import okhttp3.*;
import retrofit2.*;
import retrofit2.converter.gson.GsonConverterFactory;

public class RedditAuthService {
    private static final String BASE_URL = "https://www.reddit.com/api/v1/";
    private static final String CLIENT_ID = "your_client_id";
    private static final String CLIENT_SECRET = "your_client_secret"; // 如果是脚本应用则为空字符串
    
    public interface RedditAuthApi {
        @FormUrlEncoded
        @POST("access_token")
        Call<ResponseBody> getAccessToken(
            @Field("grant_type") String grantType,
            @Field("username") String username,
            @Field("password") String password,
            @Header("Authorization") String authHeader
        );
    }
    
    public static void main(String[] args) {
        // 创建OkHttpClient
        OkHttpClient okHttpClient = new OkHttpClient.Builder()
            .addInterceptor(new Interceptor() {
                @Override
                public Response intercept(Chain chain) throws IOException {
                    Request original = chain.request();
                    Request request = original.newBuilder()
                        .header("User-Agent", "YourAppName/0.1 by YourRedditUsername")
                        .method(original.method(), original.body())
                        .build();
                    return chain.proceed(request);
                }
            })
            .build();
        
        // 创建Retrofit实例
        Retrofit retrofit = new Retrofit.Builder()
            .baseUrl(BASE_URL)
            .client(okHttpClient)
            .addConverterFactory(GsonConverterFactory.create())
            .build();
        
        RedditAuthApi api = retrofit.create(RedditAuthApi.class);
        
        // 创建Basic Auth头
        String credentials = Credentials.basic(CLIENT_ID, CLIENT_SECRET);
        
        // 调用API
        Call<ResponseBody> call = api.getAccessToken(
            "password", // grant_type
            "your_username",
            "your_password",
            credentials
        );
        
        try {
            Response<ResponseBody> response = call.execute();
            if (response.isSuccessful()) {
                System.out.println("Success: " + response.body().string());
            } else {
                System.out.println("Error: " + response.errorBody().string());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

@FormUrlEncoded
@POST("access_token")
Call<ResponseBody> refreshAccessToken(
    @Field("grant_type") String grantType,
    @Field("refresh_token") String refreshToken,
    @Header("Authorization") String authHeader
);

@FormUrlEncoded
@POST("access_token")
Call<ResponseBody> getAppOnlyAccessToken(
    @Field("grant_type") String grantType,
    @Header("Authorization") String authHeader
);