Added new functions.

writer/pkg/storage/file.go

@@ -399,39 +399,79 @@ func FileBytes(id, res, file string) (int64, error) {
 	return size, nil
 }
 
-// GetHeader
-func GetHeader(id, res, file string) ([]string, error) {
+// GetDurAndTracks reads .insit file and returns duration and tracks of the file.
+func GetDurAndTracks(id, res, file string) (int, map[string]string, error) {
 	// Open file for reading.
 	f, err := os.Open(fmt.Sprintf("%s/%s/%s/%s", config.DirData, id, res, file))
 	if err != nil {
-		return nil, errors.New("opening file error for file: " + err.Error())
+		return 0, nil, errors.New("opening file error for file: " + err.Error())
 	}
 	defer f.Close()
 
 	// Read StreamID.
 	var streamIDLen int32
 	if err := binary.Read(f, binary.LittleEndian, &streamIDLen); err != nil {
-		return nil, errors.New("reading StreamID length error: " + err.Error())
+		return 0, nil, errors.New("reading StreamID length error: " + err.Error())
 	}
 	streamIDBytes := make([]byte, streamIDLen)
 	if _, err := io.ReadFull(f, streamIDBytes); err != nil {
-		return nil, errors.New("reading StreamID error: " + err.Error())
+		return 0, nil, errors.New("reading StreamID error: " + err.Error())
 	}
 
 	// Read header of the file.
 	var segLen int32
 	if err := binary.Read(f, binary.LittleEndian, &segLen); err != nil {
-		return nil, errors.New("reading header length error: " + err.Error())
+		return 0, nil, errors.New("reading header length error: " + err.Error())
 	}
 	segData := make([]byte, segLen)
 	if _, err := io.ReadFull(f, segData); err != nil {
-		return nil, errors.New("reading header error: " + err.Error())
+		return 0, nil, errors.New("reading header error: " + err.Error())
 	}
 	headerReader := bytes.NewReader(segData)
 	headerSeg, err := ReadHeaderSegment(headerReader)
 	if err != nil {
-		return nil, errors.New("reading header error: " + err.Error())
+		return 0, nil, errors.New("reading header error: " + err.Error())
 	}
+
+	// Parse duration of a segment.
+	per, err := strconv.Atoi(headerSeg.Duration)
+	if err != nil {
+		return 0, nil, errors.New("parsing duration error: " + err.Error())
+	}
+
+	tracks := make(map[string]string, 2)
+
+	for {
+		// Read segments length.
+		var segLen int32
+		err := binary.Read(f, binary.LittleEndian, &segLen)
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return 0, nil, errors.New("read segments length error: " + err.Error())
+		}
+		// Read segments data.
+		segData = make([]byte, segLen)
+		if _, err := io.ReadFull(f, segData); err != nil {
+			return 0, nil, errors.New("read segments error: " + err.Error())
+		}
+		packetReader := bytes.NewReader(segData)
+		packets, err := ReadPacketSegment(packetReader)
+		if err != nil {
+			return 0, nil, errors.New("func readPacketSegment error: " + err.Error())
+		}
+
+		for _, pkt := range packets {
+			switch pkt.Type {
+			case PacketTypeH264:
+				tracks["video"] = "H264"
+			case PacketTypeLPCM:
+				tracks["audio"] = "LPCM"
+			}
+		}
+	}
+	return per, tracks, nil
 }
 
 // readString reads string length and then reads string data.