weekly release 1.9.13+

[moodle.git] / lib / formslib.php

<?php // $Id$
/**
 * formslib.php - library of classes for creating forms in Moodle, based on PEAR QuickForms.
 *
 * To use formslib then you will want to create a new file purpose_form.php eg. edit_form.php
 * and you want to name your class something like {modulename}_{purpose}_form. Your class will
 * extend moodleform overriding abstract classes definition and optionally defintion_after_data
 * and validation.
 *
 * See examples of use of this library in course/edit.php and course/edit_form.php
 *
 * A few notes :
 *      form defintion is used for both printing of form and processing and should be the same
 *              for both or you may lose some submitted data which won't be let through.
 *      you should be using setType for every form element except select, radio or checkbox
 *              elements, these elements clean themselves.
 *
 *
 * @author  Jamie Pratt
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 */

if (!defined('MOODLE_INTERNAL')) {
    die('Direct access to this script is forbidden.');    ///  It must be included from a Moodle page
}


//setup.php icludes our hacked pear libs first
require_once 'HTML/QuickForm.php';
require_once 'HTML/QuickForm/DHTMLRulesTableless.php';
require_once 'HTML/QuickForm/Renderer/Tableless.php';

require_once $CFG->libdir.'/uploadlib.php';

/**
 * Callback called when PEAR throws an error
 *
 * @param PEAR_Error $error
 */
function pear_handle_error($error){
    echo '<strong>'.$error->GetMessage().'</strong> '.$error->getUserInfo();
    echo '<br /> <strong>Backtrace </strong>:';
    print_object($error->backtrace);
}

if ($CFG->debug >= DEBUG_ALL){
    PEAR::setErrorHandling(PEAR_ERROR_CALLBACK, 'pear_handle_error');
}


/**
 * Moodle specific wrapper that separates quickforms syntax from moodle code. You won't directly
 * use this class you should write a class definition which extends this class or a more specific
 * subclass such a moodleform_mod for each form you want to display and/or process with formslib.
 *
 * You will write your own definition() method which performs the form set up.
 */
class moodleform {
    var $_formname;       // form name
    /**
     * quickform object definition
     *
     * @var MoodleQuickForm
     */
    var $_form;
    /**
     * globals workaround
     *
     * @var array
     */
    var $_customdata;
    /**
     * file upload manager
     *
     * @var upload_manager
     */
    var $_upload_manager; //
    /**
     * definition_after_data executed flag
     * @var definition_finalized
     */
    var $_definition_finalized = false;

    /**
     * The constructor function calls the abstract function definition() and it will then
     * process and clean and attempt to validate incoming data.
     *
     * It will call your custom validate method to validate data and will also check any rules
     * you have specified in definition using addRule
     *
     * The name of the form (id attribute of the form) is automatically generated depending on
     * the name you gave the class extending moodleform. You should call your class something
     * like
     *
     * @param mixed $action the action attribute for the form. If empty defaults to auto detect the
     *                  current url. If a moodle_url object then outputs params as hidden variables.
     * @param array $customdata if your form defintion method needs access to data such as $course
     *               $cm, etc. to construct the form definition then pass it in this array. You can
     *               use globals for somethings.
     * @param string $method if you set this to anything other than 'post' then _GET and _POST will
     *               be merged and used as incoming data to the form.
     * @param string $target target frame for form submission. You will rarely use this. Don't use
     *                  it if you don't need to as the target attribute is deprecated in xhtml
     *                  strict.
     * @param mixed $attributes you can pass a string of html attributes here or an array.
     * @return moodleform
     */
    function moodleform($action=null, $customdata=null, $method='post', $target='', $attributes=null, $editable=true) {
        if (empty($action)){
            $action = strip_querystring(qualified_me());
        }

        $this->_formname = get_class($this); // '_form' suffix kept in order to prevent collisions of form id and other element
        $this->_customdata = $customdata;
        $this->_form =& new MoodleQuickForm($this->_formname, $method, $action, $target, $attributes);
        if (!$editable){
            $this->_form->hardFreeze();
        }
        $this->set_upload_manager(new upload_manager());

        $this->definition();

        $this->_form->addElement('hidden', 'sesskey', null); // automatic sesskey protection
        $this->_form->setType('sesskey', PARAM_RAW);
        $this->_form->setDefault('sesskey', sesskey());
        $this->_form->addElement('hidden', '_qf__'.$this->_formname, null);   // form submission marker
        $this->_form->setType('_qf__'.$this->_formname, PARAM_RAW);
        $this->_form->setDefault('_qf__'.$this->_formname, 1);
        $this->_form->_setDefaultRuleMessages();

        // we have to know all input types before processing submission ;-)
        $this->_process_submission($method);
    }

    /**
     * To autofocus on first form element or first element with error.
     *
     * @param string $name if this is set then the focus is forced to a field with this name
     *
     * @return string  javascript to select form element with first error or
     *                  first element if no errors. Use this as a parameter
     *                  when calling print_header
     */
    function focus($name=NULL) {
        $form =& $this->_form;
        $elkeys = array_keys($form->_elementIndex);
        $error = false;
        if (isset($form->_errors) &&  0 != count($form->_errors)){
            $errorkeys = array_keys($form->_errors);
            $elkeys = array_intersect($elkeys, $errorkeys);
            $error = true;
        }

        if ($error or empty($name)) {
            $names = array();
            while (empty($names) and !empty($elkeys)) {
                $el = array_shift($elkeys);
                $names = $form->_getElNamesRecursive($el);
            }
            if (!empty($names)) {
                $name = array_shift($names);
            }
        }

        $focus = '';
        if (!empty($name)) {
            $focus = 'forms[\''.$form->getAttribute('id').'\'].elements[\''.$name.'\']';
        }

        return $focus;
     }

    /**
     * Internal method. Alters submitted data to be suitable for quickforms processing.
     * Must be called when the form is fully set up.
     */
    function _process_submission($method) {
        $submission = array();
        if ($method == 'post') {
            if (!empty($_POST)) {
                $submission = $_POST;
            }
        } else {
            $submission = array_merge_recursive($_GET, $_POST); // emulate handling of parameters in xxxx_param()
        }

        // following trick is needed to enable proper sesskey checks when using GET forms
        // the _qf__.$this->_formname serves as a marker that form was actually submitted
        if (array_key_exists('_qf__'.$this->_formname, $submission) and $submission['_qf__'.$this->_formname] == 1) {
            if (!confirm_sesskey()) {
                print_error('invalidsesskey');
            }
            $files = $_FILES;
        } else {
            $submission = array();
            $files = array();
        }

        $this->_form->updateSubmission($submission, $files);
    }

    /**
     * Internal method. Validates all uploaded files.
     */
    function _validate_files(&$files) {
        $files = array();

        if (empty($_FILES)) {
            // we do not need to do any checks because no files were submitted
            // note: server side rules do not work for files - use custom verification in validate() instead
            return true;
        }
        $errors = array();
        $mform =& $this->_form;

        // check the files
        $status = $this->_upload_manager->preprocess_files();

        // now check that we really want each file
        foreach ($_FILES as $elname=>$file) {
            if ($mform->elementExists($elname) and $mform->getElementType($elname)=='file') {
                $required = $mform->isElementRequired($elname);
                if (!empty($this->_upload_manager->files[$elname]['uploadlog']) and empty($this->_upload_manager->files[$elname]['clear'])) {
                    if (!$required and $file['error'] == UPLOAD_ERR_NO_FILE) {
                        // file not uploaded and not required - ignore it
                        continue;
                    }
                    $errors[$elname] = $this->_upload_manager->files[$elname]['uploadlog'];

                } else if (!empty($this->_upload_manager->files[$elname]['clear'])) {
                    $files[$elname] = $this->_upload_manager->files[$elname]['tmp_name'];
                }
            } else {
                error('Incorrect upload attempt!');
            }
        }

        // return errors if found
        if ($status and 0 == count($errors)){
            return true;

        } else {
            $files = array();
            return $errors;
        }
    }

    /**
     * Load in existing data as form defaults. Usually new entry defaults are stored directly in
     * form definition (new entry form); this function is used to load in data where values
     * already exist and data is being edited (edit entry form).
     *
     * @param mixed $default_values object or array of default values
     * @param bool $slased true if magic quotes applied to data values
     */
    function set_data($default_values, $slashed=false) {
        if (is_object($default_values)) {
            $default_values = (array)$default_values;
        }
        $filter = $slashed ? 'stripslashes' : NULL;
        $this->_form->setDefaults($default_values, $filter);
    }

    /**
     * Set custom upload manager.
     * Must be used BEFORE creating of file element!
     *
     * @param object $um - custom upload manager
     */
    function set_upload_manager($um=false) {
        if ($um === false) {
            $um = new upload_manager();
        }
        $this->_upload_manager = $um;

