// Copyright 2013 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 'dart:math' as math;
import 'dart:typed_data';

import 'package:test/bootstrap/browser.dart';
import 'package:test/test.dart';
import 'package:ui/src/engine.dart';
import 'package:ui/ui.dart' as ui;
import 'package:ui/ui_web/src/ui_web.dart' as ui_web;

import 'package:web_engine_tester/golden_tester.dart';

import 'common.dart';

void main() {
  internalBootstrapBrowserTest(() => testMain);
}

const ui.Rect kDefaultRegion = ui.Rect.fromLTRB(0, 0, 500, 250);

void testMain() {
  group('CkCanvas', () {
    setUpCanvasKitTest();

    setUp(() {
      renderer.fontCollection.debugResetFallbackFonts();
      renderer.fontCollection.fontFallbackManager!.downloadQueue.fallbackFontUrlPrefixOverride = 'assets/fallback_fonts/';
    });

    test('renders using non-recording canvas if weak refs are supported',
        () async {
      final CkPictureRecorder recorder = CkPictureRecorder();
      final CkCanvas canvas = recorder.beginRecording(kDefaultRegion);
      expect(canvas.runtimeType, CkCanvas);
      drawTestPicture(canvas);
      await matchPictureGolden(
        'canvaskit_picture.png',
        recorder.endRecording(),
        region: kDefaultRegion,
      );
    });

    test(
        'text style - foreground/background/color do not leak across paragraphs',
        () async {
      const double testWidth = 440;
      const double middle = testWidth / 2;
      CkParagraph createTestParagraph(
          {ui.Color? color, CkPaint? foreground, CkPaint? background}) {
        final CkParagraphBuilder builder =
            CkParagraphBuilder(CkParagraphStyle());
        builder.pushStyle(CkTextStyle(
          fontSize: 16,
          color: color,
          foreground: foreground,
          background: background,
        ));
        final StringBuffer text = StringBuffer();
        if (color == null && foreground == null && background == null) {
          text.write('Default');
        } else {
          if (color != null) {
            text.write('Color');
          }
          if (foreground != null) {
            if (text.isNotEmpty) {
              text.write('+');
            }
            text.write('Foreground');
          }
          if (background != null) {
            if (text.isNotEmpty) {
              text.write('+');
            }
            text.write('Background');
          }
        }
        builder.addText(text.toString());
        final CkParagraph paragraph = builder.build();
        paragraph.layout(const ui.ParagraphConstraints(width: testWidth));
        return paragraph;
      }

      final List<ParagraphFactory> variations = <ParagraphFactory>[
        () => createTestParagraph(),
        () => createTestParagraph(color: const ui.Color(0xFF009900)),
        () => createTestParagraph(
            foreground: CkPaint()..color = const ui.Color(0xFF990000)),
        () => createTestParagraph(
            background: CkPaint()..color = const ui.Color(0xFF7777FF)),
        () => createTestParagraph(
              color: const ui.Color(0xFFFF00FF),
              background: CkPaint()..color = const ui.Color(0xFF0000FF),
            ),
        () => createTestParagraph(
              foreground: CkPaint()..color = const ui.Color(0xFF00FFFF),
              background: CkPaint()..color = const ui.Color(0xFF0000FF),
            ),
      ];

      final CkPictureRecorder recorder = CkPictureRecorder();
      final CkCanvas canvas = recorder.beginRecording(ui.Rect.largest);
      canvas.translate(10, 10);

      for (final ParagraphFactory from in variations) {
        for (final ParagraphFactory to in variations) {
          canvas.save();
          final CkParagraph fromParagraph = from();
          canvas.drawParagraph(fromParagraph, ui.Offset.zero);

