/*

 * 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";

  }

  if ( window.console )

    window.console.info(debug_txt);

  else if ( document.getElementById('passdebug') )

    document.getElementById('passdebug').innerHTML = debug_txt;

  return score;

}

function password_score_draw(score)

{

  // some colors are from the Gmail sign-up form

  if ( score >= 10 )

  {

    var color = '#000000';

    var fgcolor = '#666666';

    var str = 'Very strong (score: '+score+')';

  }

  else if ( score > 3 )

  {

    var color = '#008000';

    var fgcolor = '#004000';

    var str = 'Strong (score: '+score+')';

  }

  else if ( score >= 1 )

  {

    var color = '#6699cc';

    var fgcolor = '#4477aa';

    var str = 'Good (score: '+score+')';

  }

  else if ( score >= -3 )

  {

    var color = '#f5ac00';

    var fgcolor = '#ffcc33';

    var str = 'Fair (score: '+score+')';

  }

  else

  {

    var color = '#aa0033';

    var fgcolor = '#FF6060';

    var str = 'Weak (score: '+score+')';

  }

  return {

    color: color,

    fgcolor: fgcolor,

    str: str

  };

}

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>';

  }

}