import React, { useEffect, useRef, useState } from 'react';
import { useChatStore } from '../store/chatStore';
import { ChatMessageComponent } from './ChatMessage';
import { useChat } from '../hooks/useChat';
import { useWebRTC } from '../hooks/useWebRTC';
import { MessageSearch } from './MessageSearch';
import { TypingIndicator } from './TypingIndicator';
import { CallButton } from './CallButton';
import { IncomingCallModal } from './IncomingCallModal';
import { ActiveCallBar } from './ActiveCallBar';
import {
  Search,
  X,
  MessageSquare,
  UserPlus,
  Users,
} from 'lucide-react';
import { Button } from '@/components/ui/button';
import { cn } from '@/lib/utils';
import { InviteRoomModal } from './InviteRoomModal';
import { RoomMembersModal } from './RoomMembersModal';
import { useUser } from '@/features/auth/hooks/useUser';
import { adminService } from '@/services/adminService';

interface ChatRoomProps {
  conversationId: string;
}

export const ChatRoom: React.FC<ChatRoomProps> = ({ conversationId }) => {
  const { messages, conversations, userId, incomingCall, activeCall } =
    useChatStore();
  const { fetchHistory, sendRawMessage, wsStatus } = useChat();
  const { data: _user } = useUser();
  const webrtc = useWebRTC({ sendMessage: sendRawMessage });
  const messagesEndRef = useRef<HTMLDivElement>(null);
  const [showSearch, setShowSearch] = useState(false);
  const [showInviteModal, setShowInviteModal] = useState(false);
  const [showMembersModal, setShowMembersModal] = useState(false);
  const [webrtcEnabled, setWebrtcEnabled] = useState(true);
  const [highlightedMessageId, setHighlightedMessageId] = useState<
    string | null
  >(null);
  const highlightTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);

  useEffect(() => {
    let cancelled = false;
    adminService.getClientFeatureFlags().then((flags) => {
      if (cancelled) return;
      const webrtc = flags.find((f) => f.name === 'WEBRTC_CALLS');
      setWebrtcEnabled(webrtc?.enabled ?? true);
    }).catch(() => { if (!cancelled) setWebrtcEnabled(true); });
    return () => { cancelled = true; };
  }, []);

  // Cleanup highlight timeout on unmount
  useEffect(() => {
    return () => {
      if (highlightTimeoutRef.current) {
        clearTimeout(highlightTimeoutRef.current);
      }
    };
  }, []);

  const currentMessages = messages[conversationId] || [];
  const fetchingRef = useRef<{ [key: string]: boolean }>({});

  useEffect(() => {
    if (
      conversationId &&
      !messages[conversationId] &&
      !fetchingRef.current[conversationId]
    ) {
      fetchingRef.current[conversationId] = true;
      fetchHistory(conversationId).finally(() => {
        // Fetch complete
      });
    }
  }, [conversationId, messages[conversationId], fetchHistory]);

  useEffect(() => {
    if (messagesEndRef.current) {
      messagesEndRef.current.scrollIntoView({ behavior: 'smooth' });
    }
  }, [currentMessages.length, conversationId]); // Scroll on new messages or channel switch

  const handleMessageSelect = (messageId: string) => {
    setHighlightedMessageId(messageId);
    const messageElement = document.getElementById(`message-${messageId}`);
    if (messageElement) {
      messageElement.scrollIntoView({ behavior: 'smooth', block: 'center' });
      if (highlightTimeoutRef.current) {
        clearTimeout(highlightTimeoutRef.current);
      }
      highlightTimeoutRef.current = setTimeout(() => setHighlightedMessageId(null), 3000);
    }
  };

  const conversation = conversations.find((c) => c.id === conversationId);
  const isDM =
    conversation?.type === 'direct' && conversation.participants.length === 2;
  const isGroupRoom = conversation && conversation.type !== 'direct';
  const targetUserId =
    isDM && userId
      ? conversation.participants.find((p) => p !== userId) ?? null
      : null;
  const remoteUserName =
    conversation?.name && conversation.name !== 'direct'
      ? conversation.name
      : 'Utilisateur';

  if (!conversationId) {
    return (
      <div className="flex-1 flex flex-col items-center justify-center text-muted-foreground space-y-4 animate-empty-state-in">
        <div className="w-24 h-24 rounded-full bg-muted flex items-center justify-center">
          <MessageSquare className="w-10 h-10 text-muted-foreground" />
        </div>
        <div className="text-center">
          <p className="text-sm font-medium text-foreground mb-1">
            No conversation selected
          </p>
          <p className="text-xs text-muted-foreground">
            Pick a channel from the sidebar to start chatting.
          </p>
        </div>
      </div>
    );
  }

