package svc

import (
	"sync"

	"github.com/gorilla/websocket"
)

type Client struct {
	SessionID string
	Conn      *websocket.Conn
	sendMu    sync.Mutex
}

type Hub struct {
	mu      sync.RWMutex
	clients map[string]*Client
}

func NewHub() *Hub {
	return &Hub{clients: make(map[string]*Client)}
}

func (h *Hub) Add(c *Client) {
	h.mu.Lock()
	defer h.mu.Unlock()
	if old, ok := h.clients[c.SessionID]; ok && old.Conn != c.Conn {
		_ = old.Conn.Close()
	}
	h.clients[c.SessionID] = c
}

func (h *Hub) Remove(sessionID string, conn *websocket.Conn) {
	h.mu.Lock()
	defer h.mu.Unlock()
	cur, ok := h.clients[sessionID]
	if !ok {
		return
	}
	if conn != nil && cur.Conn != conn {
		return
	}
	delete(h.clients, sessionID)
}

func (h *Hub) Send(sessionID string, payload []byte) bool {
	h.mu.RLock()
	c, ok := h.clients[sessionID]
	h.mu.RUnlock()
	if !ok {
		return false
	}

	c.sendMu.Lock()
	defer c.sendMu.Unlock()
	if err := c.Conn.WriteMessage(websocket.TextMessage, payload); err != nil {
		_ = c.Conn.Close()
		h.Remove(sessionID, c.Conn)
		return false
	}
	return true
}