/**
 * @see https://github.com/surmon-china/nodepress/blob/main/src/processors/database/database.provider.ts
 */
import mongoose from 'mongoose'

import { MONGO_DB } from '~/app.config'

let databaseConnection: mongoose.Connection | null = null
export const getDatabaseConnection = async () => {
  if (databaseConnection) {
    return databaseConnection
  }
  let reconnectionTask: NodeJS.Timeout | null = null
  const RECONNECT_INTERVAL = 6000

  const connection = () => {
    return mongoose.connect(MONGO_DB.uri, {})
  }
  const Badge = `[${chalk.yellow('MongoDB')}]`

  const color = (str: TemplateStringsArray) => {
    return str.map((s) => chalk.green(s)).join('')
  }
  mongoose.connection.on('connecting', () => {
    consola.info(Badge, color`connecting...`)
  })

  mongoose.connection.on('open', () => {
    consola.info(Badge, color`readied!`)
    if (reconnectionTask) {
      clearTimeout(reconnectionTask)
      reconnectionTask = null
    }
  })

  mongoose.connection.on('disconnected', () => {
    consola.error(
      Badge,
      chalk.red(`disconnected! retry when after ${RECONNECT_INTERVAL / 1000}s`),
    )
    reconnectionTask = setTimeout(connection, RECONNECT_INTERVAL)
  })

  mongoose.connection.on('error', (error) => {
    consola.error(Badge, 'error!', error)
    mongoose.disconnect()
  })

  databaseConnection = await connection().then(
    (mongoose) => mongoose.connection,
  )

  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
  return databaseConnection!
}