feat(cmd): main entrypoint and config loader

cmd/ezcoo-usb-control/config.example.yaml

@@ -0,0 +1,12 @@
+device:
+  port: /dev/ttyUSB0
+  baud: 57600
+  poll_interval: 15s
+
+mqtt:
+  broker: tcp://192.168.1.10:1883
+  username: ""
+  password: ""
+  client_id: ezcoo-usb-control
+  base_topic: ezcoo
+  discovery_prefix: homeassistant

cmd/ezcoo-usb-control/config.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"gopkg.in/yaml.v3"
+
+	"gitea.berezovskyi.dev/oleksandr/ezcoo-usb-control/pkg/bridge"
+	"gitea.berezovskyi.dev/oleksandr/ezcoo-usb-control/pkg/ezcoo"
+)
+
+type appConfig struct {
+	Device ezcoo.Config  `yaml:"device"`
+	MQTT   bridge.Config `yaml:"mqtt"`
+}
+
+func (c *appConfig) SetDefaults() {
+	c.Device.SetDefaults()
+	c.MQTT.SetDefaults()
+}
+
+func (c *appConfig) Validate() error {
+	if err := c.Device.Validate(); err != nil {
+		return err
+	}
+	return c.MQTT.Validate()
+}
+
+func loadConfig(path string) (appConfig, error) {
+	var cfg appConfig
+	if path != "" {
+		f, err := os.Open(path)
+		if err != nil {
+			return cfg, fmt.Errorf("open config: %w", err)
+		}
+		defer f.Close()
+		if err := yaml.NewDecoder(f).Decode(&cfg); err != nil {
+			return cfg, fmt.Errorf("parse config: %w", err)
+		}
+	}
+	cfg.SetDefaults()
+	if err := cfg.Validate(); err != nil {
+		return cfg, fmt.Errorf("validate config: %w", err)
+	}
+	return cfg, nil
+}

cmd/ezcoo-usb-control/main.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"log/slog"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"gitea.berezovskyi.dev/oleksandr/ezcoo-usb-control/pkg/bridge"
+	"gitea.berezovskyi.dev/oleksandr/ezcoo-usb-control/pkg/ezcoo"
+)
+
+func main() {
+	cfgPath := flag.String("config", "", "path to config YAML (optional)")
+	debug := flag.Bool("debug", false, "enable debug logging")
+	flag.Parse()
+
+	level := slog.LevelInfo
+	if *debug {
+		level = slog.LevelDebug
+	}
+	slog.SetDefault(slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{Level: level})))
+
+	cfg, err := loadConfig(*cfgPath)
+	if err != nil {
+		slog.Error("load config", "err", err)
+		os.Exit(1)
+	}
+
+	ctx, cancel := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer cancel()
+	done := ctx.Done()
+
+	dev := ezcoo.NewDevice(cfg.Device)
+	b := bridge.New(cfg.MQTT, dev, done)
+
+	go dev.Run(b.OnState, b.SetAvailable, done)
+
+	if err := b.Connect(); err != nil {
+		if errors.Is(err, bridge.ErrShutdown) {
+			return
+		}
+		slog.Error("MQTT connect", "err", err)
+		os.Exit(1)
+	}
+	b.Run()
+}