package com.whyc;


import com.whyc.util.*;
import com.whyc.util.*;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.InputStream;

/**
 * java class解密
 *
 * @author perry
 */
public class JarDecryptor {
    //单例
    private static final JarDecryptor single = new JarDecryptor();
    //机器码
    private char[] code;
    //加密后文件存放位置
    private static final String ENCRYPT_PATH = "META-INF/" + Const.FILE_NAME + "/";

    //加密后文件存放位置
    private static final String DESCRIPTION_PATH = "META-INF/";

    /**
     * 单例
     *
     * @return 单例
     */
    public static JarDecryptor getInstance() {
        return single;
    }

    /**
     * 构造
     */
    public JarDecryptor() {
        this.code = SysUtils.makeMarchinCode();
    }

    /**
     * 根据名称解密出一个文件
     *
     * @param projectPath 项目所在的路径
     * @param fileName    文件名
     * @param password    密码
     * @return 解密后的字节
     */
    public byte[] doDecrypt(String projectPath, String fileName, char[] password) {
        long t1 = System.currentTimeMillis();
        File workDir = new File(projectPath);
        byte[] bytes = readEncryptedFile(workDir, fileName);
        if (bytes == null) {
            return null;
        }

        //读取机器码，有机器码，先用机器码解密
        byte[] codeBytes = readEncryptedFile(workDir, Const.CONFIG_CODE);
        if (codeBytes != null) {
            //本机器码和打包的机器码不匹配
            if (!StrUtils.equal(EncryptUtils.md5(this.code), StrUtils.toChars(codeBytes))) {
                Log.println("该项目不可在此机器上运行!\n");
                System.exit(-1);
            }

            //用机器码解密
            char[] pass = StrUtils.merger(fileName.toCharArray(), code);
            bytes = EncryptUtils.de(bytes, pass, Const.ENCRYPT_TYPE);
        }

        //无密码启动,读取隐藏的密码
        if (password.length == 1 && password[0] == '#') {
            password = readPassFromJar(workDir);
        }

        //密码解密
        char[] pass = StrUtils.merger(password, fileName.toCharArray());
        bytes = EncryptUtils.de(bytes, pass, Const.ENCRYPT_TYPE);

        long t2 = System.currentTimeMillis();
        Log.debug("解密: " + fileName + " (" + (t2 - t1) + " ms)");

        return bytes;

    }

    /**
     * 在jar文件或目录中读取文件字节
     *
     * @param workDir jar文件或目录
     * @param name    文件名
     * @return 文件字节数组
     */
    public static byte[] readEncryptedFile(File workDir, String name) {
        byte[] bytes = null;
        String fileName = ENCRYPT_PATH + name;
        //jar文件
        if (workDir.isFile()) {
            bytes = JarUtils.getFileFromJar(workDir, fileName);
        } else {//war解压的目录
            File file = new File(workDir, fileName);
            if (file.exists()) {
                bytes = IoUtils.readFileToByte(file);
            }
        }
        return bytes;
    }

    /**
     * 在jar文件或目录中读取密码字节
     *
     * @param workDir jar文件或目录
     * @param name    文件名
     * @return 文件字节数组
     */
    public static byte[] readEncryptedFile2(File workDir, String name) {
        byte[] bytes = null;
        String fileName = DESCRIPTION_PATH + name;
        //jar文件
        if (workDir.isFile()) {
            bytes = JarUtils.getFileFromJar(workDir, fileName);
        } else {//war解压的目录
            File file = new File(workDir, fileName);
            if (file.exists()) {
                bytes = IoUtils.readFileToByte(file);
            }
        }
        return bytes;
    }

    /**
     * 读取隐藏在jar的密码
     *
     * @param workDir jar路径
     * @return 密码char
     */
    public static char[] readPassFromJar(File workDir) {
        byte[] passbyte = readEncryptedFile(workDir, Const.CONFIG_PASS);
        if (passbyte != null) {
            char[] pass = StrUtils.toChars(passbyte);
            return EncryptUtils.md5(pass);
        }
        return null;
    }

    /**
     * 读取隐藏在jar的密码
     *
     * @param workDir jar路径
     * @return 密码char
     */
    public static char[] readPassFromJar2(File workDir) {
        byte[] passbyte = readEncryptedFile2(workDir, Const.FILE_NAME2);
        if (passbyte != null) {
            char[] pass = StrUtils.toChars(passbyte);
            return EncryptUtils.md5(pass);
        }
        return null;
    }

    /**
     * 解密配置文件，spring读取文件时调用
     *
     * @param path 配置文件路径
     * @param in   输入流
     * @return 解密的输入流
     */
    public InputStream decryptConfigFile(String path, InputStream in, char[] pass) {
        if (path.endsWith(".class")) {
            return in;
        }
        String projectPath = JarUtils.getRootPath(null);
        if (StrUtils.isEmpty(projectPath)) {
            return in;
        }
        byte[] bytes = null;
        try {
            bytes = IoUtils.toBytes(in);
        } catch (Exception e) {

        }
        if (bytes == null || bytes.length == 0) {//需要解密
            bytes = this.doDecrypt(projectPath, path, pass);
        }
        if (bytes == null) {
            return in;
        }
        in = new ByteArrayInputStream(bytes);
        return in;
    }

}