/////////////////////////////////////////////////////////////////
//
//	Tic-Tac-Toe JavaScript
//	By Premshree Pillai
//	Created : 04/10/02 (dd/mm/yy)
//	Web : http://www.qiksearch.com
//	      http://javascript.qik.cjb.net
//	E-mail : qiksearch@rediffmail.com
//		 jsfx@rediffmail.com
//	
//	Like the script ?
//	Sign my Guestbook :
//	- http://pub.alxnet.com/guestbook?id=2395118
//
//	Use freely as long as all credits are reatained
//	and all contents are as it is.
//
//	© 2002 Premshree Pillai. All rights reserved.
//	Do not modify anything below this!
//
/////////////////////////////////////////////////////////////////

/* Global Variables */
/////////////////////////////////////////////////////////////////
var playerToken="1";
var myToken="0";
var MAXSIZE=100;
var _def_size=60;
var _def_bg_color="#000000";
var _def_color="#FFFFFF";
var _def_exit_msg='<br><input type="button" class="btn" value="Play Again!" onClick="location.reload();">';

var isEmptyArr=new Array(MAXSIZE);
for(var i=0; i<isEmptyArr.length; i++)
	isEmptyArr[i]=true;
var drawCounter=0;
/* Arrays for testing */
var rowArr=new Array();
for(var i=0; i<=MAXSIZE; i++)
	rowArr[i]=0;
var colArr=new Array();
for(var i=0; i<=MAXSIZE; i++)
	colArr[i]=0;
var digArr=new Array();
for(var i=0; i<=MAXSIZE; i++)
	digArr[i]=-1;
var lostFlag=false;
var meFirst=false;
/////////////////////////////////////////////////////////////////

/* Reset Global Variables */
function flush()
{
	isEmptyArr=new Array(MAXSIZE);
	for(var i=0; i<isEmptyArr.length; i++)
		isEmptyArr[i]=true;

	rowArr=new Array();
	for(var i=0; i<=MAXSIZE; i++)
		rowArr[i]=0;
	colArr=new Array();
	for(var i=0; i<=MAXSIZE; i++)
		colArr[i]=0;
	digArr=new Array();
	for(var i=0; i<=MAXSIZE; i++)
		digArr[i]=-1;
	drawCounter=0;
	lostFlag=false;
	meFirst=false;
}

/* Generate the Board */
function genBox(size,where)
{
	var count=0;
	var retVal='<br><table>';
	for(var i=0; i<size; i++)
	{
		retVal+='<tr>';
		for(var j=0; j<size; j++)
		{
			count++;
			var id=new String('id'+count);
			retVal+='<td id="' + id + '" bgcolor="' + _def_bg_color + '" width="' + _def_size + '" height="' + _def_size + '" align="center" onClick="insert(' + playerToken + ',this.id,' + size + ')" style="font-family:comic sans ms,verdana; font-size:20pt; font-weight:bold; color:' + _def_color + '"></td>';
		}
		retVal+='</tr>';
	}
	retVal+='</table>';
	document.getElementById(where).innerHTML=retVal;
	if(isNaN(size))
	{
		alert("Please enter a valid number!");
		document.getElementById(where).innerHTML=_def_exit_msg;
	}
}

/* Insert Token */
function insert(what,id,size)
{
	var ids=id.split("id");
	if(isEmpty(id))
	{
		drawCounter++;
		document.getElementById(id).innerHTML=what;
		isEmptyArr[ids[1]]=false;
		if(what==playerToken)
			move(size);
	}
	else
		alert('You cannot insert here!');
	if((drawCounter==size*size)&&!lostFlag)
	{
		alert('It\'s a Draw!!!');
		if(confirm("Do you want to play again ?"))
		{
			flush();
			genBox(size,'container');
		}
		else
			document.getElementById('container').innerHTML=_def_exit_msg;
	}
}

/* Computer's Move! */
function move(size)
{
	var count=0;
	var maxCount=0;

	/* Building the Row Array */
	for(var i=1; i<=size; i++)
	{
		maxCount=0;
		for(var j=1; j<=size; j++)
		{
			count++;
			var id=new String('id'+count);
			if(!isEmpty(id))
				if(document.getElementById(id).innerHTML==playerToken)
					maxCount++;
		}
		rowArr[i]=maxCount;
	}

	/* Building the Column Array */
	for(var i=1; i<=size; i++)
	{
		count=i;
		maxCount=0;
		for(var j=1; j<=size; j++)
		{
			var id=new String('id'+count);
			if(!isEmpty(id))
			{
				if(document.getElementById(id).innerHTML==playerToken)
					maxCount++;
			}
			count+=size;
		}
		colArr[i]=maxCount;
	}

	/* Building the Diagonal Array */
	for(var i=1; i<=2; i++)
	{
		if(i==1)
			count=i;
		else
			count=size;
		maxCount=0;
		for(var j=1; j<=size; j++)
		{
			var id=new String('id'+count);
			if(!isEmpty(id))
			{
				if(document.getElementById(id).innerHTML==playerToken)
					maxCount++;
			}
			if(i==1)
				count+=size+1;
			else
				count+=size-1;
		}
		digArr[i]=maxCount;
	}

