Allow multiple call notification responses and improve error handling

infinitime.go

@@ -42,13 +42,19 @@ type Device struct {
 	heartRateChar   *gatt.GattCharacteristic1
 	fsVersionChar   *gatt.GattCharacteristic1
 	fsTransferChar  *gatt.GattCharacteristic1
+	notifEventCh    chan uint8
+	notifEventDone  bool
 	onReconnect     func()
 	Music           MusicCtrl
 	DFU             DFU
 }
 
-var ErrNoDevices = errors.New("no InfiniTime devices found")
-var ErrNotFound = errors.New("could not find any advertising InfiniTime devices")
+var (
+	ErrNoDevices    = errors.New("no InfiniTime devices found")
+	ErrNotFound     = errors.New("could not find any advertising InfiniTime devices")
+	ErrNotConnected = errors.New("not connected")
+	ErrCharNotAvail = errors.New("required characteristic is not available")
+)
 
 type Options struct {
 	AttemptReconnect bool
@@ -332,8 +338,8 @@ func (i *Device) Address() string {
 
 // Version returns InfiniTime's reported firmware version string
 func (i *Device) Version() (string, error) {
-	if !i.device.Properties.Connected {
-		return "", nil
+	if err := i.checkStatus(i.fwVersionChar); err != nil {
+		return "", err
 	}
 	ver, err := i.fwVersionChar.ReadValue(nil)
 	return string(ver), err
@@ -341,8 +347,8 @@ func (i *Device) Version() (string, error) {
 
 // BatteryLevel gets the watch's battery level via the Battery Service
 func (i *Device) BatteryLevel() (uint8, error) {
-	if !i.device.Properties.Connected {
-		return 0, nil
+	if err := i.checkStatus(i.battLevelChar); err != nil {
+		return 0, err
 	}
 	battLevel, err := i.battLevelChar.ReadValue(nil)
 	if err != nil {
@@ -352,8 +358,8 @@ func (i *Device) BatteryLevel() (uint8, error) {
 }
 
 func (i *Device) StepCount() (uint32, error) {
-	if !i.device.Properties.Connected {
-		return 0, nil
+	if err := i.checkStatus(i.stepCountChar); err != nil {
+		return 0, err
 	}
 	stepCountData, err := i.stepCountChar.ReadValue(nil)
 	if err != nil {
@@ -370,8 +376,8 @@ type MotionValues struct {
 
 func (i *Device) Motion() (MotionValues, error) {
 	out := MotionValues{}
-	if !i.device.Properties.Connected {
-		return out, nil
+	if err := i.checkStatus(i.motionValChar); err != nil {
+		return out, err
 	}
 	motionVals, err := i.motionValChar.ReadValue(nil)
 	if err != nil {
@@ -386,8 +392,8 @@ func (i *Device) Motion() (MotionValues, error) {
 }
 
 func (i *Device) HeartRate() (uint8, error) {
-	if !i.device.Properties.Connected {
-		return 0, nil
+	if err := i.checkStatus(i.heartRateChar); err != nil {
+		return 0, err
 	}
 	heartRate, err := i.heartRateChar.ReadValue(nil)
 	if err != nil {
@@ -397,8 +403,8 @@ func (i *Device) HeartRate() (uint8, error) {
 }
 
 func (i *Device) WatchHeartRate() (<-chan uint8, func(), error) {
-	if !i.device.Properties.Connected {
-		return make(<-chan uint8), nil, nil
+	if err := i.checkStatus(i.heartRateChar); err != nil {
+		return nil, nil, err
 	}
 	// Start notifications on heart rate characteristic
 	err := i.heartRateChar.StartNotify()
@@ -439,8 +445,8 @@ func (i *Device) WatchHeartRate() (<-chan uint8, func(), error) {
 }
 
 func (i *Device) WatchBatteryLevel() (<-chan uint8, func(), error) {
-	if !i.device.Properties.Connected {
-		return make(<-chan uint8), nil, nil
+	if err := i.checkStatus(i.battLevelChar); err != nil {
+		return nil, nil, err
 	}
 	// Start notifications on heart rate characteristic
 	err := i.battLevelChar.StartNotify()
@@ -481,8 +487,8 @@ func (i *Device) WatchBatteryLevel() (<-chan uint8, func(), error) {
 }
 
