package main

import (
	"flag"
	"log"
	"os"
	"os/signal"
	"sync"
	"syscall"
	"time"

	"go-ts/pkg/ts3client"
	"go-ts/pkg/xai"
)

// VoiceSession represents an active xAI voice session for a user
type VoiceSession struct {
	ClientID    uint16
	Nickname    string
	XAI         *xai.Client
	AudioBuffer []int16       // Buffer to accumulate audio samples
	AudioQueue  chan []int16  // Queue for sending audio with proper timing
	done        chan struct{} // Signal to stop audio sender
}

// Bot manages the TeamSpeak connection and xAI sessions
type Bot struct {
	ts3    *ts3client.Client
	apiKey string
	voice  string
	prompt string

	selfID     uint16 // Our own ClientID
	sessions   map[uint16]*VoiceSession
	sessionsMu sync.RWMutex
}

func main() {
	serverAddr := flag.String("server", "127.0.0.1:9987", "TeamSpeak 3 Server Address")
	nickname := flag.String("nickname", "GrokBot", "Bot nickname")
	voice := flag.String("voice", xai.VoiceAra, "xAI voice (Ara, Rex, Sal, Eve, Leo)")
	flag.Parse()

	apiKey := os.Getenv("XAI_API_KEY")
	if apiKey == "" {
		log.Fatal("XAI_API_KEY environment variable not set")
	}

	log.Println("=== xAI Voice Bot for TeamSpeak ===")
	log.Printf("Server: %s", *serverAddr)
	log.Printf("Nickname: %s", *nickname)
	log.Printf("Voice: %s", *voice)

	bot := &Bot{
		apiKey:   apiKey,
		voice:    *voice,
		prompt:   "Eres Grok, un asistente de voz amigable y útil. Responde de forma concisa y natural.",
		sessions: make(map[uint16]*VoiceSession),
	}

	// Create TeamSpeak client
	bot.ts3 = ts3client.New(*serverAddr, ts3client.Config{
		Nickname: *nickname,
	})

	// Register event handlers
	bot.ts3.On(ts3client.EventConnected, func(e *ts3client.ConnectedEvent) {
		bot.selfID = e.ClientID // Store our own ID
		log.Printf("✓ Conectado a TeamSpeak! ClientID=%d, Server=%s", e.ClientID, e.ServerName)
	})

	bot.ts3.On(ts3client.EventChannelList, func(e *ts3client.ChannelListEvent) {
		log.Printf("✓ %d canales disponibles", len(e.Channels))
	})

	bot.ts3.On(ts3client.EventClientEnter, func(e *ts3client.ClientEnterEvent) {
		log.Printf("→ Usuario entró: %s (ID=%d)", e.Nickname, e.ClientID)

		// Don't create session for ourselves (compare by ID, not nickname)
		if e.ClientID == bot.selfID {
			log.Printf("   (Soy yo, ignorando)")
			return
		}

		// Create xAI session for this user
		go bot.createSession(e.ClientID, e.Nickname)
	})

	bot.ts3.On(ts3client.EventClientLeft, func(e *ts3client.ClientLeftEvent) {
		log.Printf("← Usuario salió: ID=%d (%s)", e.ClientID, e.Reason)

		// Close xAI session for this user
		bot.closeSession(e.ClientID)
	})

	bot.ts3.On(ts3client.EventAudio, func(e *ts3client.AudioEvent) {
		// Forward audio from TeamSpeak to all xAI sessions
		// In a real implementation, you'd want to track which user
		// is speaking and only send to their session
		bot.sessionsMu.RLock()
		for _, session := range bot.sessions {
			if session.XAI != nil && session.XAI.IsConnected() {
				session.XAI.SendAudio(e.PCM)
			}
		}
		bot.sessionsMu.RUnlock()
	})

	bot.ts3.On(ts3client.EventError, func(e *ts3client.ErrorEvent) {
		if e.ID != "0" {
			log.Printf("! Error del servidor: [%s] %s", e.ID, e.Message)
		}
	})

	// Handle shutdown
	go func() {
		sigChan := make(chan os.Signal, 1)
		signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
		<-sigChan
		log.Println("Cerrando...")

