// lib/auth-client.ts

const API_BASE_URL =
  process.env.NEXT_PUBLIC_API_BASE_URL ?? "";

export type AuthUser = {
  id: number;
  email: string;
  displayName?: string | null;
  role: string;
};

export type AuthPayload = {
  accessToken: string;
  refreshToken?: string;
  userId: number;
  email: string;
  displayName?: string | null;
  role: string;
};

export type RegisterInput = {
  email: string;
  password: string;
  displayName?: string;
};

export type LoginInput = {
  email: string;
  password: string;
};

const AUTH_STORAGE_KEY = "armory-auth";

export function storeAuth(payload: AuthPayload) {
  if (typeof window === "undefined") return;
  const user: AuthUser = {
    id: payload.userId,
    email: payload.email,
    displayName: payload.displayName,
    role: payload.role,
  };

  const toStore = {
    user,
    accessToken: payload.accessToken,
    refreshToken: payload.refreshToken ?? null,
  };

  window.localStorage.setItem(AUTH_STORAGE_KEY, JSON.stringify(toStore));
}

export function loadStoredAuth():
  | { user: AuthUser; accessToken: string; refreshToken: string | null }
  | null {
  if (typeof window === "undefined") return null;
  try {
    const raw = window.localStorage.getItem(AUTH_STORAGE_KEY);
    if (!raw) return null;
    const parsed = JSON.parse(raw);
    if (!parsed.user || !parsed.accessToken) return null;
    return {
      user: parsed.user as AuthUser,
      accessToken: parsed.accessToken as string,
      refreshToken: parsed.refreshToken ?? null,
    };
  } catch {
    return null;
  }
}

export function clearStoredAuth() {
  if (typeof window === "undefined") return;
  window.localStorage.removeItem(AUTH_STORAGE_KEY);
}

async function handleAuthResponse(res: Response): Promise<AuthPayload> {
  if (!res.ok) {
    let message = `Request failed (${res.status})`;
    try {
      const body = await res.json();
      if (body?.message) message = body.message;
    } catch {
      // ignore
    }
    throw new Error(message);
  }

  return (await res.json()) as AuthPayload;
}

export async function apiRegister(input: RegisterInput): Promise<AuthPayload> {
  const res = await fetch(`${API_BASE_URL}/api/auth/register`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      Accept: "application/json",
    },
    body: JSON.stringify(input),
  });

  return handleAuthResponse(res);
}

export async function apiLogin(input: LoginInput): Promise<AuthPayload> {
  const res = await fetch(`${API_BASE_URL}/api/auth/login`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      Accept: "application/json",
    },
    body: JSON.stringify(input),
  });

  return handleAuthResponse(res);
}