// ── The operator's voice controls ──────────────────────────────────────────
//
// TEAMS.md §7.3, phase 9. Five `settings` keys, in their own file for the reason
// `teamForumSettings` is: two of them are not ordinary keys. `teams_voice_enabled`
// has a server-side precondition (the bot must actually be able to manage channels
// and roles — §7.3 assumed it could and the tree has never checked), and
// `teams_voice_category_ref` is written by the SERVER after the bot reports what
// it created, not by the admin who is looking at the form.
//
//   teams_voice_enabled       '0' | '1'          default '0' — off
//   teams_voice_min_members   1 … 10000          default 5
//   teams_voice_grace_days    0 … 90             default 7
//   teams_voice_category_ref  a channel id       absent until the bot makes one
//   teams_voice_staff_roles   CSV of role ids    empty by default
//
// **Every read fails closed**, the same bargain the forum settings take: a DB
// fault reports voice off, which costs a pass that does nothing and is repeated
// fifteen minutes later. Failing open would mean creating guild structure on the
// strength of a query that did not answer.
//
// **`teams_voice_staff_roles` exists because "the staff role" does not.** §7.3
// grants the staff role an overwrite on every Team channel; this codebase has no
// staff-role concept at all — `guild_config` knows a news channel, a modlog
// channel, an autorole and a filter allowlist, and none of them means "staff".
// Guild administrators bypass channel overwrites anyway, so what is actually
// missing is a way to let NON-admin staff in, and only the operator can say which
// of their Discord roles those are. Empty is a legitimate and common answer.

const settingsDb = require('../settings/settings.db')

const ENABLED_KEY = 'teams_voice_enabled'
const MIN_MEMBERS_KEY = 'teams_voice_min_members'
const GRACE_DAYS_KEY = 'teams_voice_grace_days'
const CATEGORY_KEY = 'teams_voice_category_ref'
const STAFF_ROLES_KEY = 'teams_voice_staff_roles'

const MIN_MEMBERS_DEFAULT = 5
const MIN_MEMBERS_MAX = 10000

const GRACE_DAYS_DEFAULT = 7
const GRACE_DAYS_MAX = 90

// Discord's guild-wide role cap. It is the ceiling on how many Teams can have
// voice at all, and it is here rather than in the bot because the admin panel has
// to be able to say "you are at 231 of 250" BEFORE a create fails — §7.3's error
// state per Team is a diagnosis, not a warning.
//
// The number is Discord's and core cannot read it; a guild that gets a different
// one is a guild where this warns early, which is the harmless direction.
const ROLE_CAP = 250

// The same shape `teamIntegration.model` validates a channel with. Core treats
// every Discord id as opaque and only checks it could be one.
const SNOWFLAKE_RE = /^[0-9]{5,32}$/

/** Is voice provisioning switched on? Fail closed. */
async function enabled() {
  try {
    return String(await settingsDb.get(ENABLED_KEY)) === '1'
  } catch {
    return false
  }
}

/**
 * The membership threshold, counting every active member (org lead, 2026-08-18).
 *
 * Fails closed to the DEFAULT rather than to zero, unlike the forum's edit window:
 * zero here would mean "provision every Team including the one-person ones", which
 * is the expensive direction against a 250-role cap. The default is the
 * conservative answer, not the permissive one.
 */
async function minMembers() {
  try {
    const raw = await settingsDb.get(MIN_MEMBERS_KEY)
    if (raw == null || raw === '') return MIN_MEMBERS_DEFAULT
    const n = Number(raw)
    if (!Number.isFinite(n) || n < 1 || n > MIN_MEMBERS_MAX) return MIN_MEMBERS_DEFAULT
    return Math.floor(n)
  } catch {
    return MIN_MEMBERS_DEFAULT
  }
}

/**
 * How long a Team keeps its channel after it stops qualifying (§7.3).
 *
 * `0` is legitimate and means "remove on the next pass" — an operator who would
 * rather not have stale channels lying about. A DB fault reports the default, so a
 * transient error can never turn the window off and delete something early; the
 * grace window's whole job is to not act in a hurry.
 */
async function graceDays() {
  try {
    const raw = await settingsDb.get(GRACE_DAYS_KEY)
    if (raw == null || raw === '') return GRACE_DAYS_DEFAULT
    const n = Number(raw)
    if (!Number.isFinite(n) || n < 0 || n > GRACE_DAYS_MAX) return GRACE_DAYS_DEFAULT
    return Math.floor(n)
  } catch {
    return GRACE_DAYS_DEFAULT
  }
}

