/*

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

var svgns   = "http://www.w3.org/2000/svg";
var xlinkns = "http://www.w3.org/1999/xlink";

function Pile(board, x, y, w, h, dx, dy, pdx, pdy) {
  this.board = board;
  this.doc   = board.doc;
  this.index = board.thePiles.length;

  board.thePiles.push(this);
  this.g = this.doc.createElementNS(svgns, "g");
  this.g.setAttribute("id", "pile-"+this.index);
  this.g.addEventListener("mousedown", new PileMouseDownHandler(this), false);
  this.g.addEventListener("click", new PileClickHandler(this), false);

  this.base = this.doc.createElementNS(svgns, "rect");
  this.base.setAttribute("x", ""+x);
  this.base.setAttribute("y", ""+y);
  this.base.setAttribute("width", ""+w);
  this.base.setAttribute("height", ""+h);
  this.base.setAttribute("style", "visibility:hidden; pointer-events:fill");
  this.g.appendChild(this.base);

  board.boardGroup.appendChild(this.g);
  this.x = x;
  this.y = y;
  this.width = w;
  this.height = h;
  this.dx = dx;
  this.dy = dy;
  this.pdx = pdx;
  this.pdy = pdy;
  this.cards = new Array();
  var me = this;
}

Pile.prototype.addCard = function(card) {
  if (card.pile) {
    card.pile.removeCard(card);
  }
  var len = this.cards.length;
  if ((this.pdx != 0) || (this.pdy !=0)) {
    for (var i=0; i<len; i++) {
      this.cards[i].setPos(this.x+this.pdx*len+this.dx*i,
                           this.y+this.pdy*len+this.dy*i);
    }
  }
  card.pile = this;
  this.cards[len] = card;
  card.rect.style.setProperty("pointer-events", "fill", "");
  card.setPos(this.x+this.pdx*len+this.dx*len,
              this.y+this.pdy*len+this.dy*len);
  this.g.appendChild(card.getElem());
}

Pile.prototype.removeCard = function(card) {
  if (this != card.pile) return;
  var len = this.cards.length;
  for (var i=len-1; i>=0; i--) {
    var c = this.cards[i];
    if (c == card) {
      this.cards.splice(i, 1);
      len = this.cards.length;
      for (var j=i; j<len; j++) {
        c = this.cards[j];
        c.setPos(this.x+this.dx*j, this.y+this.dy*j);
      }
      card.pile = null;
      break;
    }
  }
  if ((this.pdx != 0) || (this.pdy !=0)) {
    var len = this.cards.length;
    var x = this.x+this.pdx*(len-1);
    var y = this.y+this.pdy*(len-1);
    for (var i=0; i<len; i++) {
      this.cards[i].setPos(x+this.dx*i, y+this.dy*i);
    }
  }
}

Pile.prototype.moveCardTo = function(card, step) {
  if (card.pile) {
    card.pile.removeCard(card);
  }
  var len = this.cards.length;
  card.pile = this;
  this.cards.push(card);
  card.rect.style.setProperty("pointer-events", "fill", "");
  this.board.moveGroup.appendChild(card.getElem());
  var x = this.x+this.pdx*len;
  var y = this.y+this.pdy*len;
  card.moveTo(x+this.dx*len, y+this.dy*len, step);
}

Pile.prototype.moveCardsTo = function(cards, step) {
  var xlocs = new Array();
  var ylocs = new Array();
  for (var i=0; i<cards.length; i++) {
    xlocs[i] = cards[i].x;
    ylocs[i] = cards[i].y;
  }

  for (var i=0; i<cards.length; i++) {
    var card = cards[i];
    if (card.pile) {
      card.pile.removeCard(card);
    }
    card.setPos(xlocs[i], ylocs[i]);
    var len = this.cards.length;
    card.pile = this;
    this.cards.push(card);
    card.rect.style.setProperty("pointer-events", "fill", "");
    this.board.moveGroup.appendChild(card.getElem());
    var x = this.x+this.pdx*len;
    var y = this.y+this.pdy*len;
    card.moveTo(x+this.dx*len, y+this.dy*len, step);
    this.moveCardTo(card, step);
  }
}

