✨ Support attachments

src/Attachment.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace Danjones\FFMpeg;
+
+use FFMpeg\Format\FormatInterface;
+
+class Attachment extends Stream
+{
+    protected string $input = '';
+
+    public function __construct(Map $map, string $file = '')
+    {
+        $this->map = $map;
+        $this->input = $file;
+        // Shouldn't be necessary, but just in case
+        $this->codec = new Format\Copy();
+    }
+
+    public function mime(string $mime): static
+    {
+        return $this->addMetadata('mimetype', $mime);
+    }
+
+    public function setCodec(FormatInterface $codec): static
+    {
+        return $this;
+    }
+
+    protected function parseCodec(): static
+    {
+        return $this;
+    }
+
+    public function saveAttachment(): Map
+    {
+        return $this->saveStream();;
+    }
+
+    public function buildCommand(int $idx = 0): array
+    {
+        $commands    = parent::buildCommand($idx);
+        $commands[0] = '-attach';
+
+        return $commands;
+    }
+}

src/Map.php

@@ -13,6 +13,8 @@ class Map
     protected string $path;
     /** @var Stream[] */
     protected array $streams = [];
+    /** @var Attachment[] */
+    protected array $attachments = [];
     /** @var AbstractProgressListener[] */
     protected array $listeners = [];
 
@@ -35,9 +37,8 @@ class Map
         return $this;
     }
 
-    public function stream(callable $callback = null): Stream|static
+    protected function doStream(Stream $stream, callable $callback = null): Stream|static
     {
-        $stream = new Stream($this);
         if (!$callback) {
             return $stream;
         }
@@ -48,8 +49,24 @@ class Map
         return $this;
     }
 
+    public function stream(callable $callback = null): Stream|static
+    {
+        return $this->doStream(new Stream($this), $callback);
+    }
+
+    public function attach(string $file = '', callable $callback = null): Attachment|static
+    {
+        return $this->doStream(new Attachment($this, $file), $callback);
+    }
+
     public function saveStream(Stream $stream): static
     {
+        if ($stream instanceof Attachment){
+            $this->attachments[] = $stream;
+
+            return $this;
+        }
+
         $this->streams[] = $stream;
         $format = $stream->getCodec();
         if ($format instanceof ProgressableInterface) {
@@ -72,7 +89,9 @@ class Map
     public function buildCommand(): array
     {
         $commands = [];
-        foreach ($this->streams as $idx => $stream) {
+        $streams = $this->streams;
+        array_push($streams, ...$this->attachments);
+        foreach ($streams as $idx => $stream) {
             array_push($commands, ...$stream->buildCommand($idx));
         }
         foreach ($this->metadata as $k => $v) {