MDL-62387 tool_lp: switch to core 'cohort' form element.

The autocomplete AJAX is identical to the version in tool_lp, but also
includes support for excluding suggestions (i.e. cohorts already
synced with the current learning plan).

admin/tool/lp/classes/form/template_cohorts.php

@@ -26,7 +26,6 @@ namespace tool_lp\form;
 defined('MOODLE_INTERNAL') || die();
 
 use moodleform;
-use core\form\persistent;
 
 require_once($CFG->libdir . '/formslib.php');
 
@@ -39,17 +38,20 @@ require_once($CFG->libdir . '/formslib.php');
  */
 class template_cohorts extends moodleform {
 
+    /**
+     * Form definition
+     *
+     * @return void
+     */
     public function definition() {
         $mform = $this->_form;
 
         $options = array(
-            'ajax' => 'tool_lp/form-cohort-selector',
             'multiple' => true,
-            'data-contextid' => $this->_customdata['pagecontextid'],
-            'data-includes' => 'parents'
+            'exclude' => implode(',', $this->_customdata['excludecohorts']),
+            'contextid' => $this->_customdata['pagecontextid'],
         );
-        $mform->addElement('autocomplete', 'cohorts', get_string('selectcohortstosync', 'tool_lp'), array(), $options);
+        $mform->addElement('cohort', 'cohorts', get_string('selectcohortstosync', 'tool_lp'), $options);
         $mform->addElement('submit', 'submit', get_string('addcohorts', 'tool_lp'));
     }
-
 }

admin/tool/lp/template_cohorts.php

@@ -54,7 +54,19 @@ if ($canmanagetemplate && ($removecohort = optional_param('removecohort', false,
 }
 
 // Capture the form submission.
-$form = new \tool_lp\form\template_cohorts($url->out(false), array('pagecontextid' => $pagecontextid));
+$existingcohortsql =
+    'SELECT c.id
+       FROM {' . \core_competency\template_cohort::TABLE . '} tc
+       JOIN {cohort} c ON c.id = tc.cohortid
+      WHERE tc.templateid = :templateid';
+
+$existingcohorts = $DB->get_records_sql_menu($existingcohortsql, ['templateid' => $template->get('id')]);
+
+$form = new \tool_lp\form\template_cohorts($url->out(false), [
+    'pagecontextid' => $pagecontextid,
+    'excludecohorts' => array_keys($existingcohorts),
+]);
+
 if ($canmanagetemplate && ($data = $form->get_data()) && !empty($data->cohorts)) {
     $maxtocreate = 50;
     $maxreached = false;