export const runtime = "nodejs";

import { NextResponse } from "next/server";
import { requireSession } from "@/lib/auth/require";
import { listMessages, sendMessage } from "@/lib/chat/service";
import { saveChatAttachment } from "@/lib/chat/attachments";

export async function GET(_request: Request, { params }: { params: Promise<{ id: string }> }) {
  const { session, response } = await requireSession();
  if (!session) return response;

  const { id } = await params;
  const messages = await listMessages(id, session.user.id);
  if (messages === null) return NextResponse.json({ error: "Forbidden" }, { status: 403 });
  return NextResponse.json(messages);
}

const MAX_ATTACHMENT_BYTES = 25 * 1024 * 1024;

/** Один эндпоинт на текст/вложение/голосовое — форма всегда multipart, поля опциональны в зависимости от того, что отправляет клиент. */
export async function POST(request: Request, { params }: { params: Promise<{ id: string }> }) {
  const { session, response } = await requireSession();
  if (!session) return response;

  const { id } = await params;
  const form = await request.formData().catch(() => null);
  if (!form) return NextResponse.json({ error: "Некорректные данные" }, { status: 400 });

  const body = form.get("body");
  const replyToMessageId = form.get("replyToMessageId");
  const file = form.get("file");
  const kindRaw = form.get("kind");

  const bodyText = typeof body === "string" && body.trim() ? body.trim() : undefined;
  if (!bodyText && !(file instanceof File)) {
    return NextResponse.json({ error: "Пустое сообщение" }, { status: 400 });
  }
  if (file instanceof File && file.size > MAX_ATTACHMENT_BYTES) {
    return NextResponse.json({ error: "Файл слишком большой (максимум 25 МБ)" }, { status: 400 });
  }

  let message;
  try {
    message = await sendMessage(id, session.user.id, {
      body: bodyText,
      replyToMessageId: typeof replyToMessageId === "string" && replyToMessageId ? replyToMessageId : undefined,
    });
  } catch (err) {
    const msg = err instanceof Error ? err.message : "Не удалось отправить сообщение";
    return NextResponse.json({ error: msg }, { status: 403 });
  }

  let attachment = null;
  if (file instanceof File) {
    const kind = kindRaw === "voice" ? "voice" : file.type.startsWith("image/") ? "image" : "file";
    const durationRaw = form.get("durationSeconds");
    const content = Buffer.from(await file.arrayBuffer());
    attachment = await saveChatAttachment({
      messageId: message.id,
      kind,
      fileName: file.name || (kind === "voice" ? "voice-message.webm" : "file"),
      mimeType: file.type || "application/octet-stream",
      content,
      durationSeconds: typeof durationRaw === "string" ? Number(durationRaw) : undefined,
    });
  }

  return NextResponse.json({ message, attachment }, { status: 201 });
}