From 94f55d5922ca4cf3bb0d30ca2b09181d7106c44a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Torbjo=CC=88rn=20Einarsson?= <torbjorn@einarssons.se>
Date: Sun, 10 Nov 2024 08:23:12 +0100
Subject: [PATCH] feat: extension of CreateHdlr

---
 CHANGELOG.md     |  2 ++
 mp4/hdlr.go      | 11 ++++++-----
 mp4/hdlr_test.go | 48 ++++++++++++++++++++++++++++++++++++++----------
 3 files changed, 46 insertions(+), 15 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 401db8cb..c911c7a2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - CreatePrftBox now takes flags parameter
 - PrftBox Info output
 - Removed ReplaceChild method of StsdBox
+- CreateHdlr name for timed metadata
 
 ### Added
 
@@ -19,6 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Constants for PrftBox flags
 - Unittest to all commands and examples
 
+
 ### Fixed
 
 - Allow missing optional DecoderSpecificInfo
diff --git a/mp4/hdlr.go b/mp4/hdlr.go
index 54110a87..1e6047bb 100644
--- a/mp4/hdlr.go
+++ b/mp4/hdlr.go
@@ -12,9 +12,8 @@ import (
 // Contained in: Media Box (mdia) or Meta Box (meta)
 //
 // This box describes the type of data contained in the trak.
-// HandlerType can be : "vide" (video track), "soun" (audio track), "subt" (subtitle track)
-// Other types are: "hint" (hint track), "meta" (timed Metadata track), "auxv" (auxiliary video track).
-// clcp (Closed Captions (QuickTime))
+// Most common hnadler types are: "vide" (video track), "soun" (audio track), "subt" (subtitle track),
+// "text" (text track). "meta" (timed Metadata track), clcp (Closed Captions (QuickTime))
 type HdlrBox struct {
 	Version              byte
 	Flags                uint32
@@ -40,16 +39,18 @@ func CreateHdlr(mediaOrHdlrType string) (*HdlrBox, error) {
 	case "text", "wvtt":
 		hdlr.HandlerType = "text"
 		hdlr.Name = "mp4ff text handler"
+	case "meta":
+		hdlr.HandlerType = "meta"
+		hdlr.Name = "mp4ff timed metadata handler"
 	case "clcp":
 		hdlr.HandlerType = "subt"
 		hdlr.Name = "mp4ff closed captions handler"
 	default:
 		if len(mediaOrHdlrType) != 4 {
-			return nil, fmt.Errorf("unknown media or hdlr type %s", mediaOrHdlrType)
+			return nil, fmt.Errorf("handler type is not four characters: %s", mediaOrHdlrType)
 		}
 		hdlr.HandlerType = mediaOrHdlrType
 		hdlr.Name = fmt.Sprintf("mp4ff %s handler", mediaOrHdlrType)
-
 	}
 	return hdlr, nil
 }
diff --git a/mp4/hdlr_test.go b/mp4/hdlr_test.go
index af06d1e6..2b514381 100644
--- a/mp4/hdlr_test.go
+++ b/mp4/hdlr_test.go
@@ -7,19 +7,47 @@ import (
 )
 
 func TestHdlr(t *testing.T) {
-	mediaTypes := []string{"video", "audio", "subtitle"}
 
-	for _, m := range mediaTypes {
-		hdlr, err := CreateHdlr(m)
-		assertNoError(t, err)
-		boxDiffAfterEncodeAndDecode(t, hdlr)
+	cases := []struct {
+		mediaType     string
+		handlerType   string
+		handlerName   string
+		expectedError string
+	}{
+		{"video", "vide", "mp4ff video handler", ""},
+		{"vide", "vide", "mp4ff video handler", ""},
+		{"audio", "soun", "mp4ff audio handler", ""},
+		{"soun", "soun", "mp4ff audio handler", ""},
+		{"subtitle", "subt", "mp4ff subtitle handler", ""},
+		{"text", "text", "mp4ff text handler", ""},
+		{"wvtt", "text", "mp4ff text handler", ""},
+		{"meta", "meta", "mp4ff timed metadata handler", ""},
+		{"clcp", "subt", "mp4ff closed captions handler", ""},
+		{"roses", "", "", "handler type is not four characters: roses"},
+		{"auxv", "auxv", "mp4ff auxv handler", ""},
 	}
 
-	for _, m := range mediaTypes {
-		hdlr, err := CreateHdlr(m)
-		hdlr.LacksNullTermination = true
-		assertNoError(t, err)
-		boxDiffAfterEncodeAndDecode(t, hdlr)
+	for _, c := range cases {
+		t.Run(c.mediaType, func(t *testing.T) {
+			hdlr, err := CreateHdlr(c.mediaType)
+			if c.expectedError != "" {
+				if err == nil {
+					t.Errorf("Expected error %s, but got nil", c.expectedError)
+				} else if err.Error() != c.expectedError {
+					t.Errorf("Expected error %s, but got %s", c.expectedError, err.Error())
+				}
+				return
+			}
+			if hdlr.HandlerType != c.handlerType {
+				t.Errorf("Expected handler type %s, but got %s", c.handlerType, hdlr.HandlerType)
+			}
+			if hdlr.Name != c.handlerName {
+				t.Errorf("Expected handler name %s, but got %s", c.handlerName, hdlr.Name)
+			}
+			boxDiffAfterEncodeAndDecode(t, hdlr)
+			hdlr.LacksNullTermination = true
+			boxDiffAfterEncodeAndDecode(t, hdlr)
+		})
 	}
 }