Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * autocomplete type form element

 *

 * Contains HTML class for a autocomplete type element

 *

 * @package   core_form

 * @copyright 2015 Damyon Wiese <damyon@moodle.com>

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

global $CFG;

require_once($CFG->libdir . '/form/select.php');

/**

 * Autocomplete as you type form element

 *

 * HTML class for a autocomplete type element

 *

 * @package   core_form

 * @copyright 2015 Damyon Wiese <damyon@moodle.com>

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class MoodleQuickForm_autocomplete extends MoodleQuickForm_select {

    /** @var boolean $tags Should we allow typing new entries to the field? */

    protected $tags = false;

    /** @var string $ajax Name of an AMD module to send/process ajax requests. */

    protected $ajax = '';

    /** @var string $placeholder Placeholder text for an empty list. */

    protected $placeholder = '';

    /** @var bool $casesensitive Whether the search has to be case-sensitive. */

    protected $casesensitive = false;

    /** @var bool $showsuggestions Show suggestions by default - but this can be turned off. */

    protected $showsuggestions = true;

    /** @var string $noselectionstring String that is shown when there are no selections. */

    protected $noselectionstring = '';

    /** @var callable|null Function to call (with existing value) to render it to HTML */

    protected $valuehtmlcallback = null;

    /**

     * constructor

     *

     * @param string $elementName Select name attribute

     * @param mixed $elementLabel Label(s) for the select

     * @param mixed $options Data to be used to populate options

     * @param mixed $attributes Either a typical HTML attribute string or an associative array. Special options

     *                          "tags", "placeholder", "ajax", "multiple", "casesensitive" are supported.

     */

    public function __construct($elementName=null, $elementLabel=null, $options=null, $attributes=null) {

        // Even if the constructor gets called twice we do not really want 2x options (crazy forms!).

        $this->_options = array();

        if ($attributes === null) {

            $attributes = array();

        }

        if (isset($attributes['tags'])) {

            $this->tags = $attributes['tags'];

            unset($attributes['tags']);

        }

        if (isset($attributes['showsuggestions'])) {

            $this->showsuggestions = $attributes['showsuggestions'];

            unset($attributes['showsuggestions']);

        }

        $this->placeholder = get_string('search');

        if (isset($attributes['placeholder'])) {

            $this->placeholder = $attributes['placeholder'];

            unset($attributes['placeholder']);

        }

        $this->noselectionstring = get_string('noselection', 'form');

        if (isset($attributes['noselectionstring'])) {

            $this->noselectionstring = $attributes['noselectionstring'];

            unset($attributes['noselectionstring']);

        }

        if (isset($attributes['ajax'])) {

            $this->ajax = $attributes['ajax'];

            unset($attributes['ajax']);

        }

        if (isset($attributes['casesensitive'])) {

            $this->casesensitive = $attributes['casesensitive'] ? true : false;

            unset($attributes['casesensitive']);

        }

        if (isset($attributes['valuehtmlcallback'])) {

            $this->valuehtmlcallback = $attributes['valuehtmlcallback'];

            unset($attributes['valuehtmlcallback']);

        }

        parent::__construct($elementName, $elementLabel, $options, $attributes);

        $this->_type = 'autocomplete';

    }

    /**

     * Old syntax of class constructor. Deprecated in PHP7.

     *

     * @deprecated since Moodle 3.1

     */

    public function MoodleQuickForm_autocomplete($elementName=null, $elementLabel=null, $options=null, $attributes=null) {

        debugging('Use of class name as constructor is deprecated', DEBUG_DEVELOPER);

        self::__construct($elementName, $elementLabel, $options, $attributes);

    }

    /**

     * Returns HTML for select form element.

     *

     * @return string

     */

    function toHtml(){

        global $PAGE;

        // Enhance the select with javascript.

