/*
 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
 * Copyright (C) 2006-2007 Dan Fuhry
 * pwstrength - Password evaluation and strength testing algorithm
 *
 * This program is Free Software; you can redistribute 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 details.
 */

function password_score_len(password)
{
	if ( typeof(password) != "string" )
	{
		return -10;
	}
	var len = password.length;
	var score = len - 7;
	return score;
}

function password_score(password)
{
	if ( typeof(password) != "string" )
	{
		return -10;
	}
	var score = 0;
	var debug = [];
	// length check
	var lenscore = password_score_len(password);
	
	debug.push(''+lenscore+' points for length');
	
	score += lenscore;
		
	var has_upper_lower = false;
	var has_symbols     = false;
	var has_numbers     = false;
	
	// contains uppercase and lowercase
	if ( password.match(/[A-z]+/) && password.toLowerCase() != password )
	{
		score += 1;
		has_upper_lower = true;
		debug.push('1 point for having uppercase and lowercase');
	}
	
	// contains symbols
	if ( password.match(/[^A-z0-9]+/) )
	{
		score += 1;
		has_symbols = true;
		debug.push('1 point for having nonalphanumeric characters (matching /[^A-z0-9]+/)');
	}
	
	// contains numbers
	if ( password.match(/[0-9]+/) )
	{
		score += 1;
		has_numbers = true;
		debug.push('1 point for having numbers');
	}
	
	if ( has_upper_lower && has_symbols && has_numbers && password.length >= 9 )
	{
		// if it has uppercase and lowercase letters, symbols, and numbers, and is of considerable length, add some serious points
		score += 4;
		debug.push('4 points for having uppercase and lowercase, numbers, and nonalphanumeric and being more than 8 characters');
	}
	else if ( has_upper_lower && has_symbols && has_numbers && password.length >= 6 )
	{
		// still give some points for passing complexity check
		score += 2;
		debug.push('2 points for having uppercase and lowercase, numbers, and nonalphanumeric');
	}
	else if(( ( has_upper_lower && has_symbols ) ||
						( has_upper_lower && has_numbers ) ||
						( has_symbols && has_numbers ) ) && password.length >= 6 )
	{
		// if 2 of the three main complexity checks passed, add a point
		score += 1;
		debug.push('1 point for having 2 of 3 complexity checks');
	}
	else if ( ( !has_upper_lower && !has_numbers && has_symbols ) ||
						( !has_upper_lower && !has_symbols && has_numbers ) ||
						( !has_numbers && !has_symbols && has_upper_lower ) )
	{
		score += -2;
		debug.push('-2 points for only meeting 1 complexity check');
	}
	else if ( password.match(/^[0-9]*?([a-z]+)[0-9]?$/) )
	{
		// password is something like magnum1 which will be cracked in seconds
		score += -4;
		debug.push('-4 points for being of the form [number][word][number], which is easily cracked');
	}
	else if ( !has_upper_lower && !has_numbers && !has_symbols )
	{
		// this is if somehow the user inputs a password that doesn't match the rule above, but still doesn't contain upper and lowercase, numbers, or symbols
		debug.push('-3 points for not meeting any complexity checks');
		score += -3;
	}
	
	//
	// Repetition
	// Example: foobar12345 should be deducted points, where f1o2o3b4a5r should be given points
	// None of the positive ones kick in unless the length is at least 8
	//
	
	if ( password.match(/([A-Z][A-Z][A-Z][A-Z]|[a-z][a-z][a-z][a-z])/) )
	{
		debug.push('-2 points for having more than 4 letters of the same case in a row');
		score += -2;
	}
	else if ( password.match(/([A-Z][A-Z][A-Z]|[a-z][a-z][a-z])/) )
	{
		debug.push('-1 points for having more than 3 letters of the same case in a row');
		score += -1;
	}
	else if ( password.match(/[A-z]/) && !password.match(/([A-Z][A-Z][A-Z]|[a-z][a-z][a-z])/) && password.length >= 8 )
	{
		debug.push('1 point for never having more than 2 letters of the same case in a row');
		score += 1;
	}
	
	if ( password.match(/[0-9][0-9][0-9][0-9]/) )
	{
		debug.push('-2 points for having 4 or more numbers in a row');
		score += -2;
	}
	else if ( password.match(/[0-9][0-9][0-9]/) )
	{
		debug.push('-1 points for having 3 or more numbers in a row');
		score += -1;
	}
	else if ( has_numbers && !password.match(/[0-9][0-9][0-9]/) && password.length >= 8 )
	{
		debug.push('1 point for never more than 2 numbers in a row');
		score += -1;
	}
	
