const CommentModel = require('../models/CommentModel')
const UserModel = require('../models/UserModel')

const RATED_FILTER = { $ne: null, $gt: 0 }

const findExistingUserRating = (creatorId, targetUserId) => {
  return CommentModel.findOne({
    creator: creatorId,
    user: targetUserId,
    rating: RATED_FILTER,
  })
}

const hasCreatorRatedUser = async (creatorId, targetUserId) => {
  const existing = await findExistingUserRating(creatorId, targetUserId)
  return !!existing
}

const resolveRatingForComment = async ({ creatorId, targetUserId, rate }) => {
  const existingRating = await findExistingUserRating(creatorId, targetUserId)

  if (existingRating) {
    if (rate && rate >= 1 && rate <= 5) {
      return {
        ratingValue: null,
        isNewRating: false,
        alreadyRated: true,
      }
    }
    return { ratingValue: null, isNewRating: false }
  }

  if (!rate || rate < 1 || rate > 5) {
    return { ratingValue: null, isNewRating: false, requiresRating: false }
  }

  return { ratingValue: rate, isNewRating: true }
}

/** rate = مجموع ستاره‌های دریافتی | user_score = میانگین ۱ تا ۵ */
const getUserLevel = (user, totalStars) => {
  if (totalStars <= 500) return 'تازه وارد'
  if (totalStars <= 2000) return 'استاندارد'
  if (totalStars <= 10000) return 'حرفه‌ای'

  if (user.expertise === 'مدل') return 'سپورمدل'

  if (['زیبایی', 'عکاس', 'آرایشگر'].includes(user.expertise)) {
    return 'استاد'
  }

  return 'استاد'
}

const recalculateUserRating = async (targetUserId) => {
  const user = await UserModel.findById(targetUserId)
  if (!user) return

  const ratedComments = await CommentModel.find({
    user: targetUserId,
    rating: RATED_FILTER,
  }).sort({ createdAt: 1 })

  const uniqueRatingsByCreator = new Map()
  for (const comment of ratedComments) {
    const creatorKey = comment.creator.toString()
    if (!uniqueRatingsByCreator.has(creatorKey)) {
      uniqueRatingsByCreator.set(creatorKey, comment.rating)
    }
  }

  const ratings = Array.from(uniqueRatingsByCreator.values())
  const totalStars = ratings.reduce((acc, rating) => acc + rating, 0)
  const ratedCount = ratings.length

  user.rate = String(totalStars)
  user.user_score =
    ratedCount > 0 ? (totalStars / ratedCount).toFixed(1) : '0'
  user.user_level = getUserLevel(user, totalStars)
  await user.save()
}

module.exports = {
  RATED_FILTER,
  findExistingUserRating,
  hasCreatorRatedUser,
  resolveRatingForComment,
  recalculateUserRating,
  getUserLevel,
}