'use client'

import { useCallback, useMemo, useState } from 'react'
import { useInfiniteQuery, useQuery } from '@tanstack/react-query'
import { useParams } from 'next/navigation'

import DateSeparator from '@/app/(dashboard)/chat-oversight/[id]/_components/DateSeparator'
import Button from '@/components/formElements/Button'
import AdminState from '@/components/feedback/AdminState'
import { DetailSkeleton, ListSkeleton } from '@/components/feedback/LoadingState'
import PageNavbar from '@/components/layouts/PageNavbar'
import StatusChip from '@/components/ui/StatusChip'
import { APP_ROUTES } from '@/constants/routes'
import { groupMessagesForDisplay } from '@/features/chat/groupMessagesForDisplay'
import { formatPersonName } from '@/helpers'
import { formatIranianMobile, formatPersianDate } from '@/lib/formatters'
import useAdminChatSocket from '@/hooks/useAdminChatSocket'
import {
  GET_ADMIN_CONVERSATION,
  GET_ADMIN_CONVERSATION_MESSAGES,
  GET_ADMIN_CONVERSATION_PARTICIPANTS,
  type AdminChatMessage,
} from '@/services/adminChat'

import AdminMessageBubble from './_components/AdminMessageBubble'

const ChatOversightDetailPage = () => {
  const params = useParams<{ id: string }>()
  const conversationId = params.id
  const [liveMessages, setLiveMessages] = useState<AdminChatMessage[]>([])
  const handleLiveMessage = useCallback((message: AdminChatMessage) => {
    setLiveMessages((current) => (current.some((item) => item.id === message.id) ? current : [...current, message]))
  }, [])
  const socket = useAdminChatSocket(conversationId, handleLiveMessage)
  const conversationQuery = useQuery({
    queryKey: ['admin', 'chat-oversight', conversationId],
    queryFn: () => GET_ADMIN_CONVERSATION(conversationId),
    enabled: Boolean(conversationId),
  })
  const participantsQuery = useQuery({
    queryKey: ['admin', 'chat-oversight', conversationId, 'participants'],
    queryFn: () => GET_ADMIN_CONVERSATION_PARTICIPANTS(conversationId),
    enabled: Boolean(conversationId),
  })
  const messagesQuery = useInfiniteQuery({
    queryKey: ['admin', 'chat-oversight', conversationId, 'messages'],
    initialPageParam: undefined as string | undefined,
    queryFn: ({ pageParam }) => GET_ADMIN_CONVERSATION_MESSAGES(conversationId, pageParam ? { before: pageParam } : undefined),
    getNextPageParam: (lastPage) => (lastPage.hasMoreBefore ? (lastPage.olderCursor ?? undefined) : undefined),
    enabled: Boolean(conversationId),
  })

  const messages = useMemo(() => {
    const seen = new Set<string>()

    const history = [...(messagesQuery.data?.pages ?? [])].reverse().flatMap((page) => page.items)

    return [...history, ...liveMessages].filter((message) => {
      if (seen.has(message.id)) return false
      seen.add(message.id)

      return true
    })
  }, [liveMessages, messagesQuery.data])

  const displayItems = useMemo(() => groupMessagesForDisplay(messages, { showSenderNames: true }), [messages])

  const conversation = conversationQuery.data
  const participants = useMemo(() => participantsQuery.data ?? [], [participantsQuery.data])
  const participantSideById = useMemo(
    () => new Map(participants.map((participant, index) => [participant.userId, index % 2 === 0 ? 'primary' : 'secondary'] as const)),
    [participants]
  )
  const title = conversation
    ? conversation.type === 'event_group'
      ? conversation.eventTitle || 'گروه رویداد'
      : participants
          .map((participant) => formatPersonName(participant.firstName, participant.lastName, formatIranianMobile(participant.mobile)))
          .join(' و ') || 'گفتگوی خصوصی'
    : 'جزئیات گفتگو'
  const loadError = conversationQuery.error ?? participantsQuery.error ?? messagesQuery.error
  const isInitialLoading = conversationQuery.isLoading || participantsQuery.isLoading || messagesQuery.isLoading

  return (
    <section className="h-full w-full text-right">
      <PageNavbar
        description="حالت نظارت مخفی و فقط‌خواندنی"
        endSlot={
          <Button
            size="sm"
            to={APP_ROUTES.CHAT_OVERSIGHT}
            variant="flat"
          >
            بازگشت به گفتگوها
          </Button>
        }
        pageTitle={title}
      />

