/*
 * Copyright © 2026 Qiantong Technology Co., Ltd.
 * qModel Model Platform(Open Source Edition)
 *  *
 * License:
 * Released under the Apache License, Version 2.0.
 * You may use, modify, and distribute this software for commercial purposes
 * under the terms of the License.
 *  *
 * Special Notice:
 * All derivative versions are strictly prohibited from modifying or removing
 * the default system logo and copyright information.
 * For brand customization, please apply for brand customization authorization via official channels.
 *  *
 * More information: https://qmodel.qiantong.tech/business.html
 *  *
 * ============================================================================
 *  *
 * 版权所有 © 2026 江苏千桐科技有限公司
 * qModel 模型平台（开源版）
 *  *
 * 许可协议：
 * 本项目基于 Apache License 2.0 开源协议发布，
 * 允许在遵守协议的前提下进行商用、修改和分发。
 *  *
 * 特别说明：
 * 所有衍生版本不得修改或移除系统默认的 LOGO 和版权信息；
 * 如需定制品牌，请通过官方渠道申请品牌定制授权。
 *  *
 * 更多信息请访问：https://qmodel.qiantong.tech/business.html
 */

package tech.qiantong.qmodel.common.core.text;

import tech.qiantong.qmodel.common.utils.StringUtils;

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;

/**
 * 字符集工具类
 *
 * @author anivia
 */
public class CharsetKit
{
    /** ISO-8859-1 */
    public static final String ISO_8859_1 = "ISO-8859-1";
    /** UTF-8 */
    public static final String UTF_8 = "UTF-8";
    /** GBK */
    public static final String GBK = "GBK";

    /** ISO-8859-1 */
    public static final Charset CHARSET_ISO_8859_1 = Charset.forName(ISO_8859_1);
    /** UTF-8 */
    public static final Charset CHARSET_UTF_8 = Charset.forName(UTF_8);
    /** GBK */
    public static final Charset CHARSET_GBK = Charset.forName(GBK);

    /**
     * 转换为Charset对象
     *
     * @param charset 字符集，为空则返回默认字符集
     * @return Charset
     */
    public static Charset charset(String charset)
    {
        return StringUtils.isEmpty(charset) ? Charset.defaultCharset() : Charset.forName(charset);
    }

    /**
     * 转换字符串的字符集编码
     *
     * @param source 字符串
     * @param srcCharset 源字符集，默认ISO-8859-1
     * @param destCharset 目标字符集，默认UTF-8
     * @return 转换后的字符集
     */
    public static String convert(String source, String srcCharset, String destCharset)
    {
        return convert(source, Charset.forName(srcCharset), Charset.forName(destCharset));
    }

    /**
     * 转换字符串的字符集编码
     *
     * @param source 字符串
     * @param srcCharset 源字符集，默认ISO-8859-1
     * @param destCharset 目标字符集，默认UTF-8
     * @return 转换后的字符集
     */
    public static String convert(String source, Charset srcCharset, Charset destCharset)
    {
        if (null == srcCharset)
        {
            srcCharset = StandardCharsets.ISO_8859_1;
        }

        if (null == destCharset)
        {
            destCharset = StandardCharsets.UTF_8;
        }

        if (StringUtils.isEmpty(source) || srcCharset.equals(destCharset))
        {
            return source;
        }
        return new String(source.getBytes(srcCharset), destCharset);
    }

    /**
     * @return 系统字符集编码
     */
    public static String systemCharset()
    {
        return Charset.defaultCharset().name();
    }
}
