// ── The in-game town-crier announce leg ────────────────────────────────────
//
// MODULE-UO CONTENT, still living in core. MODULE_SYSTEM.md §1.8's third
// entangled file: utils/announceWorker.js is core's news dispatcher, but one of
// its two delivery legs goes to the shard through uoLinkClient.postTownCrier.
// PR 4 turned the legs into registrations, and this file is what module-uo will
// register in Phase 3 — it moves whole, with `'core'` becoming `'uo'` and the
// leg id staying `towncrier` (grandfathered in registries.js: the id is a stored
// value in announce_job_legs.leg).

const uoLinkClient = require('./uoLinkClient')
const { deriveExcerpt } = require('./excerpt')
const { articleUrl, baseUrl, legError } = require('./announceLinks')

const TOWNCRIER_DURATION_SEC = Number(process.env.TOWNCRIER_DURATION_SEC) || 3600

// Sidecar town-crier caps, mirrored from the admin route validation
// (admin/uoLink.router.js: lines isArray({ max: 8 }), lines.* isLength({ max: 200 })).
// We pre-truncate to these so a published post never bounces with an error.
const MAX_LINES = 8
const MAX_LINE_LEN = 200

// Trim to a hard length, appending an ellipsis only when something was cut.
function clamp(value, max) {
  const s = String(value == null ? '' : value)
    .replace(/\s+/g, ' ')
    .trim()
  if (s.length <= max) return s
  return `${s.slice(0, max - 1).trimEnd()}…`
}

// Build the town-crier lines: title, a one-line excerpt, then the URL. Each line
// is clamped to the sidecar's per-line cap and the whole thing to the line-count
// cap. Falls back to a stripped body excerpt when the post has no excerpt.
function buildTownCrierText(post, { baseUrl: base } = {}) {
  const title = clamp(post.title, MAX_LINE_LEN)
  const excerptSource = post.excerpt || deriveExcerpt(post.body, MAX_LINE_LEN) || ''
  const lines = [title]
  const excerpt = clamp(excerptSource, MAX_LINE_LEN)
  if (excerpt) lines.push(excerpt)
  const url = clamp(articleUrl(base), MAX_LINE_LEN)
  if (url) lines.push(url)
  return lines.filter(Boolean).slice(0, MAX_LINES)
}

async function dispatch(post) {
  const lines = buildTownCrierText(post, { baseUrl: baseUrl() })
  // Stable id: re-posting `post-<id>` REPLACES the prior town-crier entry rather
  // than stacking a duplicate, so a retry after a partial failure is safe.
  return uoLinkClient.postTownCrier({
    id: `post-${post.id}`,
    lines,
    durationSec: TOWNCRIER_DURATION_SEC,
  })
}

function classify(result) {
  if (result && result.ok) return { outcome: 'done' }
  const status = result ? result.status : 0
  // 400 = over the line/duration caps (a data problem — do NOT retry).
  // 401 = token mismatch, 409 = protocol mismatch (both config problems).
  if (status === 400 || status === 401 || status === 409) {
    return { outcome: 'terminal', error: legError(result) }
  }
  // 503 (shard not connected), 504 (shard timeout), 0 (network/timeout / not
  // configured yet), and any other 5xx are transient — retry.
  return { outcome: 'retry', error: legError(result) }
}

const leg = {
  leg: 'towncrier',
  label: 'In-game town crier',
  dispatch,
  classify,
}

module.exports = { leg, dispatch, classify, buildTownCrierText, MAX_LINES, MAX_LINE_LEN }