/*
 *  Copyright (c) 2019-2020, 冷冷 (wangiegie@gmail.com).
 *  <p>
 *  Licensed under the GNU Lesser General Public License 3.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *  <p>
 * https://www.gnu.org/licenses/lgpl.html
 *  <p>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.pig4cloud.pig.common.core.util;

import cn.hutool.core.codec.Base64;
import cn.hutool.json.JSONUtil;
import com.pig4cloud.pig.common.core.exception.CheckedException;
import lombok.SneakyThrows;
import lombok.experimental.UtilityClass;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.util.Assert;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.method.HandlerMethod;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.nio.charset.StandardCharsets;


/**
 * Miscellaneous utilities for web applications.
 *
 * @author L.cm
 */
@Slf4j
@UtilityClass
public class WebUtils extends org.springframework.web.util.WebUtils {
	private final String BASIC_ = "Basic ";
	private final String UNKNOWN = "unknown";

	/**
	 * 判断是否ajax请求
	 * spring ajax 返回含有 ResponseBody 或者 RestController注解
	 *
	 * @param handlerMethod HandlerMethod
	 * @return 是否ajax请求
	 */
	public boolean isBody(HandlerMethod handlerMethod) {
		ResponseBody responseBody = ClassUtils.getAnnotation(handlerMethod, ResponseBody.class);
		return responseBody != null;
	}

	/**
	 * 读取cookie
	 *
	 * @param name cookie name
	 * @return cookie value
	 */
	public String getCookieVal(String name) {
		HttpServletRequest request = WebUtils.getRequest();
		Assert.notNull(request, "request from RequestContextHolder is null");
		return getCookieVal(request, name);
	}

	/**
	 * 读取cookie
	 *
	 * @param request HttpServletRequest
	 * @param name    cookie name
	 * @return cookie value
	 */
	public String getCookieVal(HttpServletRequest request, String name) {
		Cookie cookie = getCookie(request, name);
		return cookie != null ? cookie.getValue() : null;
	}

	/**
	 * 清除 某个指定的cookie
	 *
	 * @param response HttpServletResponse
	 * @param key      cookie key
	 */
	public void removeCookie(HttpServletResponse response, String key) {
		setCookie(response, key, null, 0);
	}

	/**
	 * 设置cookie
	 *
	 * @param response        HttpServletResponse
	 * @param name            cookie name
	 * @param value           cookie value
	 * @param maxAgeInSeconds maxage
	 */
	public void setCookie(HttpServletResponse response, String name, String value, int maxAgeInSeconds) {
		Cookie cookie = new Cookie(name, value);
		cookie.setPath("/");
		cookie.setMaxAge(maxAgeInSeconds);
		cookie.setHttpOnly(true);
		response.addCookie(cookie);
	}

	/**
	 * 获取 HttpServletRequest
	 *
	 * @return {HttpServletRequest}
	 */
	public HttpServletRequest getRequest() {
		return ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
	}

	/**
	 * 获取 HttpServletResponse
	 *
	 * @return {HttpServletResponse}
	 */
	public HttpServletResponse getResponse() {
		return ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getResponse();
	}

	/**
	 * 返回json
	 *
	 * @param response HttpServletResponse
	 * @param result   结果对象
	 */
	public void renderJson(HttpServletResponse response, Object result) {
		renderJson(response, result, MediaType.APPLICATION_JSON_VALUE);
	}

	/**
	 * 返回json
	 *
	 * @param response    HttpServletResponse
	 * @param result      结果对象
	 * @param contentType contentType
	 */
	public void renderJson(HttpServletResponse response, Object result, String contentType) {
		response.setCharacterEncoding("UTF-8");
		response.setContentType(contentType);
		try (PrintWriter out = response.getWriter()) {
			out.append(JSONUtil.toJsonStr(result));
		} catch (IOException e) {
			log.error(e.getMessage(), e);
		}
	}


	/**
	 * 从request 获取CLIENT_ID
	 *
	 * @return
	 */
	@SneakyThrows
	public String[] getClientId(ServerHttpRequest request) {
		String header = request.getHeaders().getFirst(HttpHeaders.AUTHORIZATION);

		if (header == null || !header.startsWith(BASIC_)) {
			throw new CheckedException("请求头中client信息为空");
		}
		byte[] base64Token = header.substring(6).getBytes("UTF-8");
		byte[] decoded;
		try {
			decoded = Base64.decode(base64Token);
		} catch (IllegalArgumentException e) {
			throw new CheckedException(
				"Failed to decode basic authentication token");
		}

		String token = new String(decoded, StandardCharsets.UTF_8);

		int delim = token.indexOf(":");

		if (delim == -1) {
			throw new CheckedException("Invalid basic authentication token");
		}
		return new String[]{token.substring(0, delim), token.substring(delim + 1)};
	}
}

