using ICSharpCode.SharpZipLib.Checksum;
using ICSharpCode.SharpZipLib.Zip;
using System.Text;

namespace YLErp.Helpers
{
    public static class ZipHelper
    {
        static ZipHelper()
        {
            Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
            ZipStrings.CodePage = Encoding.GetEncoding("gb2312").CodePage;
        }

        /// <summary>
        /// 压缩文件目录
        /// </summary>
        /// <param name="sourceDir"></param>
        /// <param name="targetZipFile"></param>
        public static void ZipDirectory(string sourceDir, string targetZipFile)
        {
            if (sourceDir[sourceDir.Length - 1] != Path.DirectorySeparatorChar)
            {
                sourceDir += Path.DirectorySeparatorChar;
            }
            var outstream = new ZipOutputStream(File.Create(targetZipFile));
            outstream.SetLevel(6);
            ZipDirectory(sourceDir, outstream, sourceDir);
            outstream.Finish();
            outstream.Close();
        }

        /// <summary>
        /// 压缩文件目录
        /// </summary>
        /// <param name="sourceDir"></param>
        /// <param name="outStream"></param>
        /// <param name="staticFile"></param>
        public static void ZipDirectory(string sourceDir, ZipOutputStream outStream, string staticFile)
        {
            if (sourceDir[sourceDir.Length - 1] != Path.DirectorySeparatorChar)
            {
                sourceDir += Path.DirectorySeparatorChar;
            }

            //获取指定目录下所有文件和子目录文件名称
            var filenames = Directory.GetFileSystemEntries(sourceDir);

            zip(filenames, outStream, staticFile);
        }

        public static void zipFile(string strFile, string strZip)
        {
            var len = strFile.Length;
            var strlen = strFile[len - 1];
            if (strFile[strFile.Length - 1] != Path.DirectorySeparatorChar)
            {
                strFile += Path.DirectorySeparatorChar;
            }
            var outstream = new ZipOutputStream(File.Create(strZip));
            outstream.SetLevel(6);
            zip(strFile, outstream, strFile);
            outstream.Finish();
            outstream.Close();
        }

        public static void zipOnlyFile(string strFile, string strZip, string password = "")
        {
            var outstream = new ZipOutputStream(File.Create(strZip));
            outstream.SetLevel(6);
            if (!string.IsNullOrWhiteSpace(password))
            {
                outstream.Password = password;
            }
            string[] filenames = new string[] { strFile };
            zip(filenames, outstream, strFile);
            outstream.Finish();
            outstream.Close();
        }

        public static void zip(string strFile, ZipOutputStream outstream, string staticFile)
        {
            if (strFile[strFile.Length - 1] != Path.DirectorySeparatorChar)
            {
                strFile += Path.DirectorySeparatorChar;
            }
            var crc = new Crc32();
            //获取指定目录下所有文件和子目录文件名称
            string[] filenames = Directory.GetFileSystemEntries(strFile);
            zip(filenames, outstream, staticFile);
        }

        public static void zipFiles(string[] filenames, string parentDirectory, out byte[] buffer)
        {
            var stream = new MemoryStream();
            var outstream = new ZipOutputStream(stream);
            outstream.SetLevel(6);
            zip(filenames, outstream, parentDirectory);
            outstream.Finish();
            stream.Seek(0, SeekOrigin.Begin);
            buffer = new byte[stream.Length];
            stream.Read(buffer, 0, buffer.Length);
            outstream.Close();
        }

        /// <summary>
        /// 压缩多个文件
        /// </summary>
        /// <param name="sourceFiles">要进行压缩的文件集合</param>
        /// <param name="targetZipFile">压缩目标文件</param>
        public static void ZipFilesWithLevel(List<string> sourceFiles, string targetZipFile, int compressionLevel)
        {
            foreach (var fileToZip in sourceFiles)
            {
                //如果文件没有找到，则报错
                if (!File.Exists(fileToZip))
                {
                    throw new FileNotFoundException("指定要压缩的文件: " + fileToZip + " 不存在!");
                }
            }

            using var ZipFile = File.Create(targetZipFile);
            using var ZipStream = new ZipOutputStream(ZipFile);
            foreach (var fileToZip in sourceFiles)
            {
                var fileName = fileToZip.Substring(fileToZip.LastIndexOf(Path.DirectorySeparatorChar));

                using var fs = File.OpenRead(fileToZip);
                var buffer = new byte[fs.Length];
                fs.Read(buffer, 0, buffer.Length);
                fs.Close();

                var ZipEntry = new ZipEntry(fileName);
                ZipStream.PutNextEntry(ZipEntry);
                ZipStream.SetLevel(compressionLevel);

