// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:flutter/cupertino.dart';
import 'package:flutter_api_samples/cupertino/nav_bar/cupertino_sliver_nav_bar.0.dart'
    as example;
import 'package:flutter_test/flutter_test.dart';

const Offset dragUp = Offset(0.0, -150.0);

void setWindowToPortrait(
  WidgetTester tester, {
  Size size = const Size(2400.0, 3000.0),
}) {
  tester.view.physicalSize = size;
  addTearDown(tester.view.reset);
}

void main() {
  testWidgets(
    'Collapse and expand CupertinoSliverNavigationBar changes title position',
    (WidgetTester tester) async {
      setWindowToPortrait(tester);
      await tester.pumpWidget(const example.SliverNavBarApp());

      // Large title is visible and at lower position.
      expect(tester.getBottomLeft(find.text('Contacts').first).dy, 88.0);
      await tester.fling(find.text('Drag me up'), dragUp, 500.0);
      await tester.pumpAndSettle();

      // Large title is hidden and at higher position.
      expect(
        tester.getBottomLeft(find.text('Contacts').first).dy,
        36.0 + 8.0,
      ); // Static part + _kNavBarBottomPadding.
    },
  );

  testWidgets(
    'Middle widget is visible in both collapsed and expanded states',
    (WidgetTester tester) async {
      setWindowToPortrait(tester);
      await tester.pumpWidget(const example.SliverNavBarApp());

      // Navigate to a page that has both middle and large titles.
      final Finder nextButton = find.text('Go to Next Page');
      expect(nextButton, findsOneWidget);
      await tester.tap(nextButton);
      await tester.pumpAndSettle();

      // Both middle and large titles are visible.
      expect(tester.getBottomLeft(find.text('Contacts Group').first).dy, 30.5);
      expect(tester.getBottomLeft(find.text('Family').first).dy, 88.0);

      await tester.fling(find.text('Drag me up'), dragUp, 500.0);
      await tester.pumpAndSettle();

      // Large title is hidden and middle title is visible.
      expect(tester.getBottomLeft(find.text('Contacts Group').first).dy, 30.5);
      expect(
        tester.getBottomLeft(find.text('Family').first).dy,
        36.0 + 8.0,
      ); // Static part + _kNavBarBottomPadding.
    },
  );

  testWidgets(
    'CupertinoSliverNavigationBar with previous route has back button',
    (WidgetTester tester) async {
      setWindowToPortrait(tester);
      await tester.pumpWidget(const example.SliverNavBarApp());

      // Navigate to a page that has back button
      final Finder nextButton = find.text('Go to Next Page');
      expect(nextButton, findsOneWidget);
      await tester.tap(nextButton);
      await tester.pumpAndSettle();
      expect(nextButton, findsNothing);

      // Go back to the previous page.
      final Finder backButton = find.byType(CupertinoButton);
      expect(backButton, findsOneWidget);
      await tester.tap(backButton);
      await tester.pumpAndSettle();
      expect(nextButton, findsOneWidget);
    },
  );
}