// ── Per-channel notification preferences (ENGAGEMENT.md Phase 3) ───────────
//
// The phase's acceptance criteria, one test apiece:
//
//   • the shipped Android app's flat `{streams:[…]}` PUT still round-trips,
//     INCLUDING the empty-array case its DTO comment warns about
//   • a per-channel PUT sets `email` without touching `push`
//   • a fresh user's email mode defaults `off`, and so does push
//
// …plus the two properties that make the projection safe to ship: the legacy
// wire shape is pinned BYTE-FOR-BYTE (the app cannot be changed from this side),
// and the invariant the two endpoints jointly maintain — a push pref with mode
// <> 'off' iff a `notification_subscriptions` row — is asserted from both
// directions rather than only from the one the code happens to take.
//
// Point the DB at a closed port before requiring anything: the registries reach
// utils/discordAnnounce, which builds the pool at require time.
process.env.DB_HOST = '127.0.0.1'
process.env.DB_PORT = '59999'

const { test, beforeEach, afterEach, after } = require('node:test')
const assert = require('node:assert/strict')

const registries = require('../src/modules/registries')
const channels = require('../src/engagement/channels')
const prefs = require('../src/model/notificationChannelPrefs/notificationChannelPrefs.model')
const prefsDb = require('../src/model/notificationChannelPrefs/notificationChannelPrefs.db')
const subs = require('../src/model/notificationSubs/notificationSubs.model')
const subsDb = require('../src/model/notificationSubs/notificationSubs.db')
const notifCtrl = require('../src/router/v1/auth/notifications.controller')
const db = require('../src/utils/db')

after(() => db.close())

const USER = 7
const PLAYER = { id: USER, role: 'player' }
const ADMIN = { id: USER, role: 'admin' }

// ── In-memory stand-ins for the two tables ─────────────────────────────────
//
// Both are stubbed at the `.db` layer, so the model's own fan-out logic — the
// part this phase actually adds — runs for real against them.
let prefRows // Map "<user> <id> <channel>" -> mode
let subRows // Set "<user> <id>"

function installStubs() {
  prefRows = new Map()
  subRows = new Set()

  prefsDb.listByUser = async (userId) =>
    [...prefRows.entries()]
      .filter(([k]) => k.startsWith(`${userId} `))
      .map(([k, mode]) => {
        const [, streamId, channel] = k.split(' ')
        return { stream_id: streamId, channel, mode }
      })
      .sort((a, b) => a.stream_id.localeCompare(b.stream_id) || a.channel.localeCompare(b.channel))

  prefsDb.upsert = async (userId, streamId, channel, mode) => {
    prefRows.set(`${userId} ${streamId} ${channel}`, mode)
  }

  prefsDb.offPushExcept = async (userId, keep) => {
    for (const [k, mode] of prefRows.entries()) {
      const [u, streamId, channel] = k.split(' ')
      if (Number(u) !== userId || channel !== 'push' || mode === 'off') continue
      if (!keep.includes(streamId)) prefRows.set(k, 'off')
    }
  }

  subsDb.listByUser = async (userId) =>
    [...subRows]
      .filter((k) => k.startsWith(`${userId} `))
      .map((k) => ({ stream_id: k.split(' ')[1] }))
      .sort((a, b) => a.stream_id.localeCompare(b.stream_id))

  subsDb.replaceForUser = async (userId, streams) => {
    for (const k of [...subRows]) if (k.startsWith(`${userId} `)) subRows.delete(k)
    for (const s of streams) subRows.add(`${userId} ${s}`)
  }
  subsDb.addForUser = async (userId, streamId) => subRows.add(`${userId} ${streamId}`)
  subsDb.removeForUser = async (userId, streamId) => subRows.delete(`${userId} ${streamId}`)
}

