'use client'

import { useCallback, useEffect, useState } from 'react'

import { coerceToString } from '@/helpers'
import { addToast } from '@/lib/toast'
import Button from '@/components/formElements/Button'
import Input from '@/components/formElements/Input'
import AdminState from '@/components/feedback/AdminState'
import ConsumerState from '@/components/feedback/ConsumerState'
import ConsumerModal from '@/components/consumer/ConsumerModal'
import ReviewCard from '@/components/reviews/ReviewCard'
import StatusChip from '@/components/ui/StatusChip'
import { getReviewStatus } from '@/constants/status'
import { isWithinHostReplyWindow } from '@/lib/reviewWindow'
import {
  EVENT_REVIEWS_PAGE_SIZE,
  HOST_REPLY_REVIEW,
  LIST_ADMIN_EVENT_REVIEWS_PAGE,
  LIST_EVENT_REVIEWS_PAGE,
  type EventReview,
} from '@/services/reviews'
import { texts } from '@/texts'

interface EventReviewsPanelProps {
  eventId: string
  /**
   * Scheduled event end — host reply window is endsAt + 2 months.
   * Required for host mode; unused when mode is admin (read-only).
   */
  endsAt?: string
  /** Host can reply; admin only views reviews + host replies. */
  mode?: 'host' | 'admin'
}

const authorDisplayName = (review: EventReview) => {
  const name = [review.user?.firstName, review.user?.lastName].filter(Boolean).join(' ').trim()

  return name || texts.events.guest
}

const EventReviewsPanel = ({ eventId, endsAt, mode = 'host' }: EventReviewsPanelProps) => {
  const isAdmin = mode === 'admin'
  const [reviews, setReviews] = useState<EventReview[]>([])
  const [isLoading, setIsLoading] = useState(true)
  const [isLoadingMore, setIsLoadingMore] = useState(false)
  const [page, setPage] = useState(1)
  const [totalItems, setTotalItems] = useState(0)
  const [replyTarget, setReplyTarget] = useState<EventReview | null>(null)
  const [replyBody, setReplyBody] = useState('')
  const [isSaving, setIsSaving] = useState(false)

  const replyWindowOpen = !isAdmin && !!endsAt && isWithinHostReplyWindow(endsAt)

  const fetchPage = useCallback(
    async (nextPage: number, options?: { errorMode: 'silent' }) => {
      if (isAdmin) {
        return LIST_ADMIN_EVENT_REVIEWS_PAGE(eventId, nextPage, EVENT_REVIEWS_PAGE_SIZE, options)
      }

      return LIST_EVENT_REVIEWS_PAGE(eventId, nextPage, EVENT_REVIEWS_PAGE_SIZE, options)
    },
    [eventId, isAdmin]
  )

  const load = useCallback(async () => {
    setIsLoading(true)
    const result = await fetchPage(1)

    if (result.ok) {
      setReviews(result.data.items)
      setTotalItems(result.data.totalItemsCount)
      setPage(1)
    }
    setIsLoading(false)
  }, [fetchPage])

  const loadMore = async () => {
    if (isLoadingMore || reviews.length >= totalItems) return
    setIsLoadingMore(true)
    const nextPage = page + 1
    const result = await fetchPage(nextPage, { errorMode: 'silent' })

    if (result.ok) {
      setReviews((current) => {
        const seen = new Set(current.map((review) => review.id))

        return [...current, ...result.data.items.filter((review) => !seen.has(review.id))]
      })
      setPage(nextPage)
    }
    setIsLoadingMore(false)
  }

  useEffect(() => {
    void load()
  }, [load])

  const openReply = (review: EventReview) => {
    if (!replyWindowOpen) {
      addToast({ title: texts.errors.codes.HOST_REPLY_WINDOW_EXPIRED, color: 'warning' })

      return
    }
    setReplyTarget(review)
    setReplyBody(review.hostReplyBody ?? '')
  }

  const saveReply = async () => {
    if (!replyTarget) return
    const trimmed = replyBody.trim()

    if (!trimmed) {
      addToast({ title: texts.reviews.replyBodyRequired, color: 'warning' })

      return
    }

    setIsSaving(true)
    const result = await HOST_REPLY_REVIEW(replyTarget.id, { hostReplyBody: trimmed })

