Allow blocktypes to implement 'get_instance_title', for which they receive a...

Allow blocktypes to implement 'get_instance_title', for which they receive a blockinstance and can use data from that to set the title of the blockinstance.

For example, the blogpost blocktype can look at the title of the blog post (by examining the configdata for the blogpost id).

htdocs/blocktype/lib.php

@@ -229,16 +229,22 @@ class BlockInstance {
         unset($values['sesskey']);
         unset($values['blockinstance']);
         unset($values['action_configureblockinstance_id_' . $this->get('id')]);
-        $title = $values['title'];
-        unset($values['title']);
 
         if (is_callable(array(generate_class_name('blocktype', $this->get('blocktype')), 'instance_config_save'))) {
             $values = call_static_method(generate_class_name('blocktype', $this->get('blocktype')), 'instance_config_save', $values);
         }
 
-        $configdata = $values;
+        $title = (isset($values['title'])) ? $values['title'] : '';
+        unset($values['title']);
+        $this->set('configdata', $values);
+
+        $blocktypeclass = generate_class_name('blocktype', $this->get('blocktype'));
+        if (method_exists($blocktypeclass, 'get_instance_title')) {
+            // Get the explicitly set instance title
+            $title = call_static_method($blocktypeclass, 'get_instance_title', $this);
+        }
+
         $this->set('title', $title);
-        $this->set('configdata', $configdata);
         $this->commit();
 
         $SESSION->add_ok_msg(get_string('blockinstanceconfiguredsuccessfully', 'view'));
@@ -330,6 +336,14 @@ class BlockInstance {
         $smarty->assign('id',     $this->get('id'));
         $smarty->assign('title',  $this->get('title'));
 
+        // If this block is for just one artefact, we set the title of the 
+        // block to be a link to view more information about that artefact
+        $configdata = $this->get('configdata');
+        if (!empty($configdata['artefactid'])) {
+            $smarty->assign('viewartefacturl', get_config('wwwroot') . 'view/view.php?view='
+                . $this->get('view') . '&artefact=' . $configdata['artefactid']);
+        }
+
         $smarty->assign('content', $content);
         
         return $smarty->fetch('view/blocktypecontainerviewing.tpl');
@@ -343,16 +357,26 @@ class BlockInstance {
      */
     public function build_configure_form() {
         safe_require('blocktype', $this->get('blocktype'));
-        $elements = array_merge(
-            array(
-                'title' => array(
-                    'type' => 'text',
-                    'title' => 'Block Title',
-                    'defaultvalue' => $this->get('title')
+        $elements = call_static_method(generate_class_name('blocktype', $this->get('blocktype')), 'instance_config_form', $this);
+
+        $blocktypeclass = generate_class_name('blocktype', $this->get('blocktype'));
+        if (method_exists($blocktypeclass, 'get_instance_title')) {
+            // Get the explicitly set instance title
+            $title = call_static_method($blocktypeclass, 'get_instance_title', $this);
+        }
+        else {
+            // Use the blocktype title as a default
+            $elements = array_merge(
+                array(
+                    'title' => array(
+                        'type' => 'text',
+                        'title' => 'Block Title',
+                        'defaultvalue' => $this->get('title')
+                    ),
                 ),
-            ),
-            call_static_method(generate_class_name('blocktype', $this->get('blocktype')), 'instance_config_form', $this)
-        );
+                $elements
+            );
+        }
 
         // Add submit/cancel buttons
         $elements['action_configureblockinstance_id_' . $this->get('id')] = array(
@@ -410,7 +434,15 @@ class BlockInstance {
         }
         $fordb = new StdClass;
         foreach (get_object_vars($this) as $k => $v) {
-            $fordb->{$k} = $v;
+            // The configdata is initially fetched from the database in string 
+            // form. Calls to get() will convert it to an array on the fly. We 
+            // ensure that it is a string again here
+            if ($k == 'configdata' && is_array($v)) {
+                $fordb->{$k} = serialize($v);
+            }
+            else {
+                $fordb->{$k} = $v;
+            }
         }
         if (empty($this->id)) {
             $this->id = insert_record('block_instance', $fordb, 'id', true);