        $this->_generateId();

        $id = $this->getAttribute('id');

        if (!$this->isFrozen()) {

            $PAGE->requires->js_call_amd('core/form-autocomplete', 'enhance', $params = array('#' . $id, $this->tags, $this->ajax,

                $this->placeholder, $this->casesensitive, $this->showsuggestions, $this->noselectionstring));

        }

        $html = parent::toHTML();

        // Hacky bodge to add in the HTML code to the option tag. There is a nicer

        // version of this code in the new template version (see export_for_template).

        if ($this->valuehtmlcallback) {

            $html = preg_replace_callback('~value="([^"]+)"~', function($matches) {

                $value = html_entity_decode($matches[1], ENT_COMPAT);

                $htmlvalue = call_user_func($this->valuehtmlcallback, $value);

                if ($htmlvalue !== false) {

                    return $matches[0] . ' data-html="' . s($htmlvalue) . '"';

                } else {

                    return $matches[0];

                }

            }, $html);

        }

        return $html;

    }

    /**

     * Search the current list of options to see if there are any options with this value.

     * @param  string $value to search

     * @return boolean

     */

    function optionExists($value) {

        foreach ($this->_options as $option) {

            if (isset($option['attr']['value']) && ($option['attr']['value'] == $value)) {

                return true;

            }

        }

        return false;

    }

    /**

     * Set the value of this element. If values can be added or are unknown, we will

     * make sure they exist in the options array.

     * @param  mixed string|array $value The value to set.

     * @return boolean

     */

    function setValue($value) {

        $values = (array) $value;

        foreach ($values as $onevalue) {

            if (($this->tags || $this->ajax) &&

                    (!$this->optionExists($onevalue)) &&

                    ($onevalue !== '_qf__force_multiselect_submission')) {

                $this->addOption($onevalue, $onevalue);

            }

        }

        return parent::setValue($value);

    }

    /**

     * Returns a 'safe' element's value

     *

     * @param  array   array of submitted values to search

     * @param  bool    whether to return the value as associative array

     * @access public

     * @return mixed

     */

    function exportValue(&$submitValues, $assoc = false) {

        if ($this->ajax || $this->tags) {

            // When this was an ajax request, we do not know the allowed list of values.

            $value = $this->_findValue($submitValues);

            if (null === $value) {

                $value = $this->getValue();

            }

            // Quickforms inserts a duplicate element in the form with

            // this value so that a value is always submitted for this form element.

            // Normally this is cleaned as a side effect of it not being a valid option,

            // but in this case we need to detect and skip it manually.

            if ($value === '_qf__force_multiselect_submission' || $value === null) {

                $value = $this->getMultiple() ? [] : '';

            }

            return $this->_prepareValue($value, $assoc);

        } else {

            return parent::exportValue($submitValues, $assoc);

        }

    }

    /**

     * Called by HTML_QuickForm whenever form event is made on this element

     *

     * @param string $event Name of event

     * @param mixed $arg event arguments

     * @param object $caller calling object

     * @return bool

     */

    function onQuickFormEvent($event, $arg, &$caller)

    {

        switch ($event) {

            case 'createElement':

                $caller->setType($arg[0], PARAM_TAGLIST);

                break;

        }

        return parent::onQuickFormEvent($event, $arg, $caller);

    }

    public function export_for_template(renderer_base $output) {

        $this->_generateId();

        $context = parent::export_for_template($output);

        $context['tags'] = !empty($this->tags);

        $context['ajax'] = $this->ajax;

        $context['placeholder'] = $this->placeholder;

        $context['casesensitive'] = !empty($this->casesensitive);

        $context['showsuggestions'] = !empty($this->showsuggestions);

        $context['noselectionstring'] = $this->noselectionstring;

        if ($this->valuehtmlcallback) {

            foreach ($context['options'] as &$option) {

                $value = $option['value'];

                $html = call_user_func($this->valuehtmlcallback, $value);

                if ($html !== false) {

                    $option['html'] = $html;

                    if ($this->isFrozen()) {

                        $option['text'] = $html;

                    }

                }

            }

        }

        return $context;

    }

}