// app/app/api/auth/login/route.ts
import { NextRequest, NextResponse } from "next/server";
import { setAuthCookies } from "@/lib/auth-cookies";

const BASE = process.env.DIRECTUS_URL!;
const ADMIN_TOKEN = process.env.DIRECTUS_TOKEN_ADMIN_REGISTER!; // for username→email lookup

type DirectusList<T> = { data: T[] };
type LoginResp = { data: { access_token: string; refresh_token: string; expires: number } };
type MeResp = { data: { id: string; email: string | null; username?: string | null } };

async function adminFetch<T=any>(path: string, init?: RequestInit): Promise<T> {
    const res = await fetch(`${BASE}${path}`, {
        ...init,
        headers: {
            "Accept": "application/json",
            "Content-Type": "application/json",
            "Authorization": `Bearer ${ADMIN_TOKEN}`,
            ...(init?.headers || {}),
        },
    });
    const text = await res.text();
    const json = text ? JSON.parse(text) : null;
    if (!res.ok) throw new Error(`Directus ${res.status}: ${text || res.statusText}`);
    return (json ?? {}) as T;
}

async function directusLogin(email: string, password: string): Promise<LoginResp["data"]> {
    const res = await fetch(`${BASE}/auth/login`, {
        method: "POST",
        headers: { "Accept": "application/json", "Content-Type": "application/json" },
        body: JSON.stringify({ email, password }),
    });
    const text = await res.text();
    const json = text ? JSON.parse(text) : null;
    if (!res.ok) throw new Error(`Login failed: ${text || res.statusText}`);
    return json.data;
}

function isEmailLike(s: string) {
    return /^[^@\s]+@[^@\s]+\.[^@\s]+$/.test(s);
}

export async function POST(req: NextRequest) {
    try {
        const body = await req.json().catch(() => ({}));
        const identifier: string = (body?.identifier ?? "").trim(); // username OR email
        const password: string = (body?.password ?? "").trim();

        if (!identifier || !password) {
            return NextResponse.json({ error: "Missing identifier or password." }, { status: 400 });
        }

        let email = identifier;
        let username: string | undefined = undefined;

        if (!isEmailLike(identifier)) {
            // lookup email by username (custom field on directus_users)
            const q = `/users?limit=1&filter[username][_eq]=${encodeURIComponent(identifier)}&fields=id,email,username`;
            const found = await adminFetch<DirectusList<{id:string;email:string|null;username:string|null}>>(q);
            const user = found.data?.[0];
            if (!user?.email) return NextResponse.json({ error: "User not found." }, { status: 404 });
            email = user.email;
            username = user.username || undefined;
        }

        const tokens = await directusLogin(email, password);

        // Fetch /users/me to confirm and obtain username (if email path)
        const meRes = await fetch(`${BASE}/users/me?fields=id,email,username`, {
            headers: { "Authorization": `Bearer ${tokens.access_token}`, "Accept": "application/json" },
        });
        const meText = await meRes.text();
        const me: MeResp = meText ? JSON.parse(meText) : { data: { id: "", email: null, username: null } };

        const user = {
            id: String(me?.data?.id || ""),
            email: me?.data?.email ?? null,
            username: (me?.data?.username as string | null) ?? username ?? email.split("@")[0],
        };

        let res = NextResponse.json({ ok: true, user });
        res = setAuthCookies(res, tokens, user);
        return res;
    } catch (err: any) {
        return NextResponse.json({ error: err?.message || "Login failed" }, { status: 401 });
    }
}