fm-rds-tx/cmd/fmrtx/main.go

package main

import (
	"flag"
	"fmt"
	"log"
	"net/http"
	"os"
	"time"

	apppkg "github.com/jan/fm-rds-tx/internal/app"
	cfgpkg "github.com/jan/fm-rds-tx/internal/config"
	ctrlpkg "github.com/jan/fm-rds-tx/internal/control"
	drypkg "github.com/jan/fm-rds-tx/internal/dryrun"
)

func main() {
	configPath := flag.String("config", "", "path to JSON config")
	printConfig := flag.Bool("print-config", false, "print effective config and exit")
	dryRun := flag.Bool("dry-run", false, "run no-hardware dry-run output")
	dryOutput := flag.String("dry-output", "-", "dry-run output path or - for stdout")
	simulate := flag.Bool("simulate-tx", false, "run simulated Soapy/backend transmit path")
	simulateOutput := flag.String("simulate-output", "", "simulated transmit output file")
	simulateDuration := flag.Duration("simulate-duration", 500*time.Millisecond, "simulated transmit duration")
	flag.Parse()

	cfg, err := cfgpkg.Load(*configPath)
	if err != nil {
		log.Fatalf("load config: %v", err)
	}

	if *printConfig {
		preemph := "off"
		if cfg.FM.PreEmphasisUS > 0 {
			preemph = fmt.Sprintf("%.0fµs", cfg.FM.PreEmphasisUS)
		}
		fmt.Printf("backend=%s freq=%.1fMHz stereo=%t rds=%t preemph=%s limiter=%t fmmod=%t deviation=±%.0fHz listen=%s\n",
			cfg.Backend.Kind, cfg.FM.FrequencyMHz, cfg.FM.StereoEnabled, cfg.RDS.Enabled,
			preemph, cfg.FM.LimiterEnabled, cfg.FM.FMModulationEnabled, cfg.FM.MaxDeviationHz,
			cfg.Control.ListenAddress)
		return
	}

	if *dryRun {
		frame := drypkg.Generate(cfg)
		if err := drypkg.WriteJSON(*dryOutput, frame); err != nil {
			log.Fatalf("dry-run failed: %v", err)
		}
		if *dryOutput != "" && *dryOutput != "-" {
			fmt.Fprintf(os.Stderr, "dry run frame written to %s\n", *dryOutput)
		}
		return
	}

	if *simulate {
		summary, err := apppkg.RunSimulatedTransmit(cfg, *simulateOutput, *simulateDuration)
		if err != nil {
			log.Fatalf("simulate-tx failed: %v", err)
		}
		fmt.Println(summary)
		return
	}

	srv := ctrlpkg.NewServer(cfg)
	log.Printf("fm-rds-tx listening on %s", cfg.Control.ListenAddress)
	log.Fatal(http.ListenAndServe(cfg.Control.ListenAddress, srv.Handler()))
}