        $this->_form->setMaxFileSize($um->config->maxbytes);
    }

    /**
     * Check that form was submitted. Does not check validity of submitted data.
     *
     * @return bool true if form properly submitted
     */
    function is_submitted() {
        return $this->_form->isSubmitted();
    }

    function no_submit_button_pressed(){
        static $nosubmit = null; // one check is enough
        if (!is_null($nosubmit)){
            return $nosubmit;
        }
        $mform =& $this->_form;
        $nosubmit = false;
        if (!$this->is_submitted()){
            return false;
        }
        foreach ($mform->_noSubmitButtons as $nosubmitbutton){
            if (optional_param($nosubmitbutton, 0, PARAM_RAW)){
                $nosubmit = true;
                break;
            }
        }
        return $nosubmit;
    }


    /**
     * Check that form data is valid.
     * You should almost always use this, rather than {@see validate_defined_fields}
     *
     * @return bool true if form data valid
     */
    function is_validated() {
        //finalize the form definition before any processing
        if (!$this->_definition_finalized) {
            $this->_definition_finalized = true;
            $this->definition_after_data();
        }
        return $this->validate_defined_fields();
    }

    /**
     * Validate the form.
     *
     * You almost always want to call {@see is_validated} instead of this
     * because it calls {@see definition_after_data} first, before validating the form,
     * which is what you want in 99% of cases.
     *
     * This is provided as a separate function for those special cases where
     * you want the form validated before definition_after_data is called
     * for example, to selectively add new elements depending on a no_submit_button press,
     * but only when the form is valid when the no_submit_button is pressed,
     *
     * @param boolean $validateonnosubmit optional, defaults to false.  The default behaviour
     *                is NOT to validate the form when a no submit button has been pressed.
     *                pass true here to override this behaviour
     *
     * @return bool true if form data valid
     */
    function validate_defined_fields($validateonnosubmit=false) {
        static $validated = null; // one validation is enough
        $mform =& $this->_form;

        if ($this->no_submit_button_pressed() && empty($validateonnosubmit)){
            return false;
        } elseif ($validated === null) {
            $internal_val = $mform->validate();

            $files = array();
            $file_val = $this->_validate_files($files);
            if ($file_val !== true) {
                if (!empty($file_val)) {
                    foreach ($file_val as $element=>$msg) {
                        $mform->setElementError($element, $msg);
                    }
                }
                $file_val = false;
            }

            $data = $mform->exportValues(null, true);
            $moodle_val = $this->validation($data, $files);
            if ((is_array($moodle_val) && count($moodle_val)!==0)) {
                // non-empty array means errors
                foreach ($moodle_val as $element=>$msg) {
                    $mform->setElementError($element, $msg);
                }
                $moodle_val = false;

            } else {
                // anything else means validation ok
                $moodle_val = true;
            }

            $validated = ($internal_val and $moodle_val and $file_val);
        }
        return $validated;
    }

    /**
     * Return true if a cancel button has been pressed resulting in the form being submitted.
     *
     * @return boolean true if a cancel button has been pressed
     */
    function is_cancelled(){
        $mform =& $this->_form;
        if ($mform->isSubmitted()){
            foreach ($mform->_cancelButtons as $cancelbutton){
                if (optional_param($cancelbutton, 0, PARAM_RAW)){
                    return true;
                }
            }
        }
        return false;
    }

    /**
     * Return submitted data if properly submitted or returns NULL if validation fails or
     * if there is no submitted data.
     *
     * @param bool $slashed true means return data with addslashes applied
     * @return object submitted data; NULL if not valid or not submitted
     */
    function get_data($slashed=true) {
        $mform =& $this->_form;

        if ($this->is_submitted() and $this->is_validated()) {
            $data = $mform->exportValues(null, $slashed);
            unset($data['sesskey']); // we do not need to return sesskey
            unset($data['_qf__'.$this->_formname]);   // we do not need the submission marker too
            if (empty($data)) {
                return NULL;
            } else {
                return (object)$data;
            }
        } else {
            return NULL;
        }
    }

    /**
     * Return submitted data without validation or NULL if there is no submitted data.
     *
     * @param bool $slashed true means return data with addslashes applied
     * @return object submitted data; NULL if not submitted
     */
    function get_submitted_data($slashed=true) {
        $mform =& $this->_form;

        if ($this->is_submitted()) {
            $data = $mform->exportValues(null, $slashed);
            unset($data['sesskey']); // we do not need to return sesskey
            unset($data['_qf__'.$this->_formname]);   // we do not need the submission marker too
            if (empty($data)) {
                return NULL;
            } else {
                return (object)$data;
            }
        } else {
            return NULL;
        }
    }

    /**
     * Save verified uploaded files into directory. Upload process can be customised from definition()
     * method by creating instance of upload manager and storing it in $this->_upload_form
     *
     * @param string $destination where to store uploaded files
     * @return bool success
     */
    function save_files($destination) {
        if ($this->is_submitted() and $this->is_validated()) {
            return $this->_upload_manager->save_files($destination);
        }
        return false;
    }

    /**
     * If we're only handling one file (if inputname was given in the constructor)
     * this will return the (possibly changed) filename of the file.
     * @return mixed false in case of failure, string if ok
     */
    function get_new_filename() {
        return $this->_upload_manager->get_new_filename();
    }

    /**
     * Get content of uploaded file.
     * @param $element name of file upload element
     * @return mixed false in case of failure, string if ok
     */
    function get_file_content($elname) {
        if (!$this->is_submitted() or !$this->is_validated()) {
            return false;
        }

        if (!$this->_form->elementExists($elname)) {
            return false;
        }

        if (empty($this->_upload_manager->files[$elname]['clear'])) {
            return false;
        }

        if (empty($this->_upload_manager->files[$elname]['tmp_name'])) {
            return false;
        }

        $data = "";
        $file = @fopen($this->_upload_manager->files[$elname]['tmp_name'], "rb");
        if ($file) {
            while (!feof($file)) {
                $data .= fread($file, 1024); // TODO: do we really have to do this?
            }
            fclose($file);
            return $data;
        } else {
            return false;
        }
    }

    /**
     * Print html form.
     */
    function display() {
        //finalize the form definition if not yet done
        if (!$this->_definition_finalized) {
            $this->_definition_finalized = true;
            $this->definition_after_data();
        }
        $this->_form->display();
    }

    /**
     * Abstract method - always override!
     *
     * If you need special handling of uploaded files, create instance of $this->_upload_manager here.
     */
    function definition() {
        error('Abstract form_definition() method in class '.get_class($this).' must be overriden, please fix the code.');
    }

    /**
     * Dummy stub method - override if you need to setup the form depending on current
     * values. This method is called after definition(), data submission and set_data().
     * All form setup that is dependent on form values should go in here.
     */
    function definition_after_data(){
    }

    /**
     * Dummy stub method - override if you needed to perform some extra validation.
     * If there are errors return array of errors ("fieldname"=>"error message"),
     * otherwise true if ok.
     *
     * Server side rules do not work for uploaded files, implement serverside rules here if needed.
     *
     * @param array $data array of ("fieldname"=>value) of submitted data
     * @param array $files array of uploaded files "element_name"=>tmp_file_path
     * @return array of "element_name"=>"error_description" if there are errors,
     *               or an empty array if everything is OK (true allowed for backwards compatibility too).
     */
    function validation($data, $files) {
        return array();
    }

    /**
     * Method to add a repeating group of elements to a form.
     *
     * @param array $elementobjs Array of elements or groups of elements that are to be repeated
     * @param integer $repeats no of times to repeat elements initially
     * @param array $options Array of options to apply to elements. Array keys are element names.
     *                      This is an array of arrays. The second sets of keys are the option types
     *                      for the elements :
     *                          'default' - default value is value
     *                          'type' - PARAM_* constant is value
     *                          'helpbutton' - helpbutton params array is value
     *                          'disabledif' - last three moodleform::disabledIf()
     *                                           params are value as an array
     * @param string $repeathiddenname name for hidden element storing no of repeats in this form
     * @param string $addfieldsname name for button to add more fields
     * @param int $addfieldsno how many fields to add at a time
     * @param string $addstring name of button, {no} is replaced by no of blanks that will be added.
     * @param boolean $addbuttoninside if true, don't call closeHeaderBefore($addfieldsname). Default false.
     * @return int no of repeats of element in this page
     */
    function repeat_elements($elementobjs, $repeats, $options, $repeathiddenname,
            $addfieldsname, $addfieldsno=5, $addstring=null, $addbuttoninside=false){
        if ($addstring===null){
            $addstring = get_string('addfields', 'form', $addfieldsno);
        } else {
            $addstring = str_ireplace('{no}', $addfieldsno, $addstring);
        }
        $repeats = optional_param($repeathiddenname, $repeats, PARAM_INT);
        $addfields = optional_param($addfieldsname, '', PARAM_TEXT);
        if (!empty($addfields)){
            $repeats += $addfieldsno;
        }
        $mform =& $this->_form;
        $mform->registerNoSubmitButton($addfieldsname);
        $mform->addElement('hidden', $repeathiddenname, $repeats);
        $mform->setType($repeathiddenname, PARAM_INT);
        //value not to be overridden by submitted value
        $mform->setConstants(array($repeathiddenname=>$repeats));
        $namecloned = array();
        for ($i = 0; $i < $repeats; $i++) {
            foreach ($elementobjs as $elementobj){
                $elementclone = fullclone($elementobj);
                $name = $elementclone->getName();
                $namecloned[] = $name;
                if (!empty($name)) {
                    $elementclone->setName($name."[$i]");
                }
                if (is_a($elementclone, 'HTML_QuickForm_header')) {
                    $value = $elementclone->_text;
                    $elementclone->setValue(str_replace('{no}', ($i+1), $value));

