import jp.hishidama.zip.ZipCloak;
import jp.hishidama.zip.ZipEntry;
import jp.hishidama.zip.ZipFile;
import java.io.File;
import java.nio.charset.Charset;
import java.io.UnsupportedEncodingException;

import java.util.*;
import java.io.*;


class ZipDecrypt {
	static byte begin = '!'; // 対象文字列の始まり
	static byte end = '~';   // 対象文字列の終わり
	static int MaxPwLength=5; // 探索するパスワードの長さ

	//public static String bruteforce(ZipCloak zip, File dst) {
	public static String bruteforce(File src, File dst) throws Exception{
		System.out.println("bruteforce called");

		for(int pwlength=1; pwlength<=MaxPwLength; pwlength++) {

			// 文字数が変わったら作り直す
			byte[] passwd = new byte[pwlength];
			for(int i=0; i<pwlength; i++) { passwd[i] = begin; }

			boolean carry = false;

			// 組み合わせの数だけ実行
			for(int j=0; j<Math.pow((end-begin+1),pwlength); j++){
				//if(challange(zip, dst, passwd)) {
					System.out.println("***TRYING*** " + new String(passwd,0,pwlength));
				if(challange(src,passwd)) {
					System.out.println("***SUCCESS*** Password found: " + new String(passwd,0,pwlength));
					return new String(passwd, 0, pwlength);
				} else {
				}

				passwd[pwlength-1]++;
				for(int i=pwlength-1; i >= 0; i--) {
					if(passwd[i] == end+1) { 
						passwd[i] = begin;
						if(i > 0) { passwd[i-1]++; }
						carry = true;
					} else {
						carry = false;
					}
				}
			}
		}

		return "";
	}

	public static boolean challange(ZipCloak zip, File dst, byte[] pw) {
		try {
			//System.out.println("Trying '" + new String(pw, 0, pw.length) + "'...");
			zip.decrypt(dst, pw);
		} catch (java.util.zip.ZipException e) {
			return false;
		} catch (java.io.IOException e) {
			System.out.println("IOException!!!");
			return false;
		}

		return true;
	}
/*
	public static boolean challange(File src, byte[] pw) {
		try {
			ZipFile zf = new ZipFile(src);
			zf.setPassword(pw);
			zf.setCheckCrc(true);
			for(Iterator<ZipEntry> i=zf.getEntriesIterator(); i.hasNext();) {
				ZipEntry ze = i.next();
				InputStream is = zf.getInputStream(ze); 
				for(;;) {
					int c = is.read();
					if (c == -1) break;
				}
				System.out.println("***DEBUG*** Trying.. " + new String(pw,0,pw.length));
			}
			zf.close();
		} catch (jp.hishidama.zip.ZipPasswordException e) {
			return false;
		} catch (jp.hishidama.zip.ZipCrcException e) {
			return false;
		} catch (java.util.zip.ZipException e) {
			return false;
		} catch (java.io.IOException e) {
			return false;
	/	} catch (Exception e) {
			return false;
		}
		return true;
	}*/

	public static boolean challange(File src, byte[] pw) throws Exception{
		ZipFile zf = null;
		//InputStream is = new InputStream();

		try {
			zf = new ZipFile(src);
			zf.setPassword(pw);
			zf.setCheckCrc(true);
			for(Iterator<ZipEntry> i=zf.getEntriesIterator(); i.hasNext();) {
				ZipEntry ze = i.next();
				InputStream is = zf.getInputStream(ze); 
				ByteArrayOutputStream bos = new ByteArrayOutputStream();
				for(;;) {
				  int c = is.read();
					if (c == -1) break;
					bos.write(c);
				}
				System.out.println("***DEBUG*** Trying.. " + new String(pw,0,pw.length));
			}
		} catch (jp.hishidama.zip.ZipPasswordException e) {
			return false;
		} catch (jp.hishidama.zip.ZipCrcException e) {
			return false;
		} catch (java.util.zip.ZipException e) {
			return false;
		//} catch (java.io.IOException e) {
		//	return false;
		} catch (Exception e) {
			//System.out.println(new String(pw,0,pw.length));
			e.printStackTrace();
			return false;
		} finally {
			//if (is != null) is.close();
			if (zf != null) zf.close();
		}
		return true;
	}
	public static void main(String[] args) throws Exception {
		File src = new File(args[0]);
		File dst = new File(args[1]);

		ZipCloak zip = new ZipCloak(src);
		
		//System.out.println(bruteforce(zip,dst));
		System.out.println(bruteforce(src,dst));
	}
}