package node

import (
	"context"
	"crypto/tls"
	"crypto/x509"
	"encoding/pem"
	"fmt"
	mathrand "math/rand"
	"net"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/libp2p/go-libp2p"
	libp2ppubsub "github.com/libp2p/go-libp2p-pubsub"
	"github.com/libp2p/go-libp2p/core/crypto"
	"github.com/libp2p/go-libp2p/core/host"
	"github.com/libp2p/go-libp2p/core/peer"

	noise "github.com/libp2p/go-libp2p/p2p/security/noise"
	"github.com/multiformats/go-multiaddr"
	"go.uber.org/zap"
	"golang.org/x/crypto/acme"
	"golang.org/x/crypto/acme/autocert"

	"github.com/DeBrosOfficial/network/pkg/config"
	"github.com/DeBrosOfficial/network/pkg/discovery"
	"github.com/DeBrosOfficial/network/pkg/encryption"
	"github.com/DeBrosOfficial/network/pkg/gateway"
	"github.com/DeBrosOfficial/network/pkg/ipfs"
	"github.com/DeBrosOfficial/network/pkg/logging"
	"github.com/DeBrosOfficial/network/pkg/pubsub"
	database "github.com/DeBrosOfficial/network/pkg/rqlite"
)

// Node represents a network node with RQLite database
type Node struct {
	config *config.Config
	logger *logging.ColoredLogger
	host   host.Host

	rqliteManager    *database.RQLiteManager
	rqliteAdapter    *database.RQLiteAdapter
	clusterDiscovery *database.ClusterDiscoveryService

	// Peer discovery
	peerDiscoveryCancel context.CancelFunc

	// PubSub
	pubsub *pubsub.ClientAdapter

	// Discovery
	discoveryManager *discovery.Manager

	// IPFS Cluster config manager
	clusterConfigManager *ipfs.ClusterConfigManager

	// Full gateway (for API, auth, pubsub, and internal service routing)
	apiGateway *gateway.Gateway
	apiGatewayServer *http.Server

	// SNI gateway (for TCP routing of raft, ipfs, olric, etc.)
	sniGateway *gateway.TCPSNIGateway

	// Shared certificate manager for HTTPS and SNI
	certManager *autocert.Manager
}

// NewNode creates a new network node
func NewNode(cfg *config.Config) (*Node, error) {
	// Create colored logger
	logger, err := logging.NewColoredLogger(logging.ComponentNode, true)
	if err != nil {
		return nil, fmt.Errorf("failed to create logger: %w", err)
	}

	return &Node{
		config: cfg,
		logger: logger,
	}, nil
}

// startRQLite initializes and starts the RQLite database
func (n *Node) startRQLite(ctx context.Context) error {
	n.logger.Info("Starting RQLite database")

	// Determine node identifier for log filename - use node ID for unique filenames
	nodeID := n.config.Node.ID
	if nodeID == "" {
		// Default to "node" if ID is not set
		nodeID = "node"
	}

	// Create RQLite manager
	n.rqliteManager = database.NewRQLiteManager(&n.config.Database, &n.config.Discovery, n.config.Node.DataDir, n.logger.Logger)
	n.rqliteManager.SetNodeType(nodeID)

	// Initialize cluster discovery service if LibP2P host is available
	if n.host != nil && n.discoveryManager != nil {
		// Create cluster discovery service (all nodes are unified)
		n.clusterDiscovery = database.NewClusterDiscoveryService(
			n.host,
			n.discoveryManager,
			n.rqliteManager,
			n.config.Node.ID,
			"node", // Unified node type
			n.config.Discovery.RaftAdvAddress,
			n.config.Discovery.HttpAdvAddress,
			n.config.Node.DataDir,
			n.logger.Logger,
		)

		// Set discovery service on RQLite manager BEFORE starting RQLite
		// This is critical for pre-start cluster discovery during recovery
		n.rqliteManager.SetDiscoveryService(n.clusterDiscovery)

		// Start cluster discovery (but don't trigger initial sync yet)
		if err := n.clusterDiscovery.Start(ctx); err != nil {
			return fmt.Errorf("failed to start cluster discovery: %w", err)
		}

		// Publish initial metadata (with log_index=0) so peers can discover us during recovery
		// The metadata will be updated with actual log index after RQLite starts
		n.clusterDiscovery.UpdateOwnMetadata()

		n.logger.Info("Cluster discovery service started (waiting for RQLite)")
	}

	// Start RQLite FIRST before updating metadata
	if err := n.rqliteManager.Start(ctx); err != nil {
		return err
	}

	// NOW update metadata after RQLite is running
	if n.clusterDiscovery != nil {
		n.clusterDiscovery.UpdateOwnMetadata()
		n.clusterDiscovery.TriggerSync() // Do initial cluster sync now that RQLite is ready
		n.logger.Info("RQLite metadata published and cluster synced")
	}

	// Create adapter for sql.DB compatibility
	adapter, err := database.NewRQLiteAdapter(n.rqliteManager)
	if err != nil {
		return fmt.Errorf("failed to create RQLite adapter: %w", err)
	}
	n.rqliteAdapter = adapter

	return nil
}

// extractIPFromMultiaddr extracts the IP address from a peer multiaddr
// Supports IP4, IP6, DNS4, DNS6, and DNSADDR protocols
func extractIPFromMultiaddr(multiaddrStr string) string {
	ma, err := multiaddr.NewMultiaddr(multiaddrStr)
	if err != nil {
		return ""
	}