          final ui.Offset leftEnd = ui.Offset(
              fromParagraph.maxIntrinsicWidth + 10, fromParagraph.height / 2);
          final ui.Offset rightEnd = ui.Offset(middle - 10, leftEnd.dy);
          const ui.Offset tipOffset = ui.Offset(-5, -5);
          canvas.drawLine(leftEnd, rightEnd, CkPaint());
          canvas.drawLine(rightEnd, rightEnd + tipOffset, CkPaint());
          canvas.drawLine(
              rightEnd, rightEnd + tipOffset.scale(1, -1), CkPaint());

          canvas.translate(middle, 0);
          canvas.drawParagraph(to(), ui.Offset.zero);
          canvas.restore();
          canvas.translate(0, 22);
        }
      }

      final CkPicture picture = recorder.endRecording();
      await matchPictureGolden(
        'canvaskit_text_styles_do_not_leak.png',
        picture,
        region: const ui.Rect.fromLTRB(0, 0, testWidth, 850),
      );
    });

    // Make sure we clear the canvas in between frames.
    test('empty frame after contentful frame', () async {
      // First draw a frame with a red rectangle
      final CkPictureRecorder recorder = CkPictureRecorder();
      final CkCanvas canvas = recorder.beginRecording(ui.Rect.largest);
      canvas.drawRect(const ui.Rect.fromLTRB(20, 20, 100, 100),
          CkPaint()..color = const ui.Color(0xffff0000));
      final CkPicture picture = recorder.endRecording();
      final LayerSceneBuilder builder = LayerSceneBuilder();
      builder.pushOffset(0, 0);
      builder.addPicture(ui.Offset.zero, picture);
      final LayerTree layerTree = builder.build().layerTree;
      CanvasKitRenderer.instance.rasterizer.draw(layerTree);

      // Now draw an empty layer tree and confirm that the red rectangle is
      // no longer drawn.
      final LayerSceneBuilder emptySceneBuilder = LayerSceneBuilder();
      emptySceneBuilder.pushOffset(0, 0);
      final LayerTree emptyLayerTree = emptySceneBuilder.build().layerTree;
      CanvasKitRenderer.instance.rasterizer.draw(emptyLayerTree);

      await matchGoldenFile('canvaskit_empty_scene.png',
          region: const ui.Rect.fromLTRB(0, 0, 100, 100));
    });

    // Regression test for https://github.com/flutter/flutter/issues/121758
    test('resources used in temporary surfaces for Image.toByteData can cross to rendering overlays', () async {
      final Rasterizer rasterizer = CanvasKitRenderer.instance.rasterizer;
      RenderCanvasFactory.instance.debugClear();

      ui_web.platformViewRegistry.registerViewFactory(
        'test-platform-view',
        (int viewId) => createDomHTMLDivElement()..id = 'view-0',
      );
      await createPlatformView(0, 'test-platform-view');

      CkPicture makeTextPicture(String text, ui.Offset offset) {
        final CkPictureRecorder recorder = CkPictureRecorder();
        final CkCanvas canvas = recorder.beginRecording(ui.Rect.largest);
        final CkParagraphBuilder builder = CkParagraphBuilder(CkParagraphStyle());
        builder.addText(text);
        final CkParagraph paragraph = builder.build();
        paragraph.layout(const ui.ParagraphConstraints(width: 100));
        canvas.drawRect(
          ui.Rect.fromLTWH(offset.dx, offset.dy, paragraph.width, paragraph.height).inflate(10),
          CkPaint()..color = const ui.Color(0xFF00FF00)
        );
        canvas.drawParagraph(paragraph, offset);
        return recorder.endRecording();
      }

      CkPicture imageToPicture(CkImage image, ui.Offset offset) {
        final CkPictureRecorder recorder = CkPictureRecorder();
        final CkCanvas canvas = recorder.beginRecording(ui.Rect.largest);
        canvas.drawImage(image, offset, CkPaint());
        return recorder.endRecording();
      }

      final CkPicture helloPicture = makeTextPicture('Hello', ui.Offset.zero);

      final CkImage helloImage = helloPicture.toImageSync(100, 100);

