add ingredient suggestions during recipe creation

backend/routes/recipes.js

@@ -21,6 +21,50 @@ function authenticateToken(req, res, next) {
   });
 }
 
+// Get ingredient suggestions for autocomplete
+router.get('/ingredients/suggestions', async (req, res) => {
+  try {
+    const { q } = req.query; // Search query
+    
+    if (!q || q.length < 2) {
+      return res.json([]);
+    }
+    
+    // Aggregate unique ingredient names from all recipes
+    const suggestions = await Recipe.aggregate([
+      { $unwind: '$ingredients' },
+      { 
+        $match: { 
+          'ingredients.name': { 
+            $regex: q, 
+            $options: 'i' 
+          } 
+        } 
+      },
+      { 
+        $group: { 
+          _id: { $toLower: '$ingredients.name' },
+          name: { $first: '$ingredients.name' },
+          count: { $sum: 1 }
+        } 
+      },
+      { $sort: { count: -1, name: 1 } },
+      { $limit: 10 },
+      { 
+        $project: { 
+          _id: 0, 
+          name: 1, 
+          count: 1 
+        } 
+      }
+    ]);
+    
+    res.json(suggestions);
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
 // Get all recipes
 router.get('/', async (req, res) => {
   try {