// Author: fruit.com.cn
// 职责：验证首页跨页动画的目标保留、连点打断和减少动画行为。
import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:fruitshorts/pages/recommend/home_tab_motion_controller.dart';

const _midpoint = Duration(milliseconds: 90);
const _finish = Duration(milliseconds: 300);

Widget _pager(HomeTabMotionController controller, List<int> accepted) =>
    MaterialApp(
      home: PageView(
        controller: controller,
        onPageChanged: (index) {
          if (controller.acceptsSelection(index)) accepted.add(index);
        },
        children: const [
          ColoredBox(color: Colors.black),
          ColoredBox(color: Colors.red),
          ColoredBox(color: Colors.grey),
        ],
      ),
    );

void main() {
  testWidgets(
    'should_ignore_intermediate_page_when_clicking_across_two_pages',
    (tester) async {
      int? settled;
      final controller = HomeTabMotionController(
        onSettled: (index) => settled = index,
      );
      addTearDown(controller.dispose);
      final accepted = <int>[];
      await tester.pumpWidget(_pager(controller, accepted));
      final transition = controller.selectPage(2, reduceMotion: false);
      await tester.pump();
      await tester.pump(_midpoint);
      expect(controller.pagePosition, inExclusiveRange(0.0, 2.0));
      expect(controller.acceptsSelection(1), isFalse);
      expect(accepted, isNot(contains(1)));
      await tester.pump(_finish);
      await transition;
      expect(controller.pagePosition, 2);
      expect(settled, 2);
      expect(controller.acceptsSelection(1), isTrue);
    },
  );

  testWidgets('should_keep_last_target_when_clicks_interrupt_each_other', (
    tester,
  ) async {
    int? settled;
    final controller = HomeTabMotionController(
      onSettled: (index) => settled = index,
    );
    addTearDown(controller.dispose);
    await tester.pumpWidget(_pager(controller, []));
    final first = controller.selectPage(2, reduceMotion: false);
    await tester.pump();
    await tester.pump(_midpoint);
    final last = controller.selectPage(0, reduceMotion: false);
    await tester.pump();
    expect(controller.acceptsSelection(2), isFalse);
    await tester.pump(_finish);
    await Future.wait([first, last]);
    expect(controller.pagePosition, 0);
    expect(settled, 0);
  });

  testWidgets('should_jump_to_target_when_reduced_motion_is_enabled', (
    tester,
  ) async {
    int? settled;
    final controller = HomeTabMotionController(
      onSettled: (index) => settled = index,
    );
    addTearDown(controller.dispose);
    await tester.pumpWidget(_pager(controller, []));
    await controller.selectPage(2, reduceMotion: true);
    expect(controller.pagePosition, 2);
    expect(settled, 2);
  });

  testWidgets('should_release_target_when_user_drag_interrupts_animation', (
    tester,
  ) async {
    final controller = HomeTabMotionController(onSettled: (_) {});
    addTearDown(controller.dispose);
    await tester.pumpWidget(_pager(controller, []));
    final transition = controller.selectPage(2, reduceMotion: false);
    await tester.pump();
    await tester.pump(_midpoint);
    final gesture = await tester.startGesture(
      tester.getCenter(find.byType(PageView)),
    );
    await gesture.moveBy(const Offset(60, 0));
    await tester.pump();
    await transition;
    expect(controller.acceptsSelection(0), isTrue);
    expect(controller.acceptsSelection(1), isTrue);
    await gesture.up();
    await tester.pumpAndSettle();
  });
}