                ZipStream.Write(buffer, 0, buffer.Length);
            }
            ZipStream.Finish();
            ZipStream.Close();
        }

        private static void zip(string[] filenames, ZipOutputStream outstream, string staticFile)
        {
            var crc = new Crc32();
            //遍历文件
            foreach (var file in filenames)
            {
                if (Directory.Exists(file))
                {
                    zip(file, outstream, staticFile);
                }
                //否则，直接压缩文件
                else
                {
                    //打开文件
                    var fs = File.OpenRead(file);
                    //定义缓存区对象
                    var buffer = new byte[fs.Length];
                    //通过字符流，读取文件
                    fs.Read(buffer, 0, buffer.Length);
                    //得到目录下的文件（比如:D:\Debug1\test）,test
                    //这里是为了得到压缩文件内的目录结构;
                    string tempfile = file.Substring(staticFile.LastIndexOf(Path.DirectorySeparatorChar) + 1);
                    //string tempfile = Path.GetFileName(file);
                    ZipEntry entry = new ZipEntry(tempfile)
                    {
                        DateTime = DateTime.Now,
                        Size = fs.Length
                    };
                    fs.Close();
                    crc.Reset();
                    crc.Update(buffer);
                    entry.Crc = crc.Value;
                    outstream.PutNextEntry(entry);
                    //写文件
                    outstream.Write(buffer, 0, buffer.Length);
                }
            }
        }

        public static string unZipFile(string TargetFile, string fileDir, out string msg)
        {
            LogFactory.GetLogger("UploadEventReportFile").Info($"准备解压{fileDir}->{TargetFile}");
            msg = "";
            //读取压缩文件（zip文件），准备解压缩
            using (var inputstream = new ZipInputStream(File.OpenRead(TargetFile.Trim())))
            {
                ZipEntry entry;
                var pathName = Path.GetFileNameWithoutExtension(TargetFile);
                fileDir = Path.Combine(fileDir, pathName);
                LogFactory.GetLogger("UploadEventReportFile").Info($"准备解压{fileDir}");
                var path = fileDir;
                //压缩文件内第一层子目录
                var rootDir = "";
                //压缩文件内子目录
                var dir = "";
                var fileName = "";
                while ((entry = inputstream.GetNextEntry()) != null)
                {
                    if (!string.IsNullOrWhiteSpace(entry.Name))
                    {
                        //得到根目录下的第一级子文件夹的名称
                        rootDir = Path.GetDirectoryName(entry.Name);
                        if (rootDir.IndexOf(Path.DirectorySeparatorChar) >= 0)
                        {
                            rootDir = rootDir.Substring(0, rootDir.IndexOf(Path.DirectorySeparatorChar) + 1);
                        }
                        //得到根目录下的第一级子文件夹下的子文件夹名称
                        dir = Path.GetDirectoryName(entry.Name);
                        //根目录下的文件名称
                        fileName = Path.GetFileName(entry.Name);
                    }
                    LogFactory.GetLogger("UploadEventReportFile").Info($"根目录下的文件名称{fileName}");
                    //创建根目录下的子文件夹，不限制级别
                    if (!Directory.Exists(fileDir + Path.DirectorySeparatorChar + dir))
                    {
                        path = fileDir + Path.DirectorySeparatorChar + dir;
                        //在指定的路径创建文件夹
                        Directory.CreateDirectory(path);
                        LogFactory.GetLogger("UploadEventReportFile").Info($"在指定的路径创建文件夹{path}");
                    }
                    if (dir == "" && fileName != "")
                    {
                        //根目录下的文件
                        path = fileDir;
                    }
                    else if (dir != "" && fileName != "")
                    {
                        //根目录下的第一级子文件夹下的文件
                        if (dir.IndexOf(Path.DirectorySeparatorChar) > 0)
                        {
                            //指定文件保存路径
                            path = fileDir + Path.DirectorySeparatorChar + dir;
                            LogFactory.GetLogger("UploadEventReportFile").Info($"指定文件保存路径{path}");
                        }
                    }
                    if (dir == rootDir)
                    {
                        //判断是不是需要保存在根目录下的文件
                        path = fileDir + Path.DirectorySeparatorChar + rootDir;
                    }

                    //以下为解压zip文件的基本步骤
                    //基本思路：遍历压缩文件里的所有文件，创建一个相同的文件
                    if (fileName != string.Empty)
                    {
                        var fs = File.Create(path + Path.DirectorySeparatorChar + fileName);
                        LogFactory.GetLogger("UploadEventReportFile").Info($"遍历压缩文件里的所有文件{fs.Name}");
                        var size = 2048;
                        var data = new byte[2048];
                        while (true)
                        {
                            size = inputstream.Read(data, 0, data.Length);
                            if (size > 0)
                            {
                                fs.Write(data, 0, size);
                            }
                            else
                            {
                                break;
                            }
                        }
                        fs.Close();
                    }
                }
            }
            msg = "解压成功！";
            return fileDir;
        }
    }
}