'use client'

import { useState, useEffect, useMemo } from 'react'
import {
  useMessages,
  formatMessageDate,
  type Conversation,
  type Message,
  type Contact,
} from '@/lib/MessagesContext'

export function useMessagesPage() {
  const messagesCtx = useMessages()
  const {
    contacts,
    conversations,
    messages,
    templates,
    unreadCount,
    recentConversations,
    sendMessage,
    markAsRead,
    createConversation,
    addReaction,
    deleteMessage,
    pinConversation,
    muteConversation,
    currentConversationId,
    setCurrentConversationId,
  } = messagesCtx

  const [messageInput, setMessageInput] = useState('')
  const [sendWithEmail, setSendWithEmail] = useState(false)
  const [isSending, setIsSending] = useState(false)
  const [showNewConversation, setShowNewConversation] = useState(false)
  const [showEmojiPicker, setShowEmojiPicker] = useState(false)
  const [showTemplates, setShowTemplates] = useState(false)
  const [showContactInfo, setShowContactInfo] = useState(false)
  const [searchQuery, setSearchQuery] = useState('')
  const [contextMenu, setContextMenu] = useState<{ x: number; y: number; messageId: string } | null>(null)

  // Current conversation data
  const currentConversation = conversations.find(c => c.id === currentConversationId)
  const currentMessages = currentConversationId ? (messages[currentConversationId] || []) : []

  // Find contact for conversation
  const getConversationContact = (conv: Conversation): Contact | undefined => {
    if (conv.is_group) return undefined
    return contacts.find(c => conv.participant_ids.includes(c.id))
  }

  // Get sender name for group messages
  const getSenderName = (senderId: string): string => {
    if (senderId === 'self') return 'Du'
    const contact = contacts.find(c => c.id === senderId)
    return contact?.name?.split(' ')[0] || 'Unbekannt'
  }

  // Filter conversations by search
  const filteredConversations = useMemo(() => {
    if (!searchQuery) return recentConversations
    const q = searchQuery.toLowerCase()
    return recentConversations.filter(c =>
      c.title?.toLowerCase().includes(q) ||
      c.last_message?.toLowerCase().includes(q)
    )
  }, [recentConversations, searchQuery])

  // Group messages by date
  const groupedMessages = useMemo(() => {
    const groups: { date: string; messages: Message[] }[] = []
    let currentDate = ''

    for (const msg of currentMessages) {
      const msgDate = formatMessageDate(msg.timestamp)
      if (msgDate !== currentDate) {
        currentDate = msgDate
        groups.push({ date: msgDate, messages: [] })
      }
      groups[groups.length - 1].messages.push(msg)
    }

    return groups
  }, [currentMessages])

  // Select conversation
  const selectConversation = async (conv: Conversation) => {
    setCurrentConversationId(conv.id)
    if (conv.unread_count > 0) {
      await markAsRead(conv.id)
    }
    setShowContactInfo(false)
  }

  // Send message
  const handleSendMessage = async () => {
    if (!messageInput.trim() || !currentConversationId) return

    setIsSending(true)
    await sendMessage(currentConversationId, messageInput.trim(), sendWithEmail)
    setMessageInput('')
    setIsSending(false)
    setShowEmojiPicker(false)
    setShowTemplates(false)
  }

  // Insert emoji
  const handleEmojiSelect = (emoji: string) => {
    setMessageInput(prev => prev + emoji)
  }

  // Start new conversation
  const handleStartConversation = async (contact: Contact) => {
    const conv = await createConversation(contact.id)
    if (conv) {
      setCurrentConversationId(conv.id)
      setShowNewConversation(false)
    }
  }

  // Handle context menu
  const handleContextMenu = (e: React.MouseEvent, messageId: string) => {
    e.preventDefault()
    setContextMenu({ x: e.clientX, y: e.clientY, messageId })
  }

  // Close context menu on click outside
  useEffect(() => {
    const handleClick = () => setContextMenu(null)
    if (contextMenu) {
      document.addEventListener('click', handleClick)
      return () => document.removeEventListener('click', handleClick)
    }
  }, [contextMenu])

  const currentContact = currentConversation ? getConversationContact(currentConversation) : undefined

  return {
    // Context data
    contacts, templates, unreadCount,
    currentConversationId, currentConversation, currentContact,
    filteredConversations, groupedMessages,
    // UI state
    messageInput, setMessageInput,
    sendWithEmail, setSendWithEmail,
    isSending,
    showNewConversation, setShowNewConversation,
    showEmojiPicker, setShowEmojiPicker,
    showTemplates, setShowTemplates,
    showContactInfo, setShowContactInfo,
    searchQuery, setSearchQuery,
    contextMenu, setContextMenu,
    // Actions
    selectConversation,
    handleSendMessage,
    handleEmojiSelect,
    handleStartConversation,
    handleContextMenu,
    getSenderName,
    getConversationContact,
    // From context
    pinConversation,
    muteConversation,
    deleteMessage,
  }
}