refactor: extract useInventoryFilter hook from inventory/page.tsx

frontend/hooks/useInventoryFilter.ts

@@ -0,0 +1,46 @@
+import { useState, useMemo } from 'react';
+import { Item } from '@/lib/db';
+
+export function useInventoryFilter(inventory: Item[]) {
+  const [searchQuery, setSearchQuery] = useState('');
+  const [expandedCategory, setExpandedCategory] = useState<string | null>(null);
+  const [boxSearchQuery, setBoxSearchQuery] = useState('');
+
+  // Get unique categories from inventory
+  const categories = useMemo(
+    () => Array.from(new Set(inventory.map(i => i.category))),
+    [inventory]
+  );
+
+  // Filter categories based on search query
+  const filteredCategories = useMemo(
+    () => categories.filter(c =>
+      c.toLowerCase().includes(searchQuery.toLowerCase()) ||
+      inventory.some(i => i.category === c && i.name.toLowerCase().includes(searchQuery.toLowerCase()))
+    ),
+    [categories, inventory, searchQuery]
+  );
+
+  // Get filtered items within a specific category
+  const getFilteredItems = (category: string) =>
+    inventory
+      .filter(i => i.category === category)
+      .filter(i => i.name.toLowerCase().includes(searchQuery.toLowerCase()));
+
+  // Get filtered boxes based on search
+  const getFilteredBoxes = (boxes: string[]) =>
+    boxes.filter(b => b.toLowerCase().includes(boxSearchQuery.toLowerCase()));
+
+  return {
+    searchQuery,
+    setSearchQuery,
+    expandedCategory,
+    setExpandedCategory,
+    boxSearchQuery,
+    setBoxSearchQuery,
+    categories,
+    filteredCategories,
+    getFilteredItems,
+    getFilteredBoxes
+  };
+}