      // Calling toByteData is essential to hit the bug.
      await helloImage.toByteData(format: ui.ImageByteFormat.png);

      final LayerSceneBuilder sb = LayerSceneBuilder();
      sb.pushOffset(0, 0);
      sb.addPicture(ui.Offset.zero, helloPicture);
      sb.addPlatformView(0, width: 10, height: 10);

      // The image is rendered after the platform view so that it's rendered into
      // a separate surface, which is what triggers the bug. If the bug is present
      // the image will not appear on the UI.
      sb.addPicture(const ui.Offset(0, 50), imageToPicture(helloImage, ui.Offset.zero));
      sb.pop();

      // The below line should not throw an error.
      rasterizer.draw(sb.build().layerTree);

      await matchGoldenFile('cross_overlay_resources.png', region: const ui.Rect.fromLTRB(0, 0, 100, 100));
    });
  });
}

typedef ParagraphFactory = CkParagraph Function();

void drawTestPicture(CkCanvas canvas) {
  canvas.clear(const ui.Color(0xFFFFFFF));

  canvas.translate(10, 10);

  // Row 1
  canvas.save();

  canvas.save();
  canvas.clipRect(
    const ui.Rect.fromLTRB(0, 0, 45, 45),
    ui.ClipOp.intersect,
    true,
  );
  canvas.clipRRect(
    ui.RRect.fromLTRBR(5, 5, 50, 50, const ui.Radius.circular(8)),
    true,
  );
  canvas.clipPath(
    CkPath()
      ..moveTo(5, 5)
      ..lineTo(25, 5)
      ..lineTo(45, 45)
      ..lineTo(5, 45)
      ..close(),
    true,
  );
  canvas.drawColor(const ui.Color.fromARGB(255, 100, 100, 0), ui.BlendMode.srcOver);
  canvas.restore(); // remove clips

  canvas.translate(60, 0);
  canvas.drawCircle(
    const ui.Offset(30, 25),
    15,
    CkPaint()..color = const ui.Color(0xFF0000AA),
  );

  canvas.translate(60, 0);
  canvas.drawArc(
    const ui.Rect.fromLTRB(10, 20, 50, 40),
    math.pi / 4,
    3 * math.pi / 2,
    true,
    CkPaint()..color = const ui.Color(0xFF00AA00),
  );

  canvas.translate(60, 0);
  canvas.drawImage(
    generateTestImage(),
    const ui.Offset(20, 20),
    CkPaint(),
  );

  canvas.translate(60, 0);
  final ui.RSTransform transform = ui.RSTransform.fromComponents(
    rotation: 0,
    scale: 1,
    anchorX: 0,
    anchorY: 0,
    translateX: 0,
    translateY: 0,
  );
  canvas.drawAtlasRaw(
    CkPaint(),
    generateTestImage(),
    Float32List(4)
      ..[0] = transform.scos
      ..[1] = transform.ssin
      ..[2] = transform.tx + 20
      ..[3] = transform.ty + 20,
    Float32List(4)
      ..[0] = 0
      ..[1] = 0
      ..[2] = 15
      ..[3] = 15,
    Uint32List.fromList(<int>[0x00000000]),
    ui.BlendMode.srcOver,
  );

  canvas.translate(60, 0);
  canvas.drawDRRect(
    ui.RRect.fromLTRBR(0, 0, 40, 30, const ui.Radius.elliptical(16, 8)),
    ui.RRect.fromLTRBR(10, 10, 30, 20, const ui.Radius.elliptical(4, 8)),
    CkPaint(),
  );

  canvas.translate(60, 0);
  canvas.drawImageRect(
    generateTestImage(),
    const ui.Rect.fromLTRB(0, 0, 15, 15),
    const ui.Rect.fromLTRB(10, 10, 40, 40),
    CkPaint(),
  );

  canvas.translate(60, 0);
  canvas.drawImageNine(
    generateTestImage(),
    const ui.Rect.fromLTRB(5, 5, 15, 15),
    const ui.Rect.fromLTRB(10, 10, 50, 40),
    CkPaint(),
  );

  canvas.restore();

