'use client'

import { useRef, useEffect } from 'react'
import {
  formatMessageDate,
  getContactInitials,
  getRoleLabel,
  getRoleColor,
  type Conversation,
  type Message,
  type Contact,
} from '@/lib/MessagesContext'
import { EmojiPicker } from './EmojiPicker'
import { TemplatesDropdown } from './TemplatesDropdown'

interface ChatAreaProps {
  isDark: boolean
  currentConversation: Conversation | null | undefined
  currentContact: Contact | undefined
  groupedMessages: { date: string; messages: Message[] }[]
  messageInput: string
  sendWithEmail: boolean
  isSending: boolean
  showEmojiPicker: boolean
  showTemplates: boolean
  templates: { id: string; name: string; content: string }[]
  setMessageInput: (val: string) => void
  setSendWithEmail: (val: boolean) => void
  setShowEmojiPicker: (val: boolean) => void
  setShowTemplates: (val: boolean) => void
  setShowContactInfo: (val: boolean) => void
  showContactInfo: boolean
  handleSendMessage: () => void
  handleEmojiSelect: (emoji: string) => void
  handleContextMenu: (e: React.MouseEvent, messageId: string) => void
  getSenderName: (senderId: string) => string
  pinConversation: (id: string) => void
  muteConversation: (id: string) => void
  setShowNewConversation: (val: boolean) => void
}

export function ChatArea({
  isDark, currentConversation, currentContact, groupedMessages,
  messageInput, sendWithEmail, isSending, showEmojiPicker, showTemplates, templates,
  setMessageInput, setSendWithEmail, setShowEmojiPicker, setShowTemplates,
  setShowContactInfo, showContactInfo,
  handleSendMessage, handleEmojiSelect, handleContextMenu,
  getSenderName, pinConversation, muteConversation, setShowNewConversation,
}: ChatAreaProps) {
  const messagesEndRef = useRef<HTMLDivElement>(null)
  const inputRef = useRef<HTMLTextAreaElement>(null)

  useEffect(() => {
    messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' })
  }, [groupedMessages])

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

  return (
    <div className={`flex-1 backdrop-blur-xl border rounded-3xl flex flex-col overflow-hidden ${
      isDark
        ? 'bg-white/10 border-white/20'
        : 'bg-white/70 border-black/10 shadow-xl'
    }`}>
      {currentConversation ? (
        <>
          {/* Chat Header */}
          <ChatHeader isDark={isDark} conversation={currentConversation}
            contact={currentContact} showContactInfo={showContactInfo}
            setShowContactInfo={setShowContactInfo}
            pinConversation={pinConversation} muteConversation={muteConversation} />

          {/* Messages */}
          <div className={`flex-1 overflow-y-auto p-4 space-y-6 ${
            isDark
              ? 'bg-gradient-to-b from-transparent to-black/10'
              : 'bg-gradient-to-b from-transparent to-slate-50/50'
          }`}>
            {groupedMessages.length === 0 ? (
              <div className={`text-center py-12 ${isDark ? 'text-white/40' : 'text-slate-400'}`}>
                <div className="w-20 h-20 mx-auto mb-4 rounded-full flex items-center justify-center text-4xl bg-gradient-to-br from-green-500/20 to-emerald-500/20">
                  👋
                </div>
                <p className="font-medium text-lg">Noch keine Nachrichten</p>
                <p className="text-sm mt-1">Starten Sie die Konversation!</p>
              </div>
            ) : (
              groupedMessages.map((group, groupIndex) => (
                <MessageGroup key={groupIndex} isDark={isDark} group={group}
                  currentConversation={currentConversation}
                  getSenderName={getSenderName}
                  handleContextMenu={handleContextMenu} />
              ))
            )}
            <div ref={messagesEndRef} />
          </div>

          {/* Message Input */}
          <MessageInput isDark={isDark} messageInput={messageInput} sendWithEmail={sendWithEmail}
            isSending={isSending} showEmojiPicker={showEmojiPicker} showTemplates={showTemplates}
            templates={templates} inputRef={inputRef}
            setMessageInput={setMessageInput} setSendWithEmail={setSendWithEmail}
            setShowEmojiPicker={setShowEmojiPicker} setShowTemplates={setShowTemplates}
            handleSendMessage={handleSendMessage} handleEmojiSelect={handleEmojiSelect}
            handleKeyDown={handleKeyDown} />
        </>
      ) : (
        <EmptyState isDark={isDark} setShowNewConversation={setShowNewConversation} />
      )}
    </div>
  )
}

