Cleanup library to be more compliant

README.md

@@ -1,3 +1,30 @@
-# php-base64string
-A small PHP library for dealing with Base64 strings formatted as a data URI/URL.
-This library almost (but does not fully) conforms to RFC 2397.
+# DataUrl
+A small PHP library for dealing with data URLs, which contain a media type and an encoded base64 string.
+
+This library almost (but does not fully) conforms to RFC 2397. It currently does not yet allow `data:,`, which is a data URL with no defined media-type, and zero-length data.
+
+## Install
+```
+composer require neoncitylights/data-url
+```
+
+## Usage
+```php
+<?php
+
+use Neoncitylights\DataUrl\DataUrl;
+
+$dataUrl = DataUrl::newFromString( 'data:text/plain;base64,VGhlIGZpdmUgYm94aW5nIHdpemFyZHMganVtcCBxdWlja2x5Lg==' );
+
+print( $dataUrl->getMediaType()->getEssence() );
+// 'text/plain'
+
+print( $dataUrl->getData() );
+// `VGhlIGZpdmUgYm94aW5nIHdpemFyZHMganVtcCBxdWlja2x5Lg==`
+
+print( $dataUrl->getDecodedValue() );
+// 'The five boxing wizards jump quickly.'
+```
+
+## References
+* Masinter, L., &amp; X. (1998, August). The "data" URL scheme. Retrieved October 30, 2020, from https://tools.ietf.org/html/rfc2397

composer.json

@@ -1,17 +1,25 @@
 {
-	"name": "neoncitylights/base64-string",
+	"name": "neoncitylights/data-url",
 	"authors": [
 		{
 			"name": "Samantha Nguyen"
 		}
 	],
 	"license": "MIT",
-	"description": "Allows working with base 64 strings as entity objects in PHP",
+	"description": "Allows working with data URLs as entity objects in PHP",
+	"keywords": [
+		"data url",
+		"data uri",
+		"rfc 2397"
+	],
 	"autoload": {
 		"psr-4": {
-			"Neoncitylights\\Base64String\\": "src/"
+			"Neoncitylights\\DataUrl\\": "src/"
 		}
 	},
+	"require": {
+		"neoncitylights/media-type": "^1.0"
+	},
 	"require-dev": {
 		"mediawiki/mediawiki-codesniffer": "32.0.0",
 		"mediawiki/minus-x": "1.1.0",

src/DataUrl.php

@@ -0,0 +1,102 @@
+<?php
+
+namespace Neoncitylights\DataUrl;
+
+use Neoncitylights\MediaType\MediaType;
+use function base64_decode;
+use function sprintf;
+use function strlen;
+use function strrchr;
+use function strrpos;
+use function substr;
+
+/**
+ * @see https://tools.ietf.org/html/rfc2397
+ * @license MIT
+ */
+class DataUrl {
+	private const TOKEN_COLON = ';';
+	private const TOKEN_DATA_SCHEME = 'data:';
+	private const TOKEN_BASE64_EXT = ';base64,';
+
+	/** @var MediaType */
+	private $mediaType;
+
+	/** @var string */
+	private $data;
+
+	/** @var string */
+	private $decodedValue;
+
+	/**
+	 * @param MediaType $mediaType
+	 * @param string $data
+	 */
+	public function __construct( MediaType $mediaType, string $data ) {
+		$this->mediaType = $mediaType;
+		$this->data = $data;
+	}
+
+	/**
+	 * Creates a Base64String object from a data URL.
+	 *
+	 * @param string $dataUrl
+	 * @return self|null
+	 */
+	public static function newFromString( string $dataUrl ) : ?self {
+		$stringFromLastColonToken = strrchr( $dataUrl, self::TOKEN_COLON );
+		$stringBeforeBase64 = substr( $dataUrl, 0, strrpos( $dataUrl, self::TOKEN_COLON ) );
+
+		$mediaType = substr( $stringBeforeBase64, strlen( self::TOKEN_DATA_SCHEME ) );
+		$data = substr( $stringFromLastColonToken, strlen( self::TOKEN_BASE64_EXT ) );
+
+		return new self( MediaType::newFromString( $mediaType ), $data );
+	}
+
+	/**
+	 * Gets the media type of the encoded base64 string.
+	 *
+	 * @return MediaType
+	 */
+	public function getMediaType() : MediaType {
+		return $this->mediaType;
+	}
+
+	/**
+	 * Gets the original, encoded base64 string.
+	 *
+	 * @return string
+	 */
+	public function getData() : string {
+		return $this->data;
+	}
+
+	/**
+	 * Gets a decoded value of the base64 string.
+	 *
+	 * @return string
+	 */
+	public function getDecodedValue() : string {
+		if ( $this->decodedValue !== null ) {
+			return $this->decodedValue;
+		}
+
+		$this->decodedValue = base64_decode( $this->data );
+		return $this->decodedValue;
+	}
+
+	/**
+	 * Returns a data URL compliant with RFC 2397.
+	 *
+	 * @return string
+	 */
+	public function __toString() : string {
+		return sprintf(
+			'%s%s%s%s',
+			self::TOKEN_DATA_SCHEME,
+			(string)$this->mediaType,
+			self::TOKEN_BASE64_EXT,
+			$this->data
+		);
+	}
+}