  return (
    <div className="flex-1 flex flex-col h-full overflow-hidden relative">
      <IncomingCallModal
        open={!!incomingCall}
        callerName={remoteUserName}
        onAccept={() =>
          incomingCall &&
          webrtc.acceptCall(
            incomingCall.conversationId,
            incomingCall.callerUserId,
            incomingCall.sdp,
          )
        }
        onReject={() =>
          incomingCall &&
          webrtc.rejectCall(
            incomingCall.conversationId,
            incomingCall.callerUserId,
          )
        }
      />
      {activeCall && (
        <div className="absolute bottom-0 left-0 right-0 z-30">
          <ActiveCallBar
            remoteUserName={remoteUserName}
            isMuted={webrtc.isMuted}
            onToggleMute={webrtc.toggleMute}
            onHangup={() =>
              webrtc.hangup(activeCall.conversationId, activeCall.remoteUserId)
            }
          />
        </div>
      )}
      {/* Search Header Overlay */}
      <div
        className={cn(
          'absolute top-0 left-0 right-0 z-20 px-4 py-2 transition-all duration-[var(--sumi-duration-normal)]',
          showSearch
            ? 'bg-card/90 backdrop-blur-md border-b border-border'
            : 'bg-transparent pointer-events-none',
        )}
      >
        {showSearch ? (
          <div className="flex items-center gap-2 max-w-2xl mx-auto">
            <div className="flex-1">
              <MessageSearch
                conversationId={conversationId}
                onMessageSelect={handleMessageSelect}
              />
            </div>
            <Button
              variant="ghost"
              size="sm"
              onClick={() => setShowSearch(false)}
              className="hover:bg-muted/50"
            >
              <X className="h-4 w-4" />
            </Button>
          </div>
        ) : (
          <div className="flex justify-end items-center gap-2 pointer-events-auto">
            {isGroupRoom && (
              <>
                <Button
                  variant="ghost"
                  size="sm"
                  onClick={() => setShowInviteModal(true)}
                  className="text-muted-foreground/50 hover:text-foreground hover:bg-muted/50 bg-muted/30 backdrop-blur-sm rounded-full h-8 px-4 shadow-[0_0_8px_rgba(26,26,30,0.05)]"
                >
                  <UserPlus className="h-3 w-3 mr-2" />
                  <span className="text-xs font-mono uppercase">Invite</span>
                </Button>
                <Button
                  variant="ghost"
                  size="sm"
                  onClick={() => setShowMembersModal(true)}
                  className="text-muted-foreground/50 hover:text-foreground hover:bg-muted/50 bg-muted/30 backdrop-blur-sm rounded-full h-8 px-4 shadow-[0_0_8px_rgba(26,26,30,0.05)]"
                >
                  <Users className="h-3 w-3 mr-2" />
                  <span className="text-xs font-mono uppercase">Members</span>
                </Button>
              </>
            )}
            {isDM && targetUserId && webrtcEnabled && (
              <CallButton
                conversationId={conversationId}
                targetUserId={targetUserId}
                onCall={() =>
                  webrtc.startCall(conversationId, targetUserId, 'audio')
                }
                disabled={wsStatus !== 'connected'}
                hasTurn={webrtc.nat.loaded ? webrtc.nat.hasTurn : undefined}
              />
            )}
            <Button
              variant="ghost"
              size="sm"
              onClick={() => setShowSearch(true)}
              className="text-muted-foreground/50 hover:text-foreground hover:bg-muted/50 bg-muted/30 backdrop-blur-sm rounded-full h-8 px-4 shadow-[0_0_8px_rgba(26,26,30,0.05)]"
            >
              <Search className="h-3 w-3 mr-2" />
              <span className="text-xs font-mono uppercase">Search Log</span>
            </Button>
          </div>
        )}
      </div>

      <div className="flex-1 overflow-y-auto custom-scrollbar p-6 space-y-4 scroll-smooth">
        {/* Welcome Message for Empty Room */}
        {currentMessages.length === 0 && (
          <div className="flex flex-col items-center justify-center h-layout-lyrics-sm text-center space-y-4 animate-empty-state-in">
            <div className="w-14 h-14 rounded-full bg-muted flex items-center justify-center">
              <MessageSquare className="w-7 h-7 text-muted-foreground" />
            </div>
            <div>
              <p className="text-foreground font-medium">No messages yet</p>
              <p className="text-sm text-muted-foreground mt-1">
                Send the first message to start the conversation.
              </p>
            </div>
          </div>
        )}

        {/* Message Stream */}
        {currentMessages.map((msg) => {
          return (
            <div
              key={msg.id}
              id={`message-${msg.id}`}
              className={cn(
                'transition-all duration-[var(--sumi-duration-slow)] animate-slideUp',
                highlightedMessageId === msg.id &&
                'bg-muted/10 rounded-xl -mx-4 px-4 py-2 ring-1 ring-border/30',
              )}
            >
              <ChatMessageComponent message={msg} />
            </div>
          );
        })}

        <TypingIndicator conversationId={conversationId} />
        <div ref={messagesEndRef} className="h-4" />
      </div>

      {isGroupRoom && (
        <>
          <InviteRoomModal
            open={showInviteModal}
            onOpenChange={setShowInviteModal}
            conversationId={conversationId}
          />
          <RoomMembersModal
            open={showMembersModal}
            onOpenChange={setShowMembersModal}
            conversationId={conversationId}
          />
        </>
      )}
    </div>
  );
};