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    <h3>Editing: AnsiColorMode.php</h3>
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/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Console\Output;

use Symfony\Component\Console\Exception\InvalidArgumentException;

/**
 * @author Fabien Potencier &lt;fabien@symfony.com&gt;
 * @author Julien Boudry &lt;julien@condorcet.vote&gt;
 */
enum AnsiColorMode
{
    /*
     * Classical 4-bit Ansi colors, including 8 classical colors and 8 bright color. Output syntax is &quot;ESC[${foreGroundColorcode};${backGroundColorcode}m&quot;
     * Must be compatible with all terminals and it's the minimal version supported.
     */
    case Ansi4;

    /*
     * 8-bit Ansi colors (240 differents colors + 16 duplicate color codes, ensuring backward compatibility).
     * Output syntax is: &quot;ESC[38;5;${foreGroundColorcode};48;5;${backGroundColorcode}m&quot;
     * Should be compatible with most terminals.
     */
    case Ansi8;

    /*
     * 24-bit Ansi colors (RGB).
     * Output syntax is: &quot;ESC[38;2;${foreGroundColorcodeRed};${foreGroundColorcodeGreen};${foreGroundColorcodeBlue};48;2;${backGroundColorcodeRed};${backGroundColorcodeGreen};${backGroundColorcodeBlue}m&quot;
     * May be compatible with many modern terminals.
     */
    case Ansi24;

    /**
     * Converts an RGB hexadecimal color to the corresponding Ansi code.
     */
    public function convertFromHexToAnsiColorCode(string $hexColor): string
    {
        $hexColor = str_replace('#', '', $hexColor);

        if (3 === \strlen($hexColor)) {
            $hexColor = $hexColor[0].$hexColor[0].$hexColor[1].$hexColor[1].$hexColor[2].$hexColor[2];
        }

        if (6 !== \strlen($hexColor)) {
            throw new InvalidArgumentException(sprintf('Invalid &quot;#%s&quot; color.', $hexColor));
        }

        $color = hexdec($hexColor);

        $r = ($color &gt;&gt; 16) &amp; 255;
        $g = ($color &gt;&gt; 8) &amp; 255;
        $b = $color &amp; 255;

        return match ($this) {
            self::Ansi4 =&gt; (string) $this-&gt;convertFromRGB($r, $g, $b),
            self::Ansi8 =&gt; '8;5;'.((string) $this-&gt;convertFromRGB($r, $g, $b)),
            self::Ansi24 =&gt; sprintf('8;2;%d;%d;%d', $r, $g, $b)
        };
    }

    private function convertFromRGB(int $r, int $g, int $b): int
    {
        return match ($this) {
            self::Ansi4 =&gt; $this-&gt;degradeHexColorToAnsi4($r, $g, $b),
            self::Ansi8 =&gt; $this-&gt;degradeHexColorToAnsi8($r, $g, $b),
            default =&gt; throw new InvalidArgumentException(&quot;RGB cannot be converted to {$this-&gt;name}.&quot;)
        };
    }

    private function degradeHexColorToAnsi4(int $r, int $g, int $b): int
    {
        if (0 === round($this-&gt;getSaturation($r, $g, $b) / 50)) {
            return 0;
        }

        return (int) ((round($b / 255) &lt;&lt; 2) | (round($g / 255) &lt;&lt; 1) | round($r / 255));
    }

    private function getSaturation(int $r, int $g, int $b): int
    {
        $r = $r / 255;
        $g = $g / 255;
        $b = $b / 255;
        $v = max($r, $g, $b);

        if (0 === $diff = $v - min($r, $g, $b)) {
            return 0;
        }

        return (int) ((int) $diff * 100 / $v);
    }

    /**
     * Inspired from https://github.com/ajalt/colormath/blob/e464e0da1b014976736cf97250063248fc77b8e7/colormath/src/commonMain/kotlin/com/github/ajalt/colormath/model/Ansi256.kt code (MIT license).
     */
    private function degradeHexColorToAnsi8(int $r, int $g, int $b): int
    {
        if ($r === $g &amp;&amp; $g === $b) {
            if ($r &lt; 8) {
                return 16;
            }

            if ($r &gt; 248) {
                return 231;
            }

            return (int) round(($r - 8) / 247 * 24) + 232;
        } else {
            return 16 +
                    (36 * (int) round($r / 255 * 5)) +
                    (6 * (int) round($g / 255 * 5)) +
                    (int) round($b / 255 * 5);
        }
    }
}
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