	// First, try to extract direct IP address
	var ip string
	var dnsName string
	multiaddr.ForEach(ma, func(c multiaddr.Component) bool {
		switch c.Protocol().Code {
		case multiaddr.P_IP4, multiaddr.P_IP6:
			ip = c.Value()
			return false // Stop iteration - found IP
		case multiaddr.P_DNS4, multiaddr.P_DNS6, multiaddr.P_DNSADDR:
			dnsName = c.Value()
			// Continue to check for IP, but remember DNS name as fallback
		}
		return true
	})

	// If we found a direct IP, return it
	if ip != "" {
		return ip
	}

	// If we found a DNS name, try to resolve it
	if dnsName != "" {
		if resolvedIPs, err := net.LookupIP(dnsName); err == nil && len(resolvedIPs) > 0 {
			// Prefer IPv4 addresses, but accept IPv6 if that's all we have
			for _, resolvedIP := range resolvedIPs {
				if resolvedIP.To4() != nil {
					return resolvedIP.String()
				}
			}
			// Return first IPv6 address if no IPv4 found
			return resolvedIPs[0].String()
		}
	}

	return ""
}

// peerSource returns a PeerSource that yields peers from configured peers.
func peerSource(peerAddrs []string, logger *zap.Logger) func(context.Context, int) <-chan peer.AddrInfo {
	return func(ctx context.Context, num int) <-chan peer.AddrInfo {
		out := make(chan peer.AddrInfo, num)
		go func() {
			defer close(out)
			count := 0
			for _, s := range peerAddrs {
				if count >= num {
					return
				}
				ma, err := multiaddr.NewMultiaddr(s)
				if err != nil {
					logger.Debug("invalid peer multiaddr", zap.String("addr", s), zap.Error(err))
					continue
				}
				ai, err := peer.AddrInfoFromP2pAddr(ma)
				if err != nil {
					logger.Debug("failed to parse peer address", zap.String("addr", s), zap.Error(err))
					continue
				}
				select {
				case out <- *ai:
					count++
				case <-ctx.Done():
					return
				}
			}
		}()
		return out
	}
}

// hasPeerConnections checks if we're connected to any peers
func (n *Node) hasPeerConnections() bool {
	if n.host == nil || len(n.config.Discovery.BootstrapPeers) == 0 {
		return false
	}

	connectedPeers := n.host.Network().Peers()
	if len(connectedPeers) == 0 {
		return false
	}

	// Parse peer IDs
	peerIDs := make(map[peer.ID]bool)
	for _, peerAddr := range n.config.Discovery.BootstrapPeers {
		ma, err := multiaddr.NewMultiaddr(peerAddr)
		if err != nil {
			continue
		}
		peerInfo, err := peer.AddrInfoFromP2pAddr(ma)
		if err != nil {
			continue
		}
		peerIDs[peerInfo.ID] = true
	}

	// Check if any connected peer is in our peer list
	for _, peerID := range connectedPeers {
		if peerIDs[peerID] {
			return true
		}
	}

	return false
}

// calculateNextBackoff calculates the next backoff interval with exponential growth
func calculateNextBackoff(current time.Duration) time.Duration {
	// Multiply by 1.5 for gentler exponential growth
	next := time.Duration(float64(current) * 1.5)
	// Cap at 10 minutes
	maxInterval := 10 * time.Minute
	if next > maxInterval {
		next = maxInterval
	}
	return next
}

// addJitter adds random jitter to prevent thundering herd
func addJitter(interval time.Duration) time.Duration {
	// Add ±20% jitter
	jitterPercent := 0.2
	jitterRange := float64(interval) * jitterPercent
	jitter := (mathrand.Float64() - 0.5) * 2 * jitterRange // -jitterRange to +jitterRange

	result := time.Duration(float64(interval) + jitter)
	// Ensure we don't go below 1 second
	if result < time.Second {
		result = time.Second
	}
	return result
}

// connectToPeerAddr connects to a single peer address
func (n *Node) connectToPeerAddr(ctx context.Context, addr string) error {
	ma, err := multiaddr.NewMultiaddr(addr)
	if err != nil {
		return fmt.Errorf("invalid multiaddr: %w", err)
	}

	// Extract peer info from multiaddr
	peerInfo, err := peer.AddrInfoFromP2pAddr(ma)
	if err != nil {
		return fmt.Errorf("failed to extract peer info: %w", err)
	}

	// Avoid dialing ourselves: if the address resolves to our own peer ID, skip.
	if n.host != nil && peerInfo.ID == n.host.ID() {
		n.logger.ComponentDebug(logging.ComponentNode, "Skipping peer address because it resolves to self",
			zap.String("addr", addr),
			zap.String("peer_id", peerInfo.ID.String()))
		return nil
	}

	// Log resolved peer info prior to connect
	n.logger.ComponentDebug(logging.ComponentNode, "Resolved peer",
		zap.String("peer_id", peerInfo.ID.String()),
		zap.String("addr", addr),
		zap.Int("addr_count", len(peerInfo.Addrs)),
	)

