using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace BaseLibRWFile
{
    /// <summary>
    /// AES加密解密
    /// </summary>

    public class AES
    {

        #region 加密

        #region 加密字符串

        /// <summary>

        /// AES 加密(高级加密标准，是下一代的加密算法标准，速度快，安全级别高，目前 AES 标准的一个实现是 Rijndael 算法)

        /// </summary>

        /// <param name="EncryptString">待加密密文</param>

        /// <param name="EncryptKey">加密密钥</param>

        public static string AESEncrypt(string EncryptString, string EncryptKey)
        {
            return Convert.ToBase64String(AESEncrypt(Encoding.Default.GetBytes(EncryptString), EncryptKey));
        }
        #endregion
        #region 加密字节数组
        /// <summary>
        /// AES 加密(高级加密标准，是下一代的加密算法标准，速度快，安全级别高，目前 AES 标准的一个实现是 Rijndael 算法)
        /// </summary>
        /// <param name="EncryptString">待加密密文</param>

        /// <param name="EncryptKey">加密密钥</param>

        public static byte[] AESEncrypt(byte[] EncryptByte, string EncryptKey)

        {

            if (EncryptByte.Length == 0) { throw (new Exception("明文不得为空")); }

            if (string.IsNullOrEmpty(EncryptKey)) { throw (new Exception("密钥不得为空")); }

            byte[] m_strEncrypt;

            byte[] m_btIV = Convert.FromBase64String("Rkb4jvUy/ye7Cd7k89QQgQ==");

            byte[] m_salt = Convert.FromBase64String("gsf4jvkyhye5/d7k8OrLgM==");

            Rijndael m_AESProvider = Rijndael.Create();

            try

            {

                MemoryStream m_stream = new MemoryStream();

                PasswordDeriveBytes pdb = new PasswordDeriveBytes(EncryptKey, m_salt);

                ICryptoTransform transform = m_AESProvider.CreateEncryptor(pdb.GetBytes(32), m_btIV);

                CryptoStream m_csstream = new CryptoStream(m_stream, transform, CryptoStreamMode.Write);

                m_csstream.Write(EncryptByte, 0, EncryptByte.Length);

                m_csstream.FlushFinalBlock();

                m_strEncrypt = m_stream.ToArray();

                m_stream.Close(); m_stream.Dispose();

                m_csstream.Close(); m_csstream.Dispose();

            }

            catch (IOException ex) { throw ex; }

            catch (CryptographicException ex) { throw ex; }

            catch (ArgumentException ex) { throw ex; }

            catch (Exception ex) { throw ex; }

            finally { m_AESProvider.Clear(); }

            return m_strEncrypt;

        }

        #endregion

        #endregion
        #region 解密

        #region 解密字符串

        /// <summary>

        /// AES 解密(高级加密标准，是下一代的加密算法标准，速度快，安全级别高，目前 AES 标准的一个实现是 Rijndael 算法)

        /// </summary>

        /// <param name="DecryptString">待解密密文</param>

        /// <param name="DecryptKey">解密密钥</param>

        public static string AESDecrypt(string DecryptString, string DecryptKey)
        {
            return Convert.ToBase64String(AESDecrypt(Encoding.Default.GetBytes(DecryptString), DecryptKey));
        }

        #endregion
        #region 解密字节数组

        /// <summary>

        /// AES 解密(高级加密标准，是下一代的加密算法标准，速度快，安全级别高，目前 AES 标准的一个实现是 Rijndael 算法)

        /// </summary>

        /// <param name="DecryptString">待解密密文</param>

        /// <param name="DecryptKey">解密密钥</param>

        public static byte[] AESDecrypt(byte[] DecryptByte, string DecryptKey)

        {

            if (DecryptByte.Length == 0) { throw (new Exception("密文不得为空")); }

            if (string.IsNullOrEmpty(DecryptKey)) { throw (new Exception("密钥不得为空")); }

            byte[] m_strDecrypt;

            byte[] m_btIV = Convert.FromBase64String("Rkb4jvUy/ye7Cd7k89QQgQ==");

            byte[] m_salt = Convert.FromBase64String("gsf4jvkyhye5/d7k8OrLgM==");

            Rijndael m_AESProvider = Rijndael.Create();

            try

            {

                MemoryStream m_stream = new MemoryStream();

                PasswordDeriveBytes pdb = new PasswordDeriveBytes(DecryptKey, m_salt);

                ICryptoTransform transform = m_AESProvider.CreateDecryptor(pdb.GetBytes(32), m_btIV);

                CryptoStream m_csstream = new CryptoStream(m_stream, transform, CryptoStreamMode.Write);

                m_csstream.Write(DecryptByte, 0, DecryptByte.Length);

                m_csstream.FlushFinalBlock();

                m_strDecrypt = m_stream.ToArray();

                m_stream.Close(); m_stream.Dispose();

                m_csstream.Close(); m_csstream.Dispose();

            }

            catch (IOException ex) { throw ex; }

            catch (CryptographicException ex) { throw ex; }

            catch (ArgumentException ex) { throw ex; }

            catch (Exception ex) { throw ex; }

            finally { m_AESProvider.Clear(); }

            return m_strDecrypt;

