package org.oxerr.spring.security.wechat.authentication;
   
   import org.oxerr.spring.security.wechat.core.AuthDenyException;
   import org.oxerr.spring.security.wechat.core.WeChatMessageSource;
   import org.oxerr.spring.security.wechat.core.userdetails.WeChatUserDetailsService;
   import org.springframework.beans.factory.InitializingBean;
   import org.springframework.context.MessageSource;
   import org.springframework.context.MessageSourceAware;
   import org.springframework.context.support.MessageSourceAccessor;
  import org.springframework.security.authentication.AuthenticationProvider;
  import org.springframework.security.core.Authentication;
  import org.springframework.security.core.AuthenticationException;
  import org.springframework.security.core.userdetails.UserDetails;
  import org.springframework.util.Assert;
  
  public class WeChatAuthenticationProvider implements AuthenticationProvider,
  		InitializingBean, MessageSourceAware {
  
  	protected MessageSourceAccessor messages = WeChatMessageSource.getAccessor();
  	private final WeChatUserDetailsService weChatUserDetailsService;
  
  	public WeChatAuthenticationProvider(WeChatUserDetailsService weChatUserDetailsService) {
  		this.weChatUserDetailsService = weChatUserDetailsService;
  	}
  
  	/**
  	 * {@inheritDoc}
  	 */
  	@Override
  	public Authentication authenticate(final Authentication authentication)
  			throws AuthenticationException {
  		final WeChatAuthenticationToken authenticationToken = (WeChatAuthenticationToken) authentication;
  
  		final String code = authenticationToken.getCredentials();
  
  		if (code.equals("authdeny")) {
  			throw new AuthDenyException(messages.getMessage(
  					"WeChatAuthenticationProvider.authdeny",
  					"User denied."));
  
  		}
  
  		final UserDetails userDetails = weChatUserDetailsService.loadUserByCode(code);
  		return new WeChatAuthenticationToken(userDetails);
  	}
  
  	/**
  	 * {@inheritDoc}
  	 */
  	@Override
  	public boolean supports(Class<?> authentication) {
  		return WeChatAuthenticationToken.class.isAssignableFrom(authentication);
  	}
  
  	/**
  	 * {@inheritDoc}
  	 */
  	@Override
  	public void afterPropertiesSet() throws Exception {
  		Assert.notNull(this.weChatUserDetailsService, "A weChatUserDetailsService must be set.");
  	}
  
  	/**
  	 * {@inheritDoc}
  	 */
  	@Override
  	public void setMessageSource(MessageSource messageSource) {
  		this.messages = new MessageSourceAccessor(messageSource);
  	}
  
  }