<?php

/**
 * @package dompdf
 * @link    https://github.com/dompdf/dompdf
 * @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
 */
namespace Dompdf\Css;

use Dompdf\Helpers;

class Color
{
    static $cssColorNames = [
        "aliceblue" => "F0F8FF",
        "antiquewhite" => "FAEBD7",
        "aqua" => "00FFFF",
        "aquamarine" => "7FFFD4",
        "azure" => "F0FFFF",
        "beige" => "F5F5DC",
        "bisque" => "FFE4C4",
        "black" => "000000",
        "blanchedalmond" => "FFEBCD",
        "blue" => "0000FF",
        "blueviolet" => "8A2BE2",
        "brown" => "A52A2A",
        "burlywood" => "DEB887",
        "cadetblue" => "5F9EA0",
        "chartreuse" => "7FFF00",
        "chocolate" => "D2691E",
        "coral" => "FF7F50",
        "cornflowerblue" => "6495ED",
        "cornsilk" => "FFF8DC",
        "crimson" => "DC143C",
        "cyan" => "00FFFF",
        "darkblue" => "00008B",
        "darkcyan" => "008B8B",
        "darkgoldenrod" => "B8860B",
        "darkgray" => "A9A9A9",
        "darkgreen" => "006400",
        "darkgrey" => "A9A9A9",
        "darkkhaki" => "BDB76B",
        "darkmagenta" => "8B008B",
        "darkolivegreen" => "556B2F",
        "darkorange" => "FF8C00",
        "darkorchid" => "9932CC",
        "darkred" => "8B0000",
        "darksalmon" => "E9967A",
        "darkseagreen" => "8FBC8F",
        "darkslateblue" => "483D8B",
        "darkslategray" => "2F4F4F",
        "darkslategrey" => "2F4F4F",
        "darkturquoise" => "00CED1",
        "darkviolet" => "9400D3",
        "deeppink" => "FF1493",
        "deepskyblue" => "00BFFF",
        "dimgray" => "696969",
        "dimgrey" => "696969",
        "dodgerblue" => "1E90FF",
        "firebrick" => "B22222",
        "floralwhite" => "FFFAF0",
        "forestgreen" => "228B22",
        "fuchsia" => "FF00FF",
        "gainsboro" => "DCDCDC",
        "ghostwhite" => "F8F8FF",
        "gold" => "FFD700",
        "goldenrod" => "DAA520",
        "gray" => "808080",
        "green" => "008000",
        "greenyellow" => "ADFF2F",
        "grey" => "808080",
        "honeydew" => "F0FFF0",
        "hotpink" => "FF69B4",
        "indianred" => "CD5C5C",
        "indigo" => "4B0082",
        "ivory" => "FFFFF0",
        "khaki" => "F0E68C",
        "lavender" => "E6E6FA",
        "lavenderblush" => "FFF0F5",
        "lawngreen" => "7CFC00",
        "lemonchiffon" => "FFFACD",
        "lightblue" => "ADD8E6",
        "lightcoral" => "F08080",
        "lightcyan" => "E0FFFF",
        "lightgoldenrodyellow" => "FAFAD2",
        "lightgray" => "D3D3D3",
        "lightgreen" => "90EE90",
        "lightgrey" => "D3D3D3",
        "lightpink" => "FFB6C1",
        "lightsalmon" => "FFA07A",
        "lightseagreen" => "20B2AA",
        "lightskyblue" => "87CEFA",
        "lightslategray" => "778899",
        "lightslategrey" => "778899",
        "lightsteelblue" => "B0C4DE",
        "lightyellow" => "FFFFE0",
        "lime" => "00FF00",
        "limegreen" => "32CD32",
        "linen" => "FAF0E6",
        "magenta" => "FF00FF",
        "maroon" => "800000",
        "mediumaquamarine" => "66CDAA",
        "mediumblue" => "0000CD",
        "mediumorchid" => "BA55D3",
        "mediumpurple" => "9370DB",
        "mediumseagreen" => "3CB371",
        "mediumslateblue" => "7B68EE",
        "mediumspringgreen" => "00FA9A",
        "mediumturquoise" => "48D1CC",
        "mediumvioletred" => "C71585",
        "midnightblue" => "191970",
        "mintcream" => "F5FFFA",
        "mistyrose" => "FFE4E1",
        "moccasin" => "FFE4B5",
        "navajowhite" => "FFDEAD",
        "navy" => "000080",
        "oldlace" => "FDF5E6",
        "olive" => "808000",
        "olivedrab" => "6B8E23",
        "orange" => "FFA500",
        "orangered" => "FF4500",
        "orchid" => "DA70D6",
        "palegoldenrod" => "EEE8AA",
        "palegreen" => "98FB98",
        "paleturquoise" => "AFEEEE",
        "palevioletred" => "DB7093",
        "papayawhip" => "FFEFD5",
        "peachpuff" => "FFDAB9",
        "peru" => "CD853F",
        "pink" => "FFC0CB",
        "plum" => "DDA0DD",
        "powderblue" => "B0E0E6",
        "purple" => "800080",
        "red" => "FF0000",
        "rosybrown" => "BC8F8F",
        "royalblue" => "4169E1",
        "saddlebrown" => "8B4513",
        "salmon" => "FA8072",
        "sandybrown" => "F4A460",
        "seagreen" => "2E8B57",
        "seashell" => "FFF5EE",
        "sienna" => "A0522D",
        "silver" => "C0C0C0",
        "skyblue" => "87CEEB",
        "slateblue" => "6A5ACD",
        "slategray" => "708090",
        "slategrey" => "708090",
        "snow" => "FFFAFA",
        "springgreen" => "00FF7F",
        "steelblue" => "4682B4",
        "tan" => "D2B48C",
        "teal" => "008080",
        "thistle" => "D8BFD8",
        "tomato" => "FF6347",
        "turquoise" => "40E0D0",
        "violet" => "EE82EE",
        "wheat" => "F5DEB3",
        "white" => "FFFFFF",
        "whitesmoke" => "F5F5F5",
        "yellow" => "FFFF00",
        "yellowgreen" => "9ACD32",
    ];

