package com.yougou.h5center.diff;

/**
 * @author long.yl.
 * @Date 2016/6/1
 */
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.zip.CRC32;
import java.util.zip.CheckedOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class ZipCompressor {
    protected static final Logger LOGGER = LoggerFactory.getLogger(ZipCompressor.class);

    static final int BUFFER = 8192;

    private File zipFile;

    public ZipCompressor(File zipFile) {
        this.zipFile = zipFile;
    }

    public void compress(File indir) {
        try {
            FileOutputStream fileOutputStream = new FileOutputStream(zipFile);
            CheckedOutputStream cos = new CheckedOutputStream(fileOutputStream,
                    new CRC32());
            ZipOutputStream out = new ZipOutputStream(cos);
            String basedir = "";
            compress(indir, out, basedir);
            out.close();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    private void compress(File file, ZipOutputStream out, String basedir) {
        /* 判断是目录还是文件 */
        if (file.isDirectory()) {
            LOGGER.info("压缩：" + basedir + file.getName());
            this.compressDirectory(file, out, basedir);
        } else {
            LOGGER.info("压缩：" + basedir + file.getName());
            this.compressFile(file, out, basedir);
        }
    }

    /** 压缩一个目录 */
    private void compressDirectory(File dir, ZipOutputStream out, String basedir) {
        if (!dir.exists())
            return;

        File[] files = dir.listFiles();
        for (int i = 0; i < files.length; i++) {
            /* 递归 */
            compress(files[i], out, basedir + dir.getName() + "/");
        }
    }

    /** 压缩一个文件 */
    private void compressFile(File file, ZipOutputStream out, String basedir) {
        if (!file.exists()) {
            return;
        }
        try {
            BufferedInputStream bis = new BufferedInputStream(
                    new FileInputStream(file));
            ZipEntry entry = new ZipEntry(basedir + file.getName());
            out.putNextEntry(entry);
            int count;
            byte data[] = new byte[BUFFER];
            while ((count = bis.read(data, 0, BUFFER)) != -1) {
                out.write(data, 0, count);
            }
            bis.close();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}