	// Connect to the peer
	if err := n.host.Connect(ctx, *peerInfo); err != nil {
		return fmt.Errorf("failed to connect to peer: %w", err)
	}

	n.logger.Info("Connected to peer",
		zap.String("peer", peerInfo.ID.String()),
		zap.String("addr", addr))

	return nil
}

// connectToPeers connects to configured LibP2P peers
func (n *Node) connectToPeers(ctx context.Context) error {
	if len(n.config.Discovery.BootstrapPeers) == 0 {
		n.logger.ComponentDebug(logging.ComponentNode, "No peers configured")
		return nil
	}

	// Use passed context with a reasonable timeout for peer connections
	connectCtx, cancel := context.WithTimeout(ctx, 30*time.Second)
	defer cancel()

	for _, peerAddr := range n.config.Discovery.BootstrapPeers {
		if err := n.connectToPeerAddr(connectCtx, peerAddr); err != nil {
			n.logger.ComponentWarn(logging.ComponentNode, "Failed to connect to peer",
				zap.String("addr", peerAddr),
				zap.Error(err))
			continue
		}
	}

	return nil
}

// startLibP2P initializes the LibP2P host
func (n *Node) startLibP2P() error {
	n.logger.ComponentInfo(logging.ComponentLibP2P, "Starting LibP2P host")

	// Load or create persistent identity
	identity, err := n.loadOrCreateIdentity()
	if err != nil {
		return fmt.Errorf("failed to load identity: %w", err)
	}

	// Create LibP2P host with explicit listen addresses
	var opts []libp2p.Option
	opts = append(opts,
		libp2p.Identity(identity),
		libp2p.Security(noise.ID, noise.New),
		libp2p.DefaultMuxers,
	)

	// Add explicit listen addresses from config
	if len(n.config.Node.ListenAddresses) > 0 {
		listenAddrs := make([]multiaddr.Multiaddr, 0, len(n.config.Node.ListenAddresses))
		for _, addr := range n.config.Node.ListenAddresses {
			ma, err := multiaddr.NewMultiaddr(addr)
			if err != nil {
				return fmt.Errorf("invalid listen address %s: %w", addr, err)
			}
			listenAddrs = append(listenAddrs, ma)
		}
		opts = append(opts, libp2p.ListenAddrs(listenAddrs...))
		n.logger.ComponentInfo(logging.ComponentLibP2P, "Configured listen addresses",
			zap.Strings("addrs", n.config.Node.ListenAddresses))
	}

	// For localhost/development, disable NAT services
	// For production, these would be enabled
	isLocalhost := len(n.config.Node.ListenAddresses) > 0 &&
		(strings.Contains(n.config.Node.ListenAddresses[0], "localhost") ||
			strings.Contains(n.config.Node.ListenAddresses[0], "127.0.0.1"))

	if isLocalhost {
		n.logger.ComponentInfo(logging.ComponentLibP2P, "Localhost detected - disabling NAT services for local development")
		// Don't add NAT/AutoRelay options for localhost
	} else {
		n.logger.ComponentInfo(logging.ComponentLibP2P, "Production mode - enabling NAT services")
		opts = append(opts,
			libp2p.EnableNATService(),
			libp2p.EnableAutoNATv2(),
			libp2p.EnableRelay(),
			libp2p.NATPortMap(),
			libp2p.EnableAutoRelayWithPeerSource(
				peerSource(n.config.Discovery.BootstrapPeers, n.logger.Logger),
			),
		)
	}

	h, err := libp2p.New(opts...)
	if err != nil {
		return err
	}

	n.host = h

	// Initialize pubsub
	ps, err := libp2ppubsub.NewGossipSub(context.Background(), h,
		libp2ppubsub.WithPeerExchange(true),
		libp2ppubsub.WithFloodPublish(true), // Ensure messages reach all peers, not just mesh
		libp2ppubsub.WithDirectPeers(nil),   // Enable direct peer connections
	)
	if err != nil {
		return fmt.Errorf("failed to create pubsub: %w", err)
	}

	// Create pubsub adapter with "node" namespace
	n.pubsub = pubsub.NewClientAdapter(ps, n.config.Discovery.NodeNamespace)
	n.logger.Info("Initialized pubsub adapter on namespace", zap.String("namespace", n.config.Discovery.NodeNamespace))

	// Log configured peers
	if len(n.config.Discovery.BootstrapPeers) > 0 {
		n.logger.ComponentInfo(logging.ComponentNode, "Configured peers",
			zap.Strings("peers", n.config.Discovery.BootstrapPeers))
	} else {
		n.logger.ComponentDebug(logging.ComponentNode, "No peers configured")
	}

	// Connect to LibP2P peers if configured
	if err := n.connectToPeers(context.Background()); err != nil {
		n.logger.ComponentWarn(logging.ComponentNode, "Failed to connect to peers", zap.Error(err))
		// Don't fail - continue without peer connections
	}

	// Start exponential backoff reconnection for peers
	if len(n.config.Discovery.BootstrapPeers) > 0 {
		peerCtx, cancel := context.WithCancel(context.Background())
		n.peerDiscoveryCancel = cancel

		go func() {
			interval := 5 * time.Second
			consecutiveFailures := 0

			n.logger.ComponentInfo(logging.ComponentNode, "Starting peer reconnection with exponential backoff",
				zap.Duration("initial_interval", interval),
				zap.Duration("max_interval", 10*time.Minute))

			for {
				select {
				case <-peerCtx.Done():
					n.logger.ComponentDebug(logging.ComponentNode, "Peer reconnection loop stopped")
					return
				default:
				}