        }

        #endregion

        #endregion
    }



    /// <summary>

    /// 文件加密类

    /// </summary>

    public class FileEncrypt

    {

        #region 变量

        /// <summary>

        /// 一次处理的明文字节数

        /// </summary>

        public static readonly int encryptSize = 10000000;

        /// <summary>

        /// 一次处理的密文字节数

        /// </summary>

        public static readonly int decryptSize = 10000016;

        #endregion
        #region 加密文件

        /// <summary>

        /// 加密文件

        /// </summary>

        public static void EncryptFile(string path, string pwd)
        {

            try

            {

                if (File.Exists(path + ".temp")) File.Delete(path + ".temp");

                using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))

                {

                    if (fs.Length > 0)

                    {

                        using (FileStream fsnew = new FileStream(path + ".temp", FileMode.OpenOrCreate, FileAccess.Write))

                        {

                            if (File.Exists(path + ".temp")) File.SetAttributes(path + ".temp", FileAttributes.Hidden);

                            int blockCount = ((int)fs.Length - 1) / encryptSize + 1;

                            for (int i = 0; i < blockCount; i++)

                            {

                                int size = encryptSize;

                                if (i == blockCount - 1) size = (int)(fs.Length - i * encryptSize);

                                byte[] bArr = new byte[size];

                                fs.Read(bArr, 0, size);

                                byte[] result = AES.AESEncrypt(bArr, pwd);

                                fsnew.Write(result, 0, result.Length);

                                fsnew.Flush();

                                //refreshFileProgress(blockCount, i + 1); //更新进度

                            }

                            fsnew.Close();

                            fsnew.Dispose();

                        }

                        fs.Close();

                        fs.Dispose();

                        FileAttributes fileAttr = File.GetAttributes(path);

                        File.SetAttributes(path, FileAttributes.Archive);

                        File.Delete(path);

                        File.Move(path + ".temp", path);

                        File.SetAttributes(path, fileAttr);

                    }

                }

            }

            catch (Exception ex)

            {

                File.Delete(path + ".temp");

                throw ex;

            }

        }

        #endregion
        #region 解密文件

        /// <summary>

        /// 解密文件

        /// </summary>

        public static void DecryptFile(string path, string pwd)

        {

            try

            {

                if (File.Exists(path + ".temp")) File.Delete(path + ".temp");

                using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))

                {

                    if (fs.Length > 0)

                    {

                        using (FileStream fsnew = new FileStream(path + ".temp", FileMode.OpenOrCreate, FileAccess.Write))

                        {

                            if (File.Exists(path + ".temp")) File.SetAttributes(path + ".temp", FileAttributes.Hidden);

                            int blockCount = ((int)fs.Length - 1) / decryptSize + 1;

                            for (int i = 0; i < blockCount; i++)

                            {

                                int size = decryptSize;

                                if (i == blockCount - 1) size = (int)(fs.Length - i * decryptSize);

                                byte[] bArr = new byte[size];

                                fs.Read(bArr, 0, size);

                                byte[] result = AES.AESDecrypt(bArr, pwd);

                                fsnew.Write(result, 0, result.Length);

                                fsnew.Flush();

                                //refreshFileProgress(blockCount, i + 1); //更新进度

                            }

                            fsnew.Close();

                            fsnew.Dispose();

                        }

                        fs.Close();

                        fs.Dispose();

                        FileAttributes fileAttr = File.GetAttributes(path);

                        File.SetAttributes(path, FileAttributes.Archive);

                        File.Delete(path);

                        File.Move(path + ".temp", path);

                        File.SetAttributes(path, fileAttr);

                    }

                }

            }

            catch (Exception ex)

            {

                File.Delete(path + ".temp");

                throw ex;

            }

        }

        #endregion
    }
    /// <summary>

    /// 更新文件加密进度

    /// </summary>

    public delegate void RefreshFileProgress(int max, int value);




    /// <summary>

    /// 文件夹加密类

    /// </summary>

    public class DirectoryEncrypt

    {

        #region 加密文件夹及其子文件夹中的所有文件

        /// <summary>

        /// 加密文件夹及其子文件夹中的所有文件

        /// </summary>

        public static void EncryptDirectory(string dirPath, string pwd, RefreshDirProgress refreshDirProgress, RefreshFileProgress refreshFileProgress)

        {

            string[] filePaths = Directory.GetFiles(dirPath, "*", SearchOption.AllDirectories);

            for (int i = 0; i < filePaths.Length; i++)

            {

                FileEncrypt.EncryptFile(filePaths[i], pwd);

                refreshDirProgress(filePaths.Length, i + 1);

            }

        }

        #endregion
        #region 解密文件夹及其子文件夹中的所有文件

        /// <summary>

        /// 解密文件夹及其子文件夹中的所有文件

        /// </summary>

        public static void DecryptDirectory(string dirPath, string pwd, RefreshDirProgress refreshDirProgress, RefreshFileProgress refreshFileProgress)

        {

            string[] filePaths = Directory.GetFiles(dirPath, "*", SearchOption.AllDirectories);

            for (int i = 0; i < filePaths.Length; i++)

            {

                FileEncrypt.DecryptFile(filePaths[i], pwd);

                refreshDirProgress(filePaths.Length, i + 1);

            }

        }

        #endregion
    }
    /// <summary>

    /// 更新文件夹加密进度

    /// </summary>

    public delegate void RefreshDirProgress(int max, int value);




}