 func (i *Device) WatchStepCount() (<-chan uint32, func(), error) {
-	if !i.device.Properties.Connected {
-		return make(<-chan uint32), nil, nil
+	if err := i.checkStatus(i.stepCountChar); err != nil {
+		return nil, nil, err
 	}
 	// Start notifications on step count characteristic
 	err := i.stepCountChar.StartNotify()
@@ -523,8 +529,8 @@ func (i *Device) WatchStepCount() (<-chan uint32, func(), error) {
 }
 
 func (i *Device) WatchMotion() (<-chan MotionValues, func(), error) {
-	if !i.device.Properties.Connected {
-		return make(<-chan MotionValues), nil, nil
+	if err := i.checkStatus(i.motionValChar); err != nil {
+		return nil, nil, err
 	}
 	// Start notifications on motion characteristic
 	err := i.motionValChar.StartNotify()
@@ -576,8 +582,8 @@ func cancelFunc() (func(), chan struct{}) {
 
 // SetTime sets the watch's time using the Current Time Service
 func (i *Device) SetTime(t time.Time) error {
-	if !i.device.Properties.Connected {
-		return nil
+	if err := i.checkStatus(i.currentTimeChar); err != nil {
+		return err
 	}
 	buf := &bytes.Buffer{}
 	binary.Write(buf, binary.LittleEndian, uint16(t.Year()))
@@ -595,8 +601,8 @@ func (i *Device) SetTime(t time.Time) error {
 // Notify sends a notification to InfiniTime via
 // the Alert Notification Service (ANS)
 func (i *Device) Notify(title, body string) error {
-	if !i.device.Properties.Connected {
-		return nil
+	if err := i.checkStatus(i.newAlertChar); err != nil {
+		return err
 	}
 	return i.newAlertChar.WriteValue(
 		append([]byte{0x00, 0x01, 0x00}, []byte(title+"\x00"+body)...),
@@ -612,11 +618,10 @@ const (
 )
 
 // NotifyCall sends a call notification to the PineTime and returns a channel.
-// This channel will contain the user's response to the call notification. It
-// can only contain one value.
+// This channel will contain the user's response to the call notification.
 func (i *Device) NotifyCall(from string) (<-chan uint8, error) {
-	if !i.device.Properties.Connected {
-		return make(<-chan uint8), nil
+	if err := i.checkStatus(i.newAlertChar); err != nil {
+		return nil, err
 	}
 	// Write call notification to new alert characteristic
 	err := i.newAlertChar.WriteValue(
@@ -626,33 +631,59 @@ func (i *Device) NotifyCall(from string) (<-chan uint8, error) {
 	if err != nil {
 		return nil, err
 	}
+
+	if !i.notifEventDone {
+		err = i.initNotifEvent()
+		if err != nil {
+			return nil, err
+		}
+		i.notifEventDone = true
+	}
+
+	return i.notifEventCh, nil
+}
+
+// initNotifEvent initializes the notification event channel
+func (i *Device) initNotifEvent() error {
 	// Start notifications on notification event characteristic
-	err = i.notifEventChar.StartNotify()
+	err := i.notifEventChar.StartNotify()
 	if err != nil {
-		return nil, err
+		return err
 	}
 	// Watch properties of notification event characteristic
 	ch, err := i.notifEventChar.WatchProperties()
 	if err != nil {
-		return nil, err
+		return err
 	}
 	// Create new output channel for status
-	out := make(chan uint8, 1)
+	i.notifEventCh = make(chan uint8, 1)
 	go func() {
 		// For every event
 		for event := range ch {
 			// If value changed
 			if event.Name == "Value" {
 				// Send status to channel
-				out <- uint8(event.Value.([]byte)[0])
-				return
+				i.notifEventCh <- uint8(event.Value.([]byte)[0])
 			}
 		}
 	}()
-	return out, nil
+	return nil
 }
 
 // FS creates and returns a new filesystem from the device
 func (i *Device) FS() (*blefs.FS, error) {
+	if err := i.checkStatus(i.currentTimeChar); err != nil {
+		return nil, err
+	}
 	return blefs.New(i.fsTransferChar)
 }
+
+func (i *Device) checkStatus(char *gatt.GattCharacteristic1) error {
+	if !i.device.Properties.Connected {
+		return ErrNotConnected
+	}
+	if char == nil {
+		return ErrCharNotAvail
+	}
+	return nil
+}