    setIsSaving(false)
    if (!result.ok) return

    addToast({ title: texts.reviews.replySaved, color: 'success' })
    setReplyTarget(null)
    setReviews((current) => current.map((review) => (review.id === result.data.id ? result.data : review)))
  }

  const clearReply = async () => {
    if (!replyTarget) return
    setIsSaving(true)
    const result = await HOST_REPLY_REVIEW(replyTarget.id, { hostReplyBody: null })

    setIsSaving(false)
    if (!result.ok) return

    addToast({ title: texts.reviews.replyDeleted, color: 'success' })
    setReplyTarget(null)
    setReviews((current) => current.map((review) => (review.id === result.data.id ? result.data : review)))
  }

  if (isLoading) {
    return <p className={`mt-4 text-sm ${isAdmin ? 'text-text-muted' : 'text-secondary-20'}`}>{texts.reviews.loading}</p>
  }

  if (reviews.length === 0) {
    return (
      <div className="mt-4">
        {isAdmin ? (
          <AdminState
            description={texts.reviews.hostEmptyDescription}
            title={texts.reviews.hostEmptyTitle}
            variant="empty"
          />
        ) : (
          <ConsumerState
            description={texts.reviews.hostEmptyDescription}
            title={texts.reviews.hostEmptyTitle}
            variant="empty"
          />
        )}
      </div>
    )
  }

  return (
    <div className="mt-4 space-y-3">
      {!isAdmin && !replyWindowOpen ? (
        <p className="text-sm font-semibold text-fourth-700">{texts.errors.codes.HOST_REPLY_WINDOW_EXPIRED}</p>
      ) : null}

      <ul className="space-y-3">
        {reviews.map((review) => {
          const statusPresentation = isAdmin ? getReviewStatus(review.status) : null

          return (
            <ReviewCard
              key={review.id}
              authorAvatarUrl={review.user?.avatarUrl}
              authorName={authorDisplayName(review)}
              authorUserId={review.user?.id}
              body={review.body ?? (isAdmin ? texts.reviews.ratingOnly : null)}
              className={isAdmin ? 'admin-surface space-y-2 p-4' : 'consumer-surface space-y-2 p-4'}
              createdAt={review.createdAt}
              footer={
                replyWindowOpen ? (
                  <Button
                    className="mt-3 min-h-11"
                    size="sm"
                    variant="flat"
                    onClick={() => {
                      openReply(review)
                    }}
                  >
                    {review.hostReplyBody ? texts.reviews.editReply : texts.common.reply}
                  </Button>
                ) : statusPresentation ? (
                  <div className="mt-3">
                    <StatusChip
                      chipColor={statusPresentation.chipColor}
                      label={statusPresentation.label}
                    />
                  </div>
                ) : null
              }
              hostReplyBody={review.hostReplyBody}
              rating={review.rating}
              tone={isAdmin ? 'organizer' : 'consumer'}
            />
          )
        })}
      </ul>

      {reviews.length < totalItems ? (
        <div className="flex justify-center">
          <Button
            isLoading={isLoadingMore}
            variant="flat"
            onClick={() => void loadMore()}
          >
            {texts.reviews.loadMore}
          </Button>
        </div>
      ) : null}

      {!isAdmin ? (
        <ConsumerModal
          acceptBtnDisabled={!replyBody.trim() || isSaving}
          acceptBtnText={texts.reviews.saveReply}
          footerChildren={
            replyTarget?.hostReplyBody ? (
              <Button
                color="danger"
                disabled={isSaving}
                size="sm"
                variant="flat"
                onClick={() => void clearReply()}
              >
                {texts.reviews.deleteReply}
              </Button>
            ) : null
          }
          isLoading={isSaving}
          isOpen={!!replyTarget}
          rejectBtnText={texts.common.close}
          title={texts.reviews.replyModalTitle}
          onAccept={() => void saveReply()}
          onOpenChange={(open) => {
            if (!open) setReplyTarget(null)
          }}
          onReject={() => {
            setReplyTarget(null)
          }}
        >
          <Input
            generalType="textarea"
            label={texts.reviews.replyBodyLabel}
            name="hostReplyBody"
            textAreaMinRows={3}
            value={replyBody}
            onValueChange={(next) => {
              setReplyBody(coerceToString(next))
            }}
          />
        </ConsumerModal>
      ) : null}
    </div>
  )
}

export default EventReviewsPanel