package ru.digitalbanana.demoresourceserver.config;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
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.core.Authentication;
import org.springframework.security.oauth2.jwt.Jwt;
import org.springframework.security.oauth2.jwt.JwtDecoder;
import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationConverter;
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 org.springframework.web.socket.config.annotation.WebSocketTransportRegistration;
/**
 * Web Socket configuration
 * Created by dima on 8/12/16.
 */
@Configuration
@Order(Ordered.HIGHEST_PRECEDENCE + 99)
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {

    @Autowired
    private JwtDecoder jwtDecoder;

    @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())) {
                    List<String> authorization = accessor.getNativeHeader("Authorization");
                    String accessToken = authorization != null ? authorization.get(0).split(" ")[1] : "";
                    Jwt jwt = jwtDecoder.decode(accessToken);
                    JwtAuthenticationConverter converter = new JwtAuthenticationConverter();
                    Authentication authentication = converter.convert(jwt);
                    accessor.setUser(authentication);
                }
                return message;
            }
        });
    }
    
    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/simple");
        registry.setApplicationDestinationPrefixes("/app");
    }

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

    @Override
    public void configureWebSocketTransport(WebSocketTransportRegistration registration) {
        registration.setSendBufferSizeLimit(1024 * 512 * 1024); // default : 512 * 1024

    }
}