      <div className="admin-page-container flex flex-col gap-5">
        <div className="flex flex-wrap items-center justify-between gap-3 rounded-2xl border border-fourth-100 bg-fourth-100 px-4 py-3">
          <div>
            <p className="font-bold text-fourth-900">حالت نظارت — فقط خواندنی</p>
            <p className="mt-1 text-xs leading-6 text-fourth-900">
              مشاهده شما عضویت، اعلان یا تغییر وضعیت خوانده‌شدن برای کاربران ایجاد نمی‌کند و در گزارش فعالیت ادمین ثبت می‌شود.
            </p>
          </div>
          {conversation ? (
            <div className="flex items-center gap-2">
              <StatusChip
                chipColor={socket.status === 'connected' ? 'success' : socket.status === 'error' ? 'danger' : 'warning'}
                label={socket.status === 'connected' ? 'اتصال زنده' : socket.status === 'error' ? 'خطای سوکت' : 'در حال اتصال'}
              />
              <StatusChip
                chipColor={conversation.type === 'event_group' ? 'warning' : 'default'}
                label={conversation.type === 'event_group' ? 'گروه رویداد' : 'گفتگوی خصوصی'}
              />
            </div>
          ) : null}
        </div>

        {socket.error ? (
          <p className="rounded-xl border border-fourth-100 bg-fourth-100 px-3 py-2 text-xs text-fourth-900">
            {socket.error} پیام‌های ذخیره‌شده همچنان از طریق API قابل مشاهده‌اند.
          </p>
        ) : null}

        {isInitialLoading ? (
          <>
            <DetailSkeleton />
            <ListSkeleton count={6} />
          </>
        ) : null}

        {!isInitialLoading && loadError ? (
          <div className="admin-surface">
            <AdminState
              actionLabel="تلاش دوباره"
              description={loadError instanceof Error ? loadError.message : 'دریافت اطلاعات گفتگو ناموفق بود.'}
              title="خطا در دریافت گفتگو"
              variant="error"
              onAction={() => {
                void conversationQuery.refetch()
                void participantsQuery.refetch()
                void messagesQuery.refetch()
              }}
            />
          </div>
        ) : null}

        {!isInitialLoading && !loadError && conversation ? (
          <>
            <section className="admin-surface p-4">
              <div className="mb-4 flex flex-wrap items-center justify-between gap-2">
                <h2 className="text-base font-bold text-foreground">اعضای گفتگو</h2>
                <span className="text-xs text-muted">{conversation.memberCount.toLocaleString('fa-IR')} نفر</span>
              </div>
              <div className="grid gap-3 sm:grid-cols-2 xl:grid-cols-3">
                {participants.map((participant) => (
                  <div
                    key={participant.userId}
                    className="rounded-xl border border-border bg-surface-secondary px-3 py-2"
                  >
                    <p className="text-sm font-semibold">{formatPersonName(participant.firstName, participant.lastName, 'کاربر')}</p>
                    <p
                      className="mt-1 text-xs text-muted"
                      dir="ltr"
                    >
                      {formatIranianMobile(participant.mobile)}
                    </p>
                  </div>
                ))}
              </div>
            </section>

            <section className="admin-surface p-4">
              <div className="mb-4 flex flex-wrap items-center justify-between gap-2">
                <h2 className="text-base font-bold text-foreground">پیام‌های گفتگو</h2>
                {conversation.lastMessageAt ? (
                  <span className="text-xs text-muted">آخرین فعالیت: {formatPersianDate(conversation.lastMessageAt)}</span>
                ) : null}
              </div>

              {messagesQuery.hasNextPage ? (
                <div className="mb-4 flex justify-center">
                  <Button
                    isLoading={messagesQuery.isFetchingNextPage}
                    size="sm"
                    variant="flat"
                    onClick={() => void messagesQuery.fetchNextPage()}
                  >
                    بارگذاری پیام‌های قدیمی‌تر
                  </Button>
                </div>
              ) : null}

              {messages.length === 0 ? (
                <AdminState
                  description="هنوز پیامی در این گفتگو ثبت نشده است."
                  title="گفتگو بدون پیام است"
                />
              ) : (
                <div className="rounded-2xl border border-consumer-border bg-consumer-canvas px-3 py-4 sm:px-6">
                  <div className="mx-auto flex w-full max-w-3xl flex-col">
                    {displayItems.map((item) => {
                      if (item.kind === 'date') {
                        return (
                          <DateSeparator
                            key={item.key}
                            label={item.label}
                          />
                        )
                      }

                      return (
                        <AdminMessageBubble
                          key={item.key}
                          isClusterEnd={item.isClusterEnd}
                          isClusterStart={item.isClusterStart}
                          message={item.message}
                          showAvatar={item.showAvatar}
                          showSenderName={item.showSenderName}
                          side={participantSideById.get(item.message.senderId) ?? 'primary'}
                        />
                      )
                    })}
                  </div>
                </div>
              )}
            </section>
          </>
        ) : null}
      </div>
    </section>
  )
}

export default ChatOversightDetailPage