'use client'

import { useState, useEffect, useCallback } from 'react'
import { Button } from '@/components/ui/button'
import { Badge } from '@/components/ui/badge'
import { Bell, Check, X, Clock } from 'lucide-react'
import {
  Popover,
  PopoverContent,
  PopoverTrigger,
} from '@/components/ui/popover'
import { getPendingShareRequests, respondToShareRequest } from '@/app/actions/notes'
import { toast } from 'sonner'
import { useNoteRefresh } from '@/context/NoteRefreshContext'
import { cn } from '@/lib/utils'
import { useLanguage } from '@/lib/i18n'

interface ShareRequest {
  id: string
  status: string
  permission: string
  createdAt: Date
  note: {
    id: string
    title: string | null
    content: string
    color: string
    createdAt: Date
  }
  sharer: {
    id: string
    name: string | null
    email: string
    image: string | null
  }
}

export function NotificationPanel() {
  const { triggerRefresh } = useNoteRefresh()
  const { t } = useLanguage()
  const [requests, setRequests] = useState<ShareRequest[]>([])
  const [isLoading, setIsLoading] = useState(false)
  const [open, setOpen] = useState(false)

  const loadRequests = useCallback(async () => {
    try {
      const data = await getPendingShareRequests()
      setRequests(data as any)
    } catch (error: any) {
      console.error('Failed to load share requests:', error)
    }
  }, [])

  useEffect(() => {
    loadRequests()
    const interval = setInterval(loadRequests, 10000)
    const onFocus = () => loadRequests()
    window.addEventListener('focus', onFocus)
    return () => {
      clearInterval(interval)
      window.removeEventListener('focus', onFocus)
    }
  }, [loadRequests])

  const pendingCount = requests.length

  const handleAccept = async (shareId: string) => {
    try {
      await respondToShareRequest(shareId, 'accept')
      setRequests(prev => prev.filter(r => r.id !== shareId))
      toast.success(t('notification.accepted'), {
        description: t('collaboration.nowHasAccess', { name: 'Note' }),
        duration: 3000,
      })
      triggerRefresh()
      setOpen(false)
    } catch (error: any) {
      console.error('[NOTIFICATION] Error:', error)
      toast.error(error.message || t('general.error'))
    }
  }

  const handleDecline = async (shareId: string) => {
    try {
      await respondToShareRequest(shareId, 'decline')
      setRequests(prev => prev.filter(r => r.id !== shareId))
      toast.info(t('notification.declined'))
      if (requests.length <= 1) setOpen(false)
    } catch (error: any) {
      console.error('[NOTIFICATION] Error:', error)
      toast.error(error.message || t('general.error'))
    }
  }

  return (
    <Popover open={open} onOpenChange={setOpen}>
      <PopoverTrigger asChild>
        <Button
          variant="ghost"
          size="sm"
          className="relative h-9 w-9 p-0 hover:bg-accent/50 transition-all duration-200"
        >
          <Bell className="h-4 w-4 transition-transform duration-200 hover:scale-110" />
          {pendingCount > 0 && (
            <Badge
              variant="destructive"
              className="absolute -top-1 -right-1 h-5 w-5 flex items-center justify-center p-0 text-xs animate-pulse shadow-lg"
            >
              {pendingCount > 9 ? '9+' : pendingCount}
            </Badge>
          )}
        </Button>
      </PopoverTrigger>
      <PopoverContent align="end" className="w-80 p-0">
        <div className="px-4 py-3 border-b bg-gradient-to-r from-primary/5 to-primary/10 dark:from-primary/10 dark:to-primary/15">
          <div className="flex items-center justify-between">
            <div className="flex items-center gap-2">
              <Bell className="h-4 w-4 text-primary dark:text-primary-foreground" />
              <span className="font-semibold text-sm">{t('notification.notifications')}</span>
            </div>
            {pendingCount > 0 && (
              <Badge className="bg-primary hover:bg-primary/90 text-primary-foreground shadow-md">
                {pendingCount}
              </Badge>
            )}
          </div>
        </div>

        {isLoading ? (
          <div className="p-6 text-center text-sm text-muted-foreground">
            <div className="animate-spin h-6 w-6 border-2 border-primary border-t-transparent rounded-full mx-auto mb-2" />
          </div>
        ) : requests.length === 0 ? (
          <div className="p-6 text-center text-sm text-muted-foreground">
            <Bell className="h-10 w-10 mx-auto mb-3 opacity-30" />
            <p className="font-medium">{t('notification.noNotifications') || 'No new notifications'}</p>
          </div>
        ) : (
          <div className="max-h-96 overflow-y-auto">
            {requests.map((request) => (
              <div
                key={request.id}
                className="p-4 border-b last:border-0 hover:bg-accent/50 transition-colors duration-150"
              >
                <div className="flex items-start gap-3 mb-3">
                  <div className="h-8 w-8 rounded-full bg-gradient-to-br from-blue-500 to-indigo-600 flex items-center justify-center text-white font-semibold text-xs shadow-md shrink-0">
                    {(request.sharer.name || request.sharer.email)[0].toUpperCase()}
                  </div>
                  <div className="flex-1 min-w-0">
                    <p className="text-sm font-semibold truncate">
                      {request.sharer.name || request.sharer.email}
                    </p>
                    <p className="text-xs text-muted-foreground truncate mt-0.5">
                      {t('notification.shared', { title: request.note.title || t('notification.untitled') })}
                    </p>
                  </div>
                </div>

                <div className="flex gap-2 mt-3">
                  <button
                    onClick={() => handleDecline(request.id)}
                    className={cn(
                      "flex-1 h-9 px-4 text-xs font-semibold rounded-lg",
                      "border border-border bg-background",
                      "text-muted-foreground",
                      "hover:bg-muted hover:text-foreground",
                      "transition-all duration-200",
                      "flex items-center justify-center gap-1.5",
                      "active:scale-95"
                    )}
                  >
                    <X className="h-3.5 w-3.5" />
                    {t('notification.decline') || t('general.cancel')}
                  </button>
                  <button
                    onClick={() => handleAccept(request.id)}
                    className={cn(
                      "flex-1 h-9 px-4 text-xs font-semibold rounded-lg",
                      "bg-primary text-primary-foreground",
                      "hover:bg-primary/90",
                      "shadow-sm hover:shadow",
                      "transition-all duration-200",
                      "flex items-center justify-center gap-1.5",
                      "active:scale-95"
                    )}
                  >
                    <Check className="h-3.5 w-3.5" />
                    {t('notification.accept') || t('general.confirm')}
                  </button>
                </div>

                <div className="flex items-center gap-1.5 mt-3 text-xs text-muted-foreground">
                  <Clock className="h-3 w-3" />
                  <span>{new Date(request.createdAt).toLocaleDateString()}</span>
                </div>
              </div>
            ))}
          </div>
        )}
      </PopoverContent>
    </Popover>
  )
}