only do this in the correct mode
          // Sync the DnD
          this[s].dnd.sync();
          break;
        default: 
          break;
      }
    }
  },

  // Determine if this square should accept the incoming piece
  _isAccepted: function(p_source,p_nodes) {
    // Check board mode
    // Check space against piece
    var s = this.square;
    var p = dojo.attr(p_nodes[0],'value');
/*
    console.log(s);
    console.log(p);
*/
    return true;
  },

  // On drop of a piece, set some values 
  _doDrop: function(p_source,p_nodes,p_copy,p_target) {
    if(dojo.dnd.manager().target !== this) {
      return;
    }
    var s = this.square;
    var p = dojo.attr(p_nodes[0],'value');
    // If not copying, we are moving around on the board
    // Need to unset the value on the from square
    if(!p_copy) {
      var f = p_source.square;
      this.board._setPiece(f,'.');
    }
/*
    console.log(s);
    console.log(p);
*/
    this.board._setPiece(s,p);
  },

  // Change the current position
  _setPiece: function(p_square,p_value) {
// Borrowed regex expression to replace 1 char from
// http://bytes.com/topic/javascript/answers/771950-change-single-character-string
// string[num] = 'new string'; does not work
    var p = this.position;
    var re = new RegExp('^(.{'+ --p_square +'}).(.*)$','');
    this.position = p.replace(re,'$1'+p_value+'$2');
  },

  generateFEN: function() {
    var s = this.move.toUpperCase();
    var w = '';
    var b = '';
    var p = this.position;
    for(var i = 0; i < p.length; i++) {
      var sq = i+1;
      switch(p[i]) {
        case 'w':
          w += sq+',';
          break;
        case 'W':
          w += 'K'+sq+',';
          break;
        case 'b':
          b += sq+',';
          break;
        case 'B':
          b += 'K'+sq+',';
          break;
        default:
          break;
      }
    }
    w = w.replace(/\,$/,"")
    b = b.replace(/\,$/,"")
    s += ':W'+w+':B'+b;
    this.fen = s;
  },

  flipBoard: function() {
    var b = (this._board) ? this._board : this;
    b._flipBoard();
    b.drawPosition();
  },

  _removeBank: function() {
    var b = this.bank;
    if(b.hasChildNodes()) {
      dojo.empty(b);
    }
    b.style.display = 'block';
  },

  _createBank: function() {
    var b = this.bank;
    b.style.backgroundImage = 'url('+this.bankImg+')';
    if(b.hasChildNodes()) {
      dojo.empty(b);
    }
//TODO don't allow pieces to overlap
    var x = new dojo.dnd.Source(b,{copyOnly: true});
    x.accept = null;
//
    var s = dojo.create('div');
    dojo.attr(s,'value','w');
    dojo.addClass(s,'dojoDndItem piece');
    dojo.query(dojo.create('img',{src: this.wmImg})).place(s);
    dojo.place(s,b);
//
    s = dojo.create('div');
    dojo.attr(s,'value','b');
    dojo.addClass(s,'dojoDndItem piece');
    dojo.query(dojo.create('img',{src: this.bmImg})).place(s);
    dojo.place(s,b);
//
    s = dojo.create('div');
    dojo.attr(s,'value','W');
    dojo.addClass(s,'dojoDndItem piece');
    dojo.query(dojo.create('img',{src: this.wkImg})).place(s);
    dojo.place(s,b);
//
    s = dojo.create('div');
    dojo.attr(s,'value','B');
    dojo.addClass(s,'dojoDndItem piece');
    dojo.query(dojo.create('img',{src: this.bkImg})).place(s);
    dojo.place(s,b);
//
    var t = dojo.create('div');
    t.style.width = s.offsetWidth;
    var y = new dojo.dnd.Source(t,{isSource: false});
    var i = dojo.create('img',{src: this.delImg});
    i.style.width = s.offsetWidth;
    i.style.height = s.offsetHeight;
    dojo.place(i,t);
    dojo.place(t,b);
    // Delete all nodes on drop
    dojo.connect(y,"onDndDrop",function () {
      this.deleteSelectedNodes();
    });
    y.startup();
//
    x.startup();
    b.style.display = 'table-cell';
    this._resize();
  },

  postCreate: function() {
// Have to do this here because constructor doesn't read html yet
    if(!this.cols) {
      this.cols = this.rows;
    }
    this._createBoard();
    this._createToolbar();
    this.toggleNumbers(this.showNumbers);
    this._createBank();
  }

});