				// Check if we need to attempt connection
				if !n.hasPeerConnections() {
					n.logger.ComponentDebug(logging.ComponentNode, "Attempting peer connection",
						zap.Duration("current_interval", interval),
						zap.Int("consecutive_failures", consecutiveFailures))

					if err := n.connectToPeers(context.Background()); err != nil {
						consecutiveFailures++
						// Calculate next backoff interval
						jitteredInterval := addJitter(interval)
						n.logger.ComponentDebug(logging.ComponentNode, "Peer connection failed, backing off",
							zap.Error(err),
							zap.Duration("next_attempt_in", jitteredInterval),
							zap.Int("consecutive_failures", consecutiveFailures))

						// Sleep with jitter
						select {
						case <-peerCtx.Done():
							return
						case <-time.After(jitteredInterval):
						}

						// Increase interval for next attempt
						interval = calculateNextBackoff(interval)

						// Log interval increases occasionally to show progress
						if consecutiveFailures%5 == 0 {
							n.logger.ComponentInfo(logging.ComponentNode, "Peer connection still failing",
								zap.Int("consecutive_failures", consecutiveFailures),
								zap.Duration("current_interval", interval))
						}
					} else {
						// Success! Reset interval and counters
						if consecutiveFailures > 0 {
							n.logger.ComponentInfo(logging.ComponentNode, "Successfully connected to peers",
								zap.Int("failures_overcome", consecutiveFailures))
						}
						interval = 5 * time.Second
						consecutiveFailures = 0

						// Wait 30 seconds before checking connection again
						select {
						case <-peerCtx.Done():
							return
						case <-time.After(30 * time.Second):
						}
					}
				} else {
					// We have peer connections, just wait and check periodically
					select {
					case <-peerCtx.Done():
						return
					case <-time.After(30 * time.Second):
					}
				}
			}
		}()
	}

	// Add peers to peerstore for peer exchange
	if len(n.config.Discovery.BootstrapPeers) > 0 {
		n.logger.ComponentInfo(logging.ComponentNode, "Adding peers to peerstore")
		for _, peerAddr := range n.config.Discovery.BootstrapPeers {
			if ma, err := multiaddr.NewMultiaddr(peerAddr); err == nil {
				if peerInfo, err := peer.AddrInfoFromP2pAddr(ma); err == nil {
					// Add to peerstore with longer TTL for peer exchange
					n.host.Peerstore().AddAddrs(peerInfo.ID, peerInfo.Addrs, time.Hour*24)
					n.logger.ComponentDebug(logging.ComponentNode, "Added peer to peerstore",
						zap.String("peer", peerInfo.ID.String()))
				}
			}
		}
	}

	// Initialize discovery manager with peer exchange protocol
	n.discoveryManager = discovery.NewManager(h, nil, n.logger.Logger)
	n.discoveryManager.StartProtocolHandler()

	n.logger.ComponentInfo(logging.ComponentNode, "LibP2P host started successfully - using active peer exchange discovery")

	// Start peer discovery and monitoring
	n.startPeerDiscovery()

	n.logger.ComponentInfo(logging.ComponentLibP2P, "LibP2P host started",
		zap.String("peer_id", h.ID().String()))

	return nil
}

// loadOrCreateIdentity loads an existing identity or creates a new one
// loadOrCreateIdentity loads an existing identity or creates a new one
func (n *Node) loadOrCreateIdentity() (crypto.PrivKey, error) {
	identityFile := filepath.Join(n.config.Node.DataDir, "identity.key")

	// Expand ~ in data directory path
	identityFile = os.ExpandEnv(identityFile)
	if strings.HasPrefix(identityFile, "~") {
		home, err := os.UserHomeDir()
		if err != nil {
			return nil, fmt.Errorf("failed to determine home directory: %w", err)
		}
		identityFile = filepath.Join(home, identityFile[1:])
	}

	// Try to load existing identity using the shared package
	if _, err := os.Stat(identityFile); err == nil {
		info, err := encryption.LoadIdentity(identityFile)
		if err != nil {
			n.logger.Warn("Failed to load existing identity, creating new one", zap.Error(err))
		} else {
			n.logger.ComponentInfo(logging.ComponentNode, "Loaded existing identity",
				zap.String("file", identityFile),
				zap.String("peer_id", info.PeerID.String()))
			return info.PrivateKey, nil
		}
	}

	// Create new identity using shared package
	n.logger.Info("Creating new identity", zap.String("file", identityFile))
	info, err := encryption.GenerateIdentity()
	if err != nil {
		return nil, fmt.Errorf("failed to generate identity: %w", err)
	}

	// Save identity using shared package
	if err := encryption.SaveIdentity(info, identityFile); err != nil {
		return nil, fmt.Errorf("failed to save identity: %w", err)
	}

	n.logger.Info("Identity saved",
		zap.String("file", identityFile),
		zap.String("peer_id", info.PeerID.String()))

	return info.PrivateKey, nil
}

// GetPeerID returns the peer ID of this node
func (n *Node) GetPeerID() string {
	if n.host == nil {
		return ""
	}
	return n.host.ID().String()
}

// startPeerDiscovery starts periodic peer discovery for the node
func (n *Node) startPeerDiscovery() {
	if n.discoveryManager == nil {
		n.logger.ComponentWarn(logging.ComponentNode, "Discovery manager not initialized")
		return
	}