function moveCardsToPiles(cards, piles, step) {
  var xlocs = new Array();
  var ylocs = new Array();
  for (var i=0; i<cards.length; i++) {
    xlocs[i] = cards[i].x;
    ylocs[i] = cards[i].y;
  }
  
  for (var i=0; i<cards.length; i++) {
    var card = cards[i];
    var pile = piles[i];
    if (card.pile) {
      card.pile.removeCard(card);
    }
    card.setPos(xlocs[i], ylocs[i]);
    var len = pile.cards.length;
    card.pile = pile;
    pile.cards.push(card);
    card.rect.style.setProperty("pointer-events", "fill", "");
    pile.board.moveGroup.appendChild(card.getElem());
    var x = pile.x+pile.pdx*len;
    var y = pile.y+pile.pdy*len;
    card.moveTo(x+pile.dx*len, y+pile.dy*len, step);
    pile.moveCardTo(card, step);
  }
}


Pile.prototype.size = function() {
  return this.cards.length;
}

Pile.prototype.getTopCard = function() {
  if (this.cards.length == 0) return null;
  var c = this.cards.pop();
  c.pile = null;
  if ((this.pdx != 0) || (this.pdy !=0)) {
    var len = this.cards.length;
    var x = this.x+this.pdx*(len-1);
    var y = this.y+this.pdy*(len-1);
    for (var i=0; i<len; i++) {
      this.cards[i].setPos(x+this.dx*i, y+this.dy*i);
    }
  }
  return c;
}

Pile.prototype.checkTopCard = function() {
  if (this.cards.length == 0) return null;
  return this.cards[this.cards.length-1];
}

Pile.prototype.checkCard = function(index) {
  return this.cards[index];
}

Pile.prototype.nextCard = function(card) {
  var sz = this.cards.length-1;
  for (var i=0; i<sz; i++) {
    if (this.cards[i] == card)
      return this.cards[i+1];
  }
  return null;
}

Pile.prototype.setDragCheck = function(dragCheck) {
  this.dragCheck = dragCheck;
}

Pile.prototype.setDropCheck = function(dropCheck) {
  this.dropCheck = dropCheck;
}

Pile.prototype.setClick = function(click) {
  this.click = click;
}

Pile.prototype.setDoubleClick = function(doubleClick) {
  this.doubleClick = doubleClick;
}

function PileClickHandler(pile) {
  this.pile = pile;
  this.tgt = null;
  this.clickX   =0;
  this.clickY   =0;
  this.clickCnt =0;
}

PileClickHandler.prototype.handleEvent = function(evt) {
  if (this.tgt != evt.target) {
    this.tgt = evt.target;
    this.clickX = evt.clientX;
    this.clickY = evt.clientY;
    this.clickCnt = 1;
    if (this.pile.click)
      this.pile.click(this.pile, evt);
    return;
  }
    
  var dx = evt.clientX-this.clickX;
  var dy = evt.clientY-this.clickY;
  if (dx*dx+dy*dy > 9) {
    this.clickX = evt.clientX;
    this.clickY = evt.clientY;
    this.clickCnt = 1;
    if (this.pile.click)
      this.pile.click(this.pile, evt);
    return;
  }
    
  this.clickX = evt.clientX;
  this.clickY = evt.clientY;
  this.clickCnt++;

  if (this.clickCnt > 2) {
    this.clickCnt = 1;
    if (this.pile.click)
      this.pile.click(this.pile, evt);
    return;
  }

  if (this.pile.doubleClick) {
    this.pile.doubleClick(this.pile, evt);
  }
};

