/*
**    Created by: Jeff Todnem (http://www.todnem.com/)
**    Created on: 2007-08-14
**    Last modified: 2010-05-03
**
**    License Information:
**    -------------------------------------------------------------------------
**    Copyright (C) 2007 Jeff Todnem
**
**    This program is free software; you can redistribute it and/or modify it
**    under the terms of the GNU General Public License as published by the
**    Free Software Foundation; either version 2 of the License, or (at your
**    option) any later version.
**    
**    This program is distributed in the hope that it will be useful, but
**    WITHOUT ANY WARRANTY; without even the implied warranty of
**    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
**    General Public License for more details.
**    
**    You should have received a copy of the GNU General Public License along
**    with this program; if not, write to the Free Software Foundation, Inc.,
**    59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
**    
*/

function $() {
	var arrElms = [];
	for (var i=0; i < arguments.length; i++) {
		var elm = arguments[i];
		if (typeof(elm == "string")) { elm = document.getElementById(elm); }
		if (arguments.length == 1) { return elm; }
		arrElms.push(elm);
	}
	return arrElms;
}

String.prototype.strReverse = function() {
	var newstring = "";
	for (var s=0; s < this.length; s++) {
		newstring = this.charAt(s) + newstring;
	}
	return newstring;
};

function chkPass(pwdID, containerID) {
    var objPwd = $(pwdID);
    var objContainer = $(containerID);
    var pwd = "";
    if(objPwd != null)
        pwd = objPwd.value;
           
	var oScorebar = $("scorebar");
	var oScore = $("score");
	var oComplexity = $("complexity");
	// Simultaneous variable declaration and value assignment aren't supported in IE apparently
	// so I'm forced to assign the same value individually per var to support a crappy browser *sigh* 
	var nScore=0, nLength=0, nAlphaUC=0, nAlphaLC=0, nNumber=0, nSymbol=0, nMidChar=0, nRequirements=0, nAlphasOnly=0, nNumbersOnly=0, nUnqChar=0, nRepChar=0, nRepInc=0, nConsecAlphaUC=0, nConsecAlphaLC=0, nConsecNumber=0, nConsecSymbol=0, nConsecCharType=0, nSeqAlpha=0, nSeqNumber=0, nSeqSymbol=0, nSeqChar=0, nReqChar=0, nMultConsecCharType=0;
	var nMultRepChar=1, nMultConsecSymbol=1;
	var nMultMidChar=2, nMultRequirements=2, nMultConsecAlphaUC=2, nMultConsecAlphaLC=2, nMultConsecNumber=2;
	var nReqCharType=3, nMultAlphaUC=3, nMultAlphaLC=3, nMultSeqAlpha=3, nMultSeqNumber=3, nMultSeqSymbol=3;
	var nMultLength=4, nMultNumber=4;
	var nMultSymbol=6;
	var nTmpAlphaUC="", nTmpAlphaLC="", nTmpNumber="", nTmpSymbol="";
	var sAlphas = "abcdefghijklmnopqrstuvwxyz";
	var sNumerics = "01234567890";
	var sSymbols = ")!@#$%^&*()";
	var sComplexity = "Quá ngắn";
	var nMinPwdLen = 6;
    
    if (pwd != "") {
		nScore = parseInt(pwd.length * nMultLength);
		nLength = pwd.length;
		var arrPwd = pwd.replace(/\s+/g,"").split(/\s*/);
		var arrPwdLen = arrPwd.length;
		