// The channel registry is populated by requiring the subsystem's door, exactly
// as app.js does. Requiring `channels` alone gets the empty map — that is the
// design, and doing it the other way here would hide a boot-order regression.
function registerChannels() {
  channels._reset()
  delete require.cache[require.resolve('../src/engagement/coreChannels')]
  // eslint-disable-next-line global-require
  require('../src/engagement/coreChannels')
}

beforeEach(() => {
  registries._reset()
  registries.registerCore()
  registerChannels()
  installStubs()
})

afterEach(() => {
  registries._reset()
  channels._reset()
})

const mockRes = () => ({
  statusCode: 200,
  body: null,
  status(c) { this.statusCode = c; return this },
  json(b) { this.body = b; return this },
})

const item = (surface, id) => surface.items.find((i) => i.id === id)

// ── Acceptance: the shipped app's wire shape ───────────────────────────────

test('the legacy subscriptions PUT round-trips byte-for-byte', async () => {
  const put = mockRes()
  await notifCtrl.putSubscriptions({ user: PLAYER, body: { streams: ['news.post', 'team.forum.post'] } }, put)

  // Byte-for-byte: the response is `{ streams: [...] }` and nothing else. The
  // Android DTO is frozen, so an extra key is as much a break as a missing one.
  assert.deepEqual(Object.keys(put.body), ['streams'])
  assert.deepEqual(put.body.streams.slice().sort(), ['news.post', 'team.forum.post'])

  const get = mockRes()
  await notifCtrl.getSubscriptions({ user: PLAYER }, get)
  assert.deepEqual(Object.keys(get.body), ['streams'])
  assert.deepEqual(get.body.streams, ['news.post', 'team.forum.post'])
})

test('the empty-array case its DTO comment warns about still clears the set', async () => {
  await notifCtrl.putSubscriptions({ user: PLAYER, body: { streams: ['news.post'] } }, mockRes())

  const cleared = mockRes()
  await notifCtrl.putSubscriptions({ user: PLAYER, body: { streams: [] } }, cleared)
  assert.deepEqual(cleared.body, { streams: [] })

  // And the projection cleared with it — the failure this test exists to catch
  // is a channel-prefs row left at 'instant' after the app said "none", which
  // would resurrect the subscription the next time anything read the new table.
  const surface = await prefs.getForUser(USER, PLAYER)
  assert.equal(item(surface, 'news.post').modes.push, 'off')
  assert.equal(subRows.size, 0)
})

test('unknown stream ids are still dropped, and are not mirrored either', async () => {
  const res = mockRes()
  await notifCtrl.putSubscriptions({ user: PLAYER, body: { streams: ['news.post', 'no.such.stream'] } }, res)
  assert.deepEqual(res.body, { streams: ['news.post'] })

  const surface = await prefs.getForUser(USER, PLAYER)
  assert.equal(item(surface, 'no.such.stream'), undefined)
  assert.deepEqual([...subRows], [`${USER} news.post`])
})

// ── Acceptance: defaults ───────────────────────────────────────────────────

test("a fresh user's modes are the channel defaults — push and email off, in-app on", async () => {
  const surface = await prefs.getForUser(USER, PLAYER)
  const news = item(surface, 'news.post')

  // **`inapp` is 'instant' from Phase 7**, and it is the only one that is.
  // Settled by the org lead 2026-08-31: the argument for opt-IN was that push
  // wakes a device somebody is holding and email leaves the building, and an
  // inbox item does neither — it is a row on a page the user chose to open. Left
  // 'off' the surface ships dead, because no rule could reach anybody until
  // every user found a toggle for a channel they had never seen deliver
  // anything.
  assert.deepEqual(news.modes, { push: 'off', email: 'off', inapp: 'instant' })
  assert.equal(prefRows.size, 0, 'reading preferences must not write rows')

  // The acceptance line in ENGAGEMENT.md originally said push defaults
  // 'instant'. It cannot: `notification_subscriptions` is opt-IN, so that would
  // have projected the whole catalog into the legacy GET for every existing
  // user and switched every toggle on in the shipped app. Settled 'off' by the
  // org lead; this assertion is what stops it drifting back.
  const legacy = mockRes()
  await notifCtrl.getSubscriptions({ user: PLAYER }, legacy)
  assert.deepEqual(legacy.body, { streams: [] })
})

test('a mode with no stored row reads as the channel default, not as a hardcoded off', async () => {
  // Prove the default is READ from the registry rather than assumed: re-register
  // `inapp` with a different default and the same fresh user reads it back.
  channels._reset()
  channels.registerDeliveryChannel({
    id: 'inapp', label: 'On the site', carriesContent: true, defaultMode: 'instant', supportsDigest: false,
  })

  const surface = await prefs.getForUser(USER, PLAYER)
  assert.equal(item(surface, 'news.post').modes.inapp, 'instant')
})

