// 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/material.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter_test/flutter_test.dart';

import 'semantics_tester.dart';

void main() {
  testWidgets('Sliver appBars - floating and pinned - correct elevation', (WidgetTester tester) async {
    await tester.pumpWidget(Localizations(
        locale: const Locale('en', 'us'),
        delegates: const <LocalizationsDelegate<dynamic>>[
          DefaultWidgetsLocalizations.delegate,
          DefaultMaterialLocalizations.delegate,
        ],
        child: Directionality(
          textDirection: TextDirection.ltr,
          child: MediaQuery(
            data: const MediaQueryData(),
            child: CustomScrollView(
              slivers: <Widget>[
                const SliverAppBar(
                  bottom: PreferredSize(
                    preferredSize: Size.fromHeight(28),
                    child: Text('Bottom'),
                  ),
                  backgroundColor: Colors.green,
                  floating: true,
                  primary: false,
                  automaticallyImplyLeading: false,
                ),
                SliverToBoxAdapter(child: Container(color: Colors.yellow, height: 50.0)),
                SliverToBoxAdapter(child: Container(color: Colors.red, height: 50.0)),
              ],
            ),
          ),
        ),
      ),
    );

    final RenderPhysicalModel renderObject = tester.renderObject<RenderPhysicalModel>(find.byType(PhysicalModel));
    expect(renderObject, isNotNull);
    expect(renderObject.elevation, 0.0);
  });

  testWidgets('Sliver appbars - floating and pinned - correct semantics', (WidgetTester tester) async {
    await tester.pumpWidget(
      Localizations(
        locale: const Locale('en', 'us'),
        delegates: const <LocalizationsDelegate<dynamic>>[
          DefaultWidgetsLocalizations.delegate,
          DefaultMaterialLocalizations.delegate,
        ],
        child: Directionality(
          textDirection: TextDirection.ltr,
          child: MediaQuery(
            data: const MediaQueryData(),
            child: CustomScrollView(
              slivers: <Widget>[
                const SliverAppBar(
                  title: Text('Hello'),
                  pinned: true,
                  floating: true,
                  expandedHeight: 200.0,
                ),
                SliverFixedExtentList(
                  itemExtent: 100.0,
                  delegate: SliverChildBuilderDelegate(
                    (BuildContext _, int index) {
                      return Container(
                        height: 100.0,
                        color: index.isEven ? Colors.red : Colors.yellow,
                        child: Text('Tile $index'),
                      );
                    },
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );

    final SemanticsTester semantics = SemanticsTester(tester);

    TestSemantics expectedSemantics = TestSemantics.root(
      children: <TestSemantics>[
        TestSemantics.rootChild(
          textDirection: TextDirection.ltr,
          children: <TestSemantics>[
            TestSemantics(
              children: <TestSemantics>[
                TestSemantics(
                  thickness: 0,
                  children: <TestSemantics>[
                    TestSemantics(
                      label: 'Hello',
                      elevation: 0,
                      flags: <SemanticsFlag>[SemanticsFlag.isHeader, SemanticsFlag.namesRoute],
                      textDirection: TextDirection.ltr,
                    ),
                  ],
                ),
                TestSemantics(
                  actions: <SemanticsAction>[SemanticsAction.scrollUp],
                  flags: <SemanticsFlag>[SemanticsFlag.hasImplicitScrolling],
                  scrollIndex: 0,
                  children: <TestSemantics>[
                    TestSemantics(
                      label: 'Tile 0',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 1',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 2',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 3',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 4',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                    TestSemantics(
                      label: 'Tile 5',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                    TestSemantics(
                      label: 'Tile 6',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                  ],
                ),
              ],
            ),
          ],
        ),
      ],
    );
    expect(semantics, hasSemantics(expectedSemantics, ignoreTransform: true, ignoreId: true, ignoreRect: true));

    await tester.fling(find.text('Tile 2'), const Offset(0, -600), 2000);
    await tester.pumpAndSettle();

