// Command nostermd is a minimal NIP-29 managed-group relay built on khatru,
// plus the Nosterm capability handshake (a `features` array in its NIP-11 doc).
//
// It is intentionally small: it enforces group membership for chat writes,
// auto-creates open channels on first join, and advertises itself as a
// "nostermd" so a Nosterm client can feature-gate its UI. The relay is
// assembled from focused internal packages (group, federation, retention,
// relayinfo); this file is the composition root that wires them to env config
// and the network.
package main

import (
	"log"
	"net/http"
	"os"
	"path/filepath"
	"time"

	"fiatjaf.com/nostr/eventstore/boltdb"

	"github.com/nosterm/relay/internal/federation"
	"github.com/nosterm/relay/internal/retention"
)

// defaultMOTD is the built-in message-of-the-day: a "nerdworks.io" ascii banner
// (figlet, standard font) the client shows when RELAY_MOTD is unset.
const defaultMOTD = "                    _                    _          _\n" +
	" _ __   ___ _ __ __| |_      _____  _ __| | _____  (_) ___\n" +
	"| '_ \\ / _ \\ '__/ _` \\ \\ /\\ / / _ \\| '__| |/ / __| | |/ _ \\\n" +
	"| | | |  __/ | | (_| |\\ V  V / (_) | |  |   <\\__ \\_| | (_) |\n" +
	"|_| |_|\\___|_|  \\__,_| \\_/\\_/ \\___/|_|  |_|\\_\\___(_)_|\\___/\n"

func main() {
	addr := envOr("RELAY_ADDR", ":3334")
	dataDir := envOr("RELAY_DATA_DIR", "./data")

	// Embedded, pure-Go storage (no cgo → clean static Docker builds).
	if err := os.MkdirAll(dataDir, 0o755); err != nil {
		log.Fatalf("cannot create data dir: %v", err)
	}

	// Relay identity: signs the 39000-series group metadata/roster events. A
	// stable key is required so those signatures survive restarts (see below).
	sk := loadOrGenerateKey(dataDir)

	store := &boltdb.BoltBackend{Path: filepath.Join(dataDir, "events.bolt")}
	if err := store.Init(); err != nil {
		log.Fatalf("cannot open eventstore: %v", err)
	}

	// Parse optional federation config up front so warnings surface at boot.
	fedCfg, fedWarnings := federation.ParseConfig(os.Getenv("RELAY_FEDERATION_PEERS"))
	for _, w := range fedWarnings {
		log.Printf("federation config: %s", w)
	}

	app := buildRelay(relayConfig{
		secretKey:   sk,
		store:       store,
		name:        envOr("RELAY_NAME", "Nosterm Home Relay"),
		description: envOr("RELAY_DESCRIPTION", "A Nosterm NIP-29 managed-group relay."),
		// NIP-11 contact: a NIP-05-style identifier / address for the relay operator.
		contact: envOr("RELAY_CONTACT", "relay@nosterm.com"),
		// Optional message-of-the-day shown in the client's relay server window;
		// defaults to the nerdworks.io banner when unset.
		motd:   envOr("RELAY_MOTD", defaultMOTD),
		fedCfg: fedCfg,
	})

	// Reconstruct membership/metadata from persisted events so groups survive
	// restarts (without this, every restart silently drops all group state).
	if replayed := app.groups.Rebuild(store); replayed > 0 {
		log.Printf("replayed %d group management event(s) from storage", replayed)
	}

	// Retention: prune old chat messages so the store doesn't grow forever.
	stopRetention := retention.Start(store, retention.Config{
		MaxAge:      time.Duration(envIntOr("RELAY_RETENTION_DAYS", 0)) * 24 * time.Hour,
		MaxMessages: envIntOr("RELAY_RETENTION_MAX_MESSAGES", 0),
		Interval:    time.Duration(envIntOr("RELAY_RETENTION_INTERVAL_MINUTES", 60)) * time.Minute,
	})
	defer stopRetention()

	// Start federation last, once the relay pipeline is fully wired.
	if app.federator != nil {
		app.federator.Start()
		defer app.federator.Stop()
	}

	log.Printf("nostermd pubkey: %s", app.pubKey.Hex())
	log.Printf("listening on %s (%s; %s)", addr, app.groups.Summary(), fedCfg.Summary())
	if err := http.ListenAndServe(addr, app.handler); err != nil {
		log.Fatal(err)
	}
}