package cn.mb.cloud.gateway.auth;

import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.util.MultiValueMap;

import javax.servlet.http.HttpServletRequest;
import java.util.*;

/**
 * 
 * 接口鉴权工具类
 * 
 * @author gwx 2017-12-23
 *
 */
public class AuthenticationKit {
	public static final String utf8="UTF-8";
	
	/**
	 * 返回64 位 token
	 * 
	 * @param key 自定义安全字符
	 * @return
	 * @throws Exception
	 */
	public static String getToken(String key) throws Exception {
		// 随机生成 32位字符
		String salt = HashKit.generateSaltForSha256();
		// 获取当前时间
		long cur = System.currentTimeMillis();
		// 生成64位token
		String access_token = getToken256(key, salt, cur);
		return access_token;
	}
	
	/**
	 * 返回64 位 token
	 * 
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static String getToken256(String key, String salt, long cur) throws Exception {
		// 生成64位token
		String access_token = HashKit.sha256(salt + cur + key);
		return access_token;
	}

	/**
	 * 返回到秒
	 * 
	 * @return
	 */
	public static String createTimestamp() {
		long l = System.currentTimeMillis();
		return Long.toString(l / 1000);
	}

	/**
	 * 返回noce 不带 短杠"-"
	 * 
	 * @return
	 */
	public static String createNonceStr() {
		return getUUID();
	}

	public static String getUUID() {
		UUID uuid = UUID.randomUUID();
		String str = uuid.toString();
		str = str.replaceAll("-", "");
		return str;
	}

	/**
	 * 组装路径
	 * 
	 * @param params
	 * @return
	 */
	public static String localSignParam(Map<String, Object> params) {
		return localSignUrl(null, params, false);
	}

	
	/**
	 * 组装签名路径
	 * @param url
	 * @param params
	 * @return
	 */
	public static String localSignUrl(String url, Map<String, Object> params, boolean urlEncode) {
		Set<Map.Entry<String, Object>> entries = params.entrySet();
		if(entries.size() == 0){
			return "";
		}

		List<Map.Entry<String, Object>> infoIds = new ArrayList<Map.Entry<String, Object>>(entries);
		// 对所有传入参数按照字段名的 ASCII 码从小到大排序（字典序）
		//Sort all incoming parameters in ascending order according to the ASCII code of the field name (lexicographic order).
		Collections.sort(infoIds, new Comparator<Map.Entry<String, Object>>() {
			public int compare(Map.Entry<String, Object> o1, Map.Entry<String, Object> o2) {
				return (o1.getKey()).toString().compareTo(o2.getKey());
			}
		});
		// 构造签名键值对的格式
		// Format for constructing key-value pairs for signatures
		StringBuilder sb = new StringBuilder();
		for (Map.Entry<String, Object> item : infoIds) {
			if (item.getKey() != null || item.getKey() != "") {
				String key = item.getKey();
				Object val = item.getValue();
				if (!(val == "" || val == null)) {
					sb.append(key + "=" + val + "&");
				}
			}
		}
		return sb.substring(0, sb.length() - 1);
    }


	/**
	 * 加密签名路径生成签名
	 * 
	 * @param signUrl
	 *            /token?appid=12345&timestamp=1512440267&nonce=12345
	 * @param encryptKey
	 * @return
	 * @throws Exception
	 */
	public static String signUrlEncode(String signUrl, String encryptKey) throws Exception {
		byte[] signByte = HMACSHA1.HmacSHA1Encrypt(signUrl, encryptKey);
		String localSign = Base64.getEncoder().encodeToString(signByte);
		return localSign;
	}



	/**
	 * 服务端 获取 客户端请求 组装验证签名
	 * @param delParams 移除不相关 的签名参数
	 * @return
	 */
	public static String getSignUrl(String url, Map<String, Object> queryParams, String... delParams) {
		// 获取相对的访问路径
		//Get the relative access path
		if (queryParams.size() > 0) {
			// 删除 Delete
			for (int i = 0, len = delParams.length; i < len; i++) {
                queryParams.remove(delParams[i]);
			}
			return localSignUrl(url, queryParams, false);
		}
		return null;
	}


	/**
	 * 组装签名路径 客户端测试用
	 * @param url api访问地址 "/apid"
	 * @param appid 
	 * @return
	 */
	public static String getSignUrl(String url, String appid, Map<String, String> queryParas) {
		Map<String, Object> params = new TreeMap<String, Object>();
		params.put("appid", appid);
		params.put("nonce", createNonceStr());
		params.put("timestamp", createTimestamp());
		if(queryParas!=null && queryParas.size()>0){
			params.putAll(queryParas);
		}
		return localSignUrl(url, params, false);
	}
	
	/**
	 * 组装签名路径 客户端测试用
	 * @param url api访问地址 "/apid"
	 * @param appid 
	 * @return
	 */
	public static String getSignUrl(String url, String appid) {
		return getSignUrl(url, appid, "");
	}
	
	/**
	 * 
	 * @param url
	 * @param appid
	 * @param params
	 * @return
	 */
	public static String getSignUrl(String url, String appid, String params) {
		String urlTmp = getSignUrl(url, appid, new HashMap<String,String>());
		return urlTmp + UrlEncoderUtils.encode(params);
	}


}