const admin = require('firebase-admin')
const { FieldValue } = require('firebase-admin/firestore')
const { onDocumentDeleted, onDocumentCreated } = require('firebase-functions/firestore')
const { refList } = require('../index')
const { ORDER_TYPES, createOrderDocument } = require('./helpers/orders')
const { deleteFolder } = require('../helpers/firebase')
const { Resend } = require('resend')
const { welcomeTemplate } = require('../helpers/email')
const { RESEND_API_KEY } = require('../config/secrets')
const { onRequest } = require('firebase-functions/https')

let resendClient = null

const getResendClient = () => {
  if (!resendClient) {
    resendClient = new Resend(RESEND_API_KEY.value())
  }
  return resendClient
}

const WELCOME_EMAIL_FROM = 'MusicLand <musicland@musicland.ai>'
const WELCOME_EMAIL_SUBJECT = 'Bienvenue sur MusicLand'
const USER_CREATED_OPTIONS = {
  document: 'users/{userID}',
  secrets: [RESEND_API_KEY],
}

exports.testWelcomMail = onRequest({ secrets: [RESEND_API_KEY] }, async (req, res) => {
  if (req.method !== 'GET') {
    res.set('Allow', 'GET')
    return res.status(405).json({ success: false, error: 'Method not allowed' })
  }
  try {
    const targetEmail = req.query.email || 'tdtomthomas@gmail.com'
    const firstName = req.query.firstName || 'Toto'
    const lastName = req.query.lastName || 'Test'
    const { data, error } = await getResendClient().emails.send({
      from: WELCOME_EMAIL_FROM,
      to: [targetEmail],
      subject: WELCOME_EMAIL_SUBJECT,
      html: welcomeTemplate({ firstName, lastName }),
    })
    if (error) {
      console.log('Failed to send welcome email:', error)
      return res.status(500).json({ success: false, error: error.message || error.toString() })
    }
    console.log('Welcome email sent:', data)
    return res.status(200).json({ success: true, data })
  } catch (e) {
    console.log(e)
    return res.status(500).json({ success: false, error: e.message || e.toString() })
  }
})

exports.onUserCreated = onDocumentCreated(USER_CREATED_OPTIONS, async (event) => {
  try {
    const { email = '', firstName = '', lastName = '' } = event?.data?.data() || {}

    const userId = event?.params?.userID

    try {
      await createOrderDocument({
        userId,
        type: ORDER_TYPES.GIFT,
        amount: 10,
        metadata: { reason: 'WELCOME_BONUS' },
        orderId: `welcome_${userId}`,
      })
    } catch (coinError) {
      console.warn(
        '[users-onUserCreated] Unable to grant welcome coins',
        event?.params?.userID,
        coinError?.message || coinError
      )
    }
    if (email) {
      try {
        console.log(`Sending welcome email to ${email}`)
        const { data, error } = await getResendClient().emails.send({
          from: WELCOME_EMAIL_FROM,
          to: [email],
          subject: WELCOME_EMAIL_SUBJECT,
          html: welcomeTemplate({ firstName, lastName }),
        })
        if (error) {
          console.log('Failed to send welcome email:', error)
          return
        }
        console.log('Welcome email sent:', data)
      } catch (error) {
        console.log('Failed to send welcome email:', error)
      }
    } else {
      throw new Error('User created with empty email')
    }
  } catch (e) {
    console.log(e)
  }
})

exports.onUserDelete = onDocumentDeleted('users/{userID}', async (event) => {
  try {
    const userID = event?.params?.userID
    await clearAllUserData(userID)

    await deleteFolder(`users/${userID}/`)

    await admin.auth().deleteUser(userID)
    console.log(`User ${userID} deleted successfully`)
  } catch (e) {
    console.log(e)
  }
})

async function clearAllUserData(userID) {
  const deleteAll = async (ref, key, operator = '==') => {
    const snapshot = await ref.where(key, operator, userID).get()
    snapshot.forEach((item) => item.ref.delete())
  }
  const removeFromArray = async (ref, arrayName) => {
    const snapshot = await ref.where(arrayName, 'array-contains', userID).get()
    snapshot.forEach((item) =>
      item.ref.update({
        [arrayName]: FieldValue.arrayRemove(userID),
      })
    )
  }

  await deleteAll(refList.projects, 'userId')
  await deleteAll(refList.playlists, 'createdBy')
}