Adding images to scraping data (#157)

* Fredy now supports pulling the main Image from the listing and send it together with the usual information

lib/utils.js

@@ -68,9 +68,29 @@ export async function refreshConfig() {
     console.error('Error reading config file', error);
   }
 }
+
+const RE_GT = />/g;
+const RE_WEBP = /\/format\/webp/gi;
+const RE_EXT = /\.(jpe?g|png|gif)(\?.*)?$/i;
+const HTTPS_PREFIX = 'https://';
+
+const normalizeImageUrl = (url) => {
+  if (typeof url !== 'string' || url.length === 0) return null;
+
+  let u = url.trim().replace(RE_GT, '');
+  if (RE_WEBP.test(u)) u = u.replace(RE_WEBP, '/format/jpg');
+  if (!u.startsWith(HTTPS_PREFIX)) return null;
+  if (!RE_EXT.test(u)) {
+    const jpgIdx = u.toLowerCase().lastIndexOf('.jpg');
+    if (jpgIdx > -1) u = u.slice(0, jpgIdx + 4);
+  }
+  return u;
+};
+
 await refreshConfig();
 
 export { isOneOf };
+export { normalizeImageUrl };
 export { inDevMode };
 export { nullOrEmpty };
 export { duringWorkingHoursOrNotSet };