// Copyright 2011 David Galles, University of San Francisco. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other materials
// provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``AS IS'' AND ANY EXPRESS OR IMPLIED
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
// FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
// ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// The views and conclusions contained in the software and documentation are those of the
// authors and should not be interpreted as representing official policies, either expressed
// or implied, of the University of San Francisco


var LINKED_LIST_START_X = 100;
var LINKED_LIST_START_Y = 200;
var LINKED_LIST_ELEM_WIDTH = 70;
var LINKED_LIST_ELEM_HEIGHT = 30;


var LINKED_LIST_INSERT_X = 250;
var LINKED_LIST_INSERT_Y = 50;

var LINKED_LIST_ELEMS_PER_LINE = 8;
var LINKED_LIST_ELEM_SPACING = 100;
var LINKED_LIST_LINE_SPACING = 100;

var TOP_POS_X = 180;
var TOP_POS_Y = 100;
var TOP_LABEL_X = 130;
var TOP_LABEL_Y =  100;

var TOP_ELEM_WIDTH = 30;
var TOP_ELEM_HEIGHT = 30;

var TAIL_POS_X = 180;
var TAIL_LABEL_X = 130;

var PUSH_LABEL_X = 50;
var PUSH_LABEL_Y = 30;
var PUSH_ELEMENT_X = 120;
var PUSH_ELEMENT_Y = 30;

var SIZE = 32;

function QueueLL(am, w, h)
{
	this.init(am, w, h);
	
}

QueueLL.prototype = new Algorithm();
QueueLL.prototype.constructor = QueueLL;
QueueLL.superclass = Algorithm.prototype;


QueueLL.prototype.init = function(am, w, h)
{
	QueueLL.superclass.init.call(this, am, w, h);
	this.addControls();
	this.nextIndex = 0;
	this.commands = [];
	this.tail_pos_y = h - LINKED_LIST_ELEM_HEIGHT;
	this.tail_label_y = this.tail_pos_y;
	this.setup();
	this.initialIndex = this.nextIndex;
}


QueueLL.prototype.addControls =  function()
{
	this.controls = [];
	this.enqueueField = addControlToAlgorithmBar("Text", "");
	this.enqueueField.onkeydown = this.returnSubmit(this.enqueueField,  this.enqueueCallback.bind(this), 6);
	this.enqueueButton = addControlToAlgorithmBar("Button", "Enqueue");
	this.enqueueButton.onclick = this.enqueueCallback.bind(this);
	this.controls.push(this.enqueueField);
	this.controls.push(this.enqueueButton);

	this.dequeueButton = addControlToAlgorithmBar("Button", "Dequeue");
	this.dequeueButton.onclick = this.dequeueCallback.bind(this);
	this.controls.push(this.dequeueButton);
	
	this.clearButton = addControlToAlgorithmBar("Button", "Clear Queue");
	this.clearButton.onclick = this.clearCallback.bind(this);
	this.controls.push(this.clearButton);
	
}

QueueLL.prototype.enableUI = function(event)
{
	for (var i = 0; i < this.controls.length; i++)
	{
		this.controls[i].disabled = false;
	}
	
	
}
QueueLL.prototype.disableUI = function(event)
{
	for (var i = 0; i < this.controls.length; i++)
	{
		this.controls[i].disabled = true;
	}
}


QueueLL.prototype.setup = function()
{
	
	this.linkedListElemID = new Array(SIZE);
	for (var i = 0; i < SIZE; i++)
	{
		
		this.linkedListElemID[i]= this.nextIndex++;
	}
	this.headID = this.nextIndex++;
	this.headLabelID = this.nextIndex++;

	this.tailID = this.nextIndex++;
	this.tailLabelID = this.nextIndex++;

	
	this.arrayData = new Array(SIZE);
	this.top = 0;
	this.leftoverLabelID = this.nextIndex++;
	
	this.cmd("CreateLabel", this.headLabelID, "Head", TOP_LABEL_X, TOP_LABEL_Y);
	this.cmd("CreateRectangle", this.headID, "", TOP_ELEM_WIDTH, TOP_ELEM_HEIGHT, TOP_POS_X, TOP_POS_Y);
	this.cmd("SetNull", this.headID, 1);
	
	
	this.cmd("CreateLabel", this.tailLabelID, "Tail", TAIL_LABEL_X, this.tail_label_y);
	this.cmd("CreateRectangle", this.tailID, "", TOP_ELEM_WIDTH, TOP_ELEM_HEIGHT, TAIL_POS_X, this.tail_pos_y);
	this.cmd("SetNull", this.tailID, 1);
	
	this.cmd("CreateLabel", this.leftoverLabelID, "", 5, PUSH_LABEL_Y,0);
	
	
	this.animationManager.StartNewAnimation(this.commands);
	this.animationManager.skipForward();
	this.animationManager.clearHistory();		
	
}

QueueLL.prototype.resetLinkedListPositions = function()
{
	for (var i = this.top - 1; i >= 0; i--)
	{
		var nextX = (this.top - 1 - i) % LINKED_LIST_ELEMS_PER_LINE * LINKED_LIST_ELEM_SPACING + LINKED_LIST_START_X;
		var nextY = Math.floor((this.top - 1 - i) / LINKED_LIST_ELEMS_PER_LINE) * LINKED_LIST_LINE_SPACING + LINKED_LIST_START_Y;
		this.cmd("Move", this.linkedListElemID[i], nextX, nextY);				
	}
	