// ── Acceptance: the sparse per-channel PUT ─────────────────────────────────

test('a per-channel PUT sets email without touching push', async () => {
  await notifCtrl.putSubscriptions({ user: PLAYER, body: { streams: ['news.post'] } }, mockRes())

  const res = mockRes()
  await notifCtrl.putChannelPrefs(
    { user: PLAYER, body: { prefs: [{ id: 'news.post', channel: 'email', mode: 'digest' }] } },
    res,
  )

  const news = item(res.body, 'news.post')
  assert.equal(news.modes.email, 'digest')
  assert.equal(news.modes.push, 'instant', 'the push mode must survive an email-only write')

  // …and the legacy endpoint agrees, which is the whole point of the projection.
  const legacy = mockRes()
  await notifCtrl.getSubscriptions({ user: PLAYER }, legacy)
  assert.deepEqual(legacy.body, { streams: ['news.post'] })
})

test('a push write through the channels endpoint fans out to the old table', async () => {
  await notifCtrl.putChannelPrefs(
    { user: PLAYER, body: { prefs: [{ id: 'team.forum.post', channel: 'push', mode: 'instant' }] } },
    mockRes(),
  )
  assert.deepEqual([...subRows], [`${USER} team.forum.post`])

  await notifCtrl.putChannelPrefs(
    { user: PLAYER, body: { prefs: [{ id: 'team.forum.post', channel: 'push', mode: 'off' }] } },
    mockRes(),
  )
  assert.deepEqual([...subRows], [])

  // 'off' is STORED, not deleted: it is a statement the user made, and folding it
  // back into "never said" is only harmless while push's default happens to be
  // off. The two are different the moment that default changes.
  assert.equal(prefRows.get(`${USER} team.forum.post push`), 'off')
})

test('entries the catalog cannot accept are dropped, not refused', async () => {
  const res = mockRes()
  await notifCtrl.putChannelPrefs(
    {
      user: PLAYER,
      body: {
        prefs: [
          { id: 'no.such.id', channel: 'email', mode: 'instant' },
          { id: 'news.post', channel: 'carrier.pigeon', mode: 'instant' },
          { id: 'news.post', channel: 'push', mode: 'digest' }, // push has no digest
          { id: 'news.post', channel: 'email', mode: 'instant' }, // the one good row
        ],
      },
    },
    res,
  )

  assert.equal(res.statusCode, 200)
  assert.equal(item(res.body, 'news.post').modes.email, 'instant')
  assert.equal(item(res.body, 'news.post').modes.push, 'off')
  assert.equal(prefRows.size, 1, 'only the accepted pair was written')
})

test('the last entry wins when a body names the same pair twice', async () => {
  const res = mockRes()
  await notifCtrl.putChannelPrefs(
    {
      user: PLAYER,
      body: {
        prefs: [
          { id: 'news.post', channel: 'email', mode: 'instant' },
          { id: 'news.post', channel: 'email', mode: 'digest' },
        ],
      },
    },
    res,
  )
  assert.equal(item(res.body, 'news.post').modes.email, 'digest')
})

// ── The catalog: one namespace, two facets ─────────────────────────────────

test('a trigger-only id gets email and in-app, and no push toggle', async () => {
  const api = registries.stage('uo')
  api.registerEventTriggers([{
    id: 'uo.house.idoc_warning',
    label: 'House approaching collapse',
    ceiling: 'owner',
    variables: [{ name: 'house', type: 'string', required: true, example: 'The Silver Anvil' }],
  }])
  registries.apply(api.staged)

  const surface = await prefs.getForUser(USER, PLAYER)
  const idoc = item(surface, 'uo.house.idoc_warning')

  assert.ok(idoc, 'a trigger-only id is subscribable')
  assert.deepEqual(idoc.channels, ['email', 'inapp'])
  assert.equal('push' in idoc.modes, false, 'there is nothing registered to push it')

