OGPからタイトル情報が取れない場合はtitleタグから取得を試みる (#65)

refs #62

app/MetadataResolver/OGPResolver.php

@@ -24,6 +24,12 @@ class OGPResolver implements Resolver
         $metadata = new Metadata();
 
         $metadata->title = $this->findContent($xpath, '//meta[@*="og:title"]', '//meta[@*="twitter:title"]');
+        if (empty($metadata->title)) {
+            $nodes = $xpath->query('//title');
+            if ($nodes->length !== 0) {
+                $metadata->title = $nodes->item(0)->textContent;
+            }
+        }
         $metadata->description = $this->findContent($xpath, '//meta[@*="og:description"]', '//meta[@*="twitter:description"]');
         $metadata->image = $this->findContent($xpath, '//meta[@*="og:image"]', '//meta[@*="twitter:image"]');