MDL-75234 mod_data: load default templates when empty

The mod_data is forcing teachers to understand how to write templates
even if they want to use basic forms. With this patch the default
templates will be auto updated unless the user manually define the
templates.

mod/data/classes/template.php

@@ -168,6 +168,15 @@ class template {
         ];
     }
 
+    /**
+     * Return the raw template content.
+     *
+     * @return string the template content before parsing
+     */
+    public function get_template_content(): string {
+        return $this->templatecontent;
+    }
+
     /**
      * Return the parsed entry using a template.
      *
@@ -736,4 +745,71 @@ class template {
 
         return $OUTPUT->render($actionmenu);
     }
+
+    /**
+     * Parse the template as if it was for add entry.
+     *
+     * This method is similar to the parse_entry but it uses the display_add_field method
+     * instead of the display_browse_field.
+     *
+     * @param stdClass|null $processeddata the previous process data information.
+     * @param int|null $entryid the possible entry id
+     * @param stdClass|null $entrydata the entry data from a previous form or from a real entry
+     * @return string the add entry HTML content
+     */
+    public function parse_add_entry(
+        ?stdClass $processeddata = null,
+        ?int $entryid = null,
+        ?stdClass $entrydata = null
+    ): string {
+        $manager = $this->manager;
+        $renderer = $manager->get_renderer();
+        $templatecontent = $this->templatecontent;
+
+        if (!$processeddata) {
+            $processeddata = (object)[
+                'generalnotifications' => [],
+                'fieldnotifications' => [],
+            ];
+        }
+
+        $result = '';
+
+        foreach ($processeddata->generalnotifications as $notification) {
+            $result .= $renderer->notification($notification);
+        }
+
+        $possiblefields = $manager->get_fields();
+        $patterns = [];
+        $replacements = [];
+
+        // Then we generate strings to replace.
+        foreach ($possiblefields as $field) {
+            // To skip unnecessary calls to display_add_field().
+            if (strpos($templatecontent, "[[" . $field->field->name . "]]") !== false) {
+                // Replace the field tag.
+                $patterns[] = "[[" . $field->field->name . "]]";
+                $errors = '';
+                $fieldnotifications = $processeddata->fieldnotifications[$field->field->name] ?? [];
+                if (!empty($fieldnotifications)) {
+                    foreach ($fieldnotifications as $notification) {
+                        $errors .= $renderer->notification($notification);
+                    }
+                }
+                $replacements[] = $errors . $field->display_add_field($entryid, $entrydata);
+            }
+
+            // Replace the field id tag.
+            $patterns[] = "[[" . $field->field->name . "#id]]";
+            $replacements[] = 'field_' . $field->field->id;
+        }
+
+        if (core_tag_tag::is_enabled('mod_data', 'data_records')) {
+            $patterns[] = "##tags##";
+            $replacements[] = data_generate_tag_form($entryid);
+        }
+
+        $result .= str_ireplace($patterns, $replacements, $templatecontent);
+        return $result;
+    }
 }