	// Start the discovery manager with config from node config
	discoveryConfig := discovery.Config{
		DiscoveryInterval: n.config.Discovery.DiscoveryInterval,
		MaxConnections:    n.config.Node.MaxConnections,
	}

	if err := n.discoveryManager.Start(discoveryConfig); err != nil {
		n.logger.ComponentWarn(logging.ComponentNode, "Failed to start discovery manager", zap.Error(err))
		return
	}

	n.logger.ComponentInfo(logging.ComponentNode, "Peer discovery manager started",
		zap.Duration("interval", discoveryConfig.DiscoveryInterval),
		zap.Int("max_connections", discoveryConfig.MaxConnections))
}

// stopPeerDiscovery stops peer discovery
func (n *Node) stopPeerDiscovery() {
	if n.discoveryManager != nil {
		n.discoveryManager.Stop()
	}
	n.logger.ComponentInfo(logging.ComponentNode, "Peer discovery stopped")
}

// getListenAddresses returns the current listen addresses as strings
// Stop stops the node and all its services
func (n *Node) Stop() error {
	n.logger.ComponentInfo(logging.ComponentNode, "Stopping network node")

	// Stop HTTP Gateway server
	if n.apiGatewayServer != nil {
		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
		defer cancel()
		_ = n.apiGatewayServer.Shutdown(ctx)
	}

	// Close Gateway client
	if n.apiGateway != nil {
		n.apiGateway.Close()
	}

	// Stop SNI Gateway
	if n.sniGateway != nil {
		if err := n.sniGateway.Stop(); err != nil {
			n.logger.ComponentWarn(logging.ComponentNode, "SNI Gateway stop error", zap.Error(err))
		}
	}

	// Stop cluster discovery
	if n.clusterDiscovery != nil {
		n.clusterDiscovery.Stop()
	}

	// Stop peer reconnection loop
	if n.peerDiscoveryCancel != nil {
		n.peerDiscoveryCancel()
	}

	// Stop peer discovery
	n.stopPeerDiscovery()

	// Stop LibP2P host
	if n.host != nil {
		n.host.Close()
	}

	// Stop RQLite
	if n.rqliteAdapter != nil {
		n.rqliteAdapter.Close()
	}
	if n.rqliteManager != nil {
		_ = n.rqliteManager.Stop()
	}

	n.logger.ComponentInfo(logging.ComponentNode, "Network node stopped")
	return nil
}

// startHTTPGateway initializes and starts the full API gateway with auth, pubsub, and API endpoints
func (n *Node) startHTTPGateway(ctx context.Context) error {
	if !n.config.HTTPGateway.Enabled {
		n.logger.ComponentInfo(logging.ComponentNode, "HTTP Gateway disabled in config")
		return nil
	}

	// Create separate logger for gateway
	logFile := filepath.Join(os.ExpandEnv(n.config.Node.DataDir), "..", "logs", "gateway.log")

	// Ensure logs directory exists
	logsDir := filepath.Dir(logFile)
	if err := os.MkdirAll(logsDir, 0755); err != nil {
		return fmt.Errorf("failed to create logs directory: %w", err)
	}

	gatewayLogger, err := logging.NewFileLogger(logging.ComponentGeneral, logFile, false)
	if err != nil {
		return fmt.Errorf("failed to create gateway logger: %w", err)
	}

	// Create full API Gateway for auth, pubsub, rqlite, and API endpoints
	// This replaces both the old reverse proxy gateway and the standalone gateway
	gwCfg := &gateway.Config{
		ListenAddr:      n.config.HTTPGateway.ListenAddr,
		ClientNamespace: n.config.HTTPGateway.ClientNamespace,
		BootstrapPeers:  n.config.Discovery.BootstrapPeers,
		RQLiteDSN:       n.config.HTTPGateway.RQLiteDSN,
		OlricServers:    n.config.HTTPGateway.OlricServers,
		OlricTimeout:    n.config.HTTPGateway.OlricTimeout,
		IPFSClusterAPIURL: n.config.HTTPGateway.IPFSClusterAPIURL,
		IPFSAPIURL:       n.config.HTTPGateway.IPFSAPIURL,
		IPFSTimeout:      n.config.HTTPGateway.IPFSTimeout,
		// HTTPS/TLS configuration
		EnableHTTPS: n.config.HTTPGateway.HTTPS.Enabled,
		DomainName:  n.config.HTTPGateway.HTTPS.Domain,
		TLSCacheDir: n.config.HTTPGateway.HTTPS.CacheDir,
	}

	apiGateway, err := gateway.New(gatewayLogger, gwCfg)
	if err != nil {
		return fmt.Errorf("failed to create full API gateway: %w", err)
	}

	n.apiGateway = apiGateway

	// Check if HTTPS is enabled and set up certManager BEFORE starting goroutine
	// This ensures n.certManager is set before SNI gateway initialization checks it
	var certManager *autocert.Manager
	var tlsCacheDir string
	if gwCfg.EnableHTTPS && gwCfg.DomainName != "" {
		tlsCacheDir = gwCfg.TLSCacheDir
		if tlsCacheDir == "" {
			tlsCacheDir = "/home/debros/.orama/tls-cache"
		}