    /**
     * @param array|string|null $color
     * @return array|string|null
     */
    static function parse($color)
    {
        if ($color === null) {
            return null;
        }

        if (is_array($color)) {
            // Assume the array has the right format...
            // FIXME: should/could verify this.
            return $color;
        }

        static $cache = [];

        $color = strtolower($color);

        if (isset($cache[$color])) {
            return $cache[$color];
        }

        if ($color === "transparent") {
            return $cache[$color] = $color;
        }

        if (isset(self::$cssColorNames[$color])) {
            return $cache[$color] = self::getArray(self::$cssColorNames[$color]);
        }

        // https://www.w3.org/TR/css-color-4/#hex-notation
        if (mb_substr($color, 0, 1) === "#") {
            $length = mb_strlen($color);
            $alpha = 1.0;

            // #rgb format
            if ($length === 4) {
                return $cache[$color] = self::getArray($color[1] . $color[1] . $color[2] . $color[2] . $color[3] . $color[3]);
            }

            // #rgba format
            if ($length === 5) {
                if (\ctype_xdigit($color[4])) {
                    $alpha = round(hexdec($color[4] . $color[4])/255, 2);
                }
                return $cache[$color] = self::getArray($color[1] . $color[1] . $color[2] . $color[2] . $color[3] . $color[3], $alpha);
            }

            // #rrggbb format
            if ($length === 7) {
                return $cache[$color] = self::getArray(mb_substr($color, 1, 6));
            }
            