function PileMouseDownHandler(pile) {
  this.pile = pile;
}

PileMouseDownHandler.prototype.handleEvent = function(evt) {
  if (!this.pile.dragCheck) return;
  var tgt = evt.target;
  var e = tgt;
  var p = e.parentNode;
  while (p && (p != this.pile.g)) {
    e = p;
    p = e.parentNode;
  }

  if (!p) return;
  var c, i;
  var num = this.pile.cards.length;
  for (i=num-1; i>=0; i--) {
    c = this.pile.cards[i];
    if (e == c.elem)
      break;
    c = null;
  }
  if (!c) return;
    
  var g = this.pile.dragCheck(this.pile, c, i);
  if (!g) return;
  var cards = this.pile.cards.splice(i, num-i);

  new CardMoveManager(g, this.pile, cards, 
                      evt.clientX, evt.clientY);
}


/**
 * Finds the pile associated with elem, if any.
 * returns null if elem is not associated with a pile.
 * otherwise it returns the associated Pile object.
 */
function findPile(board, elem) {
  var root = document.getRootElement();
  var tgt = elem
  var destPile = null;
  while (tgt != root) {
    var id;
    try { id = tgt.getAttribute("id"); } catch (x) { break; }
    if (id && id.substring(0, 5) == "pile-") {
      var idx = parseFloat(id.substring(5));
      destPile = board.thePiles[idx];
      break;
    }
    tgt = tgt.parentNode;
  }
  return destPile;
}

function CardMoveManager(group, pile, cards, x, y) {
  this.pile = pile;
  this.board = pile.board;
  this.cards = cards;
  this.group = group;
  this.parent = group.parentNode;
  this.root = this.group.getOwnerDocument().getRootElement();
  this.startPt = localPt(this.parent, x, y);
  this.fmm = new ForwardMouseMove(this);
  this.fmu = new ForwardMouseUp(this);
  this.root.addEventListener("mousemove", this.fmm, false);
  this.root.addEventListener("mouseup", this.fmu, false);
  this.moved = false;
};

CardMoveManager.prototype.mousemove = function(evt) {
  var pt = localPt(this.parent, evt.clientX, evt.clientY);
  var dx = pt.x-this.startPt.x;
  var dy = pt.y-this.startPt.y;
  if (!this.moved && ((dx*dx+dy*dy) < 4))
    return;

  if (!this.moved) {
    this.moved = true;
    // Now move cards 
    for (var i=0; i<this.cards.length; i++) {
      this.cards[i].pile = null;
      this.cards[i].rect.style.removeProperty("pointer-events");
      this.group.appendChild(this.cards[i].elem);
    }
  }
        
  this.group.setAttribute("transform", "translate(" + dx + ", " + dy + ")");
};

CardMoveManager.prototype.mouseup = function(evt) {
  this.root.removeEventListener("mousemove", this.fmm, false);
  this.root.removeEventListener("mouseup", this.fmu, false);
  this.group.setAttribute("transform","");
  if (!this.moved) {
    for (var i=0; i<this.cards.length; i++) {
      this.pile.cards.push(this.cards[i]);
    }
    return;
  }

  var pt = localPt(this.parent, evt.clientX, evt.clientY);
  var dx = pt.x-this.startPt.x;
  var dy = pt.y-this.startPt.y;

  var moveInfo = false;
  var destPile = findPile(this.board, evt.target);
  if (destPile && destPile.dropCheck) {
    moveInfo = destPile.dropCheck(this.pile, destPile, this.cards);
  }

  switch(moveInfo) {
    case true:
    // Drop succeeded but no move info.
    this.pile.board.notifyMoveDone();
    return;
    case false:
    // Drop failed move back to original.
    for (var i=0; i<this.cards.length; i++) {
      var c = this.cards[i];
      c.setPos(c.x+dx, c.y+dy);
    }
    this.pile.moveCardsTo(this.cards, 40);
    return;
    default:
    // Drop succeed record move info.
    this.pile.board.saveMove(moveInfo);
    this.pile.board.notifyMoveDone();
    return;
  }
};