package main

import (
	"context"
	"errors"
	"flag"
	"fmt"
	"os"
	"time"
)

const defaultConfigPath = "/etc/oci-l4-relay/config.json"

func main() {
	if len(os.Args) < 2 {
		fatal(errors.New("expected bootstrap, reconcile, admission, smtp-deny, logs, status, health, or telemetry"))
	}
	flags := flag.NewFlagSet(os.Args[1], flag.ExitOnError)
	configPath := flags.String("config", defaultConfigPath, "configuration path")
	_ = flags.Parse(os.Args[2:])
	configuration, err := loadConfig(*configPath)
	if err != nil {
		fatal(err)
	}
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Minute)
	defer cancel()
	switch os.Args[1] {
	case "bootstrap":
		err = bootstrap(ctx, configuration)
	case "reconcile":
		err = reconcile(ctx, configuration)
	case "admission":
		if flags.NArg() != 1 {
			fatal(errors.New("admission expects refresh or restore"))
		}
		err = runAdmissionOperation(ctx, configuration, flags.Arg(0))
	case "smtp-deny":
		if flags.NArg() != 1 {
			fatal(errors.New("smtp-deny expects refresh or restore"))
		}
		err = runSMTPDenyOperation(ctx, configuration, flags.Arg(0))
	case "logs":
		if flags.NArg() != 1 || flags.Arg(0) != "update" {
			fatal(errors.New("logs expects update"))
		}
		err = updateLogCredential(ctx, configuration)
	case "status":
		err = reportStatus(configuration, false)
	case "health":
		err = reportStatus(configuration, true)
	case "telemetry":
		err = reportTelemetry(ctx, configuration)
	default:
		err = fmt.Errorf("unknown command %q", os.Args[1])
	}
	if err != nil {
		fatal(err)
	}
}

func runSMTPDenyOperation(ctx context.Context, configuration config, operation string) error {
	if configuration.MailRelayAddress == "" {
		return nil
	}
	switch operation {
	case "refresh":
		return updateSMTPDeny(ctx, configuration)
	case "restore":
		return restoreSMTPDeny(ctx, configuration)
	default:
		return fmt.Errorf("unknown SMTP deny operation %q", operation)
	}
}

func runAdmissionOperation(ctx context.Context, configuration config, operation string) error {
	switch operation {
	case "refresh":
		return updateAdmission(ctx, configuration)
	case "restore":
		return restoreAdmission(ctx, configuration)
	default:
		return fmt.Errorf("unknown admission operation %q", operation)
	}
}

func fatal(err error) {
	fmt.Fprintln(os.Stderr, err)
	os.Exit(1)
}