feat: Add backfill script for image brightness stats and display them in the UI.

server.js

@@ -116,14 +116,43 @@ app.post('/upload', authenticate, upload.single('image'), async (req, res) => {
 
     // Generate thumbnail
     try {
+        const image = sharp(req.file.path);
+        const metadata = await image.metadata(); // Get metadata first
+        const stats = await image.stats(); // Get stats (includes mean for channels)
+
+        // Calculate Average Brightness
+        // Simple average of R, G, B mean values (0-255)
+        const brightness = Math.round((stats.channels[0].mean + stats.channels[1].mean + stats.channels[2].mean) / 3);
+
         const thumbnailFilename = req.file.filename.replace(path.extname(req.file.filename), '_thumb.avif');
         const thumbnailPath = path.join(path.dirname(req.file.path), thumbnailFilename);
+        const dirPath = path.dirname(req.file.path);
 
-        await sharp(req.file.path)
+        await image
             .resize(320) // Resize to 320px width, auto height
             .toFormat('avif')
             .toFile(thumbnailPath);
 
+        // Update daily stats.json
+        const statsFile = path.join(dirPath, 'stats.json');
+        let dailyStats = [];
+        try {
+            if (fs.existsSync(statsFile)) {
+                dailyStats = JSON.parse(fs.readFileSync(statsFile, 'utf8'));
+            }
+        } catch (e) { console.error('Error reading stats.json', e); }
+
+        dailyStats.push({
+            timestamp: new Date().toISOString(),
+            filename: req.file.filename,
+            brightness
+        });
+
+        // Write back stats
+        try {
+            fs.writeFileSync(statsFile, JSON.stringify(dailyStats, null, 2));
+        } catch (e) { console.error('Error writing stats.json', e); }
+
         res.json({
             success: true,
             cameraId,
@@ -132,17 +161,18 @@ app.post('/upload', authenticate, upload.single('image'), async (req, res) => {
             thumbnail: thumbnailFilename,
             thumbnailPath: thumbnailPath,
             size: req.file.size,
+            brightness,
             timestamp: new Date().toISOString()
         });
     } catch (error) {
-        console.error('Thumbnail generation failed:', error);
-        // Still return success for the upload even if thumbnail fails
+        console.error('Processing failed:', error);
+        // Still return success for the upload even if processing fails
         res.json({
             success: true,
             cameraId,
             filename: req.file.filename,
             path: req.file.path,
-            thumbnailError: error.message,
+            error: error.message,
             size: req.file.size,
             timestamp: new Date().toISOString()
         });
@@ -378,7 +408,16 @@ app.get('/cameras/:cameraId/:year/:month/:day', async (req, res) => {
         // Sort by filename (timestamp) descending
         images.sort((a, b) => b.filename.localeCompare(a.filename));
 
-        res.json({ images });
+        // Load stats if available
+        let stats = [];
+        try {
+            const statsFile = path.join(datePath, 'stats.json');
+            if (fs.existsSync(statsFile)) {
+                stats = JSON.parse(fs.readFileSync(statsFile, 'utf8'));
+            }
+        } catch (e) { console.error('Error reading stats.json', e); }
+
+        res.json({ images, stats });
     } catch (error) {
         res.status(500).json({ error: 'Failed to list images', details: error.message });
     }