import type { ProjectEvent } from '#shared/types'

/** SSE：推送任务进度、写作增量、章节变更 */
export default defineEventHandler(async (event) => {
  const projectId = param(event)
  getProject(projectId)
  const stream = createEventStream(event)
  const send = (e: ProjectEvent) => { stream.push(JSON.stringify(e)).catch(() => {}) }
  const unsubscribe = subscribeProject(projectId, send)
  const run = getActiveRun(projectId)
  send({ type: 'pipeline', running: Boolean(run), message: run?.label })
  const heartbeat = setInterval(() => { stream.push({ event: 'ping', data: String(Date.now()) }).catch(() => {}) }, 20_000)
  stream.onClosed(async () => {
    clearInterval(heartbeat)
    unsubscribe()
    await stream.close()
  })
  return stream.send()
})