import type { RegisterServerOptions } from '@peertube/peertube-types'
import { migrateSettings } from './lib/migration/settings'
import { initSettings } from './lib/settings'
import { initCustomFields } from './lib/custom-fields'
import { initRouters } from './lib/routers/index'
import { initFederation } from './lib/federation/init'
import { initChannelConfiguration } from './lib/configuration/channel/init'
import { initRSS } from './lib/rss/init'
import { prepareProsody, ensureProsodyRunning, ensureProsodyNotRunning } from './lib/prosody/ctl'
import { unloadDebugMode } from './lib/debug'
import { loadLoc } from './lib/loc'
import { RoomChannel } from './lib/room-channel'
import { BotConfiguration } from './lib/configuration/bot'
import { BotsCtl } from './lib/bots/ctl'
import decache from 'decache'

// FIXME: Peertube unregister don't have any parameter.
// Using this global variable to fix this, so we can use helpers to unregister.
let OPTIONS: RegisterServerOptions | undefined

async function register (options: RegisterServerOptions): Promise<any> {
  OPTIONS = options
  const logger = options.peertubeHelpers.logger

  // This is a trick to check that peertube is at least in version 3.2.0
  if (!options.peertubeHelpers.plugin) {
    throw new Error('Your peertube version is not correct. This plugin is not compatible with Peertube < 3.2.0.')
  }

  // First: load languages files, so we can localize strings.
  await loadLoc()
  // Then load the BotConfiguration singleton
  await BotConfiguration.initSingleton(options)
  // Then load the RoomChannel singleton
  const roomChannelSingleton = await RoomChannel.initSingleton(options)
  // roomChannelNeedsDataInit: if true, means that the data file does not exist (or is invalid), so we must initiate it
  const roomChannelNeedsDataInit = !await roomChannelSingleton.readData()

  // BotsCtl.initSingleton() will force reload the bots conf files, so must be done before generating Prosody Conf.
  await BotsCtl.initSingleton(options)

  await migrateSettings(options)

  await initSettings(options)
  await initCustomFields(options)
  await initRouters(options)
  await initFederation(options)
  await initChannelConfiguration(options)
  await initRSS(options)

  try {
    await prepareProsody(options)
    await ensureProsodyRunning(options)

    let preBotPromise: Promise<void>
    if (roomChannelNeedsDataInit) {
      logger.info('The RoomChannel singleton has not found any data, we must rebuild')
      // no need to wait here, can be done without await.
      preBotPromise = roomChannelSingleton.rebuildData().then(
        () => { logger.info('RoomChannel singleton rebuild done') },
        (reason) => { logger.error('RoomChannel singleton rebuild failed: ' + (reason as string)) }
      )
    } else {
      preBotPromise = Promise.resolve()
    }

    // Don't need to wait for the bot to start.
    preBotPromise.then(
      async () => {
        await BotsCtl.singleton().start()
      },
      () => {}
    )
  } catch (error) {
    options.peertubeHelpers.logger.error('Error when launching Prosody: ' + (error as string))
  }
}

async function unregister (): Promise<any> {
  try {
    await BotsCtl.destroySingleton()
  } catch (_error) {} // BotsCtl will log errors.

  if (OPTIONS) {
    try {
      await ensureProsodyNotRunning(OPTIONS)
    } catch (error) {
      OPTIONS.peertubeHelpers.logger.error('Error when trying to unload Prosody: ' + (error as string))
    }
  }

  unloadDebugMode()

  await RoomChannel.destroySingleton()
  await BotConfiguration.destroySingleton()

  const module = __filename
  OPTIONS?.peertubeHelpers.logger.info(`Unloading module ${module}...`)
  // Peertube calls decache(plugin) on register, not unregister.
  // Will do here, to release memory.
  decache(module)
  OPTIONS?.peertubeHelpers.logger.info(`Successfully unloaded the module ${module}`)
  OPTIONS = undefined
}

module.exports = {
  register,
  unregister
}