HFP-2184 Add utility class for handling metadata

h5p-metadata.class.php

@@ -0,0 +1,84 @@
+<?php
+/**
+ * Utility class for handling metadata
+ */
+abstract class H5PMetadata {
+
+  const FIELDS = array(
+    'authors' => array(
+      'type' => 'json'
+    ),
+    'changes' => array(
+      'type' => 'json'
+    ),
+    'source' => array(
+      'type' => 'text',
+      'maxLength' => 255
+    ),
+    'license' => array(
+      'type' => 'text',
+      'maxLength' => 32
+    ),
+    'licenseVersion' => array(
+      'type' => 'text',
+      'maxLength' => 10
+    ),
+    'licenseExtras' => array(
+      'type' => 'text',
+      'maxLength' => 5000
+    ),
+    'authorComments' => array(
+      'type' => 'text',
+      'maxLength' => 5000
+    ),
+    'yearFrom' => array(
+      'type' => 'int'
+    ),
+    'yearTo' => array(
+      'type' => 'int'
+    )
+  );
+
+  /**
+   * Make the metadata into an associative array keyed by the property names
+   * @param mixed $metadata Array or object containing metadata
+   * @return array
+   */
+  public static function toDBArray($metadata, &$types = array()) {
+    $fields = array();
+
+    if (!is_array($metadata)) {
+      $metadata = (array) $metadata;
+    }
+
+    foreach (self::FIELDS as $key => $config) {
+      if (isset($metadata[$key])) {
+        $value = $metadata[$key];
+        $db_field_name = strtolower(preg_replace('/(?<!^)[A-Z]/', '_$0', $key));
+
+        switch ($config['type']) {
+          case 'text':
+            if (strlen($value) > $config['maxLength']) {
+              $value = mb_substr($value, 0, $config['maxLength']);
+            }
+            $types[] = '%s';
+            break;
+
+          case 'int':
+            $value = ($value !== null) ? intval($value): null;
+            $types[] = '%i';
+            break;
+
+          case 'json':
+            $value = json_encode($value);
+            $types[] = '%s';
+            break;
+        }
+
+        $fields[$db_field_name] = $value;
+      }
+    }
+
+    return $fields;
+  }
+}