import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import lombok.extern.slf4j.Slf4j;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @ClassName CrosFilter
 */
@Component
@Order(Ordered.HIGHEST_PRECEDENCE)
@Slf4j
public class CrosFilter implements Filter {

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest servletRequest = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) res;
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "POST,GET,OPTIONS,DELETE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers", "Access-Control-Allow-Headers,Content-Length,Accept,Authorization,Content-Type,x-requested-with,sign,saas-token");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        if(servletRequest.getMethod().equals(HttpMethod.OPTIONS.name())){
            response.setStatus(HttpStatus.OK.value());
        }else {
            chain.doFilter(req, res);
        }
    }
}