// ============================================
// SUB-COMPONENTS
// ============================================

function ChatHeader({ isDark, conversation, contact, showContactInfo, setShowContactInfo, pinConversation, muteConversation }: {
  isDark: boolean; conversation: Conversation; contact: Contact | undefined
  showContactInfo: boolean; setShowContactInfo: (val: boolean) => void
  pinConversation: (id: string) => void; muteConversation: (id: string) => void
}) {
  return (
    <div className={`p-4 border-b ${isDark ? 'border-white/10' : 'border-slate-200'}`}>
      <div className="flex items-center justify-between">
        <div className="flex items-center gap-3">
          <div className="relative">
            <div className={`w-12 h-12 rounded-full flex items-center justify-center text-lg font-semibold ${
              conversation.is_group
                ? isDark
                  ? 'bg-gradient-to-br from-purple-500/30 to-pink-500/30 text-purple-300'
                  : 'bg-gradient-to-br from-purple-100 to-pink-100 text-purple-700'
                : contact?.online
                  ? isDark
                    ? 'bg-gradient-to-br from-green-500/30 to-emerald-500/30 text-green-300'
                    : 'bg-gradient-to-br from-green-100 to-emerald-100 text-green-700'
                  : isDark
                    ? 'bg-slate-700 text-slate-300'
                    : 'bg-slate-200 text-slate-600'
            }`}>
              {conversation.title ? getContactInitials(conversation.title) : '?'}
            </div>
            {!conversation.is_group && contact?.online && (
              <span className="absolute bottom-0 right-0 w-3 h-3 bg-green-500 rounded-full border-2 border-white dark:border-slate-900" />
            )}
          </div>
          <div>
            <h3 className={`font-semibold ${isDark ? 'text-white' : 'text-slate-900'}`}>
              {conversation.title || 'Unbenannt'}
            </h3>
            <div className="flex items-center gap-2">
              {conversation.typing ? (
                <span className={`text-sm ${isDark ? 'text-green-400' : 'text-green-600'}`}>schreibt...</span>
              ) : contact ? (
                <>
                  <span className={`text-xs px-2 py-0.5 rounded-full ${getRoleColor(contact.role, isDark)}`}>
                    {getRoleLabel(contact.role)}
                  </span>
                  {contact.student_name && (
                    <span className={`text-xs ${isDark ? 'text-white/60' : 'text-slate-500'}`}>
                      • {contact.student_name}
                    </span>
                  )}
                  {contact.online && (
                    <span className={`text-xs ${isDark ? 'text-green-400' : 'text-green-600'}`}>• Online</span>
                  )}
                </>
              ) : conversation.is_group && (
                <span className={`text-sm ${isDark ? 'text-white/60' : 'text-slate-500'}`}>
                  {conversation.participant_ids.length} Mitglieder
                </span>
              )}
            </div>
          </div>
        </div>

        {/* Actions */}
        <div className="flex items-center gap-2">
          <HeaderButton isDark={isDark} active={conversation.pinned ?? false}
            activeColor="amber" onClick={() => pinConversation(conversation.id)}
            title={conversation.pinned ? 'Nicht mehr anheften' : 'Anheften'}>
            <svg className="w-5 h-5" fill={conversation.pinned ? 'currentColor' : 'none'} stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M5 5a2 2 0 012-2h10a2 2 0 012 2v16l-7-3.5L5 21V5z" />
            </svg>
          </HeaderButton>
          <HeaderButton isDark={isDark} active={conversation.muted ?? false}
            activeColor="red" onClick={() => muteConversation(conversation.id)}
            title={conversation.muted ? 'Ton aktivieren' : 'Stummschalten'}>
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              {conversation.muted ? (
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M5.586 15H4a1 1 0 01-1-1v-4a1 1 0 011-1h1.586l4.707-4.707C10.923 3.663 12 4.109 12 5v14c0 .891-1.077 1.337-1.707.707L5.586 15z M17 14l2-2m0 0l2-2m-2 2l-2-2m2 2l2 2" />
              ) : (
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M15.536 8.464a5 5 0 010 7.072M18.364 5.636a9 9 0 010 12.728M5.586 15H4a1 1 0 01-1-1v-4a1 1 0 011-1h1.586l4.707-4.707C10.923 3.663 12 4.109 12 5v14c0 .891-1.077 1.337-1.707.707L5.586 15z" />
              )}
            </svg>
          </HeaderButton>
          <HeaderButton isDark={isDark} active={showContactInfo}
            activeColor="green" onClick={() => setShowContactInfo(!showContactInfo)}>
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
            </svg>
          </HeaderButton>
        </div>
      </div>
    </div>
  )
}

