Handle deleting stack questions

... and moving them between contexts.

edit_stack_form.php

@@ -349,7 +349,7 @@ class qtype_stack_edit_form extends question_edit_form {
         $question->{$prtname . 'testoptions'}[$nodename] = $node->testoptions;
         $question->{$prtname . 'quiet'      }[$nodename] = $node->quiet;
 
-        // 0 + bit is to change strings like 1.0000000 from the DB to the nicer 1.
+        // 0 + bit is to eliminate excessive decimal places from the DB.
         $question->{$prtname . 'truescoremode' }[$nodename] = $node->truescoremode;
         $question->{$prtname . 'truescore'     }[$nodename] = 0 + $node->truescore;
         $question->{$prtname . 'truepenalty'   }[$nodename] = 0 + $node->truepenalty;
@@ -357,7 +357,7 @@ class qtype_stack_edit_form extends question_edit_form {
         $question->{$prtname . 'trueanswernote'}[$nodename] = $node->trueanswernote;
         $question->{$prtname . 'truefeedback'  }[$nodename] = $this->prepare_text_field(
                 $prtname . 'truefeedback[' . $nodename . ']', $node->truefeedback,
-                $node->truefeedbackformat, $node->id);
+                $node->truefeedbackformat, $node->id, 'prtnodetruefeedback');
 
         $question->{$prtname . 'falsescoremode' }[$nodename] = $node->falsescoremode;
         $question->{$prtname . 'falsescore'     }[$nodename] = 0 + $node->falsescore;
@@ -366,7 +366,7 @@ class qtype_stack_edit_form extends question_edit_form {
         $question->{$prtname . 'falseanswernote'}[$nodename] = $node->falseanswernote;
         $question->{$prtname . 'falsefeedback'  }[$nodename] = $this->prepare_text_field(
                 $prtname . 'falsefeedback[' . $nodename . ']', $node->falsefeedback,
-                $node->falsefeedbackformat, $node->id);
+                $node->falsefeedbackformat, $node->id, 'prtnodefalsefeedback');
 
         return $question;
     }
@@ -377,13 +377,18 @@ class qtype_stack_edit_form extends question_edit_form {
      * @param string $text the raw text contents of this field.
      * @param int $format the text format (one of the FORMAT_... constants.)
      * @param int $itemid file area itemid.
+     * @param string $filearea the file area name. Defaults to $field.
      * @return array in the format needed by the form.
      */
-    protected function prepare_text_field($field, $text, $format, $itemid) {
+    protected function prepare_text_field($field, $text, $format, $itemid, $filearea = '') {
+        if ($filearea === '') {
+            $filearea = $field;
+        }
+
         $data = array();
         $data['itemid'] = file_get_submitted_draft_itemid($field);
         $data['text'] = file_prepare_draft_area($data['itemid'], $this->context->id,
-                'qtype_stack', $field, $itemid, $this->fileoptions, $text);
+                'qtype_stack', $filearea, $itemid, $this->fileoptions, $text);
         $data['format'] = $format;
         return $data;
     }

questiontype.php

@@ -286,4 +286,57 @@ class qtype_stack extends question_type {
                     $feedbackvariables->get_session(), $nodes);
         }
     }
+
+    public function delete_question($questionid, $contextid) {
+        global $DB;
+        $DB->delete_records('qtype_stack_prt_nodes', array('questionid' => $questionid));
+        $DB->delete_records('qtype_stack_prts',      array('questionid' => $questionid));
+        $DB->delete_records('qtype_stack_inputs',    array('questionid' => $questionid));
+        $DB->delete_records('qtype_stack',           array('questionid' => $questionid));
+        parent::delete_question($questionid, $contextid);
+    }
+
+    public function move_files($questionid, $oldcontextid, $newcontextid) {
+        global $DB;
+        $fs = get_file_storage();
+
+        parent::move_files($questionid, $oldcontextid, $newcontextid);
+
+        $fs->move_area_files_to_new_context($oldcontextid, $newcontextid,
+                                            'qtype_stack', 'specificfeedback',    $questionid);
+        $fs->move_area_files_to_new_context($oldcontextid, $newcontextid,
+                                            'qtype_stack', 'prtcorrect',          $questionid);
+        $fs->move_area_files_to_new_context($oldcontextid, $newcontextid,
+                                            'qtype_stack', 'prtpartiallycorrect', $questionid);
+        $fs->move_area_files_to_new_context($oldcontextid, $newcontextid,
+                                            'qtype_stack', 'prtincorrect',        $questionid);
+
+        $nodeids = $DB->get_records_menu('qtype_stack_prt_nodes', array('questionid' => $questionid), 'id', 'id,1');
+        foreach ($nodeids as $nodeid => $notused) {
+            $fs->move_area_files_to_new_context($oldcontextid, $newcontextid,
+                                                'qtype_stack', 'prtnodetruefeedback', $nodeid);
+            $fs->move_area_files_to_new_context($oldcontextid, $newcontextid,
+                                                'qtype_stack', 'prtnodefalsefeedback', $nodeid);
+        }
+    }
+
+    protected function delete_files($questionid, $contextid) {
+        global $DB;
+        $fs = get_file_storage();
+
+        parent::delete_files($questionid, $contextid);
+
+        $fs->delete_area_files($contextid, 'qtype_stack', 'specificfeedback',    $questionid);
+        $fs->delete_area_files($contextid, 'qtype_stack', 'prtcorrect',          $questionid);
+        $fs->delete_area_files($contextid, 'qtype_stack', 'prtpartiallycorrect', $questionid);
+        $fs->delete_area_files($contextid, 'qtype_stack', 'prtincorrect',        $questionid);
+
+        $nodeids = $DB->get_records_menu('qtype_stack_prt_nodes', array('questionid' => $questionid), 'id', 'id,1');
+        foreach ($nodeids as $nodeid => $notused) {
+            $fs->delete_area_files($oldcontextid, $newcontextid,
+                                                'qtype_stack', 'prtnodetruefeedback', $nodeid);
+            $fs->delete_area_files($oldcontextid, $newcontextid,
+                                                'qtype_stack', 'prtnodefalsefeedback', $nodeid);
+        }
+    }
 }