package org.jeecg.modules.shiro.authc.aop;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.jeecg.modules.shiro.authc.JwtToken;
import org.jeecg.modules.shiro.vo.DefContants;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.RequestMethod;
import lombok.extern.slf4j.Slf4j;

/**
 * @author Scott
 * @create 2018-07-12 15:56
 * @desc   鉴权登录拦截器
 **/
@Slf4j
public class JwtFilter extends BasicHttpAuthenticationFilter {

	/**
	 * 执行登录认证
	 *
	 * @param request
	 * @param response
	 * @param mappedValue
	 * @return
	 */
	@Override
	protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
			try {
				executeLogin(request, response);
				return true;
			} catch (Exception e) {
				throw new AuthenticationException("Token失效，请重新登录", e);
			}
	}

	/**
	 *
	 */
	@Override
	protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
		HttpServletRequest httpServletRequest = (HttpServletRequest) request;
		String token = httpServletRequest.getHeader(DefContants.X_ACCESS_TOKEN);

		JwtToken jwtToken = new JwtToken(token);
		// 提交给realm进行登入，如果错误他会抛出异常并被捕获
		getSubject(request, response).login(jwtToken);
		// 如果没有抛出异常则代表登入成功，返回true
		return true;
	}

	/**
	 * 对跨域提供支持
	 */
	@Override
	protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
		HttpServletRequest httpServletRequest = (HttpServletRequest) request;
		HttpServletResponse httpServletResponse = (HttpServletResponse) response;
		httpServletResponse.setHeader("Access-control-Allow-Origin", httpServletRequest.getHeader("Origin"));
		httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS,PUT,DELETE");
		httpServletResponse.setHeader("Access-Control-Allow-Headers", httpServletRequest.getHeader("Access-Control-Request-Headers"));
		// 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
		if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())) {
			httpServletResponse.setStatus(HttpStatus.OK.value());
			return false;
		}
		return super.preHandle(request, response);
	}
}
