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/*
========================================================================
SchemaCrawler
http://www.schemacrawler.com
Copyright (c) 2000-2025, Sualeh Fatehi .
All rights reserved.
------------------------------------------------------------------------

SchemaCrawler is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

SchemaCrawler and the accompanying materials are made available under
the terms of the Eclipse Public License v1.0, GNU General Public License
v3 or GNU Lesser General Public License v3.

You may elect to redistribute this code under any of these licenses.

The Eclipse Public License is available at:
http://www.eclipse.org/legal/epl-v10.html

The GNU General Public License v3 and the GNU Lesser General Public
License v3 are available at:
http://www.gnu.org/licenses/

========================================================================
*/

package us.fatehi.utility;

import static java.lang.Math.abs;
import static java.lang.Math.floor;
import java.util.Objects;
import java.util.regex.Pattern;
import static us.fatehi.utility.Utility.requireNotBlank;

/**
 * Color breaks the dependency on java.awt.Color. The AWT comes with a lot of baggage, and is not
 * part of Java Compact Profile 2.
 */
public final class Color {

  public static final Color white = new Color(255, 255, 255);

  private static Pattern htmlColorPattern = Pattern.compile("^#[0-9A-Fa-f]{6}$");

  public static Color fromHexTriplet(final String htmlColor) {
    requireNotBlank(htmlColor, "No color provided");

    if (!htmlColorPattern.matcher(htmlColor).matches()) {
      throw new IllegalArgumentException(String.format("Bad color provided <%s>", htmlColor));
    }

    // Parse color
    final int r = Integer.parseInt(htmlColor.substring(1, 3), 16);
    final int g = Integer.parseInt(htmlColor.substring(3, 5), 16);
    final int b = Integer.parseInt(htmlColor.substring(5, 7), 16);

    return new Color(r, g, b);
  }

  /**
   *  Converting from HSV (HSB in Java) to RGB
   * without using java.awt.Color
   */
  public static Color fromHSV(final float hue, final float saturation, final float value) {
    final float normalizedHue = abs(hue - (float) floor(hue));
    final int h = (int) (normalizedHue * 6);
    final float f = normalizedHue * 6 - h;
    final float p = value * (1 - saturation);
    final float q = value * (1 - f * saturation);
    final float t = value * (1 - (1 - f) * saturation);

    switch (h) {
      case 0:
        return fromRGB(value, t, p);
      case 1:
        return fromRGB(q, value, p);
      case 2:
        return fromRGB(p, value, t);
      case 3:
        return fromRGB(p, q, value);
      case 4:
        return fromRGB(t, p, value);
      case 5:
        return fromRGB(value, p, q);
      default:
        // This case is not expected
        throw new IllegalArgumentException();
    }
  }

  public static Color fromRGB(final int r, final int g, final int b) {
    return new Color(r, g, b);
  }

  private static Color fromRGB(final float r, final float g, final float b) {
    return new Color((int) (r * 255 + 0.5), (int) (g * 255 + 0.5), (int) (b * 255 + 0.5));
  }

  private final int b;
  private final int g;
  private final int r;

  private Color(final int r, final int g, final int b) {
    if (r < 0) {
      this.r = 0;
    } else {
      this.r = Math.min(r, 255);
    }

    if (g < 0) {
      this.g = 0;
    } else {
      this.g = Math.min(g, 255);
    }

    if (b < 0) {
      this.b = 0;
    } else {
      this.b = Math.min(b, 255);
    }
  }

  @Override
  public boolean equals(final Object obj) {
    if (this == obj) {
      return true;
    }
    if ((obj == null) || (getClass() != obj.getClass())) {
      return false;
    }
    final Color other = (Color) obj;
    if ((b != other.b) || (g != other.g)) {
      return false;
    }
    return r == other.r;
  }

  @Override
  public int hashCode() {
    return Objects.hash(b, g, r);
  }

  @Override
  public String toString() {
    final int rgb = (r & 0xFF) << 16 | (g & 0xFF) << 8 | b & 0xFF;

    final String htmlColor = "#" + String.format("%06x", rgb).toUpperCase();
    return htmlColor;
  }
}