add some automation to pi side

pi/roverd/auto_charge.go

@@ -0,0 +1,109 @@
+package roverd
+
+import (
+	"context"
+	"log"
+	"time"
+)
+
+const (
+	autoChargeTimeout  = 10 * time.Second
+	autoChargeCooldown = 2 * time.Minute
+	sourceHomeBase     = 1 << 1
+)
+
+type AutoChargeController struct {
+	adapter       *SerialAdapter
+	events        chan<- RoverEvent
+	logger        *log.Logger
+	timerStart    time.Time
+	cooldownUntil time.Time
+	lastState     byte
+	lastSources   byte
+}
+
+func NewAutoChargeController(adapter *SerialAdapter, events chan<- RoverEvent, logger *log.Logger) *AutoChargeController {
+	return &AutoChargeController{
+		adapter: adapter,
+		events:  events,
+		logger:  logger,
+	}
+}
+
+func (a *AutoChargeController) Run(ctx context.Context, samples <-chan SensorSample) {
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case sample := <-samples:
+			a.processSample(sample)
+		}
+	}
+}
+
+func (a *AutoChargeController) processSample(sample SensorSample) {
+	now := time.Now()
+	docked := sample.ChargeSources&sourceHomeBase != 0
+	charging := isCharging(sample.ChargingState)
+
+	if !docked || charging {
+		if !a.timerStart.IsZero() {
+			a.emitEvent("autoCharge.timerCleared", map[string]any{
+				"durationMs": time.Since(a.timerStart).Milliseconds(),
+			})
+		}
+		a.timerStart = time.Time{}
+		a.lastState = sample.ChargingState
+		a.lastSources = sample.ChargeSources
+		return
+	}
+
+	// docked but not charging
+	if a.cooldownUntil.After(now) {
+		return
+	}
+
+	if a.timerStart.IsZero() {
+		a.timerStart = now
+		a.emitEvent("autoCharge.timerStarted", map[string]any{
+			"chargingState": sample.ChargingState,
+		})
+		return
+	}
+
+	if now.Sub(a.timerStart) >= autoChargeTimeout {
+		if err := a.adapter.SeekDock(); err != nil {
+			a.emitEvent("autoCharge.seekDockError", map[string]any{"error": err.Error()})
+		} else {
+			a.emitEvent("autoCharge.seekDockIssued", map[string]any{
+				"waitingMs": autoChargeTimeout.Milliseconds(),
+			})
+		}
+		a.timerStart = time.Time{}
+		a.cooldownUntil = now.Add(autoChargeCooldown)
+	}
+}
+
+func isCharging(state byte) bool {
+	switch state {
+	case 1, 2, 3, 4:
+		return true
+	default:
+		return false
+	}
+}
+
+func (a *AutoChargeController) emitEvent(event string, data map[string]any) {
+	if a.events == nil {
+		return
+	}
+	select {
+	case a.events <- RoverEvent{
+		Type:   "event",
+		Event:  event,
+		Ts:     time.Now().UnixMilli(),
+		Data:   data,
+	}:
+	default:
+	}
+}