            // #rrggbbaa format
            if ($length === 9) {
                if (\ctype_xdigit(mb_substr($color, 7, 2))) {
                    $alpha = round(hexdec(mb_substr($color, 7, 2))/255, 2);
                }
                return $cache[$color] = self::getArray(mb_substr($color, 1, 6), $alpha);
            }

            return null;
        }

        // rgb( r g b [/α] ) / rgb( r,g,b[,α] ) format and alias rgba()
        // https://www.w3.org/TR/css-color-4/#rgb-functions
        if (mb_substr($color, 0, 4) === "rgb(" || mb_substr($color, 0, 5) === "rgba(") {
            $i = mb_strpos($color, "(");
            $j = mb_strpos($color, ")");

            // Bad color value
            if ($i === false || $j === false) {
                return null;
            }

            $value_decl = trim(mb_substr($color, $i + 1, $j - $i - 1));

            if (mb_strpos($value_decl, ",") === false) {
                // Space-separated values syntax `r g b` or `r g b / α`
                $parts = preg_split("/\s*\/\s*/", $value_decl);
                $triplet = preg_split("/\s+/", $parts[0]);
                $alpha = $parts[1] ?? 1.0;
            } else {
                // Comma-separated values syntax `r, g, b` or `r, g, b, α`
                $parts = preg_split("/\s*,\s*/", $value_decl);
                $triplet = array_slice($parts, 0, 3);
                $alpha = $parts[3] ?? 1.0;
            }

            if (count($triplet) !== 3) {
                return null;
            }

            // Parse alpha value
            if (Helpers::is_percent($alpha)) {
                $alpha = (float) $alpha / 100;
            } else {
                $alpha = (float) $alpha;
            }

            $alpha = max(0.0, min($alpha, 1.0));

            foreach ($triplet as &$c) {
                if (Helpers::is_percent($c)) {
                    $c = round((float) $c * 2.55);
                }
            }

            return $cache[$color] = self::getArray(vsprintf("%02X%02X%02X", $triplet), $alpha);
        }

        // cmyk( c,m,y,k ) format
        // http://www.w3.org/TR/css3-gcpm/#cmyk-colors
        if (mb_substr($color, 0, 5) === "cmyk(") {
            $i = mb_strpos($color, "(");
            $j = mb_strpos($color, ")");

            // Bad color value
            if ($i === false || $j === false) {
                return null;
            }

            $values = explode(",", mb_substr($color, $i + 1, $j - $i - 1));

            if (count($values) != 4) {
                return null;
            }

            $values = array_map(function ($c) {
                return min(1.0, max(0.0, floatval(trim($c))));
            }, $values);

            return $cache[$color] = self::getArray($values);
        }

        // Invalid or unsupported color format
        return null;
    }

    /**
     * @param array|string $color
     * @param float $alpha
     * @return array
     */
    static function getArray($color, $alpha = 1.0)
    {
        $c = [null, null, null, null, "alpha" => $alpha, "hex" => null];

        if (is_array($color)) {
            $c = $color;
            $c["c"] = $c[0];
            $c["m"] = $c[1];
            $c["y"] = $c[2];
            $c["k"] = $c[3];
            $c["alpha"] = $alpha;
            $c["hex"] = "cmyk($c[0],$c[1],$c[2],$c[3])";
        } else {
            if (\ctype_xdigit($color) === false || mb_strlen($color) !== 6) {
                // invalid color value ... expected 6-character hex
                return $c;
            }
            $c[0] = hexdec(mb_substr($color, 0, 2)) / 0xff;
            $c[1] = hexdec(mb_substr($color, 2, 2)) / 0xff;
            $c[2] = hexdec(mb_substr($color, 4, 2)) / 0xff;
            $c["r"] = $c[0];
            $c["g"] = $c[1];
            $c["b"] = $c[2];
            $c["alpha"] = $alpha;
            $c["hex"] = sprintf("#%s%02X", $color, round($alpha * 255));
        }

        return $c;
    }
}
