using ICSharpCode.SharpZipLib.Zip;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace XYY.Common.Standard
{
    public static class ZipHelper
    {
        /// <summary>
        /// 功能：压缩文件（暂时只压缩文件夹下一级目录中的文件，文件夹及其子级被忽略）
        /// </summary>
        /// <param name="dirPath">被压缩的文件夹夹路径</param>
        /// <param name="zipFilePath">生成压缩文件的路径，为空则默认与被压缩文件夹同一级目录，名称为：文件夹名+.zip</param>
        /// <param name="err">出错信息</param>
        /// <returns>是否压缩成功</returns>
        public static void ZipPath(string dirPath, string zipFilePath)
        {
            if (dirPath == string.Empty)
            {
                throw new Exception("要压缩的文件夹不能为空！");
            }
            if (!Directory.Exists(dirPath))
            {
                throw new Exception("要压缩的文件夹不存在！");
            }
            //压缩文件名为空时使用文件夹名＋.zip
            if (zipFilePath == string.Empty)
            {
                if (dirPath.EndsWith("\\"))
                {
                    dirPath = dirPath.Substring(0, dirPath.Length - 1);
                }
                zipFilePath = dirPath + ".zip";
            }

            try
            {
                string[] filenames = Directory.GetFiles(dirPath);
                using (ZipOutputStream s = new ZipOutputStream(File.Create(zipFilePath)))
                {
                    s.SetLevel(9);
                    byte[] buffer = new byte[4096];
                    foreach (string file in filenames)
                    {
                        ZipEntry entry = new ZipEntry(Path.GetFileName(file));
                        entry.DateTime = DateTime.Now;
                        s.PutNextEntry(entry);
                        using (FileStream fs = File.OpenRead(file))
                        {
                            int sourceBytes;
                            do
                            {
                                sourceBytes = fs.Read(buffer, 0, buffer.Length);
                                s.Write(buffer, 0, sourceBytes);
                            } while (sourceBytes > 0);
                        }
                    }
                    s.Finish();
                    s.Close();
                }
            }
            catch
            {
                throw;
            }
        }
        /// <summary>
        /// 重载一个方法
        /// </summary>
        /// <param name="dirPath"></param>
        /// <param name="zipFilePath"></param>
        /// <param name="filtration">过滤 指定后缀数据</param>
        /// <param name="maxSize">限制大小 byte 1m=1024*1024 1kb=1024b 根据单个文件大小，进行模糊设置</param>
        /// <exception cref="Exception"></exception>
        public static List<string> ZipPath(string dirPath, string zipFilePath, string filtration, int maxSize)
        {
            if (dirPath == string.Empty)
            {
                throw new Exception("要压缩的文件夹不能为空！");
            }
            if (!Directory.Exists(dirPath))
            {
                throw new Exception("要压缩的文件夹不存在！");
            }
            //压缩文件名为空时使用文件夹名＋.zip
            if (zipFilePath == string.Empty)
            {
                if (dirPath.EndsWith("\\"))
                {
                    dirPath = dirPath.Substring(0, dirPath.Length - 1);
                }
                zipFilePath = dirPath + ".zip";
            }
            List<string> zips = new List<string>();
            try
            {
                List<string> filenames = Directory.GetFiles(dirPath).ToList();
                int allFileNames = filenames.Count;
                List<string> tempFile = new List<string>();
                int count = 0;
                do
                {
                    if (tempFile.Count > 0) { filenames.RemoveAll(x => tempFile.Contains(x)); tempFile.Clear(); }
                    count++;
                    string rootPath = zipFilePath.Substring(0, zipFilePath.LastIndexOf(@"\") + 1);
                    string filePath = zipFilePath.Substring(zipFilePath.LastIndexOf(@"\") + 1, zipFilePath.Length - zipFilePath.LastIndexOf(@"\") - 1);
                    zipFilePath = rootPath + filePath.Split(".")[0].Split("-")[0] + $"-{count}" + ".zip";
                    zips.Add(zipFilePath);
                    using (ZipOutputStream s = new ZipOutputStream(File.Create(zipFilePath)))
                    {
                        s.SetLevel(9);
                        byte[] buffer = new byte[4096];
                        int totalLength = 0;
                        foreach (string file in filenames)
                        {
                            if (!string.IsNullOrEmpty(filtration)) { if (file.Contains(filtration)) { continue; } } //过滤文件
                            ZipEntry entry = new ZipEntry(Path.GetFileName(file));
                            entry.DateTime = DateTime.Now;
                            s.PutNextEntry(entry);
                            using (FileStream fs = File.OpenRead(file))
                            {
                                int sourceBytes;
                                do
                                {
                                    sourceBytes = fs.Read(buffer, 0, buffer.Length);
                                    totalLength += sourceBytes;
                                    if (totalLength > maxSize) { break; }
                                    s.Write(buffer, 0, sourceBytes);
                                } while (sourceBytes > 0);
                            }
                            //跳出循环
                            if (totalLength > maxSize) { break; }
                            allFileNames--;
                            tempFile.Add(file);
                        }
                        s.Finish();
                        s.Close();
                    }
                } while (allFileNames > 0);
                return zips;
            }
            catch
            {
                throw;
            }
        }

