import { closeRouter, getProducer, getTransport } from './mediasoup.js'

const TTL_MS = 60_000
const sessions = new Map()

export const createSession = (userId, label = '') => {
  const id = crypto.randomUUID()
  const session = {
    id,
    userId,
    label: (label || 'Live').trim() || 'Live',
    lat: 0,
    lng: 0,
    updatedAt: Date.now(),
    routerId: null,
    producerId: null,
    transportId: null,
  }
  sessions.set(id, session)
  return session
}

export const getLiveSession = (id) => sessions.get(id)

export const getActiveSessionByUserId = (userId) => {
  const now = Date.now()
  for (const s of sessions.values()) {
    if (s.userId === userId && now - s.updatedAt <= TTL_MS) return s
  }
}

export const updateLiveSession = (id, updates) => {
  const session = sessions.get(id)
  if (!session) return
  const now = Date.now()
  if (Number.isFinite(updates.lat)) session.lat = updates.lat
  if (Number.isFinite(updates.lng)) session.lng = updates.lng
  if (updates.routerId !== undefined) session.routerId = updates.routerId
  if (updates.producerId !== undefined) session.producerId = updates.producerId
  if (updates.transportId !== undefined) session.transportId = updates.transportId
  session.updatedAt = now
}

export const deleteLiveSession = (id) => sessions.delete(id)

export const clearSessions = () => sessions.clear()

const cleanupSession = async (session) => {
  if (session.producerId) {
    const producer = getProducer(session.producerId)
    producer?.close()
  }
  if (session.transportId) {
    const transport = getTransport(session.transportId)
    transport?.close()
  }
  if (session.routerId) {
    await closeRouter(session.id).catch((err) => {
      console.error(`[liveSessions] Error closing router for expired session ${session.id}:`, err)
    })
  }
}

export const getActiveSessions = async () => {
  const now = Date.now()
  const active = []
  const expired = []

  for (const session of sessions.values()) {
    if (now - session.updatedAt <= TTL_MS) {
      active.push({
        id: session.id,
        userId: session.userId,
        label: session.label,
        lat: session.lat,
        lng: session.lng,
        updatedAt: session.updatedAt,
        hasStream: Boolean(session.producerId),
      })
    }
    else {
      expired.push(session)
    }
  }

  for (const session of expired) {
    await cleanupSession(session)
    sessions.delete(session.id)
  }

  return active
}