try to extract title, pubDate, updatedDate automagically

src/index.ts

@@ -52,12 +52,23 @@ export default function gemtext(config: GemtextConfig = {}): AstroIntegration {
 
                         const body = lines.slice(bodyStartLineIndex).join("\n")
 
+                      const filepath = fileURLToPath(fileUrl);
+                      const filename = filepath.slice(filepath.lastIndexOf("/") + 1);
                       const slug =
                         typeof data["slug"] === "string" ?
                           data["slug"]
-                            :   fileURLToPath(fileUrl).slice(
+                          : filename;
-                                    fileURLToPath(fileUrl).lastIndexOf("/") + 1,
+
-                                )
+                        data['title'] = data['title']
+                          ?? lines.slice(bodyStartLineIndex).find(line => line.startsWith('# '))?.slice(2);
+                        data['pubDate'] = data['pubDate']
+                          ?? validDateOrUndefined(lines.slice(bodyStartLineIndex).find(line => line.startsWith('Published on: '))?.slice(14))
+                          ?? validDateOrUndefined(filename.replace(/\.[^.]\+$/, ''))
+                          ?? validDateOrUndefined(slug.replace(/\.[^.]\+$/, ''));
+                        data['updatedDate'] = data['updatedDate']
+                          ?? validDateOrUndefined(lines.slice(bodyStartLineIndex).find(line => line.startsWith('Updated on: '))?.slice(14))
+                          ?? validDateOrUndefined(filename.replace(/\.[^.]\+$/, ''))
+                          ?? validDateOrUndefined(slug.replace(/\.[^.]\+$/, ''));
 
                         return {
                             data,
@@ -71,3 +82,11 @@ export default function gemtext(config: GemtextConfig = {}): AstroIntegration {
         },
     }
 }
+
+const validDateOrUndefined = (x: unknown) => {
+  const d = new Date(x as string);
+  if (isNaN(d.valueOf())) {
+    return undefined;
+  }
+  return d;
+};