                } else {
                    $value=$elementclone->getLabel();
                    $elementclone->setLabel(str_replace('{no}', ($i+1), $value));

                }

                $mform->addElement($elementclone);
            }
        }
        for ($i=0; $i<$repeats; $i++) {
            foreach ($options as $elementname => $elementoptions){
                $pos=strpos($elementname, '[');
                if ($pos!==FALSE){
                    $realelementname = substr($elementname, 0, $pos+1)."[$i]";
                    $realelementname .= substr($elementname, $pos+1);
                }else {
                    $realelementname = $elementname."[$i]";
                }
                foreach ($elementoptions as  $option => $params){

                    switch ($option){
                        case 'default' :
                            $mform->setDefault($realelementname, $params);
                            break;
                        case 'helpbutton' :
                            $mform->setHelpButton($realelementname, $params);
                            break;
                        case 'disabledif' :
                            foreach ($namecloned as $num => $name){
                                if ($params[0] == $name){
                                    $params[0] = $params[0]."[$i]";
                                    break;
                                }
                            }
                            $params = array_merge(array($realelementname), $params);
                            call_user_func_array(array(&$mform, 'disabledIf'), $params);
                            break;
                        case 'rule' :
                            if (is_string($params)){
                                $params = array(null, $params, null, 'client');
                            }
                            $params = array_merge(array($realelementname), $params);
                            call_user_func_array(array(&$mform, 'addRule'), $params);
                            break;

                    }
                }
            }
        }
        $mform->addElement('submit', $addfieldsname, $addstring);

        if (!$addbuttoninside) {
            $mform->closeHeaderBefore($addfieldsname);
        }

        return $repeats;
    }

    /**
     * Adds a link/button that controls the checked state of a group of checkboxes.
     * @param int    $groupid The id of the group of advcheckboxes this element controls
     * @param string $text The text of the link. Defaults to selectallornone ("select all/none")
     * @param array  $attributes associative array of HTML attributes
     * @param int    $originalValue The original general state of the checkboxes before the user first clicks this element
     */
    function add_checkbox_controller($groupid, $text = null, $attributes = null, $originalValue = 0) {
        global $CFG;

        // Set the default text if none was specified
        if (empty($text)) {
            $text = get_string('selectallornone', 'form');
        }

        $mform = $this->_form;
        $select_value = optional_param('checkbox_controller'. $groupid, null, PARAM_INT);

        if ($select_value == 0 || is_null($select_value)) {
            $new_select_value = 1;
        } else {
            $new_select_value = 0;
        }

        $mform->addElement('hidden', "checkbox_controller$groupid");
        $mform->setType("checkbox_controller$groupid", PARAM_INT);
        $mform->setConstants(array("checkbox_controller$groupid" => $new_select_value));

        // Locate all checkboxes for this group and set their value, IF the optional param was given
        if (!is_null($select_value)) {
            foreach ($this->_form->_elements as $element) {
                if ($element->getAttribute('class') == "checkboxgroup$groupid") {
                    $mform->setConstants(array($element->getAttribute('name') => $select_value));
                }
            }
        }

        $checkbox_controller_name = 'nosubmit_checkbox_controller' . $groupid;
        $mform->registerNoSubmitButton($checkbox_controller_name);

        // Prepare Javascript for submit element
        $js = "\n//<![CDATA[\n";
        if (!defined('HTML_QUICKFORM_CHECKBOXCONTROLLER_EXISTS')) {
            $js .= <<<EOS
function html_quickform_toggle_checkboxes(group) {
    var checkboxes = getElementsByClassName(document, 'input', 'checkboxgroup' + group);
    var newvalue = false;
    var global = eval('html_quickform_checkboxgroup' + group + ';');
    if (global == 1) {
        eval('html_quickform_checkboxgroup' + group + ' = 0;');
        newvalue = '';
    } else {
        eval('html_quickform_checkboxgroup' + group + ' = 1;');
        newvalue = 'checked';
    }

    for (i = 0; i < checkboxes.length; i++) {
        checkboxes[i].checked = newvalue;
    }
}
EOS;
            define('HTML_QUICKFORM_CHECKBOXCONTROLLER_EXISTS', true);
        }
        $js .= "\nvar html_quickform_checkboxgroup$groupid=$originalValue;\n";

        $js .= "//]]>\n";

        require_once("$CFG->libdir/form/submitlink.php");
        $submitlink = new MoodleQuickForm_submitlink($checkbox_controller_name, $attributes);
        $submitlink->_js = $js;
        $submitlink->_onclick = "html_quickform_toggle_checkboxes($groupid); return false;";
        $mform->addElement($submitlink);
        $mform->setDefault($checkbox_controller_name, $text);
    }

    /**
     * Use this method to a cancel and submit button to the end of your form. Pass a param of false
     * if you don't want a cancel button in your form. If you have a cancel button make sure you
     * check for it being pressed using is_cancelled() and redirecting if it is true before trying to
     * get data with get_data().
     *
     * @param boolean $cancel whether to show cancel button, default true
     * @param string $submitlabel label for submit button, defaults to get_string('savechanges')
     */
    function add_action_buttons($cancel = true, $submitlabel=null){
        if (is_null($submitlabel)){
            $submitlabel = get_string('savechanges');
        }
        $mform =& $this->_form;
        if ($cancel){
            //when two elements we need a group
            $buttonarray=array();
            $buttonarray[] = &$mform->createElement('submit', 'submitbutton', $submitlabel);
            $buttonarray[] = &$mform->createElement('cancel');
            $mform->addGroup($buttonarray, 'buttonar', '', array(' '), false);
            $mform->closeHeaderBefore('buttonar');
        } else {
            //no group needed
            $mform->addElement('submit', 'submitbutton', $submitlabel);
            $mform->closeHeaderBefore('submitbutton');
        }
    }
}

/**
 * You never extend this class directly. The class methods of this class are available from
 * the private $this->_form property on moodleform and its children. You generally only
 * call methods on this class from within abstract methods that you override on moodleform such
 * as definition and definition_after_data
 *
 */
class MoodleQuickForm extends HTML_QuickForm_DHTMLRulesTableless {
    var $_types = array();
    var $_dependencies = array();
    /**
     * Array of buttons that if pressed do not result in the processing of the form.
     *
     * @var array
     */
    var $_noSubmitButtons=array();
    /**
     * Array of buttons that if pressed do not result in the processing of the form.
     *
     * @var array
     */
    var $_cancelButtons=array();

    /**
     * Array whose keys are element names. If the key exists this is a advanced element
     *
     * @var array
     */
    var $_advancedElements = array();

    /**
     * Whether to display advanced elements (on page load)
     *
     * @var boolean
     */
    var $_showAdvanced = null;

    /**
     * The form name is derrived from the class name of the wrapper minus the trailing form
     * It is a name with words joined by underscores whereas the id attribute is words joined by
     * underscores.
     *
     * @var unknown_type
     */
    var $_formName = '';

    /**
     * String with the html for hidden params passed in as part of a moodle_url object for the action. Output in the form.
     *
     * @var string
     */
    var $_pageparams = '';

    /**
     * Class constructor - same parameters as HTML_QuickForm_DHTMLRulesTableless
     * @param    string      $formName          Form's name.
     * @param    string      $method            (optional)Form's method defaults to 'POST'
     * @param    mixed      $action             (optional)Form's action - string or moodle_url
     * @param    string      $target            (optional)Form's target defaults to none
     * @param    mixed       $attributes        (optional)Extra attributes for <form> tag
     * @param    bool        $trackSubmit       (optional)Whether to track if the form was submitted by adding a special hidden field
     * @access   public
     */
    function MoodleQuickForm($formName, $method, $action, $target='', $attributes=null){
        global $CFG;

        static $formcounter = 1;