}


		
		
QueueLL.prototype.reset = function()
{
	this.top = 0;
	this.nextIndex = this.initialIndex;

}
		
		
QueueLL.prototype.enqueueCallback = function(event)
{
	if (this.top < SIZE && this.enqueueField.value != "")
	{
		var pushVal = this.enqueueField.value;
		this.enqueueField.value = ""
		this.implementAction(this.enqueue.bind(this), pushVal);
	}
}
		
		
QueueLL.prototype.dequeueCallback = function(event)
{
	if (this.top > 0)
	{
		this.implementAction(this.dequeue.bind(this), "");
	}
}
		

QueueLL.prototype.clearCallback = function(event)
{
	this.implementAction(this.clearData.bind(this), "");
}

		

QueueLL.prototype.enqueue = function(elemToPush)
{
	this.commands = new Array();
	
	this.arrayData[this.top] = elemToPush;
	
	this.cmd("SetText", this.leftoverLabelID, "");
	
	for (var i  = this.top; i > 0; i--)
	{
		this.arrayData[i] = this.arrayData[i-1];
		this.linkedListElemID[i] =this.linkedListElemID[i-1];
	}
	this.arrayData[0] = elemToPush;
	this.linkedListElemID[0] = this.nextIndex++;
	
	var labPushID = this.nextIndex++;
	var labPushValID = this.nextIndex++;
	this.cmd("CreateLinkedList",this.linkedListElemID[0], "" ,LINKED_LIST_ELEM_WIDTH, LINKED_LIST_ELEM_HEIGHT, 
		LINKED_LIST_INSERT_X, LINKED_LIST_INSERT_Y, 0.25, 0, 1, 1);
	
	this.cmd("SetNull", this.linkedListElemID[0], 1);
	this.cmd("CreateLabel", labPushID, "Enqueuing Value: ", PUSH_LABEL_X, PUSH_LABEL_Y);
	this.cmd("CreateLabel", labPushValID,elemToPush, PUSH_ELEMENT_X, PUSH_ELEMENT_Y);
	
	this.cmd("Step");
	
	
	
	this.cmd("Move", labPushValID, LINKED_LIST_INSERT_X, LINKED_LIST_INSERT_Y);
	
	this.cmd("Step");
	this.cmd("SetText", this.linkedListElemID[0], elemToPush);
	this.cmd("Delete", labPushValID);
	
	if (this.top == 0)
	{
		this.cmd("SetNull", this.headID, 0);
		this.cmd("SetNull", this.tailID, 0);
		this.cmd("connect", this.headID, this.linkedListElemID[this.top]);
		this.cmd("connect", this.tailID, this.linkedListElemID[this.top]);
	}
	else
	{
		this.cmd("SetNull", this.linkedListElemID[1], 0);
		this.cmd("Connect",  this.linkedListElemID[1], this.linkedListElemID[0]);
		this.cmd("Step");
		this.cmd("Disconnect", this.tailID, this.linkedListElemID[1]);
	}
	this.cmd("Connect", this.tailID, this.linkedListElemID[0]);
	
	this.cmd("Step");
	this.top = this.top + 1;
	this.resetLinkedListPositions();
	this.cmd("Delete", labPushID);
	this.cmd("Step");
	
	return this.commands;
}

QueueLL.prototype.dequeue = function(ignored)
{
	this.commands = new Array();
	
	var labPopID = this.nextIndex++;
	var labPopValID = this.nextIndex++;
	
	this.cmd("SetText", this.leftoverLabelID, "");
	
	
	this.cmd("CreateLabel", labPopID, "Dequeued Value: ", PUSH_LABEL_X, PUSH_LABEL_Y);
	this.cmd("CreateLabel", labPopValID,this.arrayData[this.top - 1], LINKED_LIST_START_X, LINKED_LIST_START_Y);
	
	this.cmd("Move", labPopValID,  PUSH_ELEMENT_X, PUSH_ELEMENT_Y);
	this.cmd("Step");
	this.cmd("Disconnect", this.headID, this.linkedListElemID[this.top - 1]);
	
	if (this.top == 1)
	{
		this.cmd("SetNull", this.headID, 1);
		this.cmd("SetNull", this.tailID, 1);
		this.cmd("Disconnect", this.tailID, this.linkedListElemID[this.top-1]);
	}
	else
	{
		this.cmd("Connect", this.headID, this.linkedListElemID[this.top-2]);
	}
	this.cmd("Step");
	this.cmd("Delete", this.linkedListElemID[this.top - 1]);
	this.top = this.top - 1;
	this.resetLinkedListPositions();
	
	this.cmd("Delete", labPopValID)
	this.cmd("Delete", labPopID);
	this.cmd("SetText", this.leftoverLabelID, "Dequeued Value: " + this.arrayData[this.top]);
	
	
	
	return this.commands;
}



QueueLL.prototype.clearAll = function()
{
	this.commands = new Array();
	for (var i = 0; i < this.top; i++)
	{
		this.cmd("Delete", this.linkedListElemID[i]);
	}
	this.top = 0;
	this.cmd("SetNull", this.headID, 1);
	return this.commands;
	
}


var currentAlg;

function init()
{
	var animManag = initCanvas();
	currentAlg = new QueueLL(animManag, canvas.width, canvas.height);
}