refactor: use enums for representing tokens (PHP 8.1)

composer.json

@@ -29,7 +29,8 @@
 		}
 	},
 	"require": {
-		"neoncitylights/media-type": "^1.0"
+		"neoncitylights/media-type": "^1.0",
+		"php": ">= 8.1"
 	},
 	"require-dev": {
 		"mediawiki/mediawiki-codesniffer": "43.0.0",

src/DataUrl.php

@@ -10,7 +10,7 @@
  * @see https://tools.ietf.org/html/rfc2397
  * @license MIT
  */
-class DataUrl implements DataUrlToken {
+class DataUrl {
 	/** @var MediaType */
 	private $mediaType;
 
@@ -61,10 +61,10 @@ public function getDecodedValue(): string {
 	public function __toString(): string {
 		return sprintf(
 			'%s%s%s%s%s',
-			self::TOKEN_DATA_SCHEME,
+			Token::UriScheme->value,
 			(string)$this->mediaType,
-			self::TOKEN_BASE64_EXT,
-			self::TOKEN_COMMA,
+			Token::Base64Ext->value,
+			Token::Comma->value,
 			$this->data
 		);
 	}

src/DataUrlParser.php

@@ -20,7 +20,7 @@
  * @see https://tools.ietf.org/html/rfc2397
  * @license MIT
  */
-class DataUrlParser implements DataUrlToken {
+class DataUrlParser {
 	/**
 	 * @param string $dataUrl
 	 * @return DataUrl
@@ -36,15 +36,15 @@ public function parse( string $dataUrl ): DataUrl {
 			);
 		}
 
-		if ( strpos( $trimmedDataUrl, self::TOKEN_DATA_SCHEME ) === false ) {
+		if ( strpos( $trimmedDataUrl, Token::UriScheme->value ) === false ) {
 			throw new InvalidDataUrlSyntaxException(
 				"A valid data URL requires including a \"data:\" scheme.",
 				$dataUrl
 			);
 		}
 
-		$urlPath = substr( $trimmedDataUrl, strlen( self::TOKEN_DATA_SCHEME ) );
-		$lastCommaIndex = strrpos( $urlPath, self::TOKEN_COMMA );
+		$urlPath = substr( $trimmedDataUrl, strlen( Token::UriScheme->value ) );
+		$lastCommaIndex = strrpos( $urlPath, Token::Comma->value );
 		if ( $lastCommaIndex === false ) {
 			throw new InvalidDataUrlSyntaxException(
 				"A valid data URL requires including a comma character.",
@@ -66,7 +66,7 @@ public function parse( string $dataUrl ): DataUrl {
 	 * @return MediaType
 	 */
 	private function parseMediaTypeAndBase64( string $content ): MediaType {
-		$base64ExtIndex = strrpos( $content, self::TOKEN_BASE64_EXT );
+		$base64ExtIndex = strrpos( $content, Token::Base64Ext->value );
 		if ( is_int( $base64ExtIndex ) ) {
 			$mediaTypeString = substr( $content, 0, $base64ExtIndex );
 			return $this->getMediaType( $mediaTypeString );

src/Token.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Neoncitylights\DataUrl;
+
+/**
+ * @internal
+ * @license MIT
+ */
+enum Token: string {
+	case Base64Ext = ';base64';
+	case UriScheme = 'data:';
+	case Comma = ',';
+}