import assert from 'node:assert/strict'
import fs from 'node:fs'
import test from 'node:test'

import { shouldReplayRealtimeEvents } from './realtime-event-service.js'

/**
 * 回归：整页刷新后大厅列表重复、可抢订单数越刷越多。
 *
 * 根因是新连接（lastEventId=0）也会补发最近 500 条历史事件。大厅 upsert 广播带的是
 * 当时的工单快照，被重新打进刚加载的列表后，已抢走/已出队的订单会复活并被插到第 1 页，
 * 前端还会按「插入行」把 pagination.total 加一。
 */
test('新连接（lastEventId=0）不补发历史事件，避免旧大厅快照复活订单', () => {
  assert.equal(shouldReplayRealtimeEvents(0), false)
  assert.equal(shouldReplayRealtimeEvents(Number.NaN), false)
  assert.equal(shouldReplayRealtimeEvents(-1), false)
})

test('断线重连（带 Last-Event-ID）才补发事件', () => {
  assert.equal(shouldReplayRealtimeEvents(1), true)
  assert.equal(shouldReplayRealtimeEvents(3993659), true)
})

test('补发窗口取最新的一段，而不是最旧的一段', () => {
  const source = fs.readFileSync(
    new URL('../../repositories/realtime-event-repo.ts', import.meta.url),
    'utf8',
  )
  const block = source.slice(
    source.indexOf('export async function listRealtimeEventsAfter('),
    source.indexOf('\n}', source.indexOf('export async function listRealtimeEventsAfter(')),
  )
  assert.ok(block.length > 0, 'listRealtimeEventsAfter 片段必须存在')
  assert.ok(
    /ORDER BY id DESC\s+LIMIT \$2\s+\)\s*replay_window\s+ORDER BY id ASC/s.test(block),
    '补发必须「内层 id DESC 取最新 N 条、外层 id ASC 回放」；否则断线久了窗口会停在旧事件上',
  )
})

test('补发窗口溢出时改为让客户端整体重拉', () => {
  const source = fs.readFileSync(new URL('./realtime-event-service.ts', import.meta.url), 'utf8')
  const replayBlock = source.slice(
    source.indexOf('async function replayEvents('),
    source.indexOf('function mapStoredEvent('),
  )
  assert.ok(replayBlock.length > 0, 'replayEvents 片段必须存在')
  assert.ok(
    replayBlock.includes('events.length >= REALTIME_REPLAY_EVENT_LIMIT'),
    '补发窗口被拿满时必须判定为溢出，不能继续逐条套用旧快照',
  )
  assert.ok(
    replayBlock.includes("'resync'"),
    '溢出时要给客户端发 resync，让列表整体重拉（接口才是权威数据源）',
  )
})