        HTML_Common::HTML_Common($attributes);
        $target = empty($target) ? array() : array('target' => $target);
        $this->_formName = $formName;
        if (is_a($action, 'moodle_url')){
            $this->_pageparams = $action->hidden_params_out();
            $action = $action->out(true);
        } else {
            $this->_pageparams = '';
        }
        //no 'name' atttribute for form in xhtml strict :
        $attributes = array('action'=>$action, 'method'=>$method,
                'accept-charset'=>'utf-8', 'id'=>'mform'.$formcounter) + $target;
        $formcounter++;
        $this->updateAttributes($attributes);

        //this is custom stuff for Moodle :
        $oldclass=   $this->getAttribute('class');
        if (!empty($oldclass)){
            $this->updateAttributes(array('class'=>$oldclass.' mform'));
        }else {
            $this->updateAttributes(array('class'=>'mform'));
        }
        $this->_reqHTML = '<img class="req" title="'.get_string('requiredelement', 'form').'" alt="'.get_string('requiredelement', 'form').'" src="'.$CFG->pixpath.'/req.gif'.'" />';
        $this->_advancedHTML = '<img class="adv" title="'.get_string('advancedelement', 'form').'" alt="'.get_string('advancedelement', 'form').'" src="'.$CFG->pixpath.'/adv.gif'.'" />';
        $this->setRequiredNote(get_string('somefieldsrequired', 'form', '<img alt="'.get_string('requiredelement', 'form').'" src="'.$CFG->pixpath.'/req.gif'.'" />'));
        //(Help file doesn't add anything) helpbutton('requiredelement', get_string('requiredelement', 'form'), 'moodle', true, false, '', true));
    }

    /**
     * Use this method to indicate an element in a form is an advanced field. If items in a form
     * are marked as advanced then 'Hide/Show Advanced' buttons will automatically be displayed in the
     * form so the user can decide whether to display advanced form controls.
     *
     * If you set a header element to advanced then all elements it contains will also be set as advanced.
     *
     * @param string $elementName group or element name (not the element name of something inside a group).
     * @param boolean $advanced default true sets the element to advanced. False removes advanced mark.
     */
    function setAdvanced($elementName, $advanced=true){
        if ($advanced){
            $this->_advancedElements[$elementName]='';
        } elseif (isset($this->_advancedElements[$elementName])) {
            unset($this->_advancedElements[$elementName]);
        }
        if ($advanced && $this->getElementType('mform_showadvanced_last')===false){
            $this->setShowAdvanced();
            $this->registerNoSubmitButton('mform_showadvanced');

            $this->addElement('hidden', 'mform_showadvanced_last');
            $this->setType('mform_showadvanced_last', PARAM_INT);
        }
    }
    /**
     * Set whether to show advanced elements in the form on first displaying form. Default is not to
     * display advanced elements in the form until 'Show Advanced' is pressed.
     *
     * You can get the last state of the form and possibly save it for this user by using
     * value 'mform_showadvanced_last' in submitted data.
     *
     * @param boolean $showadvancedNow
     */
    function setShowAdvanced($showadvancedNow = null){
        if ($showadvancedNow === null){
            if ($this->_showAdvanced !== null){
                return;
            } else { //if setShowAdvanced is called without any preference
                     //make the default to not show advanced elements.
                $showadvancedNow = get_user_preferences(
                                moodle_strtolower($this->_formName.'_showadvanced', 0));
            }
        }
        //value of hidden element
        $hiddenLast = optional_param('mform_showadvanced_last', -1, PARAM_INT);
        //value of button
        $buttonPressed = optional_param('mform_showadvanced', 0, PARAM_RAW);
        //toggle if button pressed or else stay the same
        if ($hiddenLast == -1) {
            $next = $showadvancedNow;
        } elseif ($buttonPressed) { //toggle on button press
            $next = !$hiddenLast;
        } else {
            $next = $hiddenLast;
        }
        $this->_showAdvanced = $next;
        if ($showadvancedNow != $next){
            set_user_preference($this->_formName.'_showadvanced', $next);
        }
        $this->setConstants(array('mform_showadvanced_last'=>$next));
    }
    function getShowAdvanced(){
        return $this->_showAdvanced;
    }


   /**
    * Accepts a renderer
    *
    * @param HTML_QuickForm_Renderer  An HTML_QuickForm_Renderer object
    * @since 3.0
    * @access public
    * @return void
    */
    function accept(&$renderer) {
        if (method_exists($renderer, 'setAdvancedElements')){
            //check for visible fieldsets where all elements are advanced
            //and mark these headers as advanced as well.
            //And mark all elements in a advanced header as advanced
            $stopFields = $renderer->getStopFieldSetElements();
            $lastHeader = null;
            $lastHeaderAdvanced = false;
            $anyAdvanced = false;
            foreach (array_keys($this->_elements) as $elementIndex){
                $element =& $this->_elements[$elementIndex];

                // if closing header and any contained element was advanced then mark it as advanced
                if ($element->getType()=='header' || in_array($element->getName(), $stopFields)){
                    if ($anyAdvanced && !is_null($lastHeader)){
                        $this->setAdvanced($lastHeader->getName());
                    }
                    $lastHeaderAdvanced = false;
                    unset($lastHeader);
                    $lastHeader = null;
                } elseif ($lastHeaderAdvanced) {
                    $this->setAdvanced($element->getName());
                }

                if ($element->getType()=='header'){
                    $lastHeader =& $element;
                    $anyAdvanced = false;
                    $lastHeaderAdvanced = isset($this->_advancedElements[$element->getName()]);
                } elseif (isset($this->_advancedElements[$element->getName()])){
                    $anyAdvanced = true;
                }
            }
            // the last header may not be closed yet...
            if ($anyAdvanced && !is_null($lastHeader)){
                $this->setAdvanced($lastHeader->getName());
            }
            $renderer->setAdvancedElements($this->_advancedElements);

        }
        parent::accept($renderer);
    }



    function closeHeaderBefore($elementName){
        $renderer =& $this->defaultRenderer();
        $renderer->addStopFieldsetElements($elementName);
    }

    /**
     * Should be used for all elements of a form except for select, radio and checkboxes which
     * clean their own data.
     *
     * @param string $elementname
     * @param integer $paramtype use the constants PARAM_*.
     *     *  PARAM_CLEAN is deprecated and you should try to use a more specific type.
     *     *  PARAM_TEXT should be used for cleaning data that is expected to be plain text.
     *          It will strip all html tags. But will still let tags for multilang support
     *          through.
     *     *  PARAM_RAW means no cleaning whatsoever, it is used mostly for data from the
     *          html editor. Data from the editor is later cleaned before display using
     *          format_text() function. PARAM_RAW can also be used for data that is validated
     *          by some other way or printed by p() or s().
     *     *  PARAM_INT should be used for integers.
     *     *  PARAM_ACTION is an alias of PARAM_ALPHA and is used for hidden fields specifying
     *          form actions.
     */
    function setType($elementname, $paramtype) {
        $this->_types[$elementname] = $paramtype;
    }

    /**
     * See description of setType above. This can be used to set several types at once.
     *
     * @param array $paramtypes
     */
    function setTypes($paramtypes) {
        $this->_types = $paramtypes + $this->_types;
    }

    function updateSubmission($submission, $files) {
        $this->_flagSubmitted = false;

        if (empty($submission)) {
            $this->_submitValues = array();
        } else {
            foreach ($submission as $key=>$s) {
                if (array_key_exists($key, $this->_types)) {
                    $submission[$key] = clean_param($s, $this->_types[$key]);
                }
            }
            $this->_submitValues = $this->_recursiveFilter('stripslashes', $submission);
            $this->_flagSubmitted = true;
        }

        if (empty($files)) {
            $this->_submitFiles = array();
        } else {
            if (1 == get_magic_quotes_gpc()) {
                foreach (array_keys($files) as $elname) {
                    // dangerous characters in filenames are cleaned later in upload_manager
                    $files[$elname]['name'] = stripslashes($files[$elname]['name']);
                }
            }
            $this->_submitFiles = $files;
            $this->_flagSubmitted = true;
        }

