import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:jiu_client/core/models/page_result.dart';
import 'package:jiu_client/models/product.dart';
import 'package:jiu_client/providers/product_provider.dart';
import 'package:jiu_client/screens/products/products_screen.dart';

// ---------------------------------------------------------------------------
// Fake notifier helpers
// ---------------------------------------------------------------------------

/// A notifier that immediately emits a fixed state.
class _FakeProductNotifier extends ProductListNotifier {
  final AsyncValue<PageResult<Product>> _fixed;
  _FakeProductNotifier(this._fixed);

  @override
  Future<PageResult<Product>> build() async {
    state = _fixed;
    return state.value ?? const PageResult(data: [], total: 0, page: 1, pageSize: 20);
  }

  @override
  void reload() {}

  @override
  void setKeyword(String keyword) {}

  @override
  void setPage(int page) {}

  @override
  Future<void> createProduct(Map<String, dynamic> data) async {}

  @override
  Future<void> updateProduct(int id, Map<String, dynamic> data) async {}

  @override
  Future<void> deleteProduct(int id) async {}
}

/// A notifier that stays permanently in loading state (build never completes).
class _FakeLoadingProductNotifier extends ProductListNotifier {
  @override
  Future<PageResult<Product>> build() {
    // Never completes — keeps the widget in CircularProgressIndicator state.
    return Completer<PageResult<Product>>().future;
  }

  @override
  void reload() {}

  @override
  void setKeyword(String keyword) {}

  @override
  void setPage(int page) {}

  @override
  Future<void> createProduct(Map<String, dynamic> data) async {}

  @override
  Future<void> updateProduct(int id, Map<String, dynamic> data) async {}

  @override
  Future<void> deleteProduct(int id) async {}
}

/// Helper to build a testable app wrapping [ProductsScreen].
Widget _buildApp(AsyncValue<PageResult<Product>> state) {
  return ProviderScope(
    overrides: [
      productListProvider.overrideWith(() => _FakeProductNotifier(state)),
    ],
    child: const MaterialApp(home: Scaffold(body: ProductsScreen())),
  );
}

Widget _buildLoadingApp() {
  return ProviderScope(
    overrides: [
      productListProvider.overrideWith(() => _FakeLoadingProductNotifier()),
    ],
    child: const MaterialApp(home: Scaffold(body: ProductsScreen())),
  );
}

// ---------------------------------------------------------------------------
// Tests
// ---------------------------------------------------------------------------
// TODO: ProductsScreen 已重构为 options tab 页，productListProvider 已不挂载，测试待重写
void main() {
  testWidgets('shows CircularProgressIndicator while loading', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    await tester.pumpWidget(_buildLoadingApp());
    await tester.pump();

    expect(find.byType(CircularProgressIndicator), findsOneWidget);
  });

  testWidgets('shows error message on load failure', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    await tester.pumpWidget(
      _buildApp(AsyncValue.error('网络连接失败', StackTrace.empty)),
    );
    await tester.pump();

    expect(find.text('暂无数据，网络不可用'), findsOneWidget);
    expect(find.text('重试'), findsOneWidget);
  });

  testWidgets('shows 暂无商品 when list is empty', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const emptyResult = PageResult<Product>(
      data: [],
      total: 0,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(const AsyncValue.data(emptyResult)));
    await tester.pump();

    expect(find.text('暂无商品'), findsOneWidget);
  });

  testWidgets('shows product list with name code and unit', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const products = [
      Product(id: 1, code: 'P001', name: '五粮液', unit: '瓶'),
      Product(id: 2, code: 'P002', name: '茅台', unit: '瓶'),
    ];

    final result = PageResult<Product>(
      data: products,
      total: 2,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(AsyncValue.data(result)));
    await tester.pump();

    expect(find.text('五粮液'), findsOneWidget);
    expect(find.text('茅台'), findsOneWidget);
    expect(find.text('P001'), findsOneWidget);
    expect(find.text('P002'), findsOneWidget);
  });

  testWidgets('shows 新建 button in toolbar', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const emptyResult = PageResult<Product>(
      data: [],
      total: 0,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(const AsyncValue.data(emptyResult)));
    await tester.pump();

    expect(find.text('新建'), findsOneWidget);
  });

  testWidgets('tapping 新建 opens product form dialog', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const emptyResult = PageResult<Product>(
      data: [],
      total: 0,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(const AsyncValue.data(emptyResult)));
    await tester.pump();

    await tester.tap(find.text('新建'));
    await tester.pumpAndSettle();

    // Dialog should appear with "新建商品" title
    expect(find.text('新建商品'), findsOneWidget);
    // Form should have 商品名称 and 商品编码 fields
    expect(find.text('商品名称'), findsAtLeastNWidgets(1));
    expect(find.text('商品编码'), findsAtLeastNWidgets(1));
  });

  testWidgets('product form shows not-empty error', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const emptyResult = PageResult<Product>(
      data: [],
      total: 0,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(const AsyncValue.data(emptyResult)));
    await tester.pump();

    await tester.tap(find.text('新建'));
    await tester.pumpAndSettle();

    // Tap save without filling required fields
    await tester.tap(find.text('保存'));
    await tester.pump();

    expect(find.text('不能为空'), findsAtLeastNWidgets(1));
  });

  testWidgets('shows delete confirmation dialog', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const products = [
      Product(id: 1, code: 'P001', name: '五粮液', unit: '瓶'),
    ];

    final result = PageResult<Product>(
      data: products,
      total: 1,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(AsyncValue.data(result)));
    await tester.pump();

    await tester.tap(find.byKey(const Key('btn_delete_1')));
    await tester.pumpAndSettle();

    expect(find.text('确认删除'), findsOneWidget);
    expect(find.textContaining('五粮液'), findsAtLeastNWidgets(1));
    // Confirm dialog has 取消 and 删除 buttons — 删除 may appear in both the
    // list row action button and the dialog, so use findsAtLeastNWidgets(1).
    expect(find.text('取消'), findsOneWidget);
    expect(find.text('删除'), findsAtLeastNWidgets(1));
  });

  testWidgets('tapping edit opens edit dialog with prefilled values', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const products = [
      Product(id: 1, code: 'P001', name: '五粮液', unit: '瓶', brand: '五粮液集团'),
    ];

    final result = PageResult<Product>(
      data: products,
      total: 1,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(AsyncValue.data(result)));
    await tester.pump();

    await tester.tap(find.byKey(const Key('btn_edit_1')));
    await tester.pumpAndSettle();

    // Edit dialog title
    expect(find.text('编辑商品'), findsOneWidget);
    // Fields should be prefilled
    expect(find.widgetWithText(TextFormField, '五粮液'), findsOneWidget);
    expect(find.widgetWithText(TextFormField, 'P001'), findsOneWidget);
  });

  testWidgets('shows total count in pagination bar', skip: true, (tester) async {
    tester.view.physicalSize = const Size(1280, 800);
    tester.view.devicePixelRatio = 1.0;
    addTearDown(tester.view.resetPhysicalSize);

    const products = [
      Product(id: 1, code: 'P001', name: '五粮液', unit: '瓶'),
    ];

    final result = PageResult<Product>(
      data: products,
      total: 42,
      page: 1,
      pageSize: 20,
    );

    await tester.pumpWidget(_buildApp(AsyncValue.data(result)));
    await tester.pump();

    expect(find.textContaining('42'), findsAtLeastNWidgets(1));
  });
}