		/* Loop through password to check for Symbol, Numeric, Lowercase and Uppercase pattern matches */
		for (var a=0; a < arrPwdLen; a++) {
			if (arrPwd[a].match(/[A-Z]/g)) {
				if (nTmpAlphaUC !== "") { if ((nTmpAlphaUC + 1) == a) { nConsecAlphaUC++; nConsecCharType++; } }
				nTmpAlphaUC = a;
				nAlphaUC++;
			}
			else if (arrPwd[a].match(/[a-z]/g)) { 
				if (nTmpAlphaLC !== "") { if ((nTmpAlphaLC + 1) == a) { nConsecAlphaLC++; nConsecCharType++; } }
				nTmpAlphaLC = a;
				nAlphaLC++;
			}
			else if (arrPwd[a].match(/[0-9]/g)) { 
				if (a > 0 && a < (arrPwdLen - 1)) { nMidChar++; }
				if (nTmpNumber !== "") { if ((nTmpNumber + 1) == a) { nConsecNumber++; nConsecCharType++; } }
				nTmpNumber = a;
				nNumber++;
			}
			else if (arrPwd[a].match(/[^a-zA-Z0-9_]/g)) { 
				if (a > 0 && a < (arrPwdLen - 1)) { nMidChar++; }
				if (nTmpSymbol !== "") { if ((nTmpSymbol + 1) == a) { nConsecSymbol++; nConsecCharType++; } }
				nTmpSymbol = a;
				nSymbol++;
			}
			/* Internal loop through password to check for repeat characters */
			var bCharExists = false;
			for (var b=0; b < arrPwdLen; b++) {
				if (arrPwd[a] == arrPwd[b] && a != b) { /* repeat character exists */
					bCharExists = true;
					/* 
					Calculate icrement deduction based on proximity to identical characters
					Deduction is incremented each time a new match is discovered
					Deduction amount is based on total password length divided by the
					difference of distance between currently selected match
					*/
					nRepInc += Math.abs(arrPwdLen/(b-a));
				}
			}
			if (bCharExists) { 
				nRepChar++; 
				nUnqChar = arrPwdLen-nRepChar;
				nRepInc = (nUnqChar) ? Math.ceil(nRepInc/nUnqChar) : Math.ceil(nRepInc); 
			}
		}
		
		/* Check for sequential alpha string patterns (forward and reverse) */
		for (var s=0; s < 23; s++) {
			var sFwd = sAlphas.substring(s,parseInt(s+3));
			var sRev = sFwd.strReverse();
			if (pwd.toLowerCase().indexOf(sFwd) != -1 || pwd.toLowerCase().indexOf(sRev) != -1) { nSeqAlpha++; nSeqChar++;}
		}
		
		/* Check for sequential numeric string patterns (forward and reverse) */
		for (var s=0; s < 8; s++) {
			var sFwd = sNumerics.substring(s,parseInt(s+3));
			var sRev = sFwd.strReverse();
			if (pwd.toLowerCase().indexOf(sFwd) != -1 || pwd.toLowerCase().indexOf(sRev) != -1) { nSeqNumber++; nSeqChar++;}
		}
		
		/* Check for sequential symbol string patterns (forward and reverse) */
		for (var s=0; s < 8; s++) {
			var sFwd = sSymbols.substring(s,parseInt(s+3));
			var sRev = sFwd.strReverse();
			if (pwd.toLowerCase().indexOf(sFwd) != -1 || pwd.toLowerCase().indexOf(sRev) != -1) { nSeqSymbol++; nSeqChar++;}
		}
		
	/* Modify overall score value based on usage vs requirements */

		/* General point assignment */
		
		if (nAlphaUC > 0 && nAlphaUC < nLength) {	
			nScore = parseInt(nScore + ((nLength - nAlphaUC) * 2));
		}
		if (nAlphaLC > 0 && nAlphaLC < nLength) {	
			nScore = parseInt(nScore + ((nLength - nAlphaLC) * 2)); 
		}
		if (nNumber > 0 && nNumber < nLength) {	
			nScore = parseInt(nScore + (nNumber * nMultNumber));
		}
		if (nSymbol > 0) {	
			nScore = parseInt(nScore + (nSymbol * nMultSymbol));
		}
		if (nMidChar > 0) {	
			nScore = parseInt(nScore + (nMidChar * nMultMidChar));
		}
		
