feat: add useSettings hook for admin price management

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/admin/settings/__tests__/useSettings.test.js

@@ -0,0 +1,71 @@
+import { renderHook, act } from '@testing-library/react';
+import { vi, describe, it, expect, beforeEach } from 'vitest';
+
+const { mockIn, mockEq } = vi.hoisted(() => ({
+  mockIn: vi.fn(),
+  mockEq: vi.fn(),
+}));
+
+vi.mock('../../../lib/supabase', () => ({
+  supabase: {
+    from: vi.fn(() => ({
+      select: vi.fn(() => ({ in: mockIn })),
+      update: vi.fn(() => ({ eq: mockEq })),
+    })),
+  },
+}));
+
+import { useSettings } from '../useSettings';
+
+describe('useSettings', () => {
+  beforeEach(() => vi.clearAllMocks());
+
+  it('loads prices on mount', async () => {
+    mockIn.mockResolvedValue({
+      data: [{ key: 'price_200', value: '2000' }, { key: 'price_300', value: '3000' }],
+      error: null,
+    });
+    const { result } = renderHook(() => useSettings());
+    await act(async () => {});
+    expect(result.current.loading).toBe(false);
+    expect(result.current.prices).toEqual({ 200: 2000, 300: 3000 });
+  });
+
+  it('sets error when fetch fails', async () => {
+    mockIn.mockResolvedValue({ data: null, error: { message: 'DB error' } });
+    const { result } = renderHook(() => useSettings());
+    await act(async () => {});
+    expect(result.current.error).toBe('DB error');
+  });
+
+  it('updatePrice calls update().eq() and updates local state', async () => {
+    mockIn.mockResolvedValue({
+      data: [{ key: 'price_200', value: '2000' }, { key: 'price_300', value: '3000' }],
+      error: null,
+    });
+    mockEq.mockResolvedValue({ error: null });
+    const { result } = renderHook(() => useSettings());
+    await act(async () => {});
+    await act(async () => {
+      await result.current.updatePrice('price_200', 1800);
+    });
+    expect(mockEq).toHaveBeenCalledWith('key', 'price_200');
+    expect(result.current.prices[200]).toBe(1800);
+  });
+
+  it('updatePrice returns error without mutating state when DB fails', async () => {
+    mockIn.mockResolvedValue({
+      data: [{ key: 'price_200', value: '2000' }, { key: 'price_300', value: '3000' }],
+      error: null,
+    });
+    mockEq.mockResolvedValue({ error: { message: 'update failed' } });
+    const { result } = renderHook(() => useSettings());
+    await act(async () => {});
+    let updateResult;
+    await act(async () => {
+      updateResult = await result.current.updatePrice('price_200', 9999);
+    });
+    expect(updateResult.error.message).toBe('update failed');
+    expect(result.current.prices[200]).toBe(2000);
+  });
+});

src/admin/settings/useSettings.js

@@ -0,0 +1,46 @@
+import { useState, useEffect, useCallback } from 'react';
+import { supabase } from '../../lib/supabase';
+
+export function useSettings() {
+  const [prices, setPrices] = useState({ 200: 2000, 300: 3000 });
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+
+  const fetchPrices = useCallback(async () => {
+    const { data, error } = await supabase
+      .from('settings')
+      .select('key, value')
+      .in('key', ['price_200', 'price_300']);
+
+    if (error) {
+      setError(error.message);
+    } else if (data) {
+      const map = {};
+      data.forEach(({ key, value }) => {
+        const thickness = parseInt(key.replace('price_', ''), 10);
+        map[thickness] = Number(value);
+      });
+      setPrices((prev) => ({ ...prev, ...map }));
+    }
+    setLoading(false);
+  }, []);
+
+  useEffect(() => {
+    fetchPrices();
+  }, [fetchPrices]);
+
+  const updatePrice = async (key, value) => {
+    const { error } = await supabase
+      .from('settings')
+      .update({ value: String(value), updated_at: new Date().toISOString() })
+      .eq('key', key);
+
+    if (!error) {
+      const thickness = parseInt(key.replace('price_', ''), 10);
+      setPrices((prev) => ({ ...prev, [thickness]: Number(value) }));
+    }
+    return { error };
+  };
+
+  return { prices, loading, error, updatePrice };
+}