package main

import (
	"context"
	"log/slog"
	"os"
	"os/signal"
	"syscall"
	"time"
)

func main() {
	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
	slog.SetDefault(logger)

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	// Handle OS signals
	go func() {
		sigChan := make(chan os.Signal, 1)
		signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
		<-sigChan
		slog.Info("Received shutdown signal")
		cancel()
	}()

	if err := run(ctx); err != nil {
		slog.Error("Application error", "error", err)
		os.Exit(1)
	}
}

func run(ctx context.Context) error {
	slog.Info("Starting application...")

	// Simulate long running process or server start
	// e.g. server.ListenAndServe()

	<-ctx.Done()
	slog.Info("Shutting down application...")
	
	// Cleanup with timeout
	_, shutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer shutdownCancel()

	// Pretend to cleanup
	time.Sleep(100 * time.Millisecond)
	
	return nil
}