Added Radio.ID and refactored the Stats interface

protocol/aprs/_attic/position.go

@@ -0,0 +1,219 @@
+package aprs
+
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	ErrLatitude  = errors.New("aprs: invalid latitude")
+	ErrLongitude = errors.New("aprs: invalid longitude")
+)
+
+// Latitude is the north-south position. Positive values are North, negative are South.
+type Latitude float64
+
+func LatitudeFromDMH(degrees, minutes, hundreths int, north bool) Latitude {
+	v := float64(degrees) + float64(minutes)/60 + float64(hundreths)/6000
+
+	for v > 90 {
+		v -= 180
+	}
+	for v < -90 {
+		v += 180
+	}
+
+	if north {
+		return Latitude(v)
+	}
+	return -Latitude(v)
+}
+
+func (lat Latitude) DMH() (degrees, minutes, hundreths int, north bool) {
+	degrees = int(lat)
+	minutes = int((float64(lat) - float64(degrees)) * 60)
+	hundreths = int((float64(lat) - float64(degrees) - float64(minutes)/60) * 6000)
+
+	if hundreths == 100 {
+		hundreths = 0
+		minutes += 1
+	}
+
+	if minutes == 60 {
+		minutes = 0
+		degrees += 1
+	}
+
+	north = lat >= 0
+	return
+}
+
+func (lat *Latitude) ParseCompressed(b []byte) error {
+	if len(b) != 4 {
+		return ErrLatitude
+	}
+
+	n, err := base91Decode(string(b))
+	if err != nil {
+		return err
+	}
+
+	*lat = Latitude(90 - float64(n)/380926)
+	return nil
+}
+
+func (lat *Latitude) ParseUncompressed(b []byte) error {
+	if len(b) != 8 || b[4] != '.' {
+		return ErrLatitude
+	}
+
+	var north bool
+	switch b[7] {
+	case 'N':
+		north = true
+	case 'S':
+		north = false
+	default:
+		return ErrLatitude
+	}
+
+	var (
+		degrees, minutes, hundreths int
+		err                         error
+	)
+	if degrees, err = parseBytesWithSpaces(b[0:2]); err != nil {
+		return err
+	}
+	if minutes, err = parseBytesWithSpaces(b[2:4]); err != nil {
+		return err
+	}
+	if hundreths, err = parseBytesWithSpaces(b[5:7]); err != nil {
+		return err
+	}
+
+	*lat = LatitudeFromDMH(degrees, minutes, hundreths, north)
+
+	return nil
+}
+
+func (lat Latitude) Compressed(b []byte) {
+	v := int((90 - float64(lat)) * 380926.0)
+	base91Encode(b, v)
+}
+
+func (lat Latitude) Uncompressed(b []byte) {
+	var (
+		degrees, minutes, hundreths, north = lat.DMH()
+		v                                  = fmt.Sprintf("%02d%02d.%02d", degrees, minutes, hundreths)
+	)
+	if north {
+		v += "N"
+	} else {
+		v += "S"
+	}
+	copy(b, []byte(b))
+}
+
+// Longitude is the east-west position. Positive values are East, negative are West.
+type Longitude float64
+
+func LongitudeFromDMH(degrees, minutes, hundreths int, east bool) Longitude {
+	v := float64(degrees) + float64(minutes)/60 + float64(hundreths)/6000
+
+	for v > 180 {
+		v -= 360
+	}
+	for v < -180 {
+		v += 360
+	}
+
+	if east {
+		return Longitude(v)
+	}
+	return -Longitude(v)
+}
+
+func (long Longitude) DMH() (degrees, minutes, hundreths int, east bool) {
+	degrees = int(long)
+	minutes = int((float64(long) - float64(degrees)) * 60)
+	hundreths = int((float64(long) - float64(degrees) - float64(minutes)/60) * 6000)
+
+	if hundreths == 100 {
+		hundreths = 0
+		minutes += 1
+	}
+
+	if minutes == 60 {
+		minutes = 0
+		degrees += 1
+	}
+
+	east = long >= 0
+	return
+}
+
+func (long *Longitude) ParseCompressed(b []byte) error {
+	if len(b) != 4 {
+		return ErrLatitude
+	}
+
+	n, err := base91Decode(string(b))
+	if err != nil {
+		return err
+	}
+
+	*long = Longitude(float64(n)/190463.0 - 180)
+	return nil
+}
+
+func (long *Longitude) ParseUncompressed(b []byte) error {
+	if len(b) != 9 || b[5] != '.' {
+		return ErrLongitude
+	}
+
+	var east bool
+	switch b[8] {
+	case 'E':
+		east = true
+	case 'W':
+		east = false
+	default:
+		return ErrLongitude
+	}
+
+	var (
+		degrees, minutes, hundreths int
+		err                         error
+	)
+	if degrees, err = parseBytesWithSpaces(b[0:3]); err != nil {
+		return err
+	}
+	if minutes, err = parseBytesWithSpaces(b[3:5]); err != nil {
+		return err
+	}
+	if hundreths, err = parseBytesWithSpaces(b[6:8]); err != nil {
+		return err
+	}
+
+	*long = LongitudeFromDMH(degrees, minutes, hundreths, east)
+
+	return nil
+}
+
+func (long Longitude) Compressed(b []byte) {
+	v := int((180 + float64(long)) * 190463)
+	base91Encode(b, v)
+}
+
+func (long Longitude) Uncompressed(b []byte) {
+	var (
+		degrees, minutes, hundreths, east = long.DMH()
+		v                                 = fmt.Sprintf("%03d%02d.%02d", degrees, minutes, hundreths)
+	)
+	if east {
+		v += "E"
+	} else {
+		v += "W"
+	}
+	copy(b, []byte(b))
+}