import React, { createContext, useCallback, useContext, useEffect, useState } from 'react';
import { getCurrentUser } from '../api';
import { CurrentUser, Role } from '../types';

interface AuthState {
  user: CurrentUser | null;
  loading: boolean;
  refresh: () => Promise<void>;
  clear: () => void;
  hasRole: (...roles: Role[]) => boolean;
}

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

export const AuthProvider: React.FC<{ children: React.ReactNode }> = ({ children }) => {
  const [user, setUser] = useState<CurrentUser | null>(null);
  const [loading, setLoading] = useState(true);

  const refresh = useCallback(async () => {
    setLoading(true);
    try {
      setUser(await getCurrentUser());
    } catch {
      setUser(null);
    } finally {
      setLoading(false);
    }
  }, []);

  const clear = useCallback(() => setUser(null), []);

  const hasRole = useCallback(
    (...roles: Role[]) => !!user && roles.some((r) => user.roles.includes(r)),
    [user],
  );

  useEffect(() => {
    void refresh();
  }, [refresh]);

  return (
    <AuthContext.Provider value={{ user, loading, refresh, clear, hasRole }}>
      {children}
    </AuthContext.Provider>
  );
};

export function useAuth(): AuthState {
  const ctx = useContext(AuthContext);
  if (!ctx) {
    throw new Error('useAuth must be used within AuthProvider');
  }
  return ctx;
}