function HeaderButton({ isDark, active, activeColor, onClick, title, children }: {
  isDark: boolean; active: boolean; activeColor: string
  onClick: () => void; title?: string; children: React.ReactNode
}) {
  const activeClasses: Record<string, string> = {
    amber: isDark ? 'bg-amber-500/20 text-amber-300' : 'bg-amber-100 text-amber-700',
    red: isDark ? 'bg-red-500/20 text-red-300' : 'bg-red-100 text-red-700',
    green: isDark ? 'bg-green-500/20 text-green-300' : 'bg-green-100 text-green-700',
  }
  return (
    <button onClick={onClick} title={title}
      className={`p-2 rounded-xl transition-all ${
        active
          ? activeClasses[activeColor]
          : isDark
            ? 'hover:bg-white/10 text-white/60'
            : 'hover:bg-slate-100 text-slate-400'
      }`}>
      {children}
    </button>
  )
}

function MessageGroup({ isDark, group, currentConversation, getSenderName, handleContextMenu }: {
  isDark: boolean; group: { date: string; messages: Message[] }
  currentConversation: Conversation
  getSenderName: (id: string) => string
  handleContextMenu: (e: React.MouseEvent, id: string) => void
}) {
  return (
    <div>
      <div className="flex items-center justify-center mb-4">
        <span className={`px-4 py-1.5 rounded-full text-xs font-medium ${
          isDark ? 'bg-white/10 text-white/60' : 'bg-slate-200 text-slate-600'
        }`}>
          {group.date}
        </span>
      </div>
      <div className="space-y-3">
        {group.messages.map((msg) => {
          const isSelf = msg.sender_id === 'self'
          const isGroupMsg = currentConversation.is_group && !isSelf
          return (
            <div key={msg.id} className={`flex ${isSelf ? 'justify-end' : 'justify-start'}`}
              onContextMenu={(e) => handleContextMenu(e, msg.id)}>
              <div className={`max-w-[70%] ${isSelf ? 'order-2' : ''}`}>
                {isGroupMsg && (
                  <span className={`text-xs ml-3 mb-1 block ${isDark ? 'text-purple-400' : 'text-purple-600'}`}>
                    {getSenderName(msg.sender_id)}
                  </span>
                )}
                <div className={`rounded-2xl px-4 py-2.5 shadow-sm ${
                  isSelf
                    ? 'bg-gradient-to-r from-green-500 to-emerald-500 text-white rounded-br-md'
                    : isDark
                      ? 'bg-white/10 text-white rounded-bl-md'
                      : 'bg-white text-slate-900 rounded-bl-md shadow-lg'
                }`}>
                  <p className="whitespace-pre-wrap break-words">{msg.content}</p>
                  {msg.reactions && msg.reactions.length > 0 && (
                    <div className="flex gap-1 mt-2">
                      {msg.reactions.map((r, i) => (
                        <span key={i} className={`text-sm px-1.5 py-0.5 rounded-full ${isDark ? 'bg-white/20' : 'bg-slate-100'}`}>
                          {r.emoji}
                        </span>
                      ))}
                    </div>
                  )}
                  <div className={`flex items-center gap-2 mt-1 ${
                    isSelf ? 'text-white/70 justify-end' : isDark ? 'text-white/40' : 'text-slate-400'
                  }`}>
                    <span className="text-xs">
                      {new Date(msg.timestamp).toLocaleTimeString('de-DE', { hour: '2-digit', minute: '2-digit' })}
                    </span>
                    {isSelf && (
                      <>
                        {msg.delivered && (
                          <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M5 13l4 4L19 7" />
                          </svg>
                        )}
                        {msg.email_sent && <span className="text-xs">✉️</span>}
                      </>
                    )}
                  </div>
                </div>
              </div>
            </div>
          )
        })}
      </div>
    </div>
  )
}

function MessageInput({ isDark, messageInput, sendWithEmail, isSending, showEmojiPicker, showTemplates, templates, inputRef,
  setMessageInput, setSendWithEmail, setShowEmojiPicker, setShowTemplates,
  handleSendMessage, handleEmojiSelect, handleKeyDown }: {
  isDark: boolean; messageInput: string; sendWithEmail: boolean; isSending: boolean
  showEmojiPicker: boolean; showTemplates: boolean
  templates: { id: string; name: string; content: string }[]
  inputRef: React.RefObject<HTMLTextAreaElement | null>
  setMessageInput: (val: string) => void; setSendWithEmail: (val: boolean) => void
  setShowEmojiPicker: (val: boolean) => void; setShowTemplates: (val: boolean) => void
  handleSendMessage: () => void; handleEmojiSelect: (emoji: string) => void
  handleKeyDown: (e: React.KeyboardEvent) => void
}) {
  return (
    <div className={`p-4 border-t ${isDark ? 'border-white/10' : 'border-slate-200'}`}>
      <div className="flex items-center gap-2 mb-3">
        <button onClick={() => setSendWithEmail(!sendWithEmail)}
          className={`flex items-center gap-2 px-3 py-1.5 rounded-xl text-sm transition-all ${
            sendWithEmail
              ? isDark ? 'bg-blue-500/20 text-blue-300' : 'bg-blue-100 text-blue-700'
              : isDark ? 'bg-white/5 text-white/40 hover:bg-white/10' : 'bg-slate-100 text-slate-400 hover:bg-slate-200'
          }`}>
          <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M3 8l7.89 5.26a2 2 0 002.22 0L21 8M5 19h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v10a2 2 0 002 2z" />
          </svg>
          E-Mail
        </button>
      </div>