        /// <summary>
        /// 功能：解压zip格式的文件。
        /// </summary>
        /// <param name="zipFilePath">压缩文件路径</param>
        /// <param name="unZipDir">解压文件存放路径,为空时默认与压缩文件同一级目录下，跟压缩文件同名的文件夹</param>
        /// <param name="err">出错信息</param>
        /// <returns>解压是否成功</returns>
        public static void UnZipPath(string zipFilePath, string unZipDir)
        {
            if (zipFilePath == string.Empty)
            {
                throw new Exception("压缩文件不能为空！");
            }
            if (!File.Exists(zipFilePath))
            {
                throw new Exception("压缩文件不存在！");
            }
            //解压文件夹为空时默认与压缩文件同一级目录下，跟压缩文件同名的文件夹
            if (unZipDir == string.Empty)
                unZipDir = zipFilePath.Replace(Path.GetFileName(zipFilePath), Path.GetFileNameWithoutExtension(zipFilePath));
            if (!unZipDir.EndsWith("\\"))
                unZipDir += "\\";
            if (!Directory.Exists(unZipDir))
                Directory.CreateDirectory(unZipDir);

            try
            {
                using (ZipInputStream s = new ZipInputStream(File.OpenRead(zipFilePath)))
                {

                    ZipEntry theEntry;
                    while ((theEntry = s.GetNextEntry()) != null)
                    {
                        string directoryName = Path.GetDirectoryName(theEntry.Name);
                        string fileName = Path.GetFileName(theEntry.Name);
                        if (directoryName.Length > 0)
                        {
                            Directory.CreateDirectory(unZipDir + directoryName);
                        }
                        if (!directoryName.EndsWith("\\"))
                            directoryName += "\\";
                        if (fileName != string.Empty)
                        {
                            using (FileStream streamWriter = File.Create(unZipDir + theEntry.Name))
                            {

                                int size = 2048;
                                byte[] data = new byte[2048];
                                while (true)
                                {
                                    size = s.Read(data, 0, data.Length);
                                    if (size > 0)
                                    {
                                        streamWriter.Write(data, 0, size);
                                    }
                                    else
                                    {
                                        break;
                                    }
                                }
                            }
                        }
                    }//while
                }
            }
            catch
            {
                throw;
            }
        }


        public static Stream ZipStream(IEnumerable<ZipItem> streams)
        {
            MemoryStream ms = new MemoryStream();

            ZipOutputStream s = new ZipOutputStream(ms);
            s.SetLevel(9);
            byte[] buffer = new byte[4096];
            foreach (var item in streams)
            {
                ZipEntry entry = new ZipEntry(item.FileName);
                entry.DateTime = DateTime.Now;
                s.PutNextEntry(entry);
                int sourceBytes;
                do
                {
                    sourceBytes = item.Stream.Read(buffer, 0, buffer.Length);
                    s.Write(buffer, 0, sourceBytes);
                } while (sourceBytes > 0);
            }
            s.Finish();
            ms.Position = 0;
            return ms;
        }




        //public static Stream WriteZip(params ZipItem[] streams)
        //{

        //    MemoryStream ms = new MemoryStream();
        //    ZipOutputStream zipOut = null; // 定义压缩输出流 
        //    zipOut = new ZipOutputStream(ms); // 实例化压缩输出流对象，并指定压缩文件的输出路径    

        //    for (int i = 0; i < streams.Length; i++)
        //    {
        //        zipOut.PutNextEntry(new ZipEntry(streams[i].FileName));   // 创建ZipEntry  每一个被压缩的文件都用ZipEntry表示，需要为每一个压缩后的文件设置名称  
        //        zipOut.SetComment("这里是注释");  // 设置注释   

        //        Stream fs = streams[i].Stream;//file.OpenRead();//定义输出流
        //        long dataLengthToRead = fs.Length; ////获取输出流总大小                           

        //        while (dataLengthToRead > 0)
        //        {   // 读取内容 
        //            byte[] buffer = new byte[524288];
        //            int lengthRead = fs.Read(buffer, 0, buffer.Length);//读取的大小
        //            zipOut.Write(buffer, 0, lengthRead); // 压缩输出内容                
        //            dataLengthToRead = dataLengthToRead - lengthRead;
        //        }
        //        fs.Close();  // 关闭输入流   
        //    }

        //    zipOut.Finish();  //完成压缩流          
        //    //zipOut.Close(); // 关闭压缩输出流                         
        //    ms.Position = 0;
        //    return ms;
        //}
    }
    public class ZipItem
    {
        public ZipItem(string fileName, Stream stream)
        {
            this.FileName = fileName;
            this.Stream = stream;

        }

        public string FileName
        {
            get;
            set;
        }
        public Stream Stream
        {
            get;
            set;
        }
    }
}