import React, { useState, useEffect, useRef } from 'react'
import {
  FaChevronLeft,
  FaChevronRight,
  FaMapMarkerAlt,
  FaCalendarAlt,
  FaUsers,
  FaExpand,
  FaCommentAlt,
  FaPaperPlane,
} from 'react-icons/fa'
import { Button, Dialog } from '@/components/ui'
import { useDialogContext } from '@/components/ui/Dialog/Dialog'
import { EventCommentDto, EventDto } from '@/proxy/intranet/models'
import useLocale from '@/utils/hooks/useLocale'
import { currentLocalDate } from '@/utils/dateUtils'
import Avatar from '@/components/ui/Avatar/Avatar'
import { AVATAR_URL } from '@/constants/app.constant'
import { intranetService } from '@/services/intranet.service'
import dayjs from 'dayjs'
import relativeTime from 'dayjs/plugin/relativeTime'
import { useLocalization } from '@/utils/hooks/useLocalization'
import ImageLightbox from './ImageLightbox'
import LikeButton from './LikeButton'
import { imageSrc } from './widgetUtils'

dayjs.extend(relativeTime)

interface EventModalProps {
  event: EventDto
  onClose: () => void
  onLikeChange?: (event: EventDto) => void
}

function EventModalContent({ event, onClose, onLikeChange }: EventModalProps) {
  const currentLocale = useLocale()
  const photos = (event.photos || '').split('|').filter(Boolean)
  const { translate } = useLocalization()
  const { isMaximized } = useDialogContext()

  // Photo slider state
  const [activePhoto, setActivePhoto] = useState(0)
  const [lightboxOpen, setLightboxOpen] = useState(false)
  const [lightboxIndex, setLightboxIndex] = useState(0)

  // Comments state
  const [comments, setComments] = useState<EventCommentDto[]>(event.comments || [])
  const [commentText, setCommentText] = useState('')
  const [submitting, setSubmitting] = useState(false)
  const commentInputRef = useRef<HTMLTextAreaElement>(null)
  const commentsEndRef = useRef<HTMLDivElement>(null)

  // Likes state
  const [likes, setLikes] = useState(event.likes)
  const [isLiked, setIsLiked] = useState(event.isLiked)
  const [liking, setLiking] = useState(false)

  useEffect(() => {
    // Refresh comments from API on open
    intranetService.getEventComments(event.id).then((res) => {
      if (res.data) setComments(res.data)
    })
  }, [event.id])

  const scrollToBottom = () => {
    commentsEndRef.current?.scrollIntoView({ behavior: 'smooth' })
  }

  const handleSubmitComment = async () => {
    if (!commentText.trim() || submitting) return
    setSubmitting(true)
    try {
      const res = await intranetService.createEventComment(event.id, commentText.trim())
      if (res.data) {
        setComments((prev) => [...prev, res.data!])
        setCommentText('')
        setTimeout(scrollToBottom, 100)
      }
    } finally {
      setSubmitting(false)
    }
  }

  const handleKeyDown = (e: React.KeyboardEvent<HTMLTextAreaElement>) => {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault()
      handleSubmitComment()
    }
  }

  const handleLike = async () => {
    if (liking) return
    setLiking(true)
    // Optimistic update
    setIsLiked((prev) => !prev)
    setLikes((prev) => (isLiked ? Math.max(0, prev - 1) : prev + 1))
    try {
      const res = await intranetService.likeEvent(event.id)
      if (res.data) {
        const updatedEvent = {
          ...event,
          likes: res.data.likes,
          isLiked: res.data.isLiked,
        }
        setLikes(updatedEvent.likes)
        setIsLiked(updatedEvent.isLiked)
        onLikeChange?.(updatedEvent)
      }
    } catch {
      // Revert on error
      setIsLiked((prev) => !prev)
      setLikes((prev) => (isLiked ? prev + 1 : Math.max(0, prev - 1)))
    } finally {
      setLiking(false)
    }
  }

  const openLightbox = (idx: number) => {
    setLightboxIndex(idx)
    setLightboxOpen(true)
  }

  const closeLightbox = () => setLightboxOpen(false)

