// ── The voice the module's own lines are said in (phase 17, D140) ──────────
//
// One fleet setting (§33.4 reading 5): the name of a permission group that has
// a BetterChat style, or nothing for plain chat. News lines and `rust.announce`
// lines are then said in that group's title and colours — composed here, said by
// our plugin with no player as the sender, so they look right whether or not
// BetterChat is loaded.
//
// The style is read at the moment a line is said, never copied into the
// setting: an operator who recolours the group changes the voice with it, and a
// group whose style is taken away stops being a voice rather than leaving a
// stale one behind.

const settingsDb = require('../visibility/visibility.db')
const chatStyle = require('./chatStyle')
const db = require('./permissions.db')
const model = require('./permissions.model')

const VOICE_KEY = 'announce.voice'

/** The chosen group's name, or '' for plain chat. */
async function chosen() {
  return (await settingsDb.getSetting(VOICE_KEY)) || ''
}

/**
 * The format a line is said in right now, or null for plain chat — which is
 * also the answer when the chosen group has since lost its style or gone.
 */
async function currentFormat() {
  const group = await chosen()
  if (!group) return null

  const fields = await db.getGroupChat(group)
  return fields ? chatStyle.voiceFormat(fields) : null
}

/** The setting, and every group that could be a voice, for the admin page. */
async function describe() {
  const [voice, rows] = await Promise.all([chosen(), db.listGroupChat()])
  const options = []

  for (const [group, fields] of model.chatByGroup(rows)) {
    const format = chatStyle.voiceFormat(fields)
    if (format) options.push({ group, title: fields.Title || group, format })
  }

  return { voice, options: options.sort((a, b) => a.group.localeCompare(b.group)) }
}

/**
 * Choose the voice. A group is accepted only when it has a style a voice can be
 * made from; '' goes back to plain chat. Resolves `{ ok }` or
 * `{ ok: false, message }`.
 */
async function choose(group, userId = null) {
  const name = model.normaliseName(group)

  if (name) {
    const fields = await db.getGroupChat(name)
    if (!fields || !chatStyle.voiceFormat(fields)) {
      return { ok: false, message: `The group "${name}" has no chat style, so it cannot be a voice. Give it one under Permissions first.` }
    }
  }

  await settingsDb.setSetting(VOICE_KEY, name, userId)
  return { ok: true, voice: name }
}

module.exports = { VOICE_KEY, chosen, currentFormat, describe, choose }