    expectedSemantics = TestSemantics.root(
      children: <TestSemantics>[
        TestSemantics.rootChild(
          textDirection: TextDirection.ltr,
          children: <TestSemantics>[
            TestSemantics(
              children: <TestSemantics>[
                TestSemantics(
                  children: <TestSemantics>[
                    TestSemantics(
                      label: 'Hello',
                      flags: <SemanticsFlag>[SemanticsFlag.isHeader, SemanticsFlag.namesRoute],
                      textDirection: TextDirection.ltr,
                    ),
                  ],
                ),
                TestSemantics(
                  actions: <SemanticsAction>[SemanticsAction.scrollUp, SemanticsAction.scrollDown],
                  flags: <SemanticsFlag>[SemanticsFlag.hasImplicitScrolling],
                  scrollIndex: 10,
                  children: <TestSemantics>[
                    TestSemantics(
                      label: 'Tile 7',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                    TestSemantics(
                      label: 'Tile 8',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                    TestSemantics(
                      label: 'Tile 9',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                    TestSemantics(
                      label: 'Tile 10',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 11',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 12',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 13',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 14',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 15',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 16',
                      textDirection: TextDirection.ltr,
                    ),
                    TestSemantics(
                      label: 'Tile 17',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                    TestSemantics(
                      label: 'Tile 18',
                      textDirection: TextDirection.ltr,
                      flags: <SemanticsFlag>[SemanticsFlag.isHidden],
                    ),
                  ],
                ),
              ],
            ),
          ],
        ),
      ],
    );
    expect(semantics, hasSemantics(expectedSemantics, ignoreTransform: true, ignoreId: true, ignoreRect: true));
  });

  testWidgets('Sliver appbars - floating and pinned - second app bar stacks below', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    await tester.pumpWidget(
      Localizations(
        locale: const Locale('en', 'us'),
        delegates: const <LocalizationsDelegate<dynamic>>[
          DefaultWidgetsLocalizations.delegate,
          DefaultMaterialLocalizations.delegate,
        ],
        child: Directionality(
          textDirection: TextDirection.ltr,
          child: MediaQuery(
            data: const MediaQueryData(),
            child: CustomScrollView(
              controller: controller,
              slivers: <Widget>[
                const SliverAppBar(floating: true, pinned: true, expandedHeight: 200.0, title: Text('A')),
                const SliverAppBar(primary: false, pinned: true, title: Text('B')),
                SliverList(
                  delegate: SliverChildListDelegate(
                    const <Widget>[
                      Text('C'),
                      Text('D'),
                      SizedBox(height: 500.0),
                      Text('E'),
                      SizedBox(height: 500.0),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
    const Offset textPositionInAppBar = Offset(16.0, 18.0);
    expect(tester.getTopLeft(find.text('A')), textPositionInAppBar);
    // top app bar is 200.0 high at this point
    expect(tester.getTopLeft(find.text('B')), const Offset(0.0, 200.0) + textPositionInAppBar);
    // second app bar is 56.0 high
    expect(tester.getTopLeft(find.text('C')), const Offset(0.0, 200.0 + 56.0)); // height of both appbars
    final Size cSize = tester.getSize(find.text('C'));
    controller.jumpTo(200.0 - 56.0);
    await tester.pump();
    expect(tester.getTopLeft(find.text('A')), textPositionInAppBar);
    // top app bar is now only 56.0 high, same as second
    expect(tester.getTopLeft(find.text('B')), const Offset(0.0, 56.0) + textPositionInAppBar);
    expect(tester.getTopLeft(find.text('C')), const Offset(0.0, 56.0 * 2.0)); // height of both collapsed appbars
    expect(find.text('E'), findsNothing);
    controller.jumpTo(600.0);
    await tester.pump();
    expect(tester.getTopLeft(find.text('A')), textPositionInAppBar); // app bar is pinned at top
    expect(tester.getTopLeft(find.text('B')), const Offset(0.0, 56.0) + textPositionInAppBar); // second one too
    expect(find.text('C'), findsNothing); // contents are scrolled off though
    expect(find.text('D'), findsNothing);
    // we have scrolled 600.0 pixels
    // initial position of E was 200 + 56 + cSize.height + cSize.height + 500
    // we've scrolled that up by 600.0, meaning it's at that minus 600 now:
    expect(tester.getTopLeft(find.text('E')), Offset(0.0, 200.0 + 56.0 + cSize.height * 2.0 + 500.0 - 600.0));
  });