		// Close all xAI sessions
		bot.sessionsMu.Lock()
		for _, session := range bot.sessions {
			if session.XAI != nil {
				session.XAI.Close()
			}
		}
		bot.sessionsMu.Unlock()

		bot.ts3.Disconnect()
		// os.Exit(0)
	}()

	// Connect to TeamSpeak
	if err := bot.ts3.Connect(); err != nil {
		log.Fatalf("Error de conexión: %v", err)
	}
}

// createSession creates a new xAI voice session for a user
func (b *Bot) createSession(clientID uint16, nickname string) {
	log.Printf("[Session] Creando sesión xAI para %s...", nickname)

	// Create session with audio queue
	session := &VoiceSession{
		ClientID:    clientID,
		Nickname:    nickname,
		AudioBuffer: make([]int16, 0, 960*10),
		AudioQueue:  make(chan []int16, 500), // Buffer up to 500 frames (~10 sec)
		done:        make(chan struct{}),
	}

	// Start audio sender goroutine with proper 20ms timing
	go b.audioSender(session)

	xaiClient := xai.New(b.apiKey)

	// Set up audio callback - buffer and queue in 960-sample chunks
	xaiClient.OnAudio(func(pcm []int16) {
		b.sessionsMu.Lock()
		session.AudioBuffer = append(session.AudioBuffer, pcm...)

		// Queue complete 960-sample frames
		for len(session.AudioBuffer) >= 960 {
			frame := make([]int16, 960)
			copy(frame, session.AudioBuffer[:960])
			session.AudioBuffer = session.AudioBuffer[960:]

			// Non-blocking send to queue
			select {
			case session.AudioQueue <- frame:
			default:
				// Queue full, drop frame
			}
		}
		b.sessionsMu.Unlock()
	})

	// Set up transcript callback for logging
	xaiClient.OnTranscript(func(text string) {
		log.Printf("[Grok] %s", text)
	})

	// Clear audio queue when user starts speaking (interruption)
	xaiClient.OnSpeechStarted(func() {
		b.sessionsMu.Lock()
		// Clear the buffer
		session.AudioBuffer = session.AudioBuffer[:0]
		// Drain the queue
		for len(session.AudioQueue) > 0 {
			<-session.AudioQueue
		}
		b.sessionsMu.Unlock()
		log.Printf("[Session] Audio queue cleared (user interruption)")
	})

	// Connect to xAI
	if err := xaiClient.Connect(); err != nil {
		log.Printf("[Session] Error conectando a xAI: %v", err)
		close(session.done)
		return
	}

	// Configure the session
	if err := xaiClient.ConfigureSession(b.voice, b.prompt); err != nil {
		log.Printf("[Session] Error configurando sesión: %v", err)
		xaiClient.Close()
		close(session.done)
		return
	}

	// Store the xAI client in session
	session.XAI = xaiClient

	b.sessionsMu.Lock()
	b.sessions[clientID] = session
	b.sessionsMu.Unlock()

	log.Printf("[Session] ✓ Sesión xAI activa para %s", nickname)
}

// audioSender sends audio frames to TeamSpeak with proper 20ms timing
func (b *Bot) audioSender(session *VoiceSession) {
	ticker := time.NewTicker(20 * time.Millisecond)
	defer ticker.Stop()

	for {
		select {
		case <-session.done:
			return
		case <-ticker.C:
			// Try to get a frame from the queue
			select {
			case frame := <-session.AudioQueue:
				if err := b.ts3.SendAudio(frame); err != nil {
					log.Printf("[Session] Error enviando audio: %v", err)
				}
			default:
				// No frame available, that's ok
			}
		}
	}
}

// closeSession closes an xAI session for a user
func (b *Bot) closeSession(clientID uint16) {
	b.sessionsMu.Lock()
	defer b.sessionsMu.Unlock()

	if session, ok := b.sessions[clientID]; ok {
		log.Printf("[Session] Cerrando sesión xAI para %s", session.Nickname)
		if session.XAI != nil {
			session.XAI.Close()
		}
		delete(b.sessions, clientID)
	}
}