  // Row 2
  canvas.translate(0, 60);
  canvas.save();

  canvas.drawLine(ui.Offset.zero, const ui.Offset(40, 30), CkPaint());

  canvas.translate(60, 0);
  canvas.drawOval(
    const ui.Rect.fromLTRB(0, 0, 40, 30),
    CkPaint(),
  );

  canvas.translate(60, 0);
  canvas.save();
  canvas.clipRect(const ui.Rect.fromLTRB(0, 0, 50, 30), ui.ClipOp.intersect, true);
  canvas.drawPaint(CkPaint()..color = const ui.Color(0xFF6688AA));
  canvas.restore();

  canvas.translate(60, 0);
  {
    final CkPictureRecorder otherRecorder = CkPictureRecorder();
    final CkCanvas otherCanvas =
        otherRecorder.beginRecording(const ui.Rect.fromLTRB(0, 0, 40, 20));
    otherCanvas.drawCircle(
      const ui.Offset(30, 15),
      10,
      CkPaint()..color = const ui.Color(0xFFAABBCC),
    );
    canvas.drawPicture(otherRecorder.endRecording());
  }

  canvas.translate(60, 0);
  // TODO(yjbanov): CanvasKit.drawPoints is currently broken
  //                https://github.com/flutter/flutter/issues/71489
  //                But keeping this anyway as it's a good test-case that
  //                will ensure it's fixed when we have the fix.
  canvas.drawPoints(
    CkPaint()
      ..color = const ui.Color(0xFF0000FF)
      ..strokeWidth = 5
      ..strokeCap = ui.StrokeCap.round,
    ui.PointMode.polygon,
    offsetListToFloat32List(const <ui.Offset>[
      ui.Offset(10, 10),
      ui.Offset(20, 10),
      ui.Offset(30, 20),
      ui.Offset(40, 20)
    ]),
  );

  canvas.translate(60, 0);
  canvas.drawRRect(
    ui.RRect.fromLTRBR(0, 0, 40, 30, const ui.Radius.circular(10)),
    CkPaint(),
  );

  canvas.translate(60, 0);
  canvas.drawRect(
    const ui.Rect.fromLTRB(0, 0, 40, 30),
    CkPaint(),
  );

  canvas.translate(60, 0);
  canvas.drawShadow(
    CkPath()..addRect(const ui.Rect.fromLTRB(0, 0, 40, 30)),
    const ui.Color(0xFF00FF00),
    4,
    true,
  );

  canvas.restore();

  // Row 3
  canvas.translate(0, 60);
  canvas.save();

  canvas.drawVertices(
    CkVertices(
      ui.VertexMode.triangleFan,
      const <ui.Offset>[
        ui.Offset(10, 30),
        ui.Offset(30, 50),
        ui.Offset(10, 60),
      ],
    ),
    ui.BlendMode.srcOver,
    CkPaint(),
  );

  canvas.translate(60, 0);
  final int restorePoint = canvas.save();
  for (int i = 0; i < 5; i++) {
    canvas.save();
    canvas.translate(10, 10);
    canvas.drawCircle(ui.Offset.zero, 5, CkPaint());
  }
  canvas.restoreToCount(restorePoint);
  canvas.drawCircle(ui.Offset.zero, 7, CkPaint()..color = const ui.Color(0xFFFF0000));

  canvas.translate(60, 0);
  canvas.drawLine(ui.Offset.zero, const ui.Offset(30, 30), CkPaint());
  canvas.save();
  canvas.rotate(-math.pi / 8);
  canvas.drawLine(ui.Offset.zero, const ui.Offset(30, 30), CkPaint());
  canvas.drawCircle(
      const ui.Offset(30, 30), 7, CkPaint()..color = const ui.Color(0xFF00AA00));
  canvas.restore();

  canvas.translate(60, 0);
  final CkPaint thickStroke = CkPaint()
    ..style = ui.PaintingStyle.stroke
    ..strokeWidth = 20;
  final CkPaint semitransparent = CkPaint()..color = const ui.Color(0x66000000);

