package api

import (
	"encoding/json"
	"log"
	"sync"
	"time"

	"git.rouggy.com/rouggy/ShackMaster/pkg/protocol"
	"github.com/gorilla/websocket"
)

type Hub struct {
	clients    map[*Client]bool
	broadcast  chan *protocol.WebSocketMessage
	register   chan *Client
	unregister chan *Client
	mu         sync.RWMutex
}

type Client struct {
	hub  *Hub
	conn *websocket.Conn
	send chan *protocol.WebSocketMessage
}

func NewHub() *Hub {
	return &Hub{
		clients:    make(map[*Client]bool),
		broadcast:  make(chan *protocol.WebSocketMessage, 256),
		register:   make(chan *Client),
		unregister: make(chan *Client),
	}
}

func (h *Hub) Run() {
	for {
		select {
		case client := <-h.register:
			h.mu.Lock()
			h.clients[client] = true
			h.mu.Unlock()
			log.Printf("Client connected, total: %d", len(h.clients))

		case client := <-h.unregister:
			h.mu.Lock()
			if _, ok := h.clients[client]; ok {
				delete(h.clients, client)
				close(client.send)
			}
			h.mu.Unlock()
			log.Printf("Client disconnected, total: %d", len(h.clients))

		case message := <-h.broadcast:
			h.mu.RLock()
			for client := range h.clients {
				select {
				case client.send <- message:
				default:
					// Client's send buffer is full, close it
					h.mu.RUnlock()
					h.unregister <- client
					h.mu.RLock()
				}
			}
			h.mu.RUnlock()
		}
	}
}

func (h *Hub) Broadcast(msg *protocol.WebSocketMessage) {
	h.broadcast <- msg
}

func (h *Hub) ClientCount() int {
	h.mu.RLock()
	defer h.mu.RUnlock()
	return len(h.clients)
}

const (
	writeWait      = 10 * time.Second
	pongWait       = 60 * time.Second
	pingPeriod     = (pongWait * 9) / 10
	maxMessageSize = 512 * 1024 // 512KB
)

func (c *Client) readPump() {
	defer func() {
		c.hub.unregister <- c
		c.conn.Close()
	}()

	c.conn.SetReadDeadline(time.Now().Add(pongWait))
	c.conn.SetReadLimit(maxMessageSize)
	c.conn.SetPongHandler(func(string) error {
		c.conn.SetReadDeadline(time.Now().Add(pongWait))
		return nil
	})

	for {
		var msg protocol.WebSocketMessage
		err := c.conn.ReadJSON(&msg)
		if err != nil {
			if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway, websocket.CloseAbnormalClosure) {
				log.Printf("WebSocket error: %v", err)
			}
			break
		}

		// Handle incoming commands from client
		log.Printf("Received message: type=%s, device=%s", msg.Type, msg.Device)

		// Commands are handled via REST API, not WebSocket
		// WebSocket is primarily for server -> client updates
		// Client should use REST endpoints for commands
	}
}

func (c *Client) writePump() {
	ticker := time.NewTicker(pingPeriod)
	defer func() {
		ticker.Stop()
		c.conn.Close()
	}()

	for {
		select {
		case message, ok := <-c.send:
			c.conn.SetWriteDeadline(time.Now().Add(writeWait))
			if !ok {
				// Hub closed the channel
				c.conn.WriteMessage(websocket.CloseMessage, []byte{})
				return
			}

			if err := c.conn.WriteJSON(message); err != nil {
				log.Printf("Error writing message: %v", err)
				return
			}

		case <-ticker.C:
			c.conn.SetWriteDeadline(time.Now().Add(writeWait))
			if err := c.conn.WriteMessage(websocket.PingMessage, nil); err != nil {
				return
			}
		}
	}
}

func ServeWs(hub *Hub, conn *websocket.Conn) {
	client := &Client{
		hub:  hub,
		conn: conn,
		send: make(chan *protocol.WebSocketMessage, 256),
	}

	client.hub.register <- client

	// Send initial status
	go func() {
		time.Sleep(100 * time.Millisecond)
		client.send <- &protocol.WebSocketMessage{
			Type:      protocol.MsgTypeStatus,
			Data:      map[string]string{"status": "connected"},
			Timestamp: time.Now(),
		}
	}()

	go client.writePump()
	go client.readPump()
}

// BroadcastStatusUpdate sends a status update to all connected clients
func (h *Hub) BroadcastStatusUpdate(status interface{}) {
	data, err := json.Marshal(status)
	if err != nil {
		log.Printf("Error marshaling status: %v", err)
		return
	}

	var statusMap map[string]interface{}
	if err := json.Unmarshal(data, &statusMap); err != nil {
		log.Printf("Error unmarshaling status: %v", err)
		return
	}

	h.Broadcast(&protocol.WebSocketMessage{
		Type:      protocol.MsgTypeUpdate,
		Data:      statusMap,
		Timestamp: time.Now(),
	})
}