import type { Response } from 'express'
import { logger } from '../utils/logger.js'

type NotebookEvent = {
  event: string
  path?: string
}

let clients: Response[] = []

export const eventBus = {
  addClient: (res: Response) => {
    clients.push(res)
    logger.info(`SSE client connected. Total clients: ${clients.length}`)
  },
  removeClient: (res: Response) => {
    clients = clients.filter((c) => c !== res)
    logger.info(`SSE client disconnected. Total clients: ${clients.length}`)
  },
  broadcast: (payload: NotebookEvent) => {
    const data = `data: ${JSON.stringify(payload)}

`
    logger.info(`Broadcasting to ${clients.length} clients: ${payload.event} - ${payload.path || ''}`)
    clients = clients.filter((client) => {
      try {
        client.write(data)
        return true
      } catch (error) {
        logger.warn('SSE client write failed, removing')
        return false
      }
    })
  },
}