var aPasswordStrength = new Array();
aPasswordStrength[0] = new Array("Low", "PasswordTooShort");
aPasswordStrength[1] = new Array("Weak", "PasswordWeak");
aPasswordStrength[2] = new Array("Medium", "PasswordMedium");
aPasswordStrength[3] = new Array("Strong", "PasswordStrong");


function getPasswordStrength(sPassword, iPasswordLength) {

    var iScore = 0;

    //if password longer than 8 give 1 point
    if (sPassword.length >= iPasswordLength) {
        iScore += 1;
    }    
    else {
        return 0;
    }
    // Yiran 2011-01-20 medium strength changes, true if any two of groups matched.      
    //if password has both lower and uppercase characters and at least on number give 1 point
    if ((sPassword.match(/[a-z]/) && sPassword.match(/[A-Z]/)) || (sPassword.match(/[a-z]/) && sPassword.match(/\d+/)) || (sPassword.match(/[a-z]/) && sPassword.match(/\W/)) || (sPassword.match(/[A-Z]/) && sPassword.match(/\d+/)) || (sPassword.match(/[A-Z]/) && sPassword.match(/\W/)) || (sPassword.match(/\d+/) && sPassword.match(/\W/))) {        
        iScore += 1;
    }
    

    //if password has at least one special caracther give 1 point
    if (sPassword.match(/[a-z]/) && sPassword.match(/[A-Z]/) && sPassword.match(/\d+/) && sPassword.match(/\W/)) { 
        iScore += 1; 
    }
            
    return iScore;
}

function setPasswordStrengthGUI(sTextFieldName, sPosBarFieldName, sNegBarFieldName, sPassword, iPasswordLength) {

    var iStrength = getPasswordStrength(sPassword, iPasswordLength)

    if (sPassword.length > 0) {
        document.getElementById(sTextFieldName).innerHTML = aPasswordStrength[iStrength][0];
    }
    else {
        document.getElementById(sTextFieldName).innerHTML = "";
    }

    document.getElementById(sTextFieldName).removeAttribute("class", 0);
    document.getElementById(sPosBarFieldName).removeAttribute("class", 0);
    document.getElementById(sNegBarFieldName).removeAttribute("class", 0);
    
    document.getElementById(sTextFieldName).setAttribute("class", aPasswordStrength[iStrength][1]);
    document.getElementById(sPosBarFieldName).setAttribute("class", aPasswordStrength[iStrength][1] + "Pos");
    document.getElementById(sNegBarFieldName).setAttribute("class", aPasswordStrength[iStrength][1] + "Neg");

    document.getElementById(sTextFieldName).className = aPasswordStrength[iStrength][1];
    document.getElementById(sPosBarFieldName).className = aPasswordStrength[iStrength][1] + "Pos";
    document.getElementById(sNegBarFieldName).className = aPasswordStrength[iStrength][1] + "Neg";
}