MDL-51739 theme: allow config to lock theme selector

If any of the devices have their theme set in config.php
it will lock the theme selector UI from being able to change
the theme.

diff --git a/lib/outputlib.php b/lib/outputlib.php
index 87e5c73..e1ada8a 100644 (file)
--- a/lib/outputlib.php
+++ b/lib/outputlib.php
@@ -96,6 +96,32 @@ function theme_get_revision() {
     }
 }
 
+/**
+ * Checks if the given device has a theme defined in config.php.
+ *
+ * @return bool
+ */
+function theme_is_device_locked($device) {
+    global $CFG;
+    $themeconfigname = core_useragent::get_device_type_cfg_var_name($device);
+    return isset($CFG->config_php_settings[$themeconfigname]);
+}
+
+/**
+ * Returns the theme named defined in config.php for the given device.
+ *
+ * @return string or null
+ */
+function theme_get_locked_theme_for_device($device) {
+    global $CFG;
+
+    if (!theme_is_device_locked($device)) {
+        return null;
+    }
+
+    $themeconfigname = core_useragent::get_device_type_cfg_var_name($device);
+    return $CFG->config_php_settings[$themeconfigname];
+}
 
 /**
  * This class represents the configuration variables of a Moodle theme.

diff --git a/theme/index.php b/theme/index.php
index 1dbeded..788e3e8 100644 (file)
--- a/theme/index.php
+++ b/theme/index.php
@@ -45,9 +45,10 @@ unset($SESSION->theme);
 if ($reset and confirm_sesskey()) {
     theme_reset_all_caches();
 
-} else if ($choose && $device && !$unsettheme && confirm_sesskey()) {
+} else if ($choose && $device && !theme_is_device_locked($device) && !$unsettheme && confirm_sesskey()) {
     // Load the theme to make sure it is valid.
     $theme = theme_config::load($choose);
+
     // Get the config argument for the chosen device.
     $themename = core_useragent::get_device_type_cfg_var_name($device);
     set_config($themename, $theme->name);
@@ -73,7 +74,7 @@ if ($reset and confirm_sesskey()) {
     echo $output->continue_button($CFG->wwwroot . '/theme/index.php');
     echo $output->footer();
     exit;
-} else if ($device && $unsettheme && confirm_sesskey() && ($device != 'default')) {
+} else if ($device && !theme_is_device_locked($device) && $unsettheme && confirm_sesskey() && ($device != 'default')) {
     // Unset the theme and continue.
     unset_config(core_useragent::get_device_type_cfg_var_name($device));
     $device = '';
@@ -104,6 +105,7 @@ if (!empty($CFG->enabledevicedetection) && empty($device)) {
         if (!$themename && $thedevice == 'default') {
             $themename = theme_config::DEFAULT_THEME;
         }
+        $themelocked = theme_is_device_locked($thedevice);
 
         $screenshotcell = $strthemenotselected;
         $unsetthemebutton = '';
@@ -125,7 +127,7 @@ if (!empty($CFG->enabledevicedetection) && empty($device)) {
                 $headingthemename = $OUTPUT->heading($strthemename, 3);
             }
             // If not default device then show option to unset theme.
-            if ($thedevice != 'default') {
+            if ($thedevice != 'default' && !$themelocked) {
                 $unsetthemestr = get_string('unsettheme', 'admin');
                 $unsetthemeurl = new moodle_url('/theme/index.php',
                     array('device' => $thedevice, 'sesskey' => sesskey(), 'unsettheme' => true));
@@ -135,12 +137,21 @@ if (!empty($CFG->enabledevicedetection) && empty($device)) {
         }
 
         $deviceurl = new moodle_url('/theme/index.php', array('device' => $thedevice, 'sesskey' => sesskey()));
-        $select = new single_button($deviceurl, $strthemeselect, 'get');
+
+        $select = '';
+        if (!$themelocked) {
+            $select = $OUTPUT->render(new single_button($deviceurl, $strthemeselect, 'get'));
+        }
+
+        $lockwarning = '';
+        if ($themelocked) {
+            $lockwarning = html_writer::div(get_string('configoverride', 'admin'), 'alert alert-info');
+        }
 
         $table->data[] = array(
             $OUTPUT->heading(ucfirst($thedevice), 3),
             $screenshotcell,
-            $headingthemename . $OUTPUT->render($select) . $unsetthemebutton
+            $headingthemename . $lockwarning . $select . $unsetthemebutton
         );
     }
 } else {
@@ -152,10 +163,19 @@ if (!empty($CFG->enabledevicedetection) && empty($device)) {
         $device = core_useragent::get_device_type();
     }
 
+    $themelocked = theme_is_device_locked($device);
     $table->id = 'adminthemeselector';
     $table->head = array(get_string('theme'), get_string('info'));
 
-    $themes = core_component::get_plugin_list('theme');
+    $themes = array();
+    if ($themelocked) {
+        $heading = get_string('currenttheme', 'admin');
+        $themename = theme_get_locked_theme_for_device($device);
+        $themedirectory = core_component::get_plugin_directory('theme', $themename);
+        $themes[$themename] = $themedirectory;
+    } else {
+        $themes = core_component::get_plugin_list('theme');
+    }
 
     foreach ($themes as $themename => $themedir) {
 
@@ -199,19 +219,25 @@ if (!empty($CFG->enabledevicedetection) && empty($device)) {
         // Contents of the second cell.
         $infocell = $OUTPUT->heading($strthemename, 3);
 
+        if ($themelocked) {
+            $infocell .= html_writer::div(get_string('configoverride', 'admin'), 'alert alert-info');
+        }
+
         // Button to choose this as the main theme or unset this theme for devices other then default.
-        if (($ischosentheme) && ($device != 'default')) {
-            $unsetthemestr = get_string('unsettheme', 'admin');
-            $unsetthemeurl = new moodle_url('/theme/index.php',
-                array('device' => $device, 'unsettheme' => true, 'sesskey' => sesskey()));
-            $unsetbutton = new single_button($unsetthemeurl, $unsetthemestr, 'get');
-            $infocell .= $OUTPUT->render($unsetbutton);
-        } else if ((!$ischosentheme)) {
-            $setthemestr = get_string('usetheme');
-            $setthemeurl = new moodle_url('/theme/index.php',
-                array('device' => $device, 'choose' => $themename, 'sesskey' => sesskey()));
-            $setthemebutton = new single_button($setthemeurl, $setthemestr, 'get');
-            $infocell .= $OUTPUT->render($setthemebutton);
+        if (!$themelocked) {
+            if (($ischosentheme) && ($device != 'default')) {
+                $unsetthemestr = get_string('unsettheme', 'admin');
+                $unsetthemeurl = new moodle_url('/theme/index.php',
+                    array('device' => $device, 'unsettheme' => true, 'sesskey' => sesskey()));
+                $unsetbutton = new single_button($unsetthemeurl, $unsetthemestr, 'get');
+                $infocell .= $OUTPUT->render($unsetbutton);
+            } else if ((!$ischosentheme)) {
+                $setthemestr = get_string('usetheme');
+                $setthemeurl = new moodle_url('/theme/index.php',
+                    array('device' => $device, 'choose' => $themename, 'sesskey' => sesskey()));
+                $setthemebutton = new single_button($setthemeurl, $setthemestr, 'get');
+                $infocell .= $OUTPUT->render($setthemebutton);
+            }
         }
 
         $row[] = $infocell;