From d561bdf7ed80002c453b50ff22b395e0d28dc884 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Wala?= <lukaszpwala@gmail.com>
Date: Wed, 22 May 2024 17:33:13 +0200
Subject: [PATCH] Add SDES `RtpStreamId` and `RepairedRtpStreamId` item types

---
 README.md                                     |  1 +
 .../packet/source_description/chunk/item.ex   |  6 +++++
 .../source_description/chunk/item_test.exs    | 26 ++++++++++++-------
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/README.md b/README.md
index a4690d5..b7d5f92 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@ Implements packet types from:
 - [RFC 3550 - RTP: A Transport Protocol for Real-Time Applications](https://datatracker.ietf.org/doc/html/rfc3550)
 - [RFC 4585 - Extended RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/AVPF)](https://datatracker.ietf.org/doc/html/rfc4585)
 - [RFC 5104 - Codec Control Messages in the RTP Audio-Visual Profile with Feedback (AVPF)](https://datatracker.ietf.org/doc/html/rfc5104)
+- [RFC 8852 - RTP Stream Identifier Source Description (SDES)](https://datatracker.ietf.org/doc/html/rfc8852)
 - [RTP Extensions for Transport-wide Congestion Control](https://datatracker.ietf.org/doc/html/draft-holmer-rmcat-transport-wide-cc-extensions-01)
 
 For complete list of supported packet types, refer to the [documentation](https://hexdocs.pm/ex_rtcp/readme.html).
diff --git a/lib/ex_rtcp/packet/source_description/chunk/item.ex b/lib/ex_rtcp/packet/source_description/chunk/item.ex
index 03dd381..8b5471c 100644
--- a/lib/ex_rtcp/packet/source_description/chunk/item.ex
+++ b/lib/ex_rtcp/packet/source_description/chunk/item.ex
@@ -18,6 +18,8 @@ defmodule ExRTCP.Packet.SourceDescription.Chunk.Item do
           | :note
           | :priv
           | :mid
+          | :rtp_stream_id
+          | :repaired_rtp_stream_id
 
   @typedoc """
   Struct representing item contained by chunks in Source Description RTCP packets.
@@ -48,6 +50,8 @@ defmodule ExRTCP.Packet.SourceDescription.Chunk.Item do
   defp type_to_id(:tool), do: 6
   defp type_to_id(:note), do: 7
   defp type_to_id(:priv), do: 8
+  defp type_to_id(:rtp_stream_id), do: 12
+  defp type_to_id(:repaired_rtp_stream_id), do: 13
   defp type_to_id(:mid), do: 15
 
   @doc false
@@ -72,6 +76,8 @@ defmodule ExRTCP.Packet.SourceDescription.Chunk.Item do
   defp id_to_type(6), do: :tool
   defp id_to_type(7), do: :note
   defp id_to_type(8), do: :priv
+  defp id_to_type(12), do: :rtp_stream_id
+  defp id_to_type(13), do: :repaired_rtp_stream_id
   defp id_to_type(15), do: :mid
   defp id_to_type(_other), do: nil
 end
diff --git a/test/ex_rtcp/packet/source_description/chunk/item_test.exs b/test/ex_rtcp/packet/source_description/chunk/item_test.exs
index 39a9ad1..9ef8eac 100644
--- a/test/ex_rtcp/packet/source_description/chunk/item_test.exs
+++ b/test/ex_rtcp/packet/source_description/chunk/item_test.exs
@@ -28,11 +28,15 @@ defmodule ExRTCP.Packet.SourceDescription.Chunk.ItemTest do
       end
     end
 
-    test "MID item" do
-      mid = "1234"
-      mid_len = byte_size(mid)
-      item = %Item{type: :mid, text: mid}
-      assert <<15, mid_len, mid::binary>> == Item.encode(item)
+    test "non-RFC 3550 item types" do
+      types = [rtp_stream_id: 12, repaired_rtp_stream_id: 13, mid: 15]
+
+      for {item_type, item_id} <- types do
+        text = "123"
+        text_len = byte_size(text)
+        item = %Item{type: item_type, text: text}
+        assert <<item_id, text_len, text::binary>> == Item.encode(item)
+      end
     end
   end
 
@@ -57,11 +61,15 @@ defmodule ExRTCP.Packet.SourceDescription.Chunk.ItemTest do
       end
     end
 
-    test "MID item" do
-      mid = <<1, 2, 3>>
-      item = <<15, byte_size(mid), mid::binary>>
+    test "non-RFC 3550 item types" do
+      types = [rtp_stream_id: 12, repaired_rtp_stream_id: 13, mid: 15]
 
-      assert {:ok, %Item{type: :mid, text: ^mid}, <<>>} = Item.decode(item)
+      for {item_type, item_id} <- types do
+        text = "123"
+        text_len = byte_size(text)
+        item = <<item_id, text_len, text::binary>>
+        assert {:ok, %Item{type: ^item_type, text: ^text}, <<>>} = Item.decode(item)
+      end
     end
 
     test "invalid item" do