Re-add watch commands to itctl

cmd/itctl/main.go

@@ -2,6 +2,8 @@ package main
 
 import (
 	"os"
+	"os/signal"
+	"syscall"
 
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
@@ -174,6 +176,49 @@ func main() {
 					},
 				},
 			},
+			{
+				Name:  "watch",
+				Usage: "Watch a value for changes",
+				Subcommands: []*cli.Command{
+					{
+						Flags: []cli.Flag{
+							&cli.BoolFlag{Name: "json"},
+							&cli.BoolFlag{Name: "shell"},
+						},
+						Name:   "heart",
+						Usage:  "Watch heart rate value for changes",
+						Action: watchHeart,
+					},
+					{
+						Flags: []cli.Flag{
+							&cli.BoolFlag{Name: "json"},
+							&cli.BoolFlag{Name: "shell"},
+						},
+						Name:   "steps",
+						Usage:  "Watch step count value for changes",
+						Action: watchStepCount,
+					},
+					{
+						Flags: []cli.Flag{
+							&cli.BoolFlag{Name: "json"},
+							&cli.BoolFlag{Name: "shell"},
+						},
+						Name:   "motion",
+						Usage:  "Watch motion coordinates for changes",
+						Action: watchMotion,
+					},
+					{
+						Flags: []cli.Flag{
+							&cli.BoolFlag{Name: "json"},
+							&cli.BoolFlag{Name: "shell"},
+						},
+						Name:    "battery",
+						Aliases: []string{"batt"},
+						Usage:   "Watch battery level value for changes",
+						Action:  watchBattLevel,
+					},
+				},
+			},
 		},
 		Before: func(c *cli.Context) error {
 			newClient, err := api.New(c.String("socket-path"))
@@ -196,3 +241,17 @@ func main() {
 		log.Fatal().Err(err).Msg("Error while running app")
 	}
 }
+
+func catchSignal(fn func()) {
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(
+		sigCh,
+		syscall.SIGINT,
+		syscall.SIGTERM,
+	)
+	go func() {
+		<-sigCh
+		fn()
+		os.Exit(0)
+	}()
+}

cmd/itctl/watch.go

@@ -0,0 +1,104 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+
+	"github.com/urfave/cli/v2"
+)
+
+func watchHeart(c *cli.Context) error {
+	heartCh, cancel, err := client.WatchHeartRate()
+	if err != nil {
+		return err
+	}
+
+	catchSignal(cancel)
+
+	for heartRate := range heartCh {
+		if c.Bool("json") {
+			json.NewEncoder(os.Stdout).Encode(
+				map[string]uint8{"heartRate": heartRate},
+			)
+		} else if c.Bool("shell") {
+			fmt.Printf("HEART_RATE=%d\n", heartRate)
+		} else {
+			fmt.Println(heartRate, "BPM")
+		}
+	}
+
+	return nil
+}
+
+func watchBattLevel(c *cli.Context) error {
+	battLevelCh, cancel, err := client.WatchBatteryLevel()
+	if err != nil {
+		return err
+	}
+
+	catchSignal(cancel)
+
+	for battLevel := range battLevelCh {
+		if c.Bool("json") {
+			json.NewEncoder(os.Stdout).Encode(
+				map[string]uint8{"battLevel": battLevel},
+			)
+		} else if c.Bool("shell") {
+			fmt.Printf("BATTERY_LEVEL=%d\n", battLevel)
+		} else {
+			fmt.Printf("%d%%\n", battLevel)
+		}
+	}
+
+	return nil
+}
+
+func watchStepCount(c *cli.Context) error {
+	stepCountCh, cancel, err := client.WatchStepCount()
+	if err != nil {
+		return err
+	}
+
+	catchSignal(cancel)
+
+	for stepCount := range stepCountCh {
+		if c.Bool("json") {
+			json.NewEncoder(os.Stdout).Encode(
+				map[string]uint32{"stepCount": stepCount},
+			)
+		} else if c.Bool("shell") {
+			fmt.Printf("STEP_COUNT=%d\n", stepCount)
+		} else {
+			fmt.Println(stepCount, "Steps")
+		}
+	}
+
+	return nil
+}
+
+func watchMotion(c *cli.Context) error {
+	motionCh, cancel, err := client.WatchMotion()
+	if err != nil {
+		return err
+	}
+
+	catchSignal(cancel)
+
+	for motionVals := range motionCh {
+		if c.Bool("json") {
+			json.NewEncoder(os.Stdout).Encode(motionVals)
+		} else if c.Bool("shell") {
+			fmt.Printf(
+				"X=%d\nY=%d\nZ=%d\n",
+				motionVals.X,
+				motionVals.Y,
+				motionVals.Z,
+			)
+		} else {
+			fmt.Println(motionVals)
+		}
+	}
+
+	return nil
+}