// Which cliloc source runs, and what the shard path does with the answer
// (docs/link/v8.md §9, docs/website/CLILOCS.md).
//
// The model is the only place that decides between the two pipelines, so these
// drive it with the shard, the database and the filesystem all stubbed. Nothing
// here reaches the real sidecar or a real table.

const { test } = require('node:test')
const assert = require('node:assert/strict')
const fs = require('node:fs')
const os = require('node:os')
const path = require('node:path')

const clilocs = require('../model/shardClilocs/shardClilocs.model')
const db = require('../model/shardClilocs/shardClilocs.db')
const bridge = require('../utils/clilocBridge')
const uoLinkConfig = require('../model/uoLinkConfig/uoLinkConfig.model')
const { ctx } = require('./_setup')

const saved = {
  getMeta: db.getMeta,
  replaceAll: db.replaceAll,
  count: db.count,
  fingerprint: bridge.fingerprint,
  readCliloc: bridge.readCliloc,
  getSafe: uoLinkConfig.getSafe,
  settingsGet: ctx.settings.get,
}

function restore() {
  db.getMeta = saved.getMeta
  db.replaceAll = saved.replaceAll
  db.count = saved.count
  bridge.fingerprint = saved.fingerprint
  bridge.readCliloc = saved.readCliloc
  uoLinkConfig.getSafe = saved.getSafe
  ctx.settings.get = saved.settingsGet
}

const FINGERPRINT = {
  kind: 'bridge',
  file: 'cliloc.enu',
  size: 4989921,
  mtime: 1757462400000,
  sha256: 'abc',
  extractorVersion: 1,
  hashing: false,
  complete: true,
}

/**
 * A rig with the shard reachable (or not), the configured overlay path pointed
 * at a temp directory, and every write captured rather than made.
 */
function rig({ linked = true, meta = null, clientPath = '', rows = [] } = {}) {
  const applied = []

  uoLinkConfig.getSafe = async () => ({ enabled: linked, baseUrl: linked ? 'http://127.0.0.1:8099' : null })
  ctx.settings.get = async (key) => (key === clilocs.SETTING_KEY ? clientPath : null)

  db.getMeta = async () => meta
  db.count = async () => meta?.count ?? 0
  db.replaceAll = async (entries, writtenMeta) => {
    applied.push({ entries, meta: writtenMeta })
    return { count: entries.length, blank: 0, duplicates: 0 }
  }

  bridge.fingerprint = async () => FINGERPRINT
  bridge.readCliloc = async () => ({
    entries: rows,
    source: {
      kind: 'bridge',
      lang: 'enu',
      file: 'cliloc.enu',
      size: FINGERPRINT.size,
      mtime: FINGERPRINT.mtime,
      pages: 1,
      reported: rows.length,
      received: rows.length,
    },
  })

  return applied
}

function tmpWithOverlay(contents) {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'cliloc-sel-'))
  fs.mkdirSync(path.join(dir, 'custom'), { recursive: true })
  if (contents !== undefined) fs.writeFileSync(path.join(dir, 'custom', 'shard.tsv'), contents)
  return dir
}

// ── Which source runs ──────────────────────────────────────────────────────

test('a configured shard is the base source, and the file path is not consulted', async (t) => {
  const applied = rig({ rows: [{ number: 1, flag: 0, text: 'a' }] })
  t.after(restore)

  const result = await clilocs.refresh()

  assert.equal(result.status, 'imported')
  assert.equal(result.source, 'bridge')
  assert.equal(applied.length, 1)
  assert.equal(applied[0].meta.source, 'bridge')
})

test('no shard link falls back to the file pipeline, unchanged', async (t) => {
  rig({ linked: false })
  t.after(restore)

  // No path configured either, so the file path reports exactly what it always
  // did — which is the assertion: the fallback is the OLD code, not a new one.
  const result = await clilocs.refresh()

  assert.equal(result.status, 'skipped')
  assert.equal(result.reason, 'no cliloc path configured')
})

test('an explicit path is still an escape hatch, even with a shard linked', async (t) => {
  let asked = false
  rig({ linked: true })
  bridge.fingerprint = async () => {
    asked = true
    return FINGERPRINT
  }
  t.after(restore)

  const result = await clilocs.refresh({ path: path.join(os.tmpdir(), 'nope-does-not-exist') })

  assert.equal(asked, false, 'the shard must not be asked when a file was named')
  assert.equal(result.status, 'unavailable')
})

// Boot deliberately does not call the shard: it would put a sidecar round trip
// in the startup sequence to answer a question whose answer is "no" except after
// a client patch, which is an operator action.
test('boot imports nothing over the bridge and leaves the loaded table serving', async (t) => {
  let asked = false
  rig({ linked: true })
  bridge.fingerprint = async () => {
    asked = true
    return FINGERPRINT
  }
  t.after(restore)

  const result = await clilocs.refreshOnBoot()

  assert.equal(result.status, 'skipped')
  assert.equal(result.source, 'bridge')
  assert.equal(asked, false)
})

// ── The gate ───────────────────────────────────────────────────────────────

test('an unchanged client file and no overlays is a no-op', async (t) => {
  const applied = rig({
    meta: { source: 'bridge', base: FINGERPRINT, hashes: {}, parserVersion: 1, count: 67496 },
  })
  t.after(restore)

  const result = await clilocs.refresh()

  assert.equal(result.status, 'unchanged')
  assert.equal(result.count, 67496)
  assert.equal(applied.length, 0)
})

test('a patched client re-imports', async (t) => {
  const applied = rig({
    meta: {
      source: 'bridge',
      base: { ...FINGERPRINT, sha256: 'older' },
      hashes: {},
      parserVersion: 1,
      count: 10,
    },
    rows: [{ number: 1, flag: 0, text: 'a' }],
  })
  t.after(restore)

  assert.equal((await clilocs.refresh()).status, 'imported')
  assert.equal(applied.length, 1)
})

