import { createServer } from 'node:http'
import type { Duplex } from 'node:stream'

import { getRequestListener } from '@hono/node-server'
import type { WebSocketLike } from '@hocuspocus/server'
import crossws from 'crossws/adapters/node'

import { createApp } from './app.ts'
import { SESSION_COOKIE, SessionManager, isSameOrigin, readCookie } from './auth.ts'
import { Collab } from './collab.ts'
import { loadConfig } from './config.ts'
import { Storage } from './db.ts'
import { ImageStore } from './images.ts'

type ClientConnection = ReturnType<Collab['hocuspocus']['handleConnection']>

const config = loadConfig()
const storage = new Storage(config.databaseFile)
const sessions = new SessionManager(config.secret, config.password, config.sessionDays)
const collab = new Collab(storage, sessions)
await collab.start()

const app = createApp({ config, sessions, collab, images: new ImageStore(config.imagesDir) })
const server = createServer(getRequestListener(app.fetch))

const connections = new WeakMap<object, ClientConnection>()
const ws = crossws({
  hooks: {
    open(peer) {
      const connection = collab.hocuspocus.handleConnection(
        peer.websocket as unknown as WebSocketLike,
        peer.request as Request,
      )
      connections.set(peer, connection)
    },
    message(peer, message) {
      connections.get(peer)?.handleMessage(message.uint8Array())
    },
    close(peer, event) {
      connections.get(peer)?.handleClose({ code: event.code ?? 1000, reason: event.reason ?? '' })
      connections.delete(peer)
    },
    error(peer, error) {
      console.error('[boundless] websocket error', error)
    },
  },
})

server.on('upgrade', (request, socket: Duplex, head) => {
  const url = new URL(request.url ?? '/', 'http://localhost')
  const forwardedHost = request.headers['x-forwarded-host']
  const allowed =
    url.pathname === '/collab' &&
    isSameOrigin(request.headers.origin, [
      Array.isArray(forwardedHost) ? forwardedHost[0] : forwardedHost,
      request.headers.host,
    ]) &&
    sessions.verify(readCookie(request.headers.cookie, SESSION_COOKIE))

  if (!allowed) {
    socket.end('HTTP/1.1 401 Unauthorized\r\nConnection: close\r\nContent-Length: 0\r\n\r\n')
    return
  }
  void ws.handleUpgrade(request, socket, head)
})

server.listen(config.port, config.host, () => {
  console.log(`[boundless] 已启动 http://${config.host}:${config.port}`)
  console.log(`[boundless] 数据目录 ${config.dataDir}`)
  if (!config.staticDir) console.log('[boundless] 未托管前端页面（开发模式请访问 Vite 地址）')
})

let shuttingDown = false
async function shutdown() {
  if (shuttingDown) return
  shuttingDown = true
  server.close()
  // 先把还没写盘的修改落盘，再关闭数据库
  await collab.stop()
  await collab.hocuspocus.closeConnections()
  await new Promise((resolve) => setTimeout(resolve, 200))
  storage.close()
  process.exit(0)
}

process.on('SIGINT', () => void shutdown())
process.on('SIGTERM', () => void shutdown())