package com.xuqm.im.config;

import com.xuqm.common.security.JwtUtil;
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.simp.config.ChannelRegistration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.messaging.simp.stomp.StompCommand;
import org.springframework.messaging.simp.stomp.StompHeaderAccessor;
import org.springframework.messaging.support.ChannelInterceptor;
import org.springframework.messaging.support.MessageHeaderAccessor;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;

import java.util.List;

@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {

    private final JwtUtil jwtUtil;

    public WebSocketConfig(JwtUtil jwtUtil) {
        this.jwtUtil = jwtUtil;
    }

    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/topic", "/queue");
        registry.setApplicationDestinationPrefixes("/app");
        registry.setUserDestinationPrefix("/user");
    }

    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws/im")
                .setAllowedOriginPatterns("*")
                .withSockJS();
        registry.addEndpoint("/ws/im")
                .setAllowedOriginPatterns("*");
    }

    @Override
    public void configureClientInboundChannel(ChannelRegistration registration) {
        registration.interceptors(new ChannelInterceptor() {
            @Override
            public Message<?> preSend(Message<?> message, MessageChannel channel) {
                StompHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(
                        message, StompHeaderAccessor.class);
                if (accessor != null && StompCommand.CONNECT.equals(accessor.getCommand())) {
                    String token = accessor.getFirstNativeHeader("Authorization");
                    if (token != null && token.startsWith("Bearer ")) {
                        token = token.substring(7);
                        if (jwtUtil.isValid(token)) {
                            String userId = jwtUtil.getSubject(token);
                            UsernamePasswordAuthenticationToken auth =
                                    new UsernamePasswordAuthenticationToken(userId, null,
                                            List.of(new SimpleGrantedAuthority("ROLE_USER")));
                            accessor.setUser(auth);
                        }
                    }
                }
                return message;
            }
        });
    }
}