	// make passwords like fooooooooooooooooooooooooooooooooooooo totally die by subtracting a point for each character repeated at least 3 times in a row
	var prev_char = '';
	var warn = false;
	var loss = 0;
	for ( var i = 0; i < password.length; i++ )
	{
		var chr = password.substr(i, 1);
		if ( chr == prev_char && warn )
		{
			loss += -1;
		}
		else if ( chr == prev_char && !warn )
		{
			warn = true;
		}
		else if ( chr != prev_char && warn )
		{
			warn = false;
		}
		prev_char = chr;
	}
	if ( loss < 0 )
	{
		debug.push(''+loss+' points for immediate character repetition');
		score += loss;
		// this can bring the score below -10 sometimes
		if ( score < -10 )
		{
			debug.push('Score set to -10 because it went below that floor');
			score = -10;
		}
	}
	
	var debug_txt = "<b>How this score was calculated</b>\nYour score was tallied up based on an extensive algorithm which outputted\nthe following scores based on traits of your password. Above you can see the\ncomposite score; your individual scores based on certain tests are below.\n\nThe scale is open-ended, with a minimum score of -10. 10 is very strong, 4\nis strong, 1 is good and -3 is fair. Below -3 scores \"Weak.\"\n\n";
	for ( var i = 0; i < debug.length; i++ )
	{
		debug_txt += debug[i] + "\n";
	}
	
	// For users that really want to know why their password sucks.
	// Not localized because the feature is really only used for debugging the algorithm.
	if ( document.getElementById('passdebug') )
		document.getElementById('passdebug').innerHTML = debug_txt;
	
	return score;
}

function password_score_draw(score)
{
	if ( !$lang )
	{
		// $lang isn't initted yet, this happens sometimes on the usercp/emailpassword form.
		// Try to init it if we have ENANO_LANG_ID and enano_lang; if not, report an error.
		load_component('l10n');
		if ( typeof(enano_lang) == 'object' && typeof(ENANO_LANG_ID) == 'number' )
		{
			language_onload();
		}
		else
		{      
			return {
				'color' : '#000000',
				'fgcolor' : '#666666',
				'str' : 'Language init failed'
			};
		}
	}
	// some colors are from the Gmail sign-up form
	if ( score >= 10 )
	{
		var color = '#010101';
		var fgcolor = '#666666';
		var str = $lang.get('usercp_pwstrength_score_verystrong', { score: score });
	}
	else if ( score > 3 )
	{
		var color = '#008000';
		var fgcolor = '#004000';
		var str = $lang.get('usercp_pwstrength_score_strong', { score: score });
	}
	else if ( score >= 1 )
	{
		var color = '#6699cc';
		var fgcolor = '#4477aa';
		var str = $lang.get('usercp_pwstrength_score_good', { score: score });
	}
	else if ( score >= -3 )
	{
		var color = '#f5ac00';
		var fgcolor = '#ffcc33';
		var str = $lang.get('usercp_pwstrength_score_fair', { score: score });
	}
	else
	{
		var color = '#aa0033';
		var fgcolor = '#FF6060';
		var str = $lang.get('usercp_pwstrength_score_weak', { score: score });
	}
	var ret = {
		color: color,
		fgcolor: fgcolor,
		str: str
	};
	return ret;
}

function password_score_field(field)
{
	var indicator = false;
	if ( field.nextSibling )
	{
		if ( field.nextSibling.className == 'password-checker' )
		{
			indicator = field.nextSibling;
		}
	}
	if ( !indicator )
	{
		var indicator = document.createElement('span');
		indicator.className = 'password-checker';
		if ( field.nextSibling )
		{
			field.parentNode.insertBefore(indicator, field.nextSibling);
		}
		else
		{
			field.parentNode.appendChild(indicator);
		}
	}
	var score = password_score(field.value);
	var data = password_score_draw(score);
	indicator.style.color = data.color;
	indicator.style.fontWeight = 'bold';
	indicator.innerHTML = ' ' + data.str;
	
	if ( document.getElementById('pwmeter') )
	{
		var div = document.getElementById('pwmeter');
		div.style.width = '250px';
		score += 10;
		if ( score > 25 )
			score = 25;
		div.style.backgroundColor = data.color;
		var width = Math.round( score * (250 / 25) );
		div.innerHTML = '<div style="width: '+width+'px; background-color: '+data.fgcolor+'; height: 8px;"></div>';
	}
}