  return (
    <>
      <Dialog.Body className="flex flex-col min-h-0">
        {/* Header */}
        <div className="pb-3 pr-16 border-b border-gray-200 dark:border-gray-700 flex-shrink-0">
          <div className="flex items-start justify-between gap-4">
            <div className="flex-1 min-w-0">
              <h2 className="text-xl font-bold text-gray-900 dark:text-white leading-tight">
                {event.name}
              </h2>
              <div className="flex flex-wrap items-center gap-4 mt-2 text-sm text-gray-600 dark:text-gray-400">
                <span className="flex items-center gap-1">
                  <FaCalendarAlt className="w-3.5 h-3.5 text-green-500" />
                  {currentLocalDate(event.date, currentLocale || 'tr')}
                </span>
                {event.place && (
                  <span className="flex items-center gap-1">
                    <FaMapMarkerAlt className="w-3.5 h-3.5 text-red-500" />
                    {event.place}
                  </span>
                )}
                {event.participantsCount > 0 && (
                  <span className="flex items-center gap-1">
                    <FaUsers className="w-3.5 h-3.5 text-blue-500" />
                    {event.participantsCount}
                  </span>
                )}
                <div>
                  <LikeButton
                    onClick={handleLike}
                    disabled={liking}
                    isLiked={isLiked}
                    likes={likes}
                  />
                </div>
              </div>

              {event.user && (
                <div className="flex items-center gap-2 mt-3">
                  <Avatar
                    size={28}
                    shape="circle"
                    src={AVATAR_URL(event.user.id, event.user.tenantId)}
                  />
                  <span className="text-sm font-medium text-gray-700 dark:text-gray-300">
                    {event.user.fullName}
                  </span>
                </div>
              )}
            </div>
          </div>
        </div>

        {/* Scrollable body */}
        <div className={`overflow-y-auto ${isMaximized ? 'flex-1 min-h-0' : 'max-h-[62vh]'}`}>
          {/* Photo Gallery */}
          {photos.length > 0 && (
            <div className="m-3 border-b border-gray-200 dark:border-gray-700">
              {/* Main photo */}
              <div className="relative w-full rounded-lg overflow-hidden dark:bg-gray-900 mb-2 mx-auto">
                <img
                  src={imageSrc(photos[activePhoto])}
                  alt={`${event.name} ${activePhoto + 1}`}
                  className="w-full h-56 object-contain cursor-zoom-in"
                  onClick={() => openLightbox(activePhoto)}
                />
                <Button
                  onClick={() => openLightbox(activePhoto)}
                  variant="plain"
                  shape="none"
                  icon={<FaExpand className="h-4 w-4" />}
                  className="absolute top-2 right-2 !h-7 !w-7 !rounded-lg !px-0 bg-black/50 text-white transition-colors hover:!bg-black/70"
                  title="Tam ekran"
                />
                {photos.length > 1 && (
                  <>
                    <Button
                      onClick={(e) => {
                        e.stopPropagation()
                        setActivePhoto((i) => (i - 1 + photos.length) % photos.length)
                      }}
                      variant="plain"
                      shape="circle"
                      icon={<FaChevronLeft className="h-4 w-4" />}
                      className="absolute left-2 top-1/2 !h-8 !w-8 -translate-y-1/2 !px-0 bg-black/50 text-white transition-colors hover:!bg-black/70"
                    />
                    <Button
                      onClick={(e) => {
                        e.stopPropagation()
                        setActivePhoto((i) => (i + 1) % photos.length)
                      }}
                      variant="plain"
                      shape="circle"
                      icon={<FaChevronRight className="h-4 w-4" />}
                      className="absolute right-2 top-1/2 !h-8 !w-8 -translate-y-1/2 !px-0 bg-black/50 text-white transition-colors hover:!bg-black/70"
                    />
                  </>
                )}
              </div>
              {/* Thumbnail strip */}
              {photos.length > 1 && (
                <div className="flex gap-2 overflow-x-auto pb-1">
                  {photos.map((photo, idx) => (
                    <Button
                      key={idx}
                      onClick={() => setActivePhoto(idx)}
                      variant="plain"
                      shape="none"
                      className={`flex-shrink-0 !h-16 !w-16 !rounded-lg !px-0 overflow-hidden border-2 transition-all ${
                        idx === activePhoto
                          ? 'border-green-500 opacity-100'
                          : 'border-transparent opacity-60 hover:opacity-90'
                      }`}
                    >
                      <img
                        src={imageSrc(photo)}
                        alt={`Thumbnail ${idx + 1}`}
                        className="w-full h-full object-cover"
                      />
                    </Button>
                  ))}
                </div>
              )}
            </div>
          )}

