package com.imyeyu.utils;

import com.imyeyu.java.TimiJava;
import com.imyeyu.java.bean.timi.TimiCode;
import com.imyeyu.java.bean.timi.TimiException;

import java.io.StringWriter;
import java.net.IDN;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
import java.util.Locale;
import java.util.Map;

/**
 * 编码操作
 *
 * @author 夜雨
 * @version 2021-02-13 10:59
 */
public class Encoder {

	/**
	 * Unicode 编码全角字符
	 *
	 * @param data 字符串
	 * @return 编码结果
	 */
	public static String unicode(String data) {
		StringWriter out = new StringWriter(data.length() * 2);
		for (int i = 0, l = data.length(); i < l; i++) {
			char c = data.charAt(i);
			String cHex = Integer.toHexString(c).toUpperCase(Locale.ENGLISH);

			if (0xFFF < c) {
				out.write("\\u" + cHex);
			} else if (0xFF < c) {
				out.write("\\u0" + cHex);
			} else if (0x7F < c) {
				out.write("\\u00" + cHex);
			} else if (c < 32) {
				switch (c) {
					case '\b' -> {
						out.write('\\');
						out.write('b');
					}
					case '\n' -> {
						out.write('\\');
						out.write('n');
					}
					case '\t' -> {
						out.write('\\');
						out.write('t');
					}
					case '\f' -> {
						out.write('\\');
						out.write('f');
					}
					case '\r' -> {
						out.write('\\');
						out.write('r');
					}
					default -> {
						if (0xF < c) {
							out.write("\\u00" + cHex);
						} else {
							out.write("\\u000" + cHex);
						}
					}
				}
			} else {
				switch (c) {
					case '\'' -> {
						out.write('\\');
						out.write('\'');
					}
					case '"' -> {
						out.write('\\');
						out.write('"');
					}
					case '\\' -> {
						out.write('\\');
						out.write('\\');
					}
					case '/' -> {
						out.write('\\');
						out.write('/');
					}
					default -> out.write(c);
				}
			}
		}
		return out.toString();
	}

	/**
	 * Base64 编码字符串
	 *
	 * @param data 字符串
	 * @return 编码结果
	 */
	public static String base64(String data) {
		return base64(data.getBytes(StandardCharsets.UTF_8));
	}

	/**
	 * Base64 编码字节数据
	 *
	 * @param bytes 字节数据
	 * @return 编码结果
	 */
	public static String base64(byte[] bytes) {
		return Base64.getEncoder().encodeToString(bytes);
	}

	/**
	 * 编码 URL 参数值。不要传整个链接，此方法只用于<u>参数值</u>的编码
	 *
	 * @param data URL 参数
	 * @return 编码结果
	 */
	public static String urlArg(String data) {
		return URLEncoder.encode(data, StandardCharsets.UTF_8);
	}

	/**
	 * 编码 URL 参数
	 *
	 * @param args URL 参数表
	 * @return 编码结果
	 */
	public static String urlArgs(Map<String, Object> args) {
		StringBuilder sb = new StringBuilder();
		for (Map.Entry<String, Object> param : args.entrySet()) {
			sb.append('&').append(param.getKey()).append('=').append(urlArg(param.getValue().toString()));
		}
		return sb.substring(1);
	}

	/**
	 * 编码 URL 链接，半角 "+" 号会使用 "%2B"
	 *
	 * @param urlStr URL 链接
	 * @return 编码结果
	 */
	public static String url(String urlStr) {
		if (TimiJava.isEmpty(urlStr)) {
			return "";
		}
		try {
			URL url = new URL(urlStr);
			URI uri = new URI(url.getProtocol(), url.getUserInfo(), IDN.toASCII(url.getHost()), url.getPort(), url.getPath(), url.getQuery(), url.getRef());
			return uri.toASCIIString().replace("+", "%2B");
		} catch (MalformedURLException | URISyntaxException e) {
			throw new TimiException(TimiCode.ERROR, e.getMessage());
		}
	}

	/**
	 * 字节数据转 16 进制字符串
	 *
	 * @param bytes 字节数据
	 * @return 16 进制字符串
	 */
	public static String hex(byte[] bytes) {
		final int l = bytes.length;
		final char[] c = new char[l << 1];
		for (int i = 0, j = 0; i < l; i++) {
			c[j++] = Text.HEX_DIGITS_LOWER[(0xF0 & bytes[i]) >>> 4];
			c[j++] = Text.HEX_DIGITS_LOWER[0x0F & bytes[i]];
		}
		return new String(c);
	}
}