"use client";

import { useEffect, useRef, useState } from "react";
import { createClient } from "@/lib/supabase/client";
import { sendMessage } from "@/lib/actions/messages";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { cn } from "@/lib/utils";

type Message = {
  id: string;
  conversation_id: string;
  sender_id: string;
  body: string;
  created_at: string;
};

export function ChatWindow({
  conversationId,
  currentUserId,
  initialMessages,
}: {
  conversationId: string;
  currentUserId: string;
  initialMessages: Message[];
}) {
  const [messages, setMessages] = useState<Message[]>(initialMessages);
  const bottomRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    const supabase = createClient();
    const channel = supabase
      .channel(`conversation:${conversationId}`)
      .on(
        "postgres_changes",
        {
          event: "INSERT",
          schema: "public",
          table: "messages",
          filter: `conversation_id=eq.${conversationId}`,
        },
        (payload) => {
          const newMessage = payload.new as Message;
          setMessages((current) => {
            if (current.some((m) => m.id === newMessage.id)) return current;
            return [...current, newMessage];
          });
        }
      )
      .subscribe();

    return () => {
      supabase.removeChannel(channel);
    };
  }, [conversationId]);

  useEffect(() => {
    bottomRef.current?.scrollIntoView({ behavior: "smooth" });
  }, [messages]);

  const sendMessageWithConversation = sendMessage.bind(null, conversationId);

  return (
    <div className="flex h-[60vh] flex-col rounded-lg border sm:h-[70vh]">
      <div className="flex-1 space-y-3 overflow-y-auto p-4">
        {messages.map((message) => {
          const isMine = message.sender_id === currentUserId;
          return (
            <div
              key={message.id}
              className={cn("flex", isMine ? "justify-end" : "justify-start")}
            >
              <div
                className={cn(
                  "max-w-[75%] rounded-lg px-3 py-2 text-sm",
                  isMine
                    ? "bg-primary text-primary-foreground"
                    : "bg-muted"
                )}
              >
                {message.body}
              </div>
            </div>
          );
        })}
        <div ref={bottomRef} />
      </div>
      <form
        action={async (formData) => {
          await sendMessageWithConversation(formData);
          (document.getElementById("chat-input") as HTMLInputElement).value =
            "";
        }}
        className="flex gap-2 border-t p-3"
      >
        <Input
          id="chat-input"
          name="body"
          placeholder="Écris un message..."
          autoComplete="off"
          className="flex-1"
        />
        <Button type="submit">Envoyer</Button>
      </form>
    </div>
  );
}