QValidator::State QNickValidator::validate(const QString &input) const
{
    if (input.length() > 20)
    {
        return QValidator::Invalid;
    }
    if (input.length() == 0)
        return QValidator::Intermediate;

    if (!isBegEndChar(input[0])) {
        return QValidator::Invalid;
    }

    bool spaced = false;
    bool punct = false;

    for (int i = 0; i < input.length(); i++) {
        if (input[i] == '\n' || input[i] == '%' || input[i] == '*' || input[i] == '<' || input[i] == ':' || input[i] == '(' || input[i] == ')'
            || input[i] == ';')
            return QValidator::Invalid;
        if (input[i].isPunct()) {
            if (punct == true) {
                //Error: two punctuations are not separated by a letter/number
                return QValidator::Invalid;
            }
            punct = true;
            spaced = false;
        } else if (input[i] == ' ') {
            if (spaced == true) {
                //Error: two spaces are following
                return QValidator::Invalid;
            }
            spaced = true;
        } else if (input[i].isLetterOrNumber()) {
            //we allow another punct & space
            punct = false;
            spaced = false;
        }

        if (input[i].category() >= QChar::Other_Control && input[i].category() <= QChar::Other_NotAssigned) {
            return QValidator::Intermediate;
        }
    }

    //let's check if there is at least a letter/number & no whitespace at the end
    if (input.length() == 1 && input[0].isPunct()) {
        return QValidator::Intermediate;
    }
    if (!isBegEndChar(input[input.length()-1])) {
        return QValidator::Intermediate;
    }

    return QValidator::Acceptable;
}