From 13bb06083c71921c0f992e2a9f16b7b3668a65d7 Mon Sep 17 00:00:00 2001
From: ma3315865 <ma3315865@outlook.com>
Date: Wed, 18 Dec 2024 11:23:08 +0800
Subject: [PATCH] SetStreamIndex

---
 program.go      | 7 +++++++
 program_test.go | 7 ++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/program.go b/program.go
index 60b3dcc..e8ff9c4 100644
--- a/program.go
+++ b/program.go
@@ -75,6 +75,13 @@ func (p *Program) StreamIndex() *uint {
 	return &u
 }
 
+// https://ffmpeg.org/doxygen/7.0/structAVProgram.html#a7967d41af4812ed61a28762e988c7a02
+func (p *Program) SetStreamIndex(n uint) {
+	if p.c.stream_index != nil {
+		*p.c.stream_index = C.uint(n)
+	}
+}
+
 // https://ffmpeg.org/doxygen/7.0/structAVProgram.html#ae9dab38d4694e3da9cba0f882f4e43d3
 func (p *Program) Metadata() *Dictionary {
 	return newDictionaryFromC(p.c.metadata)
diff --git a/program_test.go b/program_test.go
index 50a604d..19f7ea4 100644
--- a/program_test.go
+++ b/program_test.go
@@ -16,7 +16,6 @@ func TestProgram(t *testing.T) {
 	require.Equal(t, 2, p.ID())
 	p.SetDiscard(DiscardAll)
 	require.Equal(t, DiscardAll, p.Discard())
-	require.Nil(t, p.StreamIndex(), nil)
 	d := NewDictionary()
 	require.NoError(t, d.Set("service_name", "test_service_name", 0))
 	p.SetMetadata(d)
@@ -34,8 +33,14 @@ func TestProgram(t *testing.T) {
 	s := fc.NewStream(nil)
 	s.SetID(2)
 	require.Equal(t, 0, p.NbStreams())
+	require.Nil(t, p.StreamIndex(), nil)
 	p.AddStream(s)
 	require.Equal(t, 1, p.NbStreams())
+	require.Equal(t, uint(0), *p.StreamIndex())
+	var streamIndex uint = 1
+	p.SetStreamIndex(streamIndex)
+	require.Equal(t, streamIndex, *p.StreamIndex())
+	s.SetIndex(int(streamIndex))
 	ss := p.Streams()
 	require.Equal(t, 1, len(ss))
 	require.Equal(t, s.ID(), ss[0].ID())