fix: wait for approximate minimum bytes before probing for dimensions

Author: scissorsneedfoodtoo

utils/get-image-dimensions.js

@@ -4,26 +4,47 @@ const errorLogger = require('./error-logger');
 const { getCache, setCache } = require('./cache');
 const defaultDimensions = { width: 600, height: 400 };
 
+// Minimum required bytes for common image formats (approximate)
+const imageMinBytes = {
+  jpg: 410,
+  png: 33,
+  gif: 14,
+  webp: 30,
+  bmp: 26,
+  default: 256 // Fallback for other image types
+};
+
 const probeImage = async url => {
   const response = await fetch(url);
   if (!response.ok)
     throw new Error(`Failed to fetch image: ${response.statusText}`);
 
   const chunks = [];
+  let totalLength = 0;
   const reader = response.body;
 
   for await (const chunk of reader) {
     chunks.push(chunk);
+    totalLength += chunk.length;
 
     try {
-      // Try to determine image size with available data
-      const dimensions = imageSize(Buffer.concat(chunks));
+      const buffer = Buffer.concat(chunks, totalLength);
+
+      // Try to detect image format (first few bytes)
+      const { type } = imageSize(buffer);
+      const minBytes = imageMinBytes[type] || imageMinBytes.default;
+
+      // Check buffer length before probing image
+      if (buffer.length < minBytes) continue;
+
+      // Get dimensions
+      const dimensions = imageSize(buffer);
       if (dimensions.width && dimensions.height) {
-        response.body.destroy(); // Stop data stream
+        response.body.destroy(); // Stop downloading
         return dimensions;
       }
     } catch (err) {
-      // Keep reading if more data is needed
+      // Continue reading if more data is needed
     }
   }