/**
 * Copyright 2016 benjobs
 * <p>
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <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 org.opencron.common.utils;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.lang3.StringEscapeUtils;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;


/**
 * 封装各种格式的编码解码工具类.
 *
 * 1.Commons-Codec的 hex/base64 编码
 * 2.自制的base62 编码
 * 3.Commons-Lang的xml/html escape
 * 4.JDK提供的URLEncoder
 *
 * @author calvin
 */
public abstract class Encodes {

    private static final String DEFAULT_URL_ENCODING = "UTF-8";
    private static final char[] BASE62 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".toCharArray();

    /**
     * Hex编码.
     */
    public static String encodeHex(byte[] input) {
        return Hex.encodeHexString(input);
    }

    /**
     * Hex解码.
     */
    public static byte[] decodeHex(String input) {
        try {
            return Hex.decodeHex(input.toCharArray());
        } catch (DecoderException e) {
            throw Exceptions.unchecked(e);
        }
    }

    /**
     * Base64编码.
     */
    public static String encodeBase64(byte[] input) {
        return Base64.encodeBase64String(input);
    }

    /**
     * Base64编码, URL安全(将Base64中的URL非法字符'+'和'/'转为'-'和'_', 见RFC3548).
     */
    public static String encodeUrlSafeBase64(byte[] input) {
        return Base64.encodeBase64URLSafeString(input);
    }

    /**
     * Base64解码.
     */
    public static byte[] decodeBase64(String input) {
        return Base64.decodeBase64(input);
    }

    /**
     * Base62编码。
     */
    public static String encodeBase62(byte[] input) {
        char[] chars = new char[input.length];
        for (int i = 0; i < input.length; i++) {
            chars[i] = BASE62[(input[i] & 0xFF) % BASE62.length];
        }
        return new String(chars);
    }

    /**
     * Html 转码.
     */
    public static String escapeHtml(String html) {
        return StringEscapeUtils.escapeHtml4(html);
    }

    /**
     * Html 解码.
     */
    public static String unescapeHtml(String htmlEscaped) {
        return StringEscapeUtils.unescapeHtml4(htmlEscaped);
    }

    /**
     * Xml 转码.
     */
    public static String escapeXml(String xml) {
        return StringEscapeUtils.escapeXml(xml);
    }

    /**
     * Xml 解码.
     */
    public static String unescapeXml(String xmlEscaped) {
        return StringEscapeUtils.unescapeXml(xmlEscaped);
    }

    /**
     * URL 编码, Encode默认为UTF-8.
     */
    public static String urlEncode(String part) {
        try {
            return URLEncoder.encode(part, DEFAULT_URL_ENCODING);
        } catch (UnsupportedEncodingException e) {
            throw Exceptions.unchecked(e);
        }
    }

    /**
     * URL 解码, Encode默认为UTF-8.
     */
    public static String urlDecode(String part) {

        try {
            return URLDecoder.decode(part, DEFAULT_URL_ENCODING);
        } catch (UnsupportedEncodingException e) {
            throw Exceptions.unchecked(e);
        }
    }
}
