stream/mts: starting to work out meta logistics in encoder.go and added incomplete AddDescriptor function in psi package

stream/mts/encoder.go

@@ -82,43 +82,6 @@ var (
 			},
 		},
 	}
-
-	// standardPmtTimeLocation is a standard PMT with time and location
-	// descriptors, but time and location fields zeroed out.
-	standardPmtTimeLocation = psi.PSI{
-		Pf:  0x00,
-		Tid: 0x02,
-		Ssi: true,
-		Sl:  0x3e,
-		Tss: &psi.TSS{
-			Tide: 0x01,
-			V:    0,
-			Cni:  true,
-			Sn:   0,
-			Lsn:  0,
-			Sd: &psi.PMT{
-				Pcrpid: 0x0100,
-				Pil:    psi.PmtTimeLocationPil,
-				Pd: []psi.Desc{
-					{
-						Dt: psi.TimeDescTag,
-						Dl: psi.TimeDataSize,
-						Dd: make([]byte, psi.TimeDataSize),
-					},
-					{
-						Dt: psi.LocationDescTag,
-						Dl: psi.LocationDataSize,
-						Dd: make([]byte, psi.LocationDataSize),
-					},
-				},
-				Essd: &psi.ESSD{
-					St:   0x1b,
-					Epid: 0x0100,
-					Esil: 0x00,
-				},
-			},
-		},
-	}
 )
 
 const (
@@ -162,13 +125,24 @@ func (tl *timeLocation) Location() string {
 	return l
 }
 
+func updateMeta(b []byte) error {
+	var p psi.PSIBytes
+	p = b
+	// TODO: get length of meta data and format appropriately
+	metaLen := 0
+	metaData := ""
+
+	p.AddDescriptor(psi.MetadataTag, metaLen, metaData)
+	return nil
+}
+
 // MetData will hold time and location data which may be set externally if
 // this data is available. It is then inserted into mpegts packets outputted.
 var MetaData timeLocation
 
 var (
 	patTable = standardPat.Bytes()
-	pmtTable = standardPmtTimeLocation.Bytes()
+	pmtTable = standardPmt.Bytes()
 )
 
 // Time related constants.
@@ -283,15 +257,7 @@ func (e *Encoder) writePSI() error {
 		return err
 	}
 
-	// Update pmt table time and location.
-	err = psi.UpdateTime(pmtTable, MetaData.TimeStamp())
-	if err != nil {
-		return err
-	}
-	err = psi.UpdateLocation(pmtTable, MetaData.Location())
-	if err != nil {
-		return nil
-	}
+	updateMeta(pmtTable)
 
 	// Create mts packet from pmt table.
 	pmtPkt := Packet{

stream/mts/psi/psi.go

@@ -68,6 +68,14 @@ const (
 	crcSize          = 4
 )
 
+const MetadataTag = 0x26
+
+type PSIBytes []byte
+
+func (p *PSIBytes) AddDescriptor(tag, len int, data string) {
+
+}
+
 // Program specific information
 type PSI struct {
 	Pf  byte   // Point field