	/* Finding max values */
	var maxRow=max(rowArr,0,size,"row");
	var maxCol=max(colArr,0,size,"col");
	var maxDig=max(digArr,0,size,"dig");
	var maxArrs=new Array(-1,max(rowArr,1,size,"row"),max(colArr,1,size,"col"),max(digArr,1,size,"dig"));
	if(max(maxArrs,0,size,"x")==1)
		count=size*maxRow-size+1;
	if(max(maxArrs,0,size,"x")==2)
		count=maxCol;
	if(max(maxArrs,0,size,"x")==3)
	{
		if(maxDig==1)
			count=maxDig;
		else
			count=size;
	}

	if(!firstMove(size))
	{
		for(var i=1; i<=size; i++)
		{
			var id=new String('id'+count);
			if(isEmpty(id))
			{
				insert(myToken,id,size);
				break;
			}
			if(max(maxArrs,0,size,"x")==1)
				count++;
			if(max(maxArrs,0,size,"x")==2)
				count+=size;
			if(max(maxArrs,0,size,"x")==3)
			{
				if(maxDig==1)
					count+=size+1;
				else
					count+=size-1;
			}
		}
	}
	else
	{
		playFirst(size);
	}
	if(playerWin(size))
	{
		alert('WOW! You Won!!!');
		if(confirm("Do you want to play again ?"))
		{
			flush();
			genBox(size,'container');
		}
		else
			document.getElementById('container').innerHTML=_def_exit_msg;
		lostFlag=false;
	}
	else
	{
		if(checkWin(size))
		{
			alert('OOPS! You lost!!!');
			if(confirm("Do you want to play again ?"))
			{
				flush();
				genBox(size,'container');
			}
			else
				document.getElementById('container').innerHTML=_def_exit_msg;
			lostFlag=true;
		}
	}
}

function max(arr,what,size,type)
{
	var max=-1,maxIndex=-1;
	for(var i=1; i<=size; i++)
	{
		if(type=="x")
		{
			if(arr[i]>max)
			{
				max=arr[i];
				maxIndex=i;
			}
		}
		else
		{
			if(!isFull(type,i,size) && type!="dig")
			{
				if(arr[i]>max)
				{
					max=arr[i];
					maxIndex=i;
				}
			}
		}
	}
	if(type=="dig")
	{
		for(var i=1; i<=2; i++)
		{
			if(!isFull(type,i,size))
			{
				if(arr[i]>max)
				{
					max=arr[i];
					maxIndex=i;
				}
			}
		}
	}
	if(what==0)
		return(maxIndex);
	else
		return(max);
}

function isEmpty(who)
{
	who=who.split("id");
	return(isEmptyArr[who[1]]);
}

function isFull(type,num,size)
{
	var retVal,count=1;
	if(type=="row")
	{
		count=size*num-size+1;
		for(var i=1; i<=size; i++)
		{
			var id=new String('id'+count);
			if(isEmpty(id))
			{
				retVal=false;
				return false;
				break;
			}
			else
				retVal=true;
			count++;
		}
	}
	if(type=="col")
	{
		count=num;
		for(var i=1; i<=size; i++)
		{
			var id=new String('id'+count);
			if(isEmpty(id))
			{
				retVal=false
				return false;
				break;
			}
			else
				retVal=true;
			count+=size;
		}
	}
	if(type=="dig")
	{
		if(num==1)
			count=num;
		else
			count=size;
		for(var i=1; i<=size; i++)
		{
			var id=new String('id'+count);
			if(isEmpty(id))
			{
				retVal=false
				return false;
				break;
			}
			else
				retVal=true;
			if(num==1)
				count+=size+1;
			else
				count+=size-1;
		}
	}
	return(retVal);
}

function firstMove(size)
{
	var count=0;
	for(var i=1; i<=size*size; i++)
	{
		var id=new String('id'+i);
		if(!isEmpty(id))
			count++;
	}
	if(count<=1)
		return true;
	else
		return false;
}

function playFirst(size)
{
	if(size%2!=0)
	{
		var tempNum=Math.floor(size*size/2)+1;
		var id=new String('id'+tempNum);
		if(isEmpty(id))
			insert(myToken,id,size);
		else
		{
			tempNum+=size+1;
			id=new String('id'+tempNum);
			insert(myToken,id,size);
		}
	}
	else
	{
		var temp=max(digArr,0,size,"dig");
		if(temp==1)
			count=temp;
		else
			count=size;
		for(var i=1; i<=size; i++)
		{
			var id=new String('id'+count);
			if(isEmpty(id))
			{
				insert(myToken,id,size);
				break;
			}
			if(temp==1)
				count+=size+1;
			else
				count+=size-1;
		}
	}
}

function checkWin(size)
{
	var myRowArr=new Array();
	var myColArr=new Array();
	var myDigArr=new Array();
	var maxCount,count=0;