  testWidgets('Does not crash when there is less than minExtent remainingPaintExtent', (WidgetTester tester) async {
    // Regression test for https://github.com/flutter/flutter/issues/21887.
    final ScrollController controller = ScrollController();
    const double availableHeight = 50.0;
    await tester.pumpWidget(
      MaterialApp(
        home: Center(
          child: Container(
            height: availableHeight,
            color: Colors.green,
            child: CustomScrollView(
              controller: controller,
              slivers: <Widget>[
                const SliverAppBar(
                  pinned: true,
                  floating: true,
                  expandedHeight: 120.0,
                ),
                SliverList(
                  delegate: SliverChildListDelegate(List<Widget>.generate(20, (int i) {
                    return SizedBox(
                      height: 100.0,
                      child: Text('Tile $i'),
                    );
                  })),
                ),
              ],
            ),
          ),
        ),
      ),
    );
    final RenderSliverFloatingPinnedPersistentHeader render = tester.renderObject(find.byType(SliverAppBar));
    expect(render.minExtent, greaterThan(availableHeight)); // Precondition
    expect(render.geometry!.scrollExtent, 120.0);
    expect(render.geometry!.paintExtent, availableHeight);
    expect(render.geometry!.layoutExtent, availableHeight);

    controller.jumpTo(200.0);
    await tester.pumpAndSettle();
    expect(render.geometry!.scrollExtent, 120.0);
    expect(render.geometry!.paintExtent, availableHeight);
    expect(render.geometry!.layoutExtent, 0.0);
  });

  testWidgets('Pinned and floating SliverAppBar sticks to top the content is scroll down', (WidgetTester tester) async {
    const Key anchor = Key('drag');
    await tester.pumpWidget(
      MaterialApp(
        home: Center(
          child: Container(
            height: 300,
            color: Colors.green,
            child: CustomScrollView(
              physics: const BouncingScrollPhysics(),
              slivers: <Widget>[
                const SliverAppBar(
                  pinned: true,
                  floating: true,
                  expandedHeight: 100.0,
                ),
                SliverToBoxAdapter(child: Container(key: anchor, color: Colors.red, height: 100)),
                SliverToBoxAdapter(child: Container(height: 600, color: Colors.green)),
              ],
            ),
          ),
        ),
      ),
    );
    final RenderSliverFloatingPinnedPersistentHeader render = tester.renderObject(find.byType(SliverAppBar));

    const double scrollDistance = 40;
    final TestGesture gesture = await tester.press(find.byKey(anchor));
    await gesture.moveBy(const Offset(0, scrollDistance));
    await tester.pump();

    expect(render.geometry!.paintOrigin, -scrollDistance);
  });

  testWidgets('Floating SliverAppBar sticks to top the content is scroll down', (WidgetTester tester) async {
    const Key anchor = Key('drag');
    await tester.pumpWidget(
      MaterialApp(
        home: Center(
          child: Container(
            height: 300,
            color: Colors.green,
            child: CustomScrollView(
              physics: const BouncingScrollPhysics(),
              slivers: <Widget>[
                const SliverAppBar(
                  pinned: false,
                  floating: true,
                  expandedHeight: 100.0,
                ),
                SliverToBoxAdapter(child: Container(key: anchor, color: Colors.red, height: 100)),
                SliverToBoxAdapter(child: Container(height: 600, color: Colors.green)),
              ],
            ),
          ),
        ),
      ),
    );
    final RenderSliverFloatingPersistentHeader render = tester.renderObject(find.byType(SliverAppBar));

    const double scrollDistance = 40;
    final TestGesture gesture = await tester.press(find.byKey(anchor));
    await gesture.moveBy(const Offset(0, scrollDistance));
    await tester.pump();

    expect(render.geometry!.paintOrigin, -scrollDistance);
  });

  testWidgets('Pinned SliverAppBar sticks to top the content is scroll down', (WidgetTester tester) async {
    const Key anchor = Key('drag');
    await tester.pumpWidget(
      MaterialApp(
        home: Center(
          child: Container(
            height: 300,
            color: Colors.green,
            child: CustomScrollView(
              physics: const BouncingScrollPhysics(),
              slivers: <Widget>[
                const SliverAppBar(
                  pinned: true,
                  floating: false,
                  expandedHeight: 100.0,
                ),
                SliverToBoxAdapter(child: Container(key: anchor, color: Colors.red, height: 100)),
                SliverToBoxAdapter(child: Container(height: 600, color: Colors.green)),
              ],
            ),
          ),
        ),
      ),
    );
    final RenderSliverPinnedPersistentHeader render = tester.renderObject(find.byType(SliverAppBar));

    const double scrollDistance = 40;
    final TestGesture gesture = await tester.press(find.byKey(anchor));
    await gesture.moveBy(const Offset(0, scrollDistance));
    await tester.pump();

    expect(render.geometry!.paintOrigin, -scrollDistance);
  });
}