import { NextRequest, NextResponse } from "next/server";
import { cookies } from "next/headers";
import {
  COOKIE_ACCESS,
  COOKIE_REFRESH,
  COOKIE_OPTS,
  ACCESS_MAX_AGE,
  REFRESH_MAX_AGE,
} from "@/lib/auth-cookies";

const BASE_URL =
  process.env.BASE_API_URL ??
  process.env.NEXT_PUBLIC_BASE_API_URL ??
  "http://127.0.0.1:8080";

export async function POST(request: NextRequest) {
  try {
    const body = await request.json();
    const { email, password } = body as { email?: string; password?: string };
    if (!email || !password) {
      return NextResponse.json(
        { error: "E-posta ve şifre gerekli." },
        { status: 400 }
      );
    }

    let res: Response;
    try {
      res = await fetch(`${BASE_URL}/api/v1/auth/login`, {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
          accept: "application/json",
        },
        body: JSON.stringify({ email: String(email).trim(), password }),
      });
    } catch (fetchErr) {
      const msg =
        process.env.NODE_ENV === "development" && fetchErr instanceof Error
          ? `Backend erişilemedi: ${fetchErr.message} (URL: ${BASE_URL})`
          : "Giriş servisi şu an kullanılamıyor.";
      return NextResponse.json({ error: msg }, { status: 502 });
    }

    let data: unknown;
    try {
      const text = await res.text();
      data = text ? JSON.parse(text) : {};
    } catch {
      data = {};
    }

    if (!res.ok) {
      const message =
        (data as { detail?: string })?.detail ?? "Giriş başarısız";
      return NextResponse.json(
        { error: message },
        { status: res.status >= 400 ? res.status : 500 }
      );
    }

    const access_token = (data as { access_token?: string })?.access_token;
    const refresh_token = (data as { refresh_token?: string })?.refresh_token;
    const user = (data as { user?: unknown })?.user;

    if (!access_token || !refresh_token) {
      return NextResponse.json(
        {
          error:
            process.env.NODE_ENV === "development"
              ? "Backend token döndürmedi."
              : "Giriş yanıtı geçersiz.",
        },
        { status: 502 }
      );
    }

    const cookieStore = await cookies();
    cookieStore.set(COOKIE_ACCESS, access_token, {
      ...COOKIE_OPTS,
      maxAge: ACCESS_MAX_AGE,
    });
    cookieStore.set(COOKIE_REFRESH, refresh_token, {
      ...COOKIE_OPTS,
      maxAge: REFRESH_MAX_AGE,
    });

    return NextResponse.json({ user });
  } catch (e) {
    const message =
      process.env.NODE_ENV === "development" && e instanceof Error
        ? e.message
        : "Sunucu hatası.";
    return NextResponse.json({ error: message }, { status: 500 });
  }
}