From 9b96b2c9b338ab2fd3035b1eb625c45c33e0cd29 Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Thu, 27 Apr 2017 21:54:10 +0800
Subject: [PATCH] #102 Handle images during backup/restore

---
 backup/moodle2/backup_customcert_stepslib.php |  4 ++
 .../moodle2/restore_customcert_stepslib.php   | 13 +++++
 element/image/classes/element.php             | 49 +++++++++++++++++++
 3 files changed, 66 insertions(+)

diff --git a/backup/moodle2/backup_customcert_stepslib.php b/backup/moodle2/backup_customcert_stepslib.php
index 8ab6a3b..e720b81 100644
--- a/backup/moodle2/backup_customcert_stepslib.php
+++ b/backup/moodle2/backup_customcert_stepslib.php
@@ -94,6 +94,10 @@ class backup_customcert_activity_structure_step extends backup_activity_structur
         // Annotate the user id's where required.
         $issue->annotate_ids('user', 'userid');
 
+        // Define file annotations.
+        $customcert->annotate_files('mod_customcert', 'intro', null);
+        $customcert->annotate_files('mod_customcert', 'image', null, context_course::instance($this->get_courseid())->id);
+
         // Return the root element (customcert), wrapped into standard activity structure.
         return $this->prepare_activity_structure($customcert);
     }
diff --git a/backup/moodle2/restore_customcert_stepslib.php b/backup/moodle2/restore_customcert_stepslib.php
index 4b3a596..ae9f40d 100644
--- a/backup/moodle2/restore_customcert_stepslib.php
+++ b/backup/moodle2/restore_customcert_stepslib.php
@@ -163,4 +163,17 @@ class restore_customcert_activity_structure_step extends restore_activity_struct
         $newitemid = $DB->insert_record('customcert_issues', $data);
         $this->set_mapping('customcert_issue', $oldid, $newitemid);
     }
+
+    /**
+     * Called immediately after all the other restore functions.
+     */
+    protected function after_execute() {
+        parent::after_execute();
+
+        // Add the files.
+        $this->add_related_files('mod_customcert', 'intro', null);
+
+        // Note - we can't use get_old_contextid() as it refers to the module context.
+        $this->add_related_files('mod_customcert', 'image', null, $this->get_task()->get_info()->original_course_contextid);
+    }
 }
diff --git a/element/image/classes/element.php b/element/image/classes/element.php
index faf3e5b..5ee6871 100644
--- a/element/image/classes/element.php
+++ b/element/image/classes/element.php
@@ -260,6 +260,55 @@ class element extends \mod_customcert\element {
         parent::definition_after_data($mform);
     }
 
+    /**
+     * This function is responsible for handling the restoration process of the element.
+     *
+     * We will want to update the file's pathname hash.
+     *
+     * @param \restore_customcert_activity_task $restore
+     */
+    public function after_restore($restore) {
+        global $DB;
+
+        // Check the files that have been processed in the backup file that belong to the custom certificate activity.
+        if ($files = $DB->get_records('backup_files_temp', array('backupid' => $restore->get_restoreid(),
+                'component' => 'mod_customcert', 'filearea' => 'image'))) {
+            // Get the current data we have stored for this element.
+            $elementinfo = json_decode($this->element->data);
+            // Create a file storage instance we are going to use to create pathname hashes.
+            $fs = get_file_storage();
+            // Loop through each of the files found and compare them with this element.
+            foreach ($files as $file) {
+                if ($fileinfo = \backup_controller_dbops::decode_backup_temp_info($file->info)) {
+                    // Create the array to identify the image by.
+                    $fileidentifier = [
+                        $file->contextid,
+                        'mod_customcert',
+                        'image',
+                        0,
+                        $fileinfo->filepath,
+                        $fileinfo->filename
+                    ];
+                    $pathnamehash = $fs->get_pathname_hash(...$fileidentifier);
+                    // Check if we found the image, if so we need to update the pathname hash.
+                    if ($pathnamehash == $elementinfo->pathnamehash) {
+                        // Change the context id to get the new hash.
+                        $fileidentifier[0] = $file->newcontextid;
+                        $newpathnamehash = $fs->get_pathname_hash(...$fileidentifier);
+
+                        // Save the data now.
+                        $datatosave = new \stdClass();
+                        $datatosave->image = $newpathnamehash;
+                        $datatosave->width = $elementinfo->width;
+                        $datatosave->height = $elementinfo->height;
+                        $DB->set_field('customcert_elements', 'data', self::save_unique_data($datatosave),
+                            array('id' => $this->element->id));
+                    }
+                }
+            }
+        }
+    }
+
     /**
      * Return the list of possible images to use.
      *