/**
 * The parent category every Team channel is created under, or null.
 *
 * Not an admin field. The bot creates the category on the first pass that needs
 * one and reports the id back; the server stores it here so the next pass reuses
 * it instead of making a second. An operator who wants a different category
 * deletes this value (or the category) and the next pass makes a fresh one — which
 * is why it is exposed read-only in the panel with a clear button rather than as a
 * text input somebody could point at a channel that is not a category.
 */
async function categoryRef() {
  try {
    const value = await settingsDb.get(CATEGORY_KEY)
    const text = String(value || '').trim()
    return SNOWFLAKE_RE.test(text) ? text : null
  } catch {
    return null
  }
}

async function setCategoryRef(value, actorId = null) {
  const text = String(value || '').trim()
  if (text && !SNOWFLAKE_RE.test(text)) throw new Error('category ref must be a numeric channel id')
  return settingsDb.set(CATEGORY_KEY, text || null, actorId)
}

/**
 * The roles that see every Team voice channel, in addition to that Team's own.
 *
 * Stored as CSV for the same reason `filter_allow_roles` is — `settings.value` is
 * a VARCHAR and a JSON array in it buys nothing when the elements are numeric ids.
 * Unreadable entries are DROPPED rather than rejected on read: a hand-edited row
 * with one bad id should cost that id, not every staff grant on the deployment.
 */
async function staffRoles() {
  try {
    const raw = await settingsDb.get(STAFF_ROLES_KEY)
    return parseRoles(raw)
  } catch {
    return []
  }
}

function parseRoles(raw) {
  return String(raw || '')
    .split(',')
    .map((part) => part.trim())
    .filter((part) => SNOWFLAKE_RE.test(part))
}

/**
 * Validate an operator-supplied staff-role list on the way IN, where a typo can
 * still be reported to the person who made it.
 *
 * Rejected rather than filtered, the same call the bridge's event list makes: a
 * silently-dropped id is a settings screen that shows you saved something you did
 * not, and a role that was supposed to see every Team channel and does not is a
 * failure nobody would think to look for.
 */
function normaliseStaffRoles(input) {
  const parts = Array.isArray(input)
    ? input
    : String(input == null ? '' : input).split(',')
  const seen = []
  for (const part of parts) {
    const id = String(part || '').trim()
    if (!id) continue
    if (!SNOWFLAKE_RE.test(id)) {
      const err = new Error(`not a role id: ${id}`)
      err.status = 400
      throw err
    }
    if (!seen.includes(id)) seen.push(id)
  }
  return seen
}

/** Everything the reconciler and the admin panel both need, in one read. */
async function all() {
  const [on, min, grace, category, staff] = await Promise.all([
    enabled(), minMembers(), graceDays(), categoryRef(), staffRoles(),
  ])
  return {
    enabled: on,
    minMembers: min,
    graceDays: grace,
    categoryRef: category,
    staffRoles: staff,
    roleCap: ROLE_CAP,
  }
}

/**
 * Persist an admin's save. Returns the settings as they now read, so the panel
 * renders what was stored rather than what was typed.
 *
 * The enable PRECONDITION is not here: it needs the bot, and a settings module
 * that reached across to another process to validate a write would be impossible
 * to test and surprising to read. The controller asks the bot and refuses, in the
 * same shape §7.2's acknowledgement refuses — 422 before the write, never a quiet
 * failure after it.
 */
async function save({ enabled: on, minMembers: min, graceDays: grace, staffRoles: staff }, actorId = null) {
  const next = {}
  if (on !== undefined) next[ENABLED_KEY] = on ? '1' : '0'
  if (min !== undefined) {
    const n = Number(min)
    if (!Number.isInteger(n) || n < 1 || n > MIN_MEMBERS_MAX) {
      const err = new Error(`minimum members must be between 1 and ${MIN_MEMBERS_MAX}`)
      err.status = 400
      throw err
    }
    next[MIN_MEMBERS_KEY] = String(n)
  }
  if (grace !== undefined) {
    const n = Number(grace)
    if (!Number.isInteger(n) || n < 0 || n > GRACE_DAYS_MAX) {
      const err = new Error(`the grace window must be between 0 and ${GRACE_DAYS_MAX} days`)
      err.status = 400
      throw err
    }
    next[GRACE_DAYS_KEY] = String(n)
  }
  if (staff !== undefined) next[STAFF_ROLES_KEY] = normaliseStaffRoles(staff).join(',')

  for (const [key, value] of Object.entries(next)) {
    // eslint-disable-next-line no-await-in-loop
    await settingsDb.set(key, value, actorId)
  }
  return all()
}

module.exports = {
  ENABLED_KEY,
  MIN_MEMBERS_KEY,
  GRACE_DAYS_KEY,
  CATEGORY_KEY,
  STAFF_ROLES_KEY,
  MIN_MEMBERS_DEFAULT,
  GRACE_DAYS_DEFAULT,
  ROLE_CAP,
  enabled,
  minMembers,
  graceDays,
  categoryRef,
  setCategoryRef,
  staffRoles,
  parseRoles,
  normaliseStaffRoles,
  all,
  save,
}