package cn.wise.sc.cement.business.filter;

import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.util.AntPathMatcher;
import org.springframework.util.FileCopyUtils;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import sun.misc.BASE64Decoder;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

public class SwaggerInterceptor extends HandlerInterceptorAdapter {
	private String username;
	private String password;

	public SwaggerInterceptor(String username, String password) {
		this.username = username;
		this.password = password;
	}

	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
		String authorization = request.getHeader("Authorization");
		boolean isAuthSuccess = httpBasicAuth(authorization);
		if (!isAuthSuccess) {
			response.setCharacterEncoding("utf-8");
			response.setStatus(401);
//            response.setStatus(401,"Unauthorized");
			response.setHeader("WWW-authenticate", "Basic realm=\"Realm\"");
			try (PrintWriter writer = response.getWriter()) {
				writer.print("Forbidden, unauthorized user");
			}
		}
		return isAuthSuccess;
	}

	public boolean httpBasicAuth(String authorization) throws IOException {
		if (authorization != null && authorization.split(" ").length == 2) {
			String userAndPass = new String(new BASE64Decoder().decodeBuffer(authorization.split(" ")[1]));
			String username = userAndPass.split(":").length == 2 ? userAndPass.split(":")[0] : null;
			String password = userAndPass.split(":").length == 2 ? userAndPass.split(":")[1] : null;
			if (this.username.equals(username) && this.password.equals(password)) {
				return true;
			}
		}
		return false;
	}

	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
		String uri = request.getRequestURI();
		AntPathMatcher pathMatcher = new AntPathMatcher();
		if (!pathMatcher.match("/swagger-ui.html", uri) && !pathMatcher.match("/webjars/**", uri)) {
			response.setStatus(404);
			return;
		}
		ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
		Resource[] resources = resolver.getResources("classpath:/META-INF/resources" + uri);
		if (resources != null && resources.length > 0) {
			FileCopyUtils.copy(resources[0].getInputStream(), response.getOutputStream());
		} else {
			response.setStatus(404);
		}
	}
}