  // A push entry for it is therefore inapplicable and dropped.
  await notifCtrl.putChannelPrefs(
    { user: PLAYER, body: { prefs: [{ id: 'uo.house.idoc_warning', channel: 'push', mode: 'instant' }] } },
    mockRes(),
  )
  assert.equal(subRows.size, 0)
  assert.equal(prefRows.size, 0)
})

test('an id that is both a stream and a trigger appears once, with all three channels', async () => {
  // Core's five trigger ids ARE its five stream ids — the same-owner upgrade the
  // one-namespace rule exists for, exercised on every boot.
  const surface = await prefs.getForUser(USER, PLAYER)
  const news = surface.items.filter((i) => i.id === 'news.post')

  assert.equal(news.length, 1)
  assert.deepEqual(news[0].channels, ['push', 'email', 'inapp'])
  assert.equal(news[0].ceiling, 'authenticated', 'the trigger facet supplies the ceiling')
})

test('a staff-ceilinged trigger is not offered to a player, and is to staff', async () => {
  const api = registries.stage('uo')
  api.registerEventTriggers([{
    id: 'uo.cheat.detected',
    label: 'Cheat detected',
    ceiling: 'staff',
    variables: [{ name: 'character', type: 'string', required: true, example: 'Darrow' }],
  }])
  registries.apply(api.staged)

  const asPlayer = await prefs.getForUser(USER, PLAYER)
  assert.equal(item(asPlayer, 'uo.cheat.detected'), undefined, 'a player is not told it exists')

  const asAdmin = await prefs.getForUser(USER, ADMIN)
  assert.ok(item(asAdmin, 'uo.cheat.detected'))

  // And the filter is a gate, not just a display rule: a player who knows the id
  // still cannot store a preference for it.
  const res = mockRes()
  await notifCtrl.putChannelPrefs(
    { user: PLAYER, body: { prefs: [{ id: 'uo.cheat.detected', channel: 'email', mode: 'instant' }] } },
    res,
  )
  assert.equal(prefRows.size, 0)
})

// ── The channel registry itself ────────────────────────────────────────────

test('the registry refuses a channel that under-declares', async () => {
  channels._reset()
  const ok = { id: 'x', label: 'X', carriesContent: true, defaultMode: 'off', supportsDigest: false }

  assert.throws(() => channels.registerDeliveryChannel({ ...ok, carriesContent: undefined }), /carriesContent/)
  assert.throws(() => channels.registerDeliveryChannel({ ...ok, supportsDigest: undefined }), /supportsDigest/)
  assert.throws(() => channels.registerDeliveryChannel({ ...ok, defaultMode: 'sometimes' }), /defaultMode/)
  assert.throws(() => channels.registerDeliveryChannel({ ...ok, id: 'Not An Id' }), /invalid id/)

  // A channel that cannot batch cannot default to batching — the failure this
  // prevents is a stored 'digest' row no delivery path can ever honour.
  assert.throws(
    () => channels.registerDeliveryChannel({ ...ok, defaultMode: 'digest', supportsDigest: false }),
    /supportsDigest/,
  )

  channels.registerDeliveryChannel(ok)
  assert.throws(() => channels.registerDeliveryChannel(ok), /already registered/)
})

test('push is content-free and instant-only, by declaration', async () => {
  assert.equal(channels.get('push').carriesContent, false)
  assert.deepEqual(channels.modesFor('push'), ['off', 'instant'])
  assert.deepEqual(channels.modesFor('email'), ['off', 'instant', 'digest'])
})

test('an unregistered channel reads as off and accepts nothing', async () => {
  // A stored row can name a channel that is no longer registered (a downgrade).
  // It must read as off, never throw and never be on by accident.
  assert.equal(channels.defaultMode('discord.dm'), 'off')
  assert.deepEqual(channels.modesFor('discord.dm'), [])
  assert.equal(channels.acceptsMode('discord.dm', 'instant'), false)
})