MDL-53240 filetypes: Introduce the form element to specify plugin types

This is a stripped down version of the original Jonathon's element
without the actual JS selector. The options "allowall" and "onlytypes"
are not fully supported right now yet.

lib/form/filetypes.php

@@ -0,0 +1,194 @@
+<?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/>.
+
+/**
+ * Provides the {@link MoodleQuickForm_filetypes} class.
+ *
+ * @package   core_form
+ * @copyright 2016 Jonathon Fowler <fowlerj@usq.edu.au>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+use core_form\filetypes_util;
+
+defined('MOODLE_INTERNAL') || die;
+
+global $CFG;
+require_once($CFG->dirroot.'/lib/form/group.php');
+
+/**
+ * File types and type groups selection form element.
+ *
+ * @package   core_form
+ * @category  form
+ * @copyright 2016 Jonathon Fowler <fowlerj@usq.edu.au>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class MoodleQuickForm_filetypes extends MoodleQuickForm_group {
+
+    /** @var array Allow selection from these file types only. */
+    protected $onlytypes = [];
+
+    /** @var bool Allow selection of 'All file types' (will be stored as '*'). */
+    protected $allowall = true;
+
+    /** @var core_form\filetypes_util instance to use as a helper. */
+    protected $util = null;
+
+    /**
+     * Constructor
+     *
+     * @param string $elementName Element's name
+     * @param string $elementLabel Label(s) for an element
+     * @param array $options element options:
+     *   'onlytypes': Allow selection from these file types only; for example ['onlytypes' => ['web_image']].
+     *   'allowall': Allow to select 'All file types', defaults to true. Does not apply with onlytypes are set.
+     * @param array|string $attributes Either a typical HTML attribute string or an associative array
+     */
+    public function __construct($elementName = null, $elementLabel = null, $options = null, $attributes = null) {
+
+        parent::__construct($elementName, $elementLabel);
+        $this->_type = 'filetypes';
+
+        // Hard-frozen elements do not get the name populated automatically,
+        // which leads to PHP notice. Add it explicitly here.
+        $this->setAttributes(array('name' => $elementName));
+        $this->updateAttributes($attributes);
+
+        if (is_array($options) && $options) {
+            if (array_key_exists('onlytypes', $options) && is_array($options['onlytypes'])) {
+                $this->onlytypes = $options['onlytypes'];
+            }
+            if (!$this->onlytypes && array_key_exists('allowall', $options)) {
+                $this->allowall = (bool)$options['allowall'];
+            }
+        }
+
+        $this->util = new filetypes_util();
+    }
+
+    /**
+     * Assemble the elements of the form control.
+     */
+    public function _createElements() {
+
+        $this->_generateId();
+
+        $this->setElements([
+            $this->createFormElement('text', 'filetypes', '', [
+                'id' => $this->getAttribute('id'),
+            ]),
+
+            $this->createFormElement('static', 'browser', null,
+                '<span data-filetypesbrowser="'.$this->getAttribute('id').'"></span>'),
+
+            $this->createFormElement('static', 'descriptions'),
+        ]);
+    }
+
+    /**
+     * Return the selected file types.
+     *
+     * @param array $submitValues submitted values
+     * @param bool $assoc if true the retured value is associated array
+     * @return array
+     */
+    public function exportValue(&$submitValues, $assoc = false) {
+
+        $value = '';
+        $filetypeselement = null;
+
+        foreach ($this->_elements as $key => $element) {
+            if ($element->_attributes['name'] === 'filetypes') {
+                $filetypeselement = $this->_elements[$key];
+            }
+        }
+
+        if ($filetypeselement) {
+            $formval = $filetypeselement->exportValue($submitValues[$this->getName()], false);
+            if ($formval) {
+                $value = $this->util->normalize_file_types($formval);
+                if ($value === ['*'] && !$this->allowall) {
+                    $value = [];
+                }
+                $value = implode(',', $value);
+            }
+        }
+
+        return $this->_prepareValue($value, $assoc);
+    }
+
+    /**
+     * Accepts a renderer (called shortly before the renderer's toHtml() method).
+     *
+     * @param HTML_QuickForm_Renderer $renderer An HTML_QuickForm_Renderer object
+     * @param bool $required Whether a group is required
+     * @param string $error An error message associated with a group
+     */
+    public function accept(&$renderer, $required = false, $error = null) {
+        global $PAGE;
+
+        if ($this->isFrozen()) {
+            // Don't render the choose button if the control is frozen.
+            foreach ($this->_elements as $key => $element) {
+                if ($element->_attributes['name'] === 'browser') {
+                    unset($this->_elements[$key]);
+                }
+            }
+        }
+
+        parent::accept($renderer, $required, $error);
+    }
+
+    /**
+     * 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 $caller calling object
+     * @return bool
+     */
+    public function onQuickFormEvent($event, $arg, &$caller) {
+        global $OUTPUT;
+
+        switch ($event) {
+            case 'updateValue':
+                $value = $this->_findValue($caller->_constantValues);
+                if (null === $value) {
+                    if ($caller->isSubmitted()) {
+                        $value = $this->_findValue($caller->_submitValues);
+                    } else {
+                        $value = (string)$this->_findValue($caller->_defaultValues);
+                    }
+                }
+                if (!is_array($value)) {
+                    $value = array('filetypes' => $value);
+                }
+                if ($value['filetypes'] !== null) {
+                    $filetypes = $this->util->normalize_file_types($value['filetypes']);
+					if ($filetypes === ['*'] && !$this->allowall) {
+						$filetypes = [];
+					}
+                    $value['descriptions'] = $OUTPUT->render_from_template('core_form/filetypes-descriptions',
+                        $this->util->describe_file_types($filetypes));
+                }
+                $this->setValue($value);
+                return true;
+        }
+
+        return parent::onQuickFormEvent($event, $arg, $caller);
+    }
+}

