packages/flutter/test/painting/colors_test.dart

// Copyright 2015 The Chromium 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/painting.dart';
import 'package:flutter_test/flutter_test.dart';

const double _doubleColorPrecision = 0.01;

void main() {
  test('HSVColor control test', () {
    const HSVColor color = const HSVColor.fromAHSV(0.7, 28.0, 0.3, 0.6);

    expect(color, hasOneLineDescription);
    expect(color.hashCode, equals(const HSVColor.fromAHSV(0.7, 28.0, 0.3, 0.6).hashCode));

    expect(color.withAlpha(0.8), const HSVColor.fromAHSV(0.8, 28.0, 0.3, 0.6));
    expect(color.withHue(123.0), const HSVColor.fromAHSV(0.7, 123.0, 0.3, 0.6));
    expect(color.withSaturation(0.9), const HSVColor.fromAHSV(0.7, 28.0, 0.9, 0.6));
    expect(color.withValue(0.1), const HSVColor.fromAHSV(0.7, 28.0, 0.3, 0.1));

    expect(color.toColor(), const Color(0xb399816b));

    final HSVColor result = HSVColor.lerp(color, const HSVColor.fromAHSV(0.3, 128.0, 0.7, 0.2), 0.25);
    expect(result.alpha, 0.6);
    expect(result.hue, 53.0);
    expect(result.saturation, greaterThan(0.3999));
    expect(result.saturation, lessThan(0.4001));
    expect(result.value, 0.5);
  });

  test('HSVColor hue sweep test', () {
    final List<Color> output = <Color>[];
    for (double hue = 0.0; hue <= 360.0; hue += 36.0) {
      final HSVColor hsvColor = new HSVColor.fromAHSV(1.0, hue, 1.0, 1.0);
      final Color color = hsvColor.toColor();
      output.add(color);
      if (hue != 360.0) {
        // Check that it's reversible.
        expect(
          new HSVColor.fromColor(color),
          within<HSVColor>(distance: _doubleColorPrecision, from: hsvColor),
        );
      }
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xffff0000),
      const Color(0xffff9900),
      const Color(0xffccff00),
      const Color(0xff33ff00),
      const Color(0xff00ff66),
      const Color(0xff00ffff),
      const Color(0xff0066ff),
      const Color(0xff3300ff),
      const Color(0xffcc00ff),
      const Color(0xffff0099),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSVColor saturation sweep test', () {
    final List<Color> output = <Color>[];
    for (double saturation = 0.0; saturation < 1.0; saturation += 0.1) {
      final HSVColor hslColor = new HSVColor.fromAHSV(1.0, 0.0, saturation, 1.0);
      final Color color = hslColor.toColor();
      output.add(color);
      // Check that it's reversible.
      expect(
        new HSVColor.fromColor(color),
        within<HSVColor>(distance: _doubleColorPrecision, from: hslColor),
      );
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xffffffff),
      const Color(0xffffe6e6),
      const Color(0xffffcccc),
      const Color(0xffffb3b3),
      const Color(0xffff9999),
      const Color(0xffff8080),
      const Color(0xffff6666),
      const Color(0xffff4d4d),
      const Color(0xffff3333),
      const Color(0xffff1a1a),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSVColor value sweep test', () {
    final List<Color> output = <Color>[];
    for (double value = 0.0; value < 1.0; value += 0.1) {
      final HSVColor hsvColor = new HSVColor.fromAHSV(1.0, 0.0, 1.0, value);
      final Color color = hsvColor.toColor();
      output.add(color);
      // Check that it's reversible. Discontinuities at the ends for saturation,
      // so we skip those.
      if (value >= _doubleColorPrecision && value <= (1.0 - _doubleColorPrecision)) {
        expect(
          new HSVColor.fromColor(color),
          within<HSVColor>(distance: _doubleColorPrecision, from: hsvColor),
        );
      }
      // output.add(new HSVColor.fromAHSV(1.0, 0.0, 1.0, value).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff000000),
      const Color(0xff1a0000),
      const Color(0xff330000),
      const Color(0xff4d0000),
      const Color(0xff660000),
      const Color(0xff800000),
      const Color(0xff990000),
      const Color(0xffb30000),
      const Color(0xffcc0000),
      const Color(0xffe50000),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSVColor lerps hue correctly.', () {
    final List<Color> output = <Color>[];
    const HSVColor startColor = const HSVColor.fromAHSV(1.0, 0.0, 1.0, 1.0);
    const HSVColor endColor = const HSVColor.fromAHSV(1.0, 360.0, 1.0, 1.0);

