// form_validation v. 2.0
//  ----------------------------
// | Euroweb Internet GmbH     |
//  ----------------------------
//        Last changed:        15. 11. 2006


function validateForm(formular) {
        var error = 0;
        var currentLabel = '';
        var currentField = '';
        var klasse = '';
        var newClass = '';

        // Inspect all of the document's labels ...
        for (var i = 0; i < document.getElementsByTagName("label").length; i++) {
                currentLabel = document.getElementsByTagName("label")[i];
                if (currentLabel.htmlFor) {
                        currentField = document.getElementById(currentLabel.htmlFor);
                }
                klasse = currentLabel.className;
                newClass = currentLabel.className.replace(/ error/, '');

                // Check if the current label belongs to the form we want to validate
                if (currentLabel.form == formular && currentField) {

                        // ...  and if it is required at all, or has to be a number, or an e-mail address.

                                // Rueckruf exists: Mark phone number field as required
                                if (currentField.name == 'Rueckruf') {
                                        if (currentField.checked == true) {
                                                document.getElementById('label-telefon').className += ' required rueckruf';
                                        } else {
                                                var newTelClass = document.getElementById('label-telefon').className.replace(/ required rueckruf/, '');
                                                document.getElementById('label-telefon').className = newTelClass;
                                        }
                                }

                                // required field (but neither numeric nor an e-mail)
                                if (klasse.match(/required/)) {
                                        if (currentField.value == '') {
                                                currentLabel.className = newClass;
                                                currentLabel.className += ' error';
                                                error = 1;
                                        } else {
                                                currentLabel.className = newClass;
                                        }
                                }

                                // numeric field
                                if (klasse.match(/number/)) {
                                        var numeric = isNumber(currentField);
                                        if (!numeric && !klasse.match(/required/) && currentField.value != '') {
                                                currentLabel.className = newClass;
                                                currentLabel.className += ' error';
                                                error = 1;
                                        } else {
                                                currentLabel.className = newClass;
                                        }
                                        if (!numeric && klasse.match(/required/)) {
                                                currentLabel.className = newClass;
                                                currentLabel.className += ' error';
                                                error = 1;
                                        } else {
                                                if (error == 0) {
                                                        currentLabel.className = newClass;
                                                }
                                        }
                                }

                                // e-mail address
                                if (klasse.match(/mail/)) {
                                        var valid = isMailValid(currentField);
                                        if (!valid && currentField.value != '') {
                                                currentLabel.className = newClass;
                                                currentLabel.className += ' error';
                                                error = 1;
                                        } else {
                                                currentLabel.className = newClass;
                                        }
                                        if (!valid && klasse.match(/required/)) {
                                                currentLabel.className = newClass;
                                                currentLabel.className += ' error';
                                                error = 1;
                                        } else {
                                                if (error == 0) {
                                                        currentLabel.className = newClass;
                                                }
                                        }
                                }


                }

        } // end for


        // Return TRUE and proceed sending the form if no errors occured.
        // Return FALSE in case of errors and display the error message,
        // then focus on the ID of the element containing the error message.

        // (The window.location.href call comes in handy if the page containing
        //        the form is as high as serveral screens,
        //  but can be safely removed without preventing the script to function properly).
        if (error === 0) {
                return true;
        } else {
                document.getElementById("fehlermeldung").style.display = 'block';
                window.location.href = "#fehlermeldung";
                return false;
        }

}



// Additional functions for numeric and e-mail validation
function isNumber(field) {
        var returnvar = (isNaN(parseInt(field.value)) == true) ? false : true;
        return returnvar;
}

function isMailValid(field) {
        var returnvar = (field.value.match(/^[\w\.\-]+@([\w\-]+\.)+[a-zA-Z]+$/)) ? true : false;
        return returnvar;
}