Add interface for GenericData & EncodedImage

src/EncodedImage.php

@@ -2,7 +2,9 @@
 
 namespace Intervention\Image;
 
-class EncodedImage extends GenericData
+use Intervention\Image\Interfaces\EncodedImageInterface;
+
+class EncodedImage extends GenericData implements EncodedImageInterface
 {
     /**
      * Create new instance

src/GenericData.php

@@ -3,8 +3,9 @@
 namespace Intervention\Image;
 
 use Intervention\Image\Exceptions\NotWritableException;
+use Intervention\Image\Interfaces\GenericDataInterface;
 
-class GenericData
+class GenericData implements GenericDataInterface
 {
     /**
      * Create new instance

src/Interfaces/EncodedImageInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Intervention\Image\Interfaces;
+
+interface EncodedImageInterface extends GenericDataInterface
+{
+    /**
+     * Return Media (MIME) Type of encoded image
+     *
+     * @return string
+     */
+    public function mimetype(): string;
+
+    /**
+     * Turn encoded image into DataUri format
+     *
+     * @return string
+     */
+    public function toDataUri(): string;
+}

src/Interfaces/GenericDataInterface.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace Intervention\Image\Interfaces;
+
+interface GenericDataInterface
+{
+    /**
+     * Save data in given path in file system
+     *
+     * @param  string $filepath
+     * @return void
+     */
+    public function save(string $filepath): void;
+
+    /**
+     * Create file pointer from encoded data
+     *
+     * @return resource
+     */
+    public function toFilePointer();
+
+    /**
+     * Return size in bytes
+     *
+     * @return int
+     */
+    public function size(): int;
+
+    /**
+     * Turn encoded data into string
+     *
+     * @return string
+     */
+    public function toString(): string;
+
+    /**
+     * Cast encoded data into string
+     *
+     * @return string
+     */
+    public function __toString(): string;
+}