          {/* Description */}
          {event.description && (
            <div className="pb-2 border-b border-gray-200 dark:border-gray-700">
              <p className="text-sm text-gray-700 dark:text-gray-300 whitespace-pre-line">
                {event.description}
              </p>
            </div>
          )}

          {/* Comments Section */}
          <div className="py-3">
            <h3 className="text-sm font-semibold text-gray-900 dark:text-white flex items-center gap-2 mb-2">
              <FaCommentAlt className="w-4 h-4 text-green-500" />
              {translate('::App.Intranet.Events.Comments')} ({comments.length})
            </h3>

            {/* Comment List */}
            <div className="max-h-64 overflow-y-auto">
              {comments.length === 0 ? (
                <p className="text-sm text-gray-400 dark:text-gray-500 text-center">
                  {translate('::App.Intranet.Events.NoComment')}
                </p>
              ) : (
                comments.map((comment) => (
                  <div key={comment.id} className="flex gap-3">
                    {comment.user && (
                      <Avatar
                        size={32}
                        shape="circle"
                        src={AVATAR_URL(comment.user.id, comment.user.tenantId)}
                        className="flex-shrink-0"
                      />
                    )}
                    <div className="flex-1 min-w-0">
                      <div className="bg-gray-50 dark:bg-gray-700/60 rounded-xl px-3 py-2">
                        <p className="text-xs font-semibold text-gray-800 dark:text-gray-200">
                          {comment.user?.fullName ?? 'Kullanıcı'}
                        </p>
                        <p className="text-sm text-gray-700 dark:text-gray-300 mt-0.5 whitespace-pre-line">
                          {comment.content}
                        </p>
                      </div>
                      <p className="text-xs text-gray-400 dark:text-gray-500 mt-1 px-1">
                        {dayjs(comment.creationTime).fromNow()}
                      </p>
                    </div>
                  </div>
                ))
              )}
              <div ref={commentsEndRef} />
            </div>
          </div>
        </div>
      </Dialog.Body>

      <Dialog.Footer className="pt-2 border-t border-gray-200 dark:border-gray-700 flex-shrink-0 flex items-end gap-1">
        <div className="flex flex-1 gap-2 items-end">
          <textarea
            ref={commentInputRef}
            value={commentText}
            autoFocus
            onChange={(e) => setCommentText(e.target.value)}
            onKeyDown={handleKeyDown}
            placeholder={translate('::App.Intranet.Events.EventAttendance')}
            rows={1}
            className="flex-1 resize-none px-2 py-1 text-sm rounded-xl bg-white dark:bg-gray-700 text-gray-900 dark:text-white placeholder-gray-400 transition-colors"
          />
          <Button
            type="button"
            size="sm"
            onClick={handleSubmitComment}
            disabled={!commentText.trim() || submitting}
            variant="solid"
            icon={<FaPaperPlane className="h-4 w-4" />}
          />
        </div>
        <Button
          size="sm"
          onClick={onClose}
          type="button"
          variant="solid"
        >
          {translate('::App.Platform.Close')}
        </Button>
      </Dialog.Footer>

      <ImageLightbox
        images={photos}
        activeIndex={lightboxIndex}
        isOpen={lightboxOpen}
        altPrefix={event.name}
        getSrc={imageSrc}
        onClose={closeLightbox}
        onChangeIndex={setLightboxIndex}
      />
    </>
  )
}

const EventModal: React.FC<EventModalProps> = ({ event, onClose, onLikeChange }) => {
  return (
    <Dialog isOpen onClose={onClose} onRequestClose={onClose} width={768}>
      <EventModalContent event={event} onClose={onClose} onLikeChange={onLikeChange} />
    </Dialog>
  )
}

export default EventModal