    for (double t = -0.5; t < 1.5; t += 0.1) {
      output.add(HSVColor.lerp(startColor, endColor, t).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff00ffff),
      const Color(0xff0066ff),
      const Color(0xff3300ff),
      const Color(0xffcc00ff),
      const Color(0xffff0099),
      const Color(0xffff0000),
      const Color(0xffff9900),
      const Color(0xffccff00),
      const Color(0xff33ff00),
      const Color(0xff00ff66),
      const Color(0xff00ffff),
      const Color(0xff0066ff),
      const Color(0xff3300ff),
      const Color(0xffcc00ff),
      const Color(0xffff0099),
      const Color(0xffff0000),
      const Color(0xffff9900),
      const Color(0xffccff00),
      const Color(0xff33ff00),
      const Color(0xff00ff66),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSVColor lerps saturation correctly.', () {
    final List<Color> output = <Color>[];
    const HSVColor startColor = const HSVColor.fromAHSV(1.0, 0.0, 0.0, 1.0);
    const HSVColor endColor = const HSVColor.fromAHSV(1.0, 0.0, 1.0, 1.0);

    for (double t = -0.1; t < 1.1; t += 0.1) {
      output.add(HSVColor.lerp(startColor, endColor, t).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xffffffff),
      const Color(0xffffffff),
      const Color(0xffffe6e6),
      const Color(0xffffcccc),
      const Color(0xffffb3b3),
      const Color(0xffff9999),
      const Color(0xffff8080),
      const Color(0xffff6666),
      const Color(0xffff4d4d),
      const Color(0xffff3333),
      const Color(0xffff1a1a),
      const Color(0xffff0000),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSVColor lerps value correctly.', () {
    final List<Color> output = <Color>[];
    const HSVColor startColor = const HSVColor.fromAHSV(1.0, 0.0, 1.0, 0.0);
    const HSVColor endColor = const HSVColor.fromAHSV(1.0, 0.0, 1.0, 1.0);

    for (double t = -0.1; t < 1.1; t += 0.1) {
      output.add(HSVColor.lerp(startColor, endColor, t).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff000000),
      const Color(0xff000000),
      const Color(0xff1a0000),
      const Color(0xff330000),
      const Color(0xff4d0000),
      const Color(0xff660000),
      const Color(0xff800000),
      const Color(0xff990000),
      const Color(0xffb30000),
      const Color(0xffcc0000),
      const Color(0xffe50000),
      const Color(0xffff0000),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSLColor control test', () {
    const HSLColor color = const HSLColor.fromAHSL(0.7, 28.0, 0.3, 0.6);

    expect(color, hasOneLineDescription);
    expect(color.hashCode, equals(const HSLColor.fromAHSL(0.7, 28.0, 0.3, 0.6).hashCode));

    expect(color.withAlpha(0.8), const HSLColor.fromAHSL(0.8, 28.0, 0.3, 0.6));
    expect(color.withHue(123.0), const HSLColor.fromAHSL(0.7, 123.0, 0.3, 0.6));
    expect(color.withSaturation(0.9), const HSLColor.fromAHSL(0.7, 28.0, 0.9, 0.6));
    expect(color.withLightness(0.1), const HSLColor.fromAHSL(0.7, 28.0, 0.3, 0.1));

    expect(color.toColor(), const Color(0xb3b8977a));

    final HSLColor result = HSLColor.lerp(color, const HSLColor.fromAHSL(0.3, 128.0, 0.7, 0.2), 0.25);
    expect(result.alpha, 0.6);
    expect(result.hue, 53.0);
    expect(result.saturation, greaterThan(0.3999));
    expect(result.saturation, lessThan(0.4001));
    expect(result.lightness, 0.5);
  });

  test('HSLColor hue sweep test', () {
    final List<Color> output = <Color>[];
    for (double hue = 0.0; hue <= 360.0; hue += 36.0) {
      final HSLColor hslColor = new HSLColor.fromAHSL(1.0, hue, 0.5, 0.5);
      final Color color = hslColor.toColor();
      output.add(color);
      if (hue != 360.0) {
        // Check that it's reversible.
        expect(
          new HSLColor.fromColor(color),
          within<HSLColor>(distance: _doubleColorPrecision, from: hslColor),
        );
      }
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xffbf4040),
      const Color(0xffbf8c40),
      const Color(0xffa6bf40),
      const Color(0xff59bf40),
      const Color(0xff40bf73),
      const Color(0xff40bfbf),
      const Color(0xff4073bf),
      const Color(0xff5940bf),
      const Color(0xffa640bf),
      const Color(0xffbf408c),
      const Color(0xffbf4040),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSLColor saturation sweep test', () {
    final List<Color> output = <Color>[];
    for (double saturation = 0.0; saturation < 1.0; saturation += 0.1) {
      final HSLColor hslColor = new HSLColor.fromAHSL(1.0, 0.0, saturation, 0.5);
      final Color color = hslColor.toColor();
      output.add(color);
      // Check that it's reversible.
      expect(
        new HSLColor.fromColor(color),
        within<HSLColor>(distance: _doubleColorPrecision, from: hslColor),
      );
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff808080),
      const Color(0xff8c7373),
      const Color(0xff996666),
      const Color(0xffa65959),
      const Color(0xffb34d4d),
      const Color(0xffbf4040),
      const Color(0xffcc3333),
      const Color(0xffd92626),
      const Color(0xffe51a1a),
      const Color(0xfff20d0d),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSLColor lightness sweep test', () {
    final List<Color> output = <Color>[];
    for (double lightness = 0.0; lightness < 1.0; lightness += 0.1) {
      final HSLColor hslColor = new HSLColor.fromAHSL(1.0, 0.0, 0.5, lightness);
      final Color color = hslColor.toColor();
      output.add(color);
      // Check that it's reversible. Discontinuities at the ends for saturation,
      // so we skip those.
      if (lightness >= _doubleColorPrecision && lightness <= (1.0 - _doubleColorPrecision)) {
        expect(
          new HSLColor.fromColor(color),
          within<HSLColor>(distance: _doubleColorPrecision, from: hslColor),
        );
      }
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff000000),
      const Color(0xff260d0d),
      const Color(0xff4d1a1a),
      const Color(0xff732626),
      const Color(0xff993333),
      const Color(0xffbf4040),
      const Color(0xffcc6666),
      const Color(0xffd98c8c),
      const Color(0xffe6b3b3),
      const Color(0xfff2d9d9),
      const Color(0xffffffff),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSLColor lerps hue correctly.', () {
    final List<Color> output = <Color>[];
    const HSLColor startColor = const HSLColor.fromAHSL(1.0, 0.0, 0.5, 0.5);
    const HSLColor endColor = const HSLColor.fromAHSL(1.0, 360.0, 0.5, 0.5);

