+ return ($yiq >= 128) ? $black : $white;
+ }
+
+ /**
+ * Parse any color string into rgb decimal values
+ *
+ * Accepted formats:
+ * Full hex: "#ffffff"
+ * Short hex: "#fff"
+ * Color name "white"
+ * RGB notation: "rgb(255, 255, 255)"
+ *
+ * @param string $color
+ * @return int[]|null
+ * [red, green, blue]
+ */
+ public static function getRgb($color) {
+ $color = str_replace(' ', '', $color);
+ $color = self::nameToHex($color) ?? $color;
+ if (strpos($color, 'rgb(') === 0) {
+ return explode(',', substr($color, 4, strpos($color, ')') - 4));
+ }
+ $color = ltrim($color, '#');
+ if (strlen($color) === 3) {
+ $color = $color[0] . $color[0] . $color[1] . $color[1] . $color[2] . $color[2];
+ }
+ if (!CRM_Utils_Rule::color('#' . $color)) {
+ return NULL;
+ }
+ return [
+ hexdec(substr($color, 0, 2)),
+ hexdec(substr($color, 2, 2)),
+ hexdec(substr($color, 4, 2)),
+ ];
+ }
+
+ /**
+ * Calculate a highlight color from a base color
+ *
+ * @param $color
+ * @return string
+ */
+ public static function getHighlight($color) {
+ $rgb = self::getRgb($color);
+ $avg = array_sum($rgb) / 3;
+ foreach ($rgb as &$v) {
+ if ($avg > 242) {
+ // For very bright values, lower the brightness
+ $v -= 50;
+ }
+ else {
+ // Bump up brightness on a nonlinear curve - darker colors get more of a boost
+ $v = min(255, intval((-.0035 * ($v - 242) ** 2) + 260));
+ }
+ }
+ return self::rgbToHex($rgb);
+ }
+
+ /**
+ * Convert named color (e.g. springgreen) to hex
+ *
+ * @param $colorName
+ * @return string|null
+ */
+ public static function nameToHex($colorName) {
+ if (strpos($colorName, '#') !== FALSE || strpos($colorName, '(') !== FALSE) {
+ return NULL;
+ }
+ if (empty(Civi::$statics[__CLASS__]['names'])) {
+ Civi::$statics[__CLASS__]['names'] = json_decode(file_get_contents(Civi::paths()->getPath(self::COLOR_FILE)), TRUE);
+ }
+ return Civi::$statics[__CLASS__]['names'][strtolower($colorName)] ?? NULL;
+ }
+
+ /**
+ * Converts rgb array to hex string
+ *
+ * @param int[] $rgb
+ * @return string
+ */
+ public static function rgbToHex($rgb) {
+ $ret = '#';
+ foreach ($rgb as $dec) {
+ $ret .= str_pad(dechex($dec), 2, '0', STR_PAD_LEFT);
+ }
+ return $ret;
+ }
+
+ /**
+ * Validate color input and convert it to standard hex notation
+ *
+ * @param string $color
+ * @return bool
+ */
+ public static function normalize(&$color) {
+ $rgb = self::getRgb($color);
+ if ($rgb) {
+ $color = self::rgbToHex($rgb);
+ return TRUE;
+ }
+ return FALSE;