lib/form/templates/filetypes-descriptions.mustache

@@ -0,0 +1,60 @@
+{{!
+    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/>.
+}}
+{{!
+    @template core_form/filetypes-descriptions
+
+    Template to describe chosen file types.
+
+    Classes required for JS:
+    * none
+
+    Data attributes required for JS:
+    * none
+
+    Context variables required for this template:
+    * hasdescriptions (bool)
+    * descriptions (array)
+        * description (string)
+        * extensions (string)
+
+    Example context (json):
+    {
+        "hasdescriptions": true,
+        "descriptions": [
+            {
+                "description": "Image (JPEG)",
+                "extensions": ".jpeg .jpe .jpg"
+            },
+            {
+                "description": "Image (GIF)",
+                "extensions": ".gif"
+            }
+        ]
+    }
+}}
+<div class="form-filetypes-descriptions">
+{{#hasdescriptions}}
+    <ul class="list-unstyled unstyled">
+        {{#descriptions}}
+        <li>{{description}} <small class="text-muted muted">{{extensions}}</small></li>
+        {{/descriptions}}
+    </ul>
+{{/hasdescriptions}}
+{{^hasdescriptions}}
+    <p>{{#str}}noselection, form{{/str}}</p>
+{{/hasdescriptions}}
+</div>

lib/formslib.php

@@ -3105,6 +3105,7 @@ MoodleQuickForm::registerElementType('duration', "$CFG->libdir/form/duration.php
 MoodleQuickForm::registerElementType('editor', "$CFG->libdir/form/editor.php", 'MoodleQuickForm_editor');
 MoodleQuickForm::registerElementType('filemanager', "$CFG->libdir/form/filemanager.php", 'MoodleQuickForm_filemanager');
 MoodleQuickForm::registerElementType('filepicker', "$CFG->libdir/form/filepicker.php", 'MoodleQuickForm_filepicker');
+MoodleQuickForm::registerElementType('filetypes', "$CFG->libdir/form/filetypes.php", 'MoodleQuickForm_filetypes');
 MoodleQuickForm::registerElementType('grading', "$CFG->libdir/form/grading.php", 'MoodleQuickForm_grading');
 MoodleQuickForm::registerElementType('group', "$CFG->libdir/form/group.php", 'MoodleQuickForm_group');
 MoodleQuickForm::registerElementType('header', "$CFG->libdir/form/header.php", 'MoodleQuickForm_header');

theme/boost/templates/core_form/element-filetypes.mustache

@@ -0,0 +1 @@
+{{> core_form/element-group }}