		// Create TLS configuration with Let's Encrypt autocert
		// Using STAGING environment to avoid rate limits during development/testing
		// TODO: Switch to production when ready (remove Client field)
		certManager = &autocert.Manager{
			Prompt:     autocert.AcceptTOS,
			HostPolicy: autocert.HostWhitelist(gwCfg.DomainName),
			Cache:      autocert.DirCache(tlsCacheDir),
			Email:      fmt.Sprintf("admin@%s", gwCfg.DomainName),
			Client: &acme.Client{
				DirectoryURL: "https://acme-staging-v02.api.letsencrypt.org/directory",
			},
		}

		// Store certificate manager for use by SNI gateway
		n.certManager = certManager
	}

	// Channel to signal when HTTP server is ready for ACME challenges
	httpReady := make(chan struct{})

	// Start API Gateway in a goroutine
	go func() {
		gatewayLogger.ComponentInfo(logging.ComponentGateway, "Starting full API gateway",
			zap.String("listen_addr", gwCfg.ListenAddr),
		)

		// Check if HTTPS is enabled
		if gwCfg.EnableHTTPS && gwCfg.DomainName != "" && certManager != nil {
			// Start HTTPS server with automatic certificate provisioning
			gatewayLogger.ComponentInfo(logging.ComponentGateway, "HTTPS enabled, starting secure gateway",
				zap.String("domain", gwCfg.DomainName),
			)

			// Determine HTTPS and HTTP ports
			httpsPort := 443
			httpPort := 80

			// Start HTTP server for ACME challenges and redirects
			// certManager.HTTPHandler() must be the main handler, with a fallback for other requests
			httpServer := &http.Server{
				Addr: fmt.Sprintf(":%d", httpPort),
				Handler: certManager.HTTPHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
					// Fallback for non-ACME requests: redirect to HTTPS
					target := fmt.Sprintf("https://%s%s", r.Host, r.URL.RequestURI())
					http.Redirect(w, r, target, http.StatusMovedPermanently)
				})),
			}

			// Create HTTP listener first to ensure port 80 is bound before signaling ready
			httpListener, err := net.Listen("tcp", fmt.Sprintf(":%d", httpPort))
			if err != nil {
				gatewayLogger.ComponentError(logging.ComponentGateway, "failed to bind HTTP listener for ACME", zap.Error(err))
				close(httpReady) // Signal even on failure so SNI goroutine doesn't hang
				return
			}
			gatewayLogger.ComponentInfo(logging.ComponentGateway, "HTTP server ready for ACME challenges", zap.Int("port", httpPort))

			// Start HTTP server in background for ACME challenges
			go func() {
				if err := httpServer.Serve(httpListener); err != nil && err != http.ErrServerClosed {
					gatewayLogger.ComponentError(logging.ComponentGateway, "HTTP server error", zap.Error(err))
				}
			}()

		// Pre-provision the certificate BEFORE starting HTTPS server
		// This ensures we don't accept HTTPS connections without a valid certificate
		gatewayLogger.ComponentInfo(logging.ComponentGateway, "Pre-provisioning TLS certificate...",
			zap.String("domain", gwCfg.DomainName),
		)

		// Use a timeout context for certificate provisioning
		// If Let's Encrypt is rate-limited or unreachable, don't block forever
		certCtx, certCancel := context.WithTimeout(context.Background(), 30*time.Second)
		defer certCancel()

		certReq := &tls.ClientHelloInfo{
			ServerName: gwCfg.DomainName,
		}

		// Try to get certificate with timeout
		certProvisionChan := make(chan error, 1)
		go func() {
			_, err := certManager.GetCertificate(certReq)
			certProvisionChan <- err
		}()

		var certErr error
		select {
		case err := <-certProvisionChan:
			certErr = err
		case <-certCtx.Done():
			certErr = fmt.Errorf("certificate provisioning timeout (Let's Encrypt may be rate-limited or unreachable)")
		}

		if certErr != nil {
			gatewayLogger.ComponentError(logging.ComponentGateway, "Failed to provision TLS certificate - HTTPS disabled",
				zap.String("domain", gwCfg.DomainName),
				zap.Error(certErr),
			)
			// Signal ready for SNI goroutine (even though we're failing)
			close(httpReady)

			// HTTP server on port 80 is already running, but it's configured to redirect to HTTPS
			// Replace its handler to serve the gateway directly instead of redirecting
			httpServer.Handler = apiGateway.Routes()
			
			gatewayLogger.ComponentInfo(logging.ComponentGateway, "HTTP gateway available on port 80 only",
				zap.String("port", "80"),
			)
			return
		}

		gatewayLogger.ComponentInfo(logging.ComponentGateway, "TLS certificate provisioned successfully",
			zap.String("domain", gwCfg.DomainName),
		)

		// Signal that HTTP server is ready for ACME challenges
		close(httpReady)

			tlsConfig := &tls.Config{
				MinVersion:     tls.VersionTLS12,
				GetCertificate: certManager.GetCertificate,
			}

			// Start HTTPS server
			httpsServer := &http.Server{
				Addr:      fmt.Sprintf(":%d", httpsPort),
				TLSConfig: tlsConfig,
				Handler:   apiGateway.Routes(),
			}

			n.apiGatewayServer = httpsServer

			listener, err := tls.Listen("tcp", fmt.Sprintf(":%d", httpsPort), tlsConfig)
			if err != nil {
				gatewayLogger.ComponentError(logging.ComponentGateway, "failed to create TLS listener", zap.Error(err))
				return
			}

			gatewayLogger.ComponentInfo(logging.ComponentGateway, "HTTPS gateway listener bound",
				zap.String("domain", gwCfg.DomainName),
				zap.Int("port", httpsPort),
			)

