Generate password regexp for validating purpose

generatePasswordRegex.js

/**
 * Generate password regex
 * @method generatePasswordRegex
 * @param {Number} min Minimum length of password
 * @param {Number} max Maximum length of password
 * @param {String} specialCharacter List of special characters
 * @param {Number} specialLength Number of required special character in password
 * @param {Number} uppercaseLength Number of required uppercase character in password
 * @param {Number} numberLength Number of digit character in password * 
 */

function generatePasswordRegex(options) {
    var regexString = '(?=(?:.*[a-z]){1})';

        if (options.uppercaseLength > 0) {
            regexString += '(?=(?:.*[A-Z]){' + options.uppercaseLength + '})';
        }

        if (options.numberLength > 0) {
            regexString += '(?=(?:.*\\d){' + options.numberLength + '})';
        }

        if (options.specialLength > 0) {
            regexString += '(?=(?:.*[' + options.specialCharacter + ']){' + options.numberLength + '})';
        }

        regexString += '.{' + options.min + ',' + options.max + '}';

        return new RegExp('^' + regexString + '$');
}

var regex = generatePasswordRegex({
    min: 8,
    max: 32,
    specialCharacter: '!@#$%^&*-',
    specialLength: 1,
    uppercaseLength: 1,
    numberLength: 1
});

console.log('Passw0rd@'); // true
console.log('@Passw0rd'); // true