// main is the composition root for the application.
// It wires together config, logger, and domain services — nothing more.
// Business logic lives in internal/; cmd/ is deliberately thin.
package main

import (
	"fmt"
	"os"
	"path/filepath"

	"gitea.djmil.dev/go/template/internal/config"
	"gitea.djmil.dev/go/template/internal/greeter"
	"gitea.djmil.dev/go/template/internal/logger"
	"gitea.djmil.dev/go/template/pkg/result"
)

func main() {
	if err := run(); err != nil {
		fmt.Fprintf(os.Stderr, "fatal: %v\n", err)
		if stack := result.StackTrace(err); stack != "" {
			fmt.Fprintf(os.Stderr, "%s\n", stack)
		}
		os.Exit(1)
	}
}

func run() (err error) {
	defer result.Catch(&err)

	// ── Config ────────────────────────────────────────────────────────────────
	cfg := config.Load()

	// ── Logger ────────────────────────────────────────────────────────────────
	var log *logger.Logger
	if cfg.App.Env == "dev" {
		log = logger.NewDevelopment()
	} else {
		log = result.Of(logger.New(cfg.Logger.Level)).Expect("create logger")
	}

	log.WithFields(map[string]any{
		"app": filepath.Base(os.Args[0]),
		"env": cfg.App.Env,
	}).Info("starting up")

	// ── Services ──────────────────────────────────────────────────────────────
	var greetSvc greeter.Greeter = greeter.New(log)

	// ── Example usage ─────────────────────────────────────────────────────────
	msg := greetSvc.Greet(cfg.Greeter.Name).Expect("greeting")

	log.WithField("message", msg).Info("greeting complete")

	fmt.Printf("%s (listening on :%d)\n", msg, cfg.App.Port)

	return nil
}