From 63c102e0959abfbc2c33550ff02755c01ef7d0de Mon Sep 17 00:00:00 2001
From: Marina Glancy <marina@moodle.com>
Date: Tue, 7 Feb 2017 09:35:46 +0800
Subject: [PATCH] MDL-57316 media: create different instances for different
 pages

---
 lib/tests/medialib_test.php | 20 +++++++++++++++++++-
 media/classes/manager.php   | 20 +++++++++++---------
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/lib/tests/medialib_test.php b/lib/tests/medialib_test.php
index 1710863eaf7..643ed07f90d 100644
--- a/lib/tests/medialib_test.php
+++ b/lib/tests/medialib_test.php
@@ -457,6 +457,23 @@ class core_medialib_testcase extends advanced_testcase {
         $this->assertContains('<source src="http://example.org/test.webm"', $t);
         $this->assertNotContains('<source src="http://example.org/test.flv"', $t);
     }
+
+    /**
+     * Make sure the instance() method returns singleton for the same page and different object for another page
+     */
+    public function test_initialise() {
+        $moodlepage1 = new moodle_page();
+
+        $mediamanager1 = core_media_manager::instance($moodlepage1);
+        $mediamanager2 = core_media_manager::instance($moodlepage1);
+
+        $this->assertSame($mediamanager1, $mediamanager2);
+
+        $moodlepage3 = new moodle_page();
+        $mediamanager3 = core_media_manager::instance($moodlepage3);
+
+        $this->assertNotSame($mediamanager1, $mediamanager3);
+    }
 }
 
 /**
@@ -522,6 +539,7 @@ class core_media_manager_test extends core_media_manager {
      * Override the constructor to access it.
      */
     public function __construct() {
-        parent::__construct();
+        global $PAGE;
+        parent::__construct($PAGE);
     }
 }
diff --git a/media/classes/manager.php b/media/classes/manager.php
index a6effc00d8f..1d23ecb6ab8 100644
--- a/media/classes/manager.php
+++ b/media/classes/manager.php
@@ -97,6 +97,9 @@ class core_media_manager {
     /** @var core_media_manager caches a singleton instance */
     static protected $instance;
 
+    /** @var moodle_page page this instance was initialised for */
+    protected $page;
+
     /**
      * Returns a singleton instance of a manager
      *
@@ -105,7 +108,12 @@ class core_media_manager {
      * @return core_media_manager
      */
     public static function instance($page = null) {
-        if (self::$instance === null) {
+        // Use the passed $page if given, otherwise the $PAGE global.
+        if (!$page) {
+            global $PAGE;
+            $page = $PAGE;
+        }
+        if (self::$instance === null || ($page && self::$instance->page !== $page)) {
             self::$instance = new self($page);
         }
         return self::$instance;
@@ -117,15 +125,9 @@ class core_media_manager {
      * @param moodle_page $page The page we are going to add requirements to.
      * @see core_media_manager::instance()
      */
-    protected function __construct($page = null) {
-        // Use the passed $page if given, otherwise the $PAGE global.
-        if ($page == null) {
-            global $PAGE;
-            if (isset($PAGE)) {
-                $page = $PAGE;
-            }
-        }
+    protected function __construct($page) {
         if ($page) {
+            $this->page = $page;
             $players = $this->get_players();
             foreach ($players as $player) {
                 $player->setup($page);