  canvas.saveLayer(kDefaultRegion, semitransparent);
  canvas.drawLine(const ui.Offset(10, 10), const ui.Offset(50, 50), thickStroke);
  canvas.drawLine(const ui.Offset(50, 10), const ui.Offset(10, 50), thickStroke);
  canvas.restore();

  canvas.translate(60, 0);
  canvas.saveLayerWithoutBounds(semitransparent);
  canvas.drawLine(const ui.Offset(10, 10), const ui.Offset(50, 50), thickStroke);
  canvas.drawLine(const ui.Offset(50, 10), const ui.Offset(10, 50), thickStroke);
  canvas.restore();

  // To test saveLayerWithFilter we draw three circles with only the middle one
  // blurred using the layer image filter.
  canvas.translate(60, 0);
  canvas.saveLayer(kDefaultRegion, CkPaint());
  canvas.drawCircle(const ui.Offset(30, 30), 10, CkPaint());
  {
    canvas.saveLayerWithFilter(
        kDefaultRegion, ui.ImageFilter.blur(sigmaX: 5, sigmaY: 10));
    canvas.drawCircle(const ui.Offset(10, 10), 10, CkPaint());
    canvas.drawCircle(const ui.Offset(50, 50), 10, CkPaint());
    canvas.restore();
  }
  canvas.restore();

  canvas.translate(60, 0);
  canvas.save();
  canvas.translate(30, 30);
  canvas.scale(2, 1.5);
  canvas.drawCircle(ui.Offset.zero, 10, CkPaint());
  canvas.restore();

  canvas.translate(60, 0);
  canvas.save();
  canvas.translate(30, 30);
  canvas.skew(2, 1.5);
  canvas.drawRect(const ui.Rect.fromLTRB(-10, -10, 10, 10), CkPaint());
  canvas.restore();

  canvas.restore();

  // Row 4
  canvas.translate(0, 60);
  canvas.save();

  canvas.save();
  final Matrix4 matrix = Matrix4.identity();
  matrix.translate(30, 30);
  matrix.scale(2, 1.5);
  canvas.transform(matrix.storage);
  canvas.drawCircle(ui.Offset.zero, 10, CkPaint());
  canvas.restore();

  canvas.translate(60, 0);
  final CkParagraph p = makeSimpleText('Hello', fontSize: 18, color: const ui.Color(0xFF0000AA));
  canvas.drawParagraph(
    p,
    const ui.Offset(10, 20),
  );

  canvas.translate(60, 0);
  canvas.drawPath(
    CkPath()
      ..moveTo(30, 20)
      ..lineTo(50, 50)
      ..lineTo(10, 50)
      ..close(),
    CkPaint()..color = const ui.Color(0xFF0000AA),
  );

  canvas.restore();
}

CkImage generateTestImage() {
  final DomCanvasElement canvas = createDomCanvasElement(width: 20, height: 20);
  final DomCanvasRenderingContext2D ctx = canvas.context2D;
  ctx.fillStyle = '#FF0000';
  ctx.fillRect(0, 0, 10, 10);
  ctx.fillStyle = '#00FF00';
  ctx.fillRect(0, 10, 10, 10);
  ctx.fillStyle = '#0000FF';
  ctx.fillRect(10, 0, 10, 10);
  ctx.fillStyle = '#FF00FF';
  ctx.fillRect(10, 10, 10, 10);
  final Uint8List imageData =
      ctx.getImageData(0, 0, 20, 20).data.buffer.asUint8List();
  final SkImage skImage = canvasKit.MakeImage(
      SkImageInfo(
        width: 20,
        height: 20,
        alphaType: canvasKit.AlphaType.Premul,
        colorType: canvasKit.ColorType.RGBA_8888,
        colorSpace: SkColorSpaceSRGB,
      ),
      imageData,
      4 * 20)!;
  return CkImage(skImage);
}