			// Serve HTTPS
			if err := httpsServer.Serve(listener); err != nil && err != http.ErrServerClosed {
				gatewayLogger.ComponentError(logging.ComponentGateway, "HTTPS Gateway error", zap.Error(err))
			}
		} else {
			// No HTTPS - signal ready immediately (no ACME needed)
			close(httpReady)

			// Start plain HTTP server
			server := &http.Server{
				Addr:    gwCfg.ListenAddr,
				Handler: apiGateway.Routes(),
			}

			n.apiGatewayServer = server

			// Try to bind listener
			ln, err := net.Listen("tcp", gwCfg.ListenAddr)
			if err != nil {
				gatewayLogger.ComponentError(logging.ComponentGateway, "failed to bind API gateway listener", zap.Error(err))
				return
			}

			gatewayLogger.ComponentInfo(logging.ComponentGateway, "API gateway listener bound", zap.String("listen_addr", ln.Addr().String()))

			// Serve HTTP
			if err := server.Serve(ln); err != nil && err != http.ErrServerClosed {
				gatewayLogger.ComponentError(logging.ComponentGateway, "API Gateway error", zap.Error(err))
			}
		}
	}()

	// Initialize and start SNI gateway if HTTPS is enabled and SNI is configured
	// This runs in a separate goroutine that waits for HTTP server to be ready
	if n.config.HTTPGateway.SNI.Enabled && n.certManager != nil {
		go func() {
			// Wait for HTTP server to be ready for ACME challenges
			gatewayLogger.ComponentInfo(logging.ComponentGateway, "Waiting for HTTP server before SNI initialization...")
			<-httpReady
			
			gatewayLogger.ComponentInfo(logging.ComponentGateway, "Initializing SNI gateway",
				zap.String("listen_addr", n.config.HTTPGateway.SNI.ListenAddr),
			)

			// Provision the certificate from Let's Encrypt cache
			// This ensures the certificate file is downloaded and cached
			domain := n.config.HTTPGateway.HTTPS.Domain
			if domain != "" {
				gatewayLogger.ComponentInfo(logging.ComponentGateway, "Provisioning certificate for SNI",
					zap.String("domain", domain))
				
				certReq := &tls.ClientHelloInfo{
					ServerName: domain,
				}
				if tlsCert, err := n.certManager.GetCertificate(certReq); err != nil {
					gatewayLogger.ComponentError(logging.ComponentGateway, "Failed to provision certificate for SNI", 
						zap.String("domain", domain), zap.Error(err))
					return // Can't start SNI without certificate
				} else {
					gatewayLogger.ComponentInfo(logging.ComponentGateway, "Certificate provisioned for SNI", 
						zap.String("domain", domain))

					// Extract certificate to PEM files for SNI gateway
					// SNI gateway needs standard PEM cert files, not autocert cache format
					tlsCacheDir := n.config.HTTPGateway.HTTPS.CacheDir
					if tlsCacheDir == "" {
						tlsCacheDir = "/home/debros/.orama/tls-cache"
					}

					certPath := filepath.Join(tlsCacheDir, domain+".crt")
					keyPath := filepath.Join(tlsCacheDir, domain+".key")

					if err := extractPEMFromTLSCert(tlsCert, certPath, keyPath); err != nil {
						gatewayLogger.ComponentError(logging.ComponentGateway, "Failed to extract PEM from TLS cert for SNI", 
							zap.Error(err))
						return // Can't start SNI without PEM files
					}
					gatewayLogger.ComponentInfo(logging.ComponentGateway, "PEM certificates extracted for SNI", 
						zap.String("cert_path", certPath), zap.String("key_path", keyPath))
				}
			} else {
				gatewayLogger.ComponentError(logging.ComponentGateway, "No domain configured for SNI certificate")
				return
			}

			// Create SNI config with certificate files
			sniCfg := n.config.HTTPGateway.SNI

			// Use the same gateway logger for SNI gateway (writes to gateway.log)
			sniGateway, err := gateway.NewTCPSNIGateway(gatewayLogger, &sniCfg)
			if err != nil {
				gatewayLogger.ComponentError(logging.ComponentGateway, "Failed to initialize SNI gateway", zap.Error(err))
				return
			}

			n.sniGateway = sniGateway
			gatewayLogger.ComponentInfo(logging.ComponentGateway, "SNI gateway initialized, starting...")