	/* Building My Row Array */
	for(var i=1; i<=size; i++)
	{
		maxCount=0;
		for(var j=1; j<=size; j++)
		{
			count++;
			var id=new String('id'+count);
			if(!isEmpty(id))
				if(document.getElementById(id).innerHTML==myToken)
					maxCount++;
		}
		myRowArr[i]=maxCount;
	}

	/* Building My Column Array */
	for(var i=1; i<=size; i++)
	{
		count=i;
		maxCount=0;
		for(var j=1; j<=size; j++)
		{
			var id=new String('id'+count);
			if(!isEmpty(id))
			{
				if(document.getElementById(id).innerHTML==myToken)
					maxCount++;
			}
			count+=size;
		}
		myColArr[i]=maxCount;
	}

	/* Building My Diagonal Array */
	for(var i=1; i<=2; i++)
	{
		if(i==1)
			count=i;
		else
			count=size;
		maxCount=0;
		for(var j=1; j<=size; j++)
		{
			var id=new String('id'+count);
			if(!isEmpty(id))
			{
				if(document.getElementById(id).innerHTML==myToken)
					maxCount++;
			}
			if(i==1)
				count+=size+1;
			else
				count+=size-1;
		}
		myDigArr[i]=maxCount;
	}
	var myMaxRow=myMax(myRowArr,0,size);
	var myMaxCol=myMax(myColArr,0,size);
	var myMaxDig=myMax(myDigArr,0,size);
	var myMaxArrs=new Array(-1,myMax(myRowArr,1,size),myMax(myColArr,1,size),myMax(myDigArr,1,size));
	if(myMax(myMaxArrs,1,size)==size)
	{
		var blinkWho=myMax(myMaxArrs,0,size);
		var blinkNum;
		if(blinkWho==1)
			blinkNum=myMaxRow;
		if(blinkWho==2)
			blinkNum=myMaxCol;
		if(blinkWho==3)
			blinkNum=myMaxDig;
		blink(blinkWho,blinkNum,size,"#FF0000");
		return true;
	}
	else
		return false;
}

function myMax(arr,what,size)
{
	var max=-1,maxIndex=-1;
	for(var i=1; i<=size; i++)
	{
		if(arr[i]>max)
		{
			max=arr[i];
			maxIndex=i;
		}
	}
	if(what==0)
		return(maxIndex);
	else
		return(max);
}

function blink(who,num,size,color)
{
	var count;
	if(who==1)
		count=size*num-size+1;
	if(who==2)
		count=num;
	if(who==3)
	{
		if(num==1)
			count=num;
		else
			count=size;
	}
	for(var i=1; i<=size; i++)
	{
		var id=new String('id'+count);
		document.getElementById(id).style.color=color;
		if(who==1)
			count++;
		if(who==2)
			count+=size;
		if(who==3)
		{
			if(num==1)
				count+=size+1;
			else
				count+=size-1;
		}
	}
}

/* Check if player wins */
function playerWin(size)
{
	var maxRow=myMax(rowArr,0,size);
	var maxCol=myMax(colArr,0,size);
	var maxDig=myMax(digArr,0,size);
	var maxArrs=new Array(-1,myMax(rowArr,1,size),myMax(colArr,1,size),myMax(digArr,1,size));
	if(myMax(maxArrs,1,size)==size)
	{
		var blinkWho=myMax(maxArrs,0,size);
		var blinkNum;
		if(blinkWho==1)
			blinkNum=maxRow;
		if(blinkWho==2)
			blinkNum=maxCol;
		if(blinkWho==3)
			blinkNum=maxDig;
		blink(blinkWho,blinkNum,size,"#00FF00");
		return true;
	}
	else
		return false;
}

function doGen()
{
	var puts;
	var size=document.containerForm.slct.options[document.forms[0].slct.options.selectedIndex].value;
	var pf=document.containerForm.slct_pf.options[document.forms[0].slct_pf.options.selectedIndex].value;
	if(pf==0)
		alert("Player plays first.");
	if(pf==1)
	{
		alert("Computer plays first.");
		meFirst=true;
	}
	if(pf=="none")
		alert("Please select who plays first!");
	if(size=="none")
		alert("Please select a Board size!");

	if((size=="other")&&(pf!="none"))
	{
		puts='<form name="form2"><span style="font-family:verdana,arial; font-size:10pt; color:#000000">Enter size (eg 7): </span> <input type="text" name="ip" class="ip"> <input type="button" onClick="resolveMove(document.form2.ip.value)" value="Play!" class="btn"></form>';
		document.getElementById('container').innerHTML=puts;
	}
	if((size!="none")&&(size!="other")&&(pf!="none"))
		resolveMove(size);
}

function resolveMove(size)
{
	genBox(size,'container');
	if(meFirst)
		setTimeout("playFirst('"+size+"')",300);
}