move non pages out of pages dir

website/src/metadata_parser.js

@@ -0,0 +1,34 @@
+const ALLOW_MANY = ['by', 'url', 'genre', 'license'];
+
+export function getMetadata(raw_code) {
+  const comment_regexp = /\/\*([\s\S]*?)\*\/|\/\/(.*)$/gm;
+  const comments = [...raw_code.matchAll(comment_regexp)].map((c) => (c[1] || c[2] || '').trim());
+  const tags = {};
+
+  const [prefix, title] = (comments[0] || '').split('"');
+  if (prefix.trim() === '' && title !== undefined) {
+    tags['title'] = title;
+  }
+
+  for (const comment of comments) {
+    const tag_matches = comment.split('@').slice(1);
+    for (const tag_match of tag_matches) {
+      let [tag, tag_value] = tag_match.split(/ (.*)/s);
+      tag = tag.trim();
+      tag_value = (tag_value || '').replaceAll(/ +/g, ' ').trim();
+
+      if (ALLOW_MANY.includes(tag)) {
+        const tag_list = tag_value
+          .split(/[,\n]/)
+          .map((t) => t.trim())
+          .filter((t) => t !== '');
+        tags[tag] = tag in tags ? tags[tag].concat(tag_list) : tag_list;
+      } else {
+        tag_value = tag_value.replaceAll(/\s+/g, ' ');
+        tags[tag] = tag in tags ? tags[tag] + ' ' + tag_value : tag_value;
+      }
+    }
+  }
+
+  return tags;
+}