        // need to tell all elements that they need to update their value attribute.
         foreach (array_keys($this->_elements) as $key) {
             $this->_elements[$key]->onQuickFormEvent('updateValue', null, $this);
         }
    }

    function getReqHTML(){
        return $this->_reqHTML;
    }

    function getAdvancedHTML(){
        return $this->_advancedHTML;
    }

    /**
     * Initializes a default form value. Used to specify the default for a new entry where
     * no data is loaded in using moodleform::set_data()
     *
     * @param     string   $elementname        element name
     * @param     mixed    $values             values for that element name
     * @param     bool     $slashed            the default value is slashed
     * @access    public
     * @return    void
     */
    function setDefault($elementName, $defaultValue, $slashed=false){
        $filter = $slashed ? 'stripslashes' : NULL;
        $this->setDefaults(array($elementName=>$defaultValue), $filter);
    } // end func setDefault
    /**
     * Add an array of buttons to the form
     * @param    array       $buttons          An associative array representing help button to attach to
     *                                          to the form. keys of array correspond to names of elements in form.
     *
     * @access   public
    */
    function setHelpButtons($buttons, $suppresscheck=false, $function='helpbutton'){

        foreach ($buttons as $elementname => $button){
            $this->setHelpButton($elementname, $button, $suppresscheck, $function);
        }
    }
    /**
     * Add a single button.
     *
     * @param string $elementname name of the element to add the item to
     * @param array $button - arguments to pass to function $function
     * @param boolean $suppresscheck - whether to throw an error if the element
     *                                  doesn't exist.
     * @param string $function - function to generate html from the arguments in $button
     */
    function setHelpButton($elementname, $button, $suppresscheck=false, $function='helpbutton'){
        if (array_key_exists($elementname, $this->_elementIndex)){
            //_elements has a numeric index, this code accesses the elements by name
            $element=&$this->_elements[$this->_elementIndex[$elementname]];
            if (method_exists($element, 'setHelpButton')){
                $element->setHelpButton($button, $function);
            }else{
                $a=new object();
                $a->name=$element->getName();
                $a->classname=get_class($element);
                print_error('nomethodforaddinghelpbutton', 'form', '', $a);
            }
        }elseif (!$suppresscheck){
            print_error('nonexistentformelements', 'form', '', $elementname);
        }
    }

    /**
     * Set constant value not overriden by _POST or _GET
     * note: this does not work for complex names with [] :-(
     * @param string $elname name of element
     * @param mixed $value
     * @return void
     */
    function setConstant($elname, $value) {
        $this->_constantValues = HTML_QuickForm::arrayMerge($this->_constantValues, array($elname=>$value));
        $element =& $this->getElement($elname);
        $element->onQuickFormEvent('updateValue', null, $this);
    }

    function exportValues($elementList= null, $addslashes=true){
        $unfiltered = array();
        if (null === $elementList) {
            // iterate over all elements, calling their exportValue() methods
            $emptyarray = array();
            foreach (array_keys($this->_elements) as $key) {
                if ($this->_elements[$key]->isFrozen() && !$this->_elements[$key]->_persistantFreeze){
                    $value = $this->_elements[$key]->exportValue($emptyarray, true);
                } else {
                    $value = $this->_elements[$key]->exportValue($this->_submitValues, true);
                }

                if (is_array($value)) {
                    // This shit throws a bogus warning in PHP 4.3.x
                    $unfiltered = HTML_QuickForm::arrayMerge($unfiltered, $value);
                }
            }
        } else {
            if (!is_array($elementList)) {
                $elementList = array_map('trim', explode(',', $elementList));
            }
            foreach ($elementList as $elementName) {
                $value = $this->exportValue($elementName);
                if (PEAR::isError($value)) {
                    return $value;
                }
                $unfiltered[$elementName] = $value;
            }
        }

        if (is_array($this->_constantValues)) {
            $unfiltered = HTML_QuickForm::arrayMerge($unfiltered, $this->_constantValues);
        }

        if ($addslashes){
            return $this->_recursiveFilter('addslashes', $unfiltered);
        } else {
            return $unfiltered;
        }
    }
    /**
     * Adds a validation rule for the given field
     *
     * If the element is in fact a group, it will be considered as a whole.
     * To validate grouped elements as separated entities,
     * use addGroupRule instead of addRule.
     *
     * @param    string     $element       Form element name
     * @param    string     $message       Message to display for invalid data
     * @param    string     $type          Rule type, use getRegisteredRules() to get types
     * @param    string     $format        (optional)Required for extra rule data
     * @param    string     $validation    (optional)Where to perform validation: "server", "client"
     * @param    boolean    $reset         Client-side validation: reset the form element to its original value if there is an error?
     * @param    boolean    $force         Force the rule to be applied, even if the target form element does not exist
     * @since    1.0
     * @access   public
     * @throws   HTML_QuickForm_Error
     */
    function addRule($element, $message, $type, $format=null, $validation='server', $reset = false, $force = false)
    {
        parent::addRule($element, $message, $type, $format, $validation, $reset, $force);
        if ($validation == 'client') {
            $this->updateAttributes(array('onsubmit' => 'try { var myValidator = validate_' . $this->_formName . '; } catch(e) { return true; } return myValidator(this);'));
        }

    } // end func addRule
    /**
     * Adds a validation rule for the given group of elements
     *
     * Only groups with a name can be assigned a validation rule
     * Use addGroupRule when you need to validate elements inside the group.
     * Use addRule if you need to validate the group as a whole. In this case,
     * the same rule will be applied to all elements in the group.
     * Use addRule if you need to validate the group against a function.
     *
     * @param    string     $group         Form group name
     * @param    mixed      $arg1          Array for multiple elements or error message string for one element
     * @param    string     $type          (optional)Rule type use getRegisteredRules() to get types
     * @param    string     $format        (optional)Required for extra rule data
     * @param    int        $howmany       (optional)How many valid elements should be in the group
     * @param    string     $validation    (optional)Where to perform validation: "server", "client"
     * @param    bool       $reset         Client-side: whether to reset the element's value to its original state if validation failed.
     * @since    2.5
     * @access   public
     * @throws   HTML_QuickForm_Error
     */
    function addGroupRule($group, $arg1, $type='', $format=null, $howmany=0, $validation = 'server', $reset = false)
    {
        parent::addGroupRule($group, $arg1, $type, $format, $howmany, $validation, $reset);
        if (is_array($arg1)) {
             foreach ($arg1 as $rules) {
                foreach ($rules as $rule) {
                    $validation = (isset($rule[3]) && 'client' == $rule[3])? 'client': 'server';

                    if ('client' == $validation) {
                        $this->updateAttributes(array('onsubmit' => 'try { var myValidator = validate_' . $this->_formName . '; } catch(e) { return true; } return myValidator(this);'));
                    }
                }
            }
        } elseif (is_string($arg1)) {

            if ($validation == 'client') {
                $this->updateAttributes(array('onsubmit' => 'try { var myValidator = validate_' . $this->_formName . '; } catch(e) { return true; } return myValidator(this);'));
            }
        }
    } // end func addGroupRule

    // }}}
    /**
     * Returns the client side validation script
     *
     * The code here was copied from HTML_QuickForm_DHTMLRulesTableless who copied it from  HTML_QuickForm
     * and slightly modified to run rules per-element
     * Needed to override this because of an error with client side validation of grouped elements.
     *
     * @access    public
     * @return    string    Javascript to perform validation, empty string if no 'client' rules were added
     */
    function getValidationScript()
    {
        if (empty($this->_rules) || empty($this->_attributes['onsubmit'])) {
            return '';
        }

        include_once('HTML/QuickForm/RuleRegistry.php');
        $registry =& HTML_QuickForm_RuleRegistry::singleton();
        $test = array();
        $js_escape = array(
            "\r"    => '\r',
            "\n"    => '\n',
            "\t"    => '\t',
            "'"     => "\\'",
            '"'     => '\"',
            '\\'    => '\\\\'
        );

        foreach ($this->_rules as $elementName => $rules) {
            foreach ($rules as $rule) {
                if ('client' == $rule['validation']) {
                    unset($element); //TODO: find out how to properly initialize it

                    $dependent  = isset($rule['dependent']) && is_array($rule['dependent']);
                    $rule['message'] = strtr($rule['message'], $js_escape);

                    if (isset($rule['group'])) {
                        $group    =& $this->getElement($rule['group']);
                        // No JavaScript validation for frozen elements
                        if ($group->isFrozen()) {
                            continue 2;
                        }
                        $elements =& $group->getElements();
                        foreach (array_keys($elements) as $key) {
                            if ($elementName == $group->getElementName($key)) {
                                $element =& $elements[$key];
                                break;
                            }
                        }
                    } elseif ($dependent) {
                        $element   =  array();
                        $element[] =& $this->getElement($elementName);
                        foreach ($rule['dependent'] as $elName) {
                            $element[] =& $this->getElement($elName);
                        }
                    } else {
                        $element =& $this->getElement($elementName);
                    }
                    // No JavaScript validation for frozen elements
                    if (is_object($element) && $element->isFrozen()) {
                        continue 2;
                    } elseif (is_array($element)) {
                        foreach (array_keys($element) as $key) {
                            if ($element[$key]->isFrozen()) {
                                continue 3;
                            }
                        }
                    }
                    // Fix for bug displaying errors for elements in a group
                    //$test[$elementName][] = $registry->getValidationScript($element, $elementName, $rule);
                    $test[$elementName][0][] = $registry->getValidationScript($element, $elementName, $rule);
                    $test[$elementName][1]=$element;
                    //end of fix
                }
            }
        }