      <div className="flex items-end gap-2">
        <div className="relative">
          <button onClick={() => { setShowEmojiPicker(!showEmojiPicker); setShowTemplates(false) }}
            className={`p-3 rounded-2xl transition-all ${
              showEmojiPicker
                ? isDark ? 'bg-green-500/20 text-green-300' : 'bg-green-100 text-green-700'
                : isDark ? 'bg-white/5 text-white/60 hover:bg-white/10' : 'bg-slate-100 text-slate-500 hover:bg-slate-200'
            }`}>
            <span className="text-xl">😊</span>
          </button>
          {showEmojiPicker && (
            <EmojiPicker onSelect={handleEmojiSelect} onClose={() => setShowEmojiPicker(false)} isDark={isDark} />
          )}
        </div>

        <div className="relative">
          <button onClick={() => { setShowTemplates(!showTemplates); setShowEmojiPicker(false) }}
            className={`p-3 rounded-2xl transition-all ${
              showTemplates
                ? isDark ? 'bg-purple-500/20 text-purple-300' : 'bg-purple-100 text-purple-700'
                : isDark ? 'bg-white/5 text-white/60 hover:bg-white/10' : 'bg-slate-100 text-slate-500 hover:bg-slate-200'
            }`}>
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M9 12h6m-6 4h6m2 5H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z" />
            </svg>
          </button>
          {showTemplates && (
            <TemplatesDropdown templates={templates}
              onSelect={(content) => { setMessageInput(content); setShowTemplates(false); inputRef.current?.focus() }}
              isDark={isDark} />
          )}
        </div>

        <textarea ref={inputRef} value={messageInput}
          onChange={(e) => setMessageInput(e.target.value)} onKeyDown={handleKeyDown}
          placeholder="Nachricht schreiben..." rows={1}
          className={`flex-1 px-4 py-3 rounded-2xl border resize-none transition-all ${
            isDark
              ? 'bg-white/5 border-white/10 text-white placeholder:text-white/40 focus:border-green-500/50'
              : 'bg-white border-slate-200 text-slate-900 placeholder:text-slate-400 focus:border-green-500'
          } focus:outline-none focus:ring-2 focus:ring-green-500/20`}
          style={{ maxHeight: '120px' }} />

        <button onClick={handleSendMessage} disabled={!messageInput.trim() || isSending}
          className={`p-3 rounded-2xl transition-all ${
            messageInput.trim() && !isSending
              ? 'bg-gradient-to-r from-green-500 to-emerald-500 text-white shadow-lg hover:shadow-green-500/30'
              : isDark
                ? 'bg-white/5 text-white/30 cursor-not-allowed'
                : 'bg-slate-100 text-slate-300 cursor-not-allowed'
          }`}>
          {isSending ? (
            <svg className="w-6 h-6 animate-spin" fill="none" viewBox="0 0 24 24">
              <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" />
              <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z" />
            </svg>
          ) : (
            <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 19l9 2-9-18-9 18 9-2zm0 0v-8" />
            </svg>
          )}
        </button>
      </div>
    </div>
  )
}

function EmptyState({ isDark, setShowNewConversation }: { isDark: boolean; setShowNewConversation: (val: boolean) => void }) {
  return (
    <div className="flex-1 flex items-center justify-center">
      <div className={`text-center max-w-md px-8 ${isDark ? 'text-white/40' : 'text-slate-400'}`}>
        <div className="w-24 h-24 mx-auto mb-6 rounded-full flex items-center justify-center text-5xl bg-gradient-to-br from-green-500/20 to-emerald-500/20">
          💬
        </div>
        <h3 className={`text-2xl font-bold mb-3 ${isDark ? 'text-white' : 'text-slate-900'}`}>
          BreakPilot Messenger
        </h3>
        <p className="text-sm leading-relaxed">
          Kommunizieren Sie sicher mit Eltern und Kollegen.
          Waehlen Sie eine Konversation aus der Liste oder starten Sie eine neue Unterhaltung.
        </p>
        <button onClick={() => setShowNewConversation(true)}
          className="mt-6 px-6 py-3 bg-gradient-to-r from-green-500 to-emerald-500 text-white rounded-2xl font-medium shadow-lg hover:shadow-green-500/30 transition-all">
          Neue Nachricht
        </button>
      </div>
    </div>
  )
}
