import { createContext, useCallback, useContext, useEffect, useState, type ReactNode } from "react";
import { api, type Me } from "./api";

interface AuthState {
  me: Me | null;
  loading: boolean;
  refresh: () => Promise<void>;
  setMe: (me: Me | null) => void;
  logout: () => Promise<void>;
  can: (perm: string) => boolean;
}

const AuthContext = createContext<AuthState | null>(null);

export function AuthProvider({ children }: { children: ReactNode }) {
  const [me, setMe] = useState<Me | null>(null);
  const [loading, setLoading] = useState(true);

  const refresh = useCallback(async () => {
    try {
      setMe(await api.get<Me>("/api/auth/me"));
    } catch {
      setMe(null);
    } finally {
      setLoading(false);
    }
  }, []);

  useEffect(() => {
    void refresh();
    const onUnauthorized = () => setMe(null);
    window.addEventListener("pg-unauthorized", onUnauthorized);
    return () => window.removeEventListener("pg-unauthorized", onUnauthorized);
  }, [refresh]);

  const logout = async () => {
    await api.post("/api/auth/logout");
    setMe(null);
  };
  const can = (perm: string) => !!me?.permissions.includes(perm);

  return (
    <AuthContext.Provider value={{ me, loading, refresh, setMe, logout, can }}>
      {children}
    </AuthContext.Provider>
  );
}

export function useAuth() {
  const ctx = useContext(AuthContext);
  if (!ctx) throw new Error("AuthProvider missing");
  return ctx;
}