        // Fix for MDL-9524. If you don't do this, then $element may be left as a reference to one of the fields in
        // the form, and then that form field gets corrupted by the code that follows.
        unset($element);

        $js = '
<script type="text/javascript">
//<![CDATA[

var skipClientValidation = false;

function qf_errorHandler(element, _qfMsg) {
  div = element.parentNode;
  if (_qfMsg != \'\') {
    var errorSpan = document.getElementById(\'id_error_\'+element.name);
    if (!errorSpan) {
      errorSpan = document.createElement("span");
      errorSpan.id = \'id_error_\'+element.name;
      errorSpan.className = "error";
      element.parentNode.insertBefore(errorSpan, element.parentNode.firstChild);
    }

    while (errorSpan.firstChild) {
      errorSpan.removeChild(errorSpan.firstChild);
    }

    errorSpan.appendChild(document.createTextNode(_qfMsg.substring(3)));
    errorSpan.appendChild(document.createElement("br"));

    if (div.className.substr(div.className.length - 6, 6) != " error"
        && div.className != "error") {
      div.className += " error";
    }

    return false;
  } else {
    var errorSpan = document.getElementById(\'id_error_\'+element.name);
    if (errorSpan) {
      errorSpan.parentNode.removeChild(errorSpan);
    }

    if (div.className.substr(div.className.length - 6, 6) == " error") {
      div.className = div.className.substr(0, div.className.length - 6);
    } else if (div.className == "error") {
      div.className = "";
    }

    return true;
  }
}';
        $validateJS = '';
        foreach ($test as $elementName => $jsandelement) {
            // Fix for bug displaying errors for elements in a group
            //unset($element);
            list($jsArr,$element)=$jsandelement;
            //end of fix
            $escapedElementName = preg_replace_callback(
                '/[_\[\]]/',
                create_function('$matches', 'return sprintf("_%2x",ord($matches[0]));'),
                $elementName);
            $js .= '
function validate_' . $this->_formName . '_' . $escapedElementName . '(element) {
  var value = \'\';
  var errFlag = new Array();
  var _qfGroups = {};
  var _qfMsg = \'\';
  var frm = element.parentNode;
  while (frm && frm.nodeName.toUpperCase() != "FORM") {
    frm = frm.parentNode;
  }
' . join("\n", $jsArr) . '
  return qf_errorHandler(element, _qfMsg);
}
';
            $validateJS .= '
  ret = validate_' . $this->_formName . '_' . $escapedElementName.'(frm.elements[\''.$elementName.'\']) && ret;
  if (!ret && !first_focus) {
    first_focus = true;
    frm.elements[\''.$elementName.'\'].focus();
  }
';

            // Fix for bug displaying errors for elements in a group
            //unset($element);
            //$element =& $this->getElement($elementName);
            //end of fix
            $valFunc = 'validate_' . $this->_formName . '_' . $escapedElementName . '(this)';
            $onBlur = $element->getAttribute('onBlur');
            $onChange = $element->getAttribute('onChange');
            $element->updateAttributes(array('onBlur' => $onBlur . $valFunc,
                                             'onChange' => $onChange . $valFunc));
        }
//  do not rely on frm function parameter, because htmlarea breaks it when overloading the onsubmit method
        $js .= '
function validate_' . $this->_formName . '(frm) {
  if (skipClientValidation) {
     return true;
  }
  var ret = true;

  var frm = document.getElementById(\''. $this->_attributes['id'] .'\')
  var first_focus = false;
' . $validateJS . ';
  return ret;
}
//]]>
</script>';
        return $js;
    } // end func getValidationScript
    function _setDefaultRuleMessages(){
        foreach ($this->_rules as $field => $rulesarr){
            foreach ($rulesarr as $key => $rule){
                if ($rule['message']===null){
                    $a=new object();
                    $a->format=$rule['format'];
                    $str=get_string('err_'.$rule['type'], 'form', $a);
                    if (strpos($str, '[[')!==0){
                        $this->_rules[$field][$key]['message']=$str;
                    }
                }
            }
        }
    }

    function getLockOptionEndScript(){

        $iname = $this->getAttribute('id').'items';
        $js = '<script type="text/javascript">'."\n";
        $js .= '//<![CDATA['."\n";
        $js .= "var $iname = Array();\n";

        foreach ($this->_dependencies as $dependentOn => $conditions){
            $js .= "{$iname}['$dependentOn'] = Array();\n";
            foreach ($conditions as $condition=>$values) {
                $js .= "{$iname}['$dependentOn']['$condition'] = Array();\n";
                foreach ($values as $value=>$dependents) {
                    $js .= "{$iname}['$dependentOn']['$condition']['$value'] = Array();\n";
                    $i = 0;
                    foreach ($dependents as $dependent) {
                        $elements = $this->_getElNamesRecursive($dependent);
                        if (empty($elements)) {
                            // probably element inside of some group
                            $elements = array($dependent);
                        }
                        foreach($elements as $element) {
                            if ($element == $dependentOn) {
                                continue;
                            }
                            $js .= "{$iname}['$dependentOn']['$condition']['$value'][$i]='$element';\n";
                            $i++;
                        }
                    }
                }
            }
        }
        $js .="lockoptionsallsetup('".$this->getAttribute('id')."');\n";
        $js .='//]]>'."\n";
        $js .='</script>'."\n";
        return $js;
    }

    function _getElNamesRecursive($element) {
        if (is_string($element)) {
            if (!$this->elementExists($element)) {
                return array();
            }
            $element = $this->getElement($element);
        }

        if (is_a($element, 'HTML_QuickForm_group')) {
            $elsInGroup = $element->getElements();
            $elNames = array();
            foreach ($elsInGroup as $elInGroup){
                if (is_a($elInGroup, 'HTML_QuickForm_group')) {
                    // not sure if this would work - groups nested in groups
                    $elNames = array_merge($elNames, $this->_getElNamesRecursive($elInGroup));
                } else {
                    $elNames[] = $element->getElementName($elInGroup->getName());
                }
            }

        } else if (is_a($element, 'HTML_QuickForm_header')) {
            return array();

        } else if (is_a($element, 'HTML_QuickForm_hidden')) {
            return array();

        } else if (method_exists($element, 'getPrivateName')) {
            return array($element->getPrivateName());

        } else {
            $elNames = array($element->getName());
        }

        return $elNames;
    }

    /**
     * Adds a dependency for $elementName which will be disabled if $condition is met.
     * If $condition = 'notchecked' (default) then the condition is that the $dependentOn element
     * is not checked. If $condition = 'checked' then the condition is that the $dependentOn element
     * is checked. If $condition is something else (like "eq" for equals) then it is checked to see if the value
     * of the $dependentOn element is $condition (such as equal) to $value.
     *
     * @param string $elementName the name of the element which will be disabled
     * @param string $dependentOn the name of the element whose state will be checked for
     *                            condition
     * @param string $condition the condition to check
     * @param mixed $value used in conjunction with condition.
     */
    function disabledIf($elementName, $dependentOn, $condition = 'notchecked', $value='1'){
        if (!array_key_exists($dependentOn, $this->_dependencies)) {
            $this->_dependencies[$dependentOn] = array();
        }
        if (!array_key_exists($condition, $this->_dependencies[$dependentOn])) {
            $this->_dependencies[$dependentOn][$condition] = array();
        }
        if (!array_key_exists($value, $this->_dependencies[$dependentOn][$condition])) {
            $this->_dependencies[$dependentOn][$condition][$value] = array();
        }
        $this->_dependencies[$dependentOn][$condition][$value][] = $elementName;
    }

    function registerNoSubmitButton($buttonname){
        $this->_noSubmitButtons[]=$buttonname;
    }

    function isNoSubmitButton($buttonname){
        return (array_search($buttonname, $this->_noSubmitButtons)!==FALSE);
    }

    function _registerCancelButton($addfieldsname){
        $this->_cancelButtons[]=$addfieldsname;
    }
    /**
     * Displays elements without HTML input tags.
     * This method is different to freeze() in that it makes sure no hidden
     * elements are included in the form.
     * Note: If you want to make sure the submitted value is ignored, please use setDefaults().
     *
     * This function also removes all previously defined rules.
     *
     * @param    mixed   $elementList       array or string of element(s) to be frozen
     * @since     1.0
     * @access   public
     * @throws   HTML_QuickForm_Error
     */
    function hardFreeze($elementList=null)
    {
        if (!isset($elementList)) {
            $this->_freezeAll = true;
            $elementList = array();
        } else {
            if (!is_array($elementList)) {
                $elementList = preg_split('/[ ]*,[ ]*/', $elementList);
            }
            $elementList = array_flip($elementList);
        }

        foreach (array_keys($this->_elements) as $key) {
            $name = $this->_elements[$key]->getName();
            if ($this->_freezeAll || isset($elementList[$name])) {
                $this->_elements[$key]->freeze();
                $this->_elements[$key]->setPersistantFreeze(false);
                unset($elementList[$name]);