// The upgrade path. An install that used the converted-file pipeline carries its
// base label in the stored fingerprint; on the bridge that label is SUPPOSED to
// disappear. Counting it as a vanished source would make the first import after
// the upgrade demand an approval for a change the upgrade itself made.
test('the retired file base is not reported as a vanished source', async (t) => {
  const applied = rig({
    meta: {
      source: 'file',
      hashes: { 'clilocs.plain': 'aaa' },
      parserVersion: 1,
      count: 67496,
    },
    rows: [{ number: 1, flag: 0, text: 'a' }],
  })
  t.after(restore)

  const result = await clilocs.refresh()

  assert.equal(result.status, 'imported', result.reason)
  assert.equal(applied.length, 1)
})

// An overlay is a different matter: it vanished, and an unmounted volume looks
// exactly like a deliberate deletion from here.
test('a vanished OVERLAY still stages for review', async (t) => {
  const applied = rig({
    meta: {
      source: 'bridge',
      base: FINGERPRINT,
      hashes: { 'custom/shard.tsv': 'aaa' },
      parserVersion: 1,
      count: 5,
    },
  })
  t.after(restore)

  const result = await clilocs.refresh()

  assert.equal(result.status, 'needsReview')
  assert.deepEqual(result.missingSources, ['custom/shard.tsv'])
  assert.equal(applied.length, 0)

  const accepted = await clilocs.refresh({ approve: true })
  assert.equal(accepted.status, 'imported')
  assert.deepEqual(accepted.acceptedMissing, ['custom/shard.tsv'])
})

// ── The merge ──────────────────────────────────────────────────────────────

test('an overlay overrides the shard table, and says so', async (t) => {
  const dir = tmpWithOverlay('1023721\ta better staff\n900001\ta shard-only item\n')
  const applied = rig({
    clientPath: dir,
    rows: [
      { number: 1023721, flag: 0, text: 'quarter staff' },
      { number: 3000001, flag: 0, text: 'Entering Britannia...' },
    ],
  })
  t.after(() => {
    restore()
    fs.rmSync(dir, { recursive: true, force: true })
  })

  const result = await clilocs.refresh()

  assert.equal(result.status, 'imported', result.reason)

  const stored = new Map(applied[0].entries.map((e) => [e.number, e.text]))
  assert.equal(stored.get(1023721), 'a better staff', 'the overlay must win')
  assert.equal(stored.get(3000001), 'Entering Britannia...')
  assert.equal(stored.get(900001), 'a shard-only item')

  const overlay = result.sources.find((s) => s.kind === 'custom')
  assert.equal(overlay.label, 'custom/shard.tsv')
  assert.equal(overlay.added, 1)
  assert.equal(overlay.overrode, 1)

  // Only overlay hashes are stored now — the base is fingerprinted separately,
  // and mixing them is what made the upgrade case above ambiguous.
  assert.deepEqual(Object.keys(applied[0].meta.hashes), ['custom/shard.tsv'])
  assert.equal(applied[0].meta.base.sha256, 'abc')
})

test('a malformed overlay names the file rather than failing the import namelessly', async (t) => {
  const dir = tmpWithOverlay('not a cliloc file at all\n')
  rig({ clientPath: dir, rows: [{ number: 1, flag: 0, text: 'a' }] })
  t.after(() => {
    restore()
    fs.rmSync(dir, { recursive: true, force: true })
  })

  const result = await clilocs.refresh()

  assert.equal(result.status, 'unavailable')
  assert.match(result.reason, /custom\/shard\.tsv/)
})

// An overlay path an operator has mistyped must not stop a base table that
// arrived perfectly well — but it must be visible, or the site silently serves a
// table missing every shard-added name.
test('an unreadable overlay path is reported beside a successful import', async (t) => {
  const applied = rig({
    clientPath: path.join(os.tmpdir(), 'cliloc-does-not-exist-at-all'),
    rows: [{ number: 1, flag: 0, text: 'a' }],
  })
  t.after(restore)

  const result = await clilocs.refresh()

  assert.equal(result.status, 'imported')
  assert.match(result.overlayProblem, /does not exist/)
  assert.equal(applied.length, 1)
})

// ── Status ─────────────────────────────────────────────────────────────────

test('status describes the shard source, hash state and drift', async (t) => {
  rig({ meta: { source: 'bridge', base: FINGERPRINT, hashes: {}, parserVersion: 1, count: 67496 } })
  t.after(restore)

  const status = await clilocs.status()

  assert.equal(status.source, 'bridge')
  assert.equal(status.file, 'cliloc.enu')
  assert.equal(status.fileReadable, true)
  assert.equal(status.drift, false)
  assert.equal(status.shard.extractorVersion, 1)
  assert.equal(status.shard.hashing, false)
})

test('a shard that cannot be reached is a problem on the status, not a throw', async (t) => {
  rig({})
  bridge.fingerprint = async () => {
    throw new bridge.ClilocBridgeError('The shard did not answer: timeout', 'SHARD_DOWN')
  }
  t.after(restore)

  const status = await clilocs.status()

  assert.equal(status.source, 'bridge')
  assert.equal(status.fileReadable, false)
  assert.equal(status.code, 'SHARD_DOWN')
  // Null, not false: with no fingerprint there is nothing to compare, and
  // reporting "no drift" would read as "up to date".
  assert.equal(status.drift, null)
})