		/* Point deductions for poor practices */
		if ((nAlphaLC > 0 || nAlphaUC > 0) && nSymbol === 0 && nNumber === 0) {  // Only Letters
			nScore = parseInt(nScore - nLength);
			nAlphasOnly = nLength;
		}
		if (nAlphaLC === 0 && nAlphaUC === 0 && nSymbol === 0 && nNumber > 0) {  // Only Numbers
			nScore = parseInt(nScore - nLength); 
			nNumbersOnly = nLength;
		}
		if (nRepChar > 0) {  // Same character exists more than once
			nScore = parseInt(nScore - nRepInc);
		}
		if (nConsecAlphaUC > 0) {  // Consecutive Uppercase Letters exist
			nScore = parseInt(nScore - (nConsecAlphaUC * nMultConsecAlphaUC)); 
		}
		if (nConsecAlphaLC > 0) {  // Consecutive Lowercase Letters exist
			nScore = parseInt(nScore - (nConsecAlphaLC * nMultConsecAlphaLC)); 
		}
		if (nConsecNumber > 0) {  // Consecutive Numbers exist
			nScore = parseInt(nScore - (nConsecNumber * nMultConsecNumber));  
		}
		if (nSeqAlpha > 0) {  // Sequential alpha strings exist (3 characters or more)
			nScore = parseInt(nScore - (nSeqAlpha * nMultSeqAlpha)); 
		}
		if (nSeqNumber > 0) {  // Sequential numeric strings exist (3 characters or more)
			nScore = parseInt(nScore - (nSeqNumber * nMultSeqNumber)); 
		}
		if (nSeqSymbol > 0) {  // Sequential symbol strings exist (3 characters or more)
		}
		
		/* Determine if mandatory requirements have been met and set image indicators accordingly */
		var arrChars = [nLength,nAlphaUC,nAlphaLC,nNumber,nSymbol];
		var arrCharsIds = ["nLength","nAlphaUC","nAlphaLC","nNumber","nSymbol"];
		var arrCharsLen = arrChars.length;
		for (var c=0; c < arrCharsLen; c++) {
			if (arrCharsIds[c] == "nLength") { var minVal = parseInt(nMinPwdLen - 1); } else { var minVal = 0; }
			if (arrChars[c] == parseInt(minVal + 1)) { nReqChar++;}
			else if (arrChars[c] > parseInt(minVal + 1)) { nReqChar++;}
		}
		nRequirements = nReqChar;
		if (pwd.length >= nMinPwdLen) { var nMinReqChars = 3; } else { var nMinReqChars = 4; }
		if (nRequirements > nMinReqChars) {  // One or more required characters exist
			nScore = parseInt(nScore + (nRequirements * 2)); 
		}
		
		/* Determine complexity based on overall score */
		if (nScore > 100) { nScore = 100; } else if (nScore < 0) { nScore = 0; }
		if (nScore >= 0 && nScore < 20) { sComplexity = "Rất yếu"; }
		else if (nScore >= 20 && nScore < 40) { sComplexity = "Yếu"; }
		else if (nScore >= 40 && nScore < 60) { sComplexity = "Trung bình"; }
		else if (nScore >= 60 && nScore < 80) { sComplexity = "Mạnh"; }
		else if (nScore >= 80 && nScore <= 100) { sComplexity = "Rất mạnh"; }
		/* Display updated score criteria to client */
		oScorebar.style.backgroundPosition = "-" + parseInt(nScore * 4) + "px";
		oScore.innerHTML = nScore + "%";
		oComplexity.innerHTML = sComplexity;
		objContainer.style.display = "";
	}
	else 
	{
		/* Display default score criteria to client */
		objContainer.style.display = "none";
		oScore.innerHTML = nScore + "%";
		oComplexity.innerHTML = sComplexity;
	}
}