			// Start SNI gateway (this blocks until shutdown)
			if err := n.sniGateway.Start(ctx); err != nil {
				gatewayLogger.ComponentError(logging.ComponentGateway, "SNI Gateway error", zap.Error(err))
			}
		}()
	}

	return nil
}

// extractPEMFromTLSCert extracts certificate and private key from tls.Certificate to PEM files
func extractPEMFromTLSCert(tlsCert *tls.Certificate, certPath, keyPath string) error {
	if tlsCert == nil || len(tlsCert.Certificate) == 0 {
		return fmt.Errorf("invalid tls certificate")
	}

	// Write certificate chain to PEM file
	certFile, err := os.Create(certPath)
	if err != nil {
		return fmt.Errorf("failed to create cert file: %w", err)
	}
	defer certFile.Close()

	// Write all certificates in the chain
	for _, certBytes := range tlsCert.Certificate {
		if err := pem.Encode(certFile, &pem.Block{
			Type:  "CERTIFICATE",
			Bytes: certBytes,
		}); err != nil {
			return fmt.Errorf("failed to encode certificate: %w", err)
		}
	}

	// Write private key to PEM file
	if tlsCert.PrivateKey == nil {
		return fmt.Errorf("private key is nil")
	}

	keyFile, err := os.Create(keyPath)
	if err != nil {
		return fmt.Errorf("failed to create key file: %w", err)
	}
	defer keyFile.Close()

	// Handle different key types
	var keyBytes []byte
	switch key := tlsCert.PrivateKey.(type) {
	case *x509.Certificate:
		keyBytes, err = x509.MarshalPKCS8PrivateKey(key)
		if err != nil {
			return fmt.Errorf("failed to marshal private key: %w", err)
		}
	default:
		// Try to marshal as PKCS8
		keyBytes, err = x509.MarshalPKCS8PrivateKey(tlsCert.PrivateKey)
		if err != nil {
			return fmt.Errorf("failed to marshal private key: %w", err)
		}
	}

	if err := pem.Encode(keyFile, &pem.Block{
		Type:  "PRIVATE KEY",
		Bytes: keyBytes,
	}); err != nil {
		return fmt.Errorf("failed to encode private key: %w", err)
	}

	// Set proper permissions
	os.Chmod(certPath, 0644)
	os.Chmod(keyPath, 0600)

	return nil
}

// Starts the network node
func (n *Node) Start(ctx context.Context) error {
	n.logger.Info("Starting network node", zap.String("data_dir", n.config.Node.DataDir))

	// Expand ~ in data directory path
	dataDir := n.config.Node.DataDir
	dataDir = os.ExpandEnv(dataDir)
	if strings.HasPrefix(dataDir, "~") {
		home, err := os.UserHomeDir()
		if err != nil {
			return fmt.Errorf("failed to determine home directory: %w", err)
		}
		dataDir = filepath.Join(home, dataDir[1:])
	}

	// Create data directory
	if err := os.MkdirAll(dataDir, 0755); err != nil {
		return fmt.Errorf("failed to create data directory: %w", err)
	}

	// Start HTTP Gateway first (doesn't depend on other services)
	if err := n.startHTTPGateway(ctx); err != nil {
		n.logger.ComponentWarn(logging.ComponentNode, "Failed to start HTTP Gateway", zap.Error(err))
		// Don't fail node startup if gateway fails
	}

	// Start LibP2P host first (needed for cluster discovery)
	if err := n.startLibP2P(); err != nil {
		return fmt.Errorf("failed to start LibP2P: %w", err)
	}

	// Initialize IPFS Cluster configuration if enabled
	if n.config.Database.IPFS.ClusterAPIURL != "" {
		if err := n.startIPFSClusterConfig(); err != nil {
			n.logger.ComponentWarn(logging.ComponentNode, "Failed to initialize IPFS Cluster config", zap.Error(err))
			// Don't fail node startup if cluster config fails
		}
	}

	// Start RQLite with cluster discovery
	if err := n.startRQLite(ctx); err != nil {
		return fmt.Errorf("failed to start RQLite: %w", err)
	}

	// Get listen addresses for logging
	var listenAddrs []string
	for _, addr := range n.host.Addrs() {
		listenAddrs = append(listenAddrs, addr.String())
	}

	n.logger.ComponentInfo(logging.ComponentNode, "Network node started successfully",
		zap.String("peer_id", n.host.ID().String()),
		zap.Strings("listen_addrs", listenAddrs),
	)

	n.startConnectionMonitoring()

	return nil
}

// startIPFSClusterConfig initializes and ensures IPFS Cluster configuration
func (n *Node) startIPFSClusterConfig() error {
	n.logger.ComponentInfo(logging.ComponentNode, "Initializing IPFS Cluster configuration")

	// Create config manager
	cm, err := ipfs.NewClusterConfigManager(n.config, n.logger.Logger)
	if err != nil {
		return fmt.Errorf("failed to create cluster config manager: %w", err)
	}
	n.clusterConfigManager = cm

	// Fix IPFS config addresses (localhost -> 127.0.0.1) before ensuring cluster config
	if err := cm.FixIPFSConfigAddresses(); err != nil {
		n.logger.ComponentWarn(logging.ComponentNode, "Failed to fix IPFS config addresses", zap.Error(err))
		// Don't fail startup if config fix fails - cluster config will handle it
	}

	// Ensure configuration exists and is correct
	if err := cm.EnsureConfig(); err != nil {
		return fmt.Errorf("failed to ensure cluster config: %w", err)
	}

	// Try to repair peer configuration automatically
	// This will be retried periodically if peer is not available yet
	if success, err := cm.RepairPeerConfiguration(); err != nil {
		n.logger.ComponentWarn(logging.ComponentNode, "Failed to repair peer configuration, will retry later", zap.Error(err))
	} else if success {
		n.logger.ComponentInfo(logging.ComponentNode, "Peer configuration repaired successfully")
	} else {
		n.logger.ComponentDebug(logging.ComponentNode, "Peer not available yet, will retry periodically")
	}

	n.logger.ComponentInfo(logging.ComponentNode, "IPFS Cluster configuration initialized")
	return nil
}