                // remove all rules
                $this->_rules[$name] = array();
                // if field is required, remove the rule
                $unset = array_search($name, $this->_required);
                if ($unset !== false) {
                    unset($this->_required[$unset]);
                }
            }
        }

        if (!empty($elementList)) {
            return PEAR::raiseError(null, QUICKFORM_NONEXIST_ELEMENT, null, E_USER_WARNING, "Nonexistant element(s): '" . implode("', '", array_keys($elementList)) . "' in HTML_QuickForm::freeze()", 'HTML_QuickForm_Error', true);
        }
        return true;
    }
    /**
     * Hard freeze all elements in a form except those whose names are in $elementList or hidden elements in a form.
     *
     * This function also removes all previously defined rules of elements it freezes.
     *
     * @param    array   $elementList       array or string of element(s) not to be frozen
     * @since     1.0
     * @access   public
     * @throws   HTML_QuickForm_Error
     */
    function hardFreezeAllVisibleExcept($elementList)
    {
        $elementList = array_flip($elementList);
        foreach (array_keys($this->_elements) as $key) {
            $name = $this->_elements[$key]->getName();
            $type = $this->_elements[$key]->getType();

            if ($type == 'hidden'){
                // leave hidden types as they are
            } elseif (!isset($elementList[$name])) {
                $this->_elements[$key]->freeze();
                $this->_elements[$key]->setPersistantFreeze(false);

                // remove all rules
                $this->_rules[$name] = array();
                // if field is required, remove the rule
                $unset = array_search($name, $this->_required);
                if ($unset !== false) {
                    unset($this->_required[$unset]);
                }
            }
        }
        return true;
    }
   /**
    * Tells whether the form was already submitted
    *
    * This is useful since the _submitFiles and _submitValues arrays
    * may be completely empty after the trackSubmit value is removed.
    *
    * @access public
    * @return bool
    */
    function isSubmitted()
    {
        return parent::isSubmitted() && (!$this->isFrozen());
    }
}


/**
 * A renderer for MoodleQuickForm that only uses XHTML and CSS and no
 * table tags, extends PEAR class HTML_QuickForm_Renderer_Tableless
 *
 * Stylesheet is part of standard theme and should be automatically included.
 *
 * @author      Jamie Pratt <me@jamiep.org>
 * @license    gpl license
 */
class MoodleQuickForm_Renderer extends HTML_QuickForm_Renderer_Tableless{

    /**
    * Element template array
    * @var      array
    * @access   private
    */
    var $_elementTemplates;
    /**
    * Template used when opening a hidden fieldset
    * (i.e. a fieldset that is opened when there is no header element)
    * @var      string
    * @access   private
    */
    var $_openHiddenFieldsetTemplate = "\n\t<fieldset class=\"hidden\"><div>";
   /**
    * Header Template string
    * @var      string
    * @access   private
    */
    var $_headerTemplate =
       "\n\t\t<legend class=\"ftoggler\">{header}</legend>\n\t\t<div class=\"advancedbutton\">{advancedimg}{button}</div><div class=\"fcontainer clearfix\">\n\t\t";

   /**
    * Template used when opening a fieldset
    * @var      string
    * @access   private
    */
    var $_openFieldsetTemplate = "\n\t<fieldset class=\"clearfix\" {id}>";

    /**
    * Template used when closing a fieldset
    * @var      string
    * @access   private
    */
    var $_closeFieldsetTemplate = "\n\t\t</div></fieldset>";

   /**
    * Required Note template string
    * @var      string
    * @access   private
    */
    var $_requiredNoteTemplate =
        "\n\t\t<div class=\"fdescription required\">{requiredNote}</div>";

    var $_advancedElements = array();

    /**
     * Whether to display advanced elements (on page load)
     *
     * @var integer 1 means show 0 means hide
     */
    var $_showAdvanced;

    function MoodleQuickForm_Renderer(){
        // switch next two lines for ol li containers for form items.
        //        $this->_elementTemplates=array('default'=>"\n\t\t".'<li class="fitem"><label>{label}{help}<!-- BEGIN required -->{req}<!-- END required --></label><div class="qfelement<!-- BEGIN error --> error<!-- END error --> {type}"><!-- BEGIN error --><span class="error">{error}</span><br /><!-- END error -->{element}</div></li>');
        $this->_elementTemplates = array(
        'default'=>"\n\t\t".'<div class="fitem {advanced}<!-- BEGIN required --> required<!-- END required -->"><div class="fitemtitle"><label>{label}<!-- BEGIN required -->{req}<!-- END required -->{advancedimg} {help}</label></div><div class="felement {type}<!-- BEGIN error --> error<!-- END error -->"><!-- BEGIN error --><span class="error">{error}</span><br /><!-- END error -->{element}</div></div>',

        'fieldset'=>"\n\t\t".'<div class="fitem {advanced}<!-- BEGIN required --> required<!-- END required -->"><div class="fitemtitle"><div class="fgrouplabel"><label>{label}<!-- BEGIN required -->{req}<!-- END required -->{advancedimg} {help}</label></div></div><fieldset class="felement {type}<!-- BEGIN error --> error<!-- END error -->"><!-- BEGIN error --><span class="error">{error}</span><br /><!-- END error -->{element}</fieldset></div>',

        'static'=>"\n\t\t".'<div class="fitem {advanced}"><div class="fitemtitle"><div class="fstaticlabel"><label>{label}<!-- BEGIN required -->{req}<!-- END required -->{advancedimg} {help}</label></div></div><div class="felement fstatic <!-- BEGIN error --> error<!-- END error -->"><!-- BEGIN error --><span class="error">{error}</span><br /><!-- END error -->{element}&nbsp;</div></div>',

        'nodisplay'=>'');

        parent::HTML_QuickForm_Renderer_Tableless();
    }

    function setAdvancedElements($elements){
        $this->_advancedElements = $elements;
    }

    /**
     * What to do when starting the form
     *
     * @param MoodleQuickForm $form
     */
    function startForm(&$form){
        $this->_reqHTML = $form->getReqHTML();
        $this->_elementTemplates = str_replace('{req}', $this->_reqHTML, $this->_elementTemplates);
        $this->_advancedHTML = $form->getAdvancedHTML();
        $this->_showAdvanced = $form->getShowAdvanced();
        parent::startForm($form);
        if ($form->isFrozen()){
            $this->_formTemplate = "\n<div class=\"mform frozen\">\n{content}\n</div>";
        } else {
            $this->_hiddenHtml .= $form->_pageparams;
        }


    }

    function startGroup(&$group, $required, $error){
        if (method_exists($group, 'getElementTemplateType')){
            $html = $this->_elementTemplates[$group->getElementTemplateType()];
        }else{
            $html = $this->_elementTemplates['default'];

        }
        if ($this->_showAdvanced){
            $advclass = ' advanced';
        } else {
            $advclass = ' advanced hide';
        }
        if (isset($this->_advancedElements[$group->getName()])){
            $html =str_replace(' {advanced}', $advclass, $html);
            $html =str_replace('{advancedimg}', $this->_advancedHTML, $html);
        } else {
            $html =str_replace(' {advanced}', '', $html);
            $html =str_replace('{advancedimg}', '', $html);
        }
        if (method_exists($group, 'getHelpButton')){
            $html =str_replace('{help}', $group->getHelpButton(), $html);
        }else{
            $html =str_replace('{help}', '', $html);
        }
        $html =str_replace('{name}', $group->getName(), $html);
        $html =str_replace('{type}', 'fgroup', $html);

        $this->_templates[$group->getName()]=$html;
        // Fix for bug in tableless quickforms that didn't allow you to stop a
        // fieldset before a group of elements.
        // if the element name indicates the end of a fieldset, close the fieldset
        if (   in_array($group->getName(), $this->_stopFieldsetElements)
            && $this->_fieldsetsOpen > 0
           ) {
            $this->_html .= $this->_closeFieldsetTemplate;
            $this->_fieldsetsOpen--;
        }
        parent::startGroup($group, $required, $error);
    }

    function renderElement(&$element, $required, $error){
        //manipulate id of all elements before rendering
        if (!is_null($element->getAttribute('id'))) {
            $id = $element->getAttribute('id');
        } else {
            $id = $element->getName();
        }
        //strip qf_ prefix and replace '[' with '_' and strip ']'
        $id = preg_replace(array('/^qf_|\]/', '/\[/'), array('', '_'), $id);
        if (strpos($id, 'id_') !== 0){
            $element->updateAttributes(array('id'=>'id_'.$id));
        }