    for (double t = -0.5; t < 1.5; t += 0.1) {
      output.add(HSLColor.lerp(startColor, endColor, t).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff40bfbf),
      const Color(0xff4073bf),
      const Color(0xff5940bf),
      const Color(0xffa640bf),
      const Color(0xffbf408c),
      const Color(0xffbf4040),
      const Color(0xffbf8c40),
      const Color(0xffa6bf40),
      const Color(0xff59bf40),
      const Color(0xff40bf73),
      const Color(0xff40bfbf),
      const Color(0xff4073bf),
      const Color(0xff5940bf),
      const Color(0xffa640bf),
      const Color(0xffbf408c),
      const Color(0xffbf4040),
      const Color(0xffbf8c40),
      const Color(0xffa6bf40),
      const Color(0xff59bf40),
      const Color(0xff40bf73),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSLColor lerps saturation correctly.', () {
    final List<Color> output = <Color>[];
    const HSLColor startColor = const HSLColor.fromAHSL(1.0, 0.0, 0.0, 0.5);
    const HSLColor endColor = const HSLColor.fromAHSL(1.0, 0.0, 1.0, 0.5);

    for (double t = -0.1; t < 1.1; t += 0.1) {
      output.add(HSLColor.lerp(startColor, endColor, t).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff808080),
      const Color(0xff808080),
      const Color(0xff8c7373),
      const Color(0xff996666),
      const Color(0xffa65959),
      const Color(0xffb34d4d),
      const Color(0xffbf4040),
      const Color(0xffcc3333),
      const Color(0xffd92626),
      const Color(0xffe51a1a),
      const Color(0xfff20d0d),
      const Color(0xffff0000),
      const Color(0xffff0000),
    ];
    expect(output, equals(expectedColors));
  });

  test('HSLColor lerps lightness correctly.', () {
    final List<Color> output = <Color>[];
    const HSLColor startColor = const HSLColor.fromAHSL(1.0, 0.0, 0.5, 0.0);
    const HSLColor endColor = const HSLColor.fromAHSL(1.0, 0.0, 0.5, 1.0);

    for (double t = -0.1; t < 1.1; t += 0.1) {
      output.add(HSLColor.lerp(startColor, endColor, t).toColor());
    }
    final List<Color> expectedColors = <Color>[
      const Color(0xff000000),
      const Color(0xff000000),
      const Color(0xff260d0d),
      const Color(0xff4d1a1a),
      const Color(0xff732626),
      const Color(0xff993333),
      const Color(0xffbf4040),
      const Color(0xffcc6666),
      const Color(0xffd98c8c),
      const Color(0xffe6b3b3),
      const Color(0xfff2d9d9),
      const Color(0xffffffff),
      const Color(0xffffffff),
    ];
    expect(output, equals(expectedColors));
  });

  test('ColorSwatch test', () {
    final int color = nonconst(0xFF027223);
    final ColorSwatch<String> greens1 = new ColorSwatch<String>(
      color,
      const <String, Color>{
        '2259 C': const Color(0xFF027223),
        '2273 C': const Color(0xFF257226),
        '2426 XGC': const Color(0xFF00932F),
        '7732 XGC': const Color(0xFF007940),
      },
    );
    final ColorSwatch<String> greens2 = new ColorSwatch<String>(
      color,
      const <String, Color>{
        '2259 C': const Color(0xFF027223),
        '2273 C': const Color(0xFF257226),
        '2426 XGC': const Color(0xFF00932F),
        '7732 XGC': const Color(0xFF007940),
      },
    );
    expect(greens1, greens2);
    expect(greens1.hashCode, greens2.hashCode);
    expect(greens1['2259 C'], const Color(0xFF027223));
    expect(greens1.value, 0xFF027223);
  });
}