        //adding stuff to place holders in template
        if (method_exists($element, 'getElementTemplateType')){
            $html = $this->_elementTemplates[$element->getElementTemplateType()];
        }else{
            $html = $this->_elementTemplates['default'];
        }
        if ($this->_showAdvanced){
            $advclass = ' advanced';
        } else {
            $advclass = ' advanced hide';
        }
        if (isset($this->_advancedElements[$element->getName()])){
            $html =str_replace(' {advanced}', $advclass, $html);
        } else {
            $html =str_replace(' {advanced}', '', $html);
        }
        if (isset($this->_advancedElements[$element->getName()])||$element->getName() == 'mform_showadvanced'){
            $html =str_replace('{advancedimg}', $this->_advancedHTML, $html);
        } else {
            $html =str_replace('{advancedimg}', '', $html);
        }
        $html =str_replace('{type}', 'f'.$element->getType(), $html);
        $html =str_replace('{name}', $element->getName(), $html);
        if (method_exists($element, 'getHelpButton')){
            $html = str_replace('{help}', $element->getHelpButton(), $html);
        }else{
            $html = str_replace('{help}', '', $html);

        }
        if (!isset($this->_templates[$element->getName()])) {
            $this->_templates[$element->getName()] = $html;
        }

        parent::renderElement($element, $required, $error);
    }

    function finishForm(&$form){
        if ($form->isFrozen()){
            $this->_hiddenHtml = '';
        }
        parent::finishForm($form);
        if ((!$form->isFrozen()) && ('' != ($script = $form->getLockOptionEndScript()))) {
            // add a lockoptions script
            $this->_html = $this->_html . "\n" . $script;
        }
    }
   /**
    * Called when visiting a header element
    *
    * @param    object     An HTML_QuickForm_header element being visited
    * @access   public
    * @return   void
    */
    function renderHeader(&$header)    {
        $name = $header->getName();

        $id = empty($name) ? '' : ' id="' . $name . '"';
        $id = preg_replace(array('/\]/', '/\[/'), array('', '_'), $id);
        if (is_null($header->_text)) {
            $header_html = '';
        } elseif (!empty($name) && isset($this->_templates[$name])) {
            $header_html = str_replace('{header}', $header->toHtml(), $this->_templates[$name]);
        } else {
            $header_html = str_replace('{header}', $header->toHtml(), $this->_headerTemplate);
        }

        if (isset($this->_advancedElements[$name])){
            $header_html =str_replace('{advancedimg}', $this->_advancedHTML, $header_html);
        } else {
            $header_html =str_replace('{advancedimg}', '', $header_html);
        }
        $elementName='mform_showadvanced';
        if ($this->_showAdvanced==0){
            $buttonlabel = get_string('showadvanced', 'form');
        } else {
            $buttonlabel = get_string('hideadvanced', 'form');
        }

        if (isset($this->_advancedElements[$name])){
            require_js(array('yui_yahoo', 'yui_event'));
            // this is tricky - the first submit button on form is "clicked" if user presses enter
            // we do not want to "submit" using advanced button if javascript active
            $button_nojs = '<input name="'.$elementName.'" value="'.$buttonlabel.'" type="submit" />';

            $buttonlabel = addslashes_js($buttonlabel);
            $showtext = addslashes_js(get_string('showadvanced', 'form'));
            $hidetext = addslashes_js(get_string('hideadvanced', 'form'));
            $button = '<script id="' . $name . '_script" type="text/javascript">' . "
showAdvancedInit('{$name}_script', '$elementName', '$buttonlabel', '$hidetext', '$showtext');
" . '</script><noscript><div style="display:inline">'.$button_nojs.'</div></noscript>';  // the extra div should fix xhtml validation

            $header_html = str_replace('{button}', $button, $header_html);
        } else {
            $header_html = str_replace('{button}', '', $header_html);
        }

        if ($this->_fieldsetsOpen > 0) {
            $this->_html .= $this->_closeFieldsetTemplate;
            $this->_fieldsetsOpen--;
        }

        $openFieldsetTemplate = str_replace('{id}', $id, $this->_openFieldsetTemplate);
        if ($this->_showAdvanced){
            $advclass = ' class="advanced"';
        } else {
            $advclass = ' class="advanced hide"';
        }
        if (isset($this->_advancedElements[$name])){
            $openFieldsetTemplate = str_replace('{advancedclass}', $advclass, $openFieldsetTemplate);
        } else {
            $openFieldsetTemplate = str_replace('{advancedclass}', '', $openFieldsetTemplate);
        }
        $this->_html .= $openFieldsetTemplate . $header_html;
        $this->_fieldsetsOpen++;
    } // end func renderHeader

    function getStopFieldsetElements(){
        return $this->_stopFieldsetElements;
    }
}


$GLOBALS['_HTML_QuickForm_default_renderer'] =& new MoodleQuickForm_Renderer();

MoodleQuickForm::registerElementType('checkbox', "$CFG->libdir/form/checkbox.php", 'MoodleQuickForm_checkbox');
MoodleQuickForm::registerElementType('file', "$CFG->libdir/form/file.php", 'MoodleQuickForm_file');
MoodleQuickForm::registerElementType('group', "$CFG->libdir/form/group.php", 'MoodleQuickForm_group');
MoodleQuickForm::registerElementType('password', "$CFG->libdir/form/password.php", 'MoodleQuickForm_password');
MoodleQuickForm::registerElementType('passwordunmask', "$CFG->libdir/form/passwordunmask.php", 'MoodleQuickForm_passwordunmask');
MoodleQuickForm::registerElementType('radio', "$CFG->libdir/form/radio.php", 'MoodleQuickForm_radio');
MoodleQuickForm::registerElementType('select', "$CFG->libdir/form/select.php", 'MoodleQuickForm_select');
MoodleQuickForm::registerElementType('selectgroups', "$CFG->libdir/form/selectgroups.php", 'MoodleQuickForm_selectgroups');
MoodleQuickForm::registerElementType('submitlink', "$CFG->libdir/form/submitlink.php", 'MoodleQuickForm_submitlink');
MoodleQuickForm::registerElementType('text', "$CFG->libdir/form/text.php", 'MoodleQuickForm_text');
MoodleQuickForm::registerElementType('textarea', "$CFG->libdir/form/textarea.php", 'MoodleQuickForm_textarea');
MoodleQuickForm::registerElementType('date_selector', "$CFG->libdir/form/dateselector.php", 'MoodleQuickForm_date_selector');
MoodleQuickForm::registerElementType('date_time_selector', "$CFG->libdir/form/datetimeselector.php", 'MoodleQuickForm_date_time_selector');
MoodleQuickForm::registerElementType('htmleditor', "$CFG->libdir/form/htmleditor.php", 'MoodleQuickForm_htmleditor');
MoodleQuickForm::registerElementType('format', "$CFG->libdir/form/format.php", 'MoodleQuickForm_format');
MoodleQuickForm::registerElementType('static', "$CFG->libdir/form/static.php", 'MoodleQuickForm_static');
MoodleQuickForm::registerElementType('hidden', "$CFG->libdir/form/hidden.php", 'MoodleQuickForm_hidden');
MoodleQuickForm::registerElementType('modvisible', "$CFG->libdir/form/modvisible.php", 'MoodleQuickForm_modvisible');
MoodleQuickForm::registerElementType('selectyesno', "$CFG->libdir/form/selectyesno.php", 'MoodleQuickForm_selectyesno');
MoodleQuickForm::registerElementType('modgrade', "$CFG->libdir/form/modgrade.php", 'MoodleQuickForm_modgrade');
MoodleQuickForm::registerElementType('cancel', "$CFG->libdir/form/cancel.php", 'MoodleQuickForm_cancel');
MoodleQuickForm::registerElementType('button', "$CFG->libdir/form/button.php", 'MoodleQuickForm_button');
MoodleQuickForm::registerElementType('choosecoursefile', "$CFG->libdir/form/choosecoursefile.php", 'MoodleQuickForm_choosecoursefile');
MoodleQuickForm::registerElementType('choosecoursefileorimsrepo', "$CFG->libdir/form/choosecoursefileorimsrepo.php", 'MoodleQuickForm_choosecoursefileorimsrepo');
MoodleQuickForm::registerElementType('header', "$CFG->libdir/form/header.php", 'MoodleQuickForm_header');
MoodleQuickForm::registerElementType('submit', "$CFG->libdir/form/submit.php", 'MoodleQuickForm_submit');
MoodleQuickForm::registerElementType('questioncategory', "$CFG->libdir/form/questioncategory.php", 'MoodleQuickForm_questioncategory');
MoodleQuickForm::registerElementType('advcheckbox', "$CFG->libdir/form/advcheckbox.php", 'MoodleQuickForm_advcheckbox');
MoodleQuickForm::registerElementType('recaptcha', "$CFG->libdir/form/recaptcha.php", 'MoodleQuickForm_recaptcha');
MoodleQuickForm::registerElementType('selectwithlink', "$CFG->libdir/form/selectwithlink.php", 'MoodleQuickForm_selectwithlink');
?>