using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace BackupAndImport
{
    class Tools
    {
        /// <summary>
        /// 获取指定目录中的匹配文件
        /// </summary>
        /// <param name="dir">要搜索的目录</param>
        /// <param name="regexPattern">文件名模式（正则）。null表示忽略模式匹配，返回所有文件</param>
        /// <param name="depth">递归深度。负数表示不限，0表示仅顶级</param>
        /// <param name="throwEx">是否抛异常</param>
        /// <returns></returns>GetFiles(path,"(?<db>(数据库.db)|(aliTools.db))",-1)
        public static string[] GetFiles(string dir, string regexPattern = null, int depth = 0, bool throwEx = false)
        {
            List<string> lst = new List<string>();

            try
            {
                foreach (string item in Directory.GetFileSystemEntries(dir))
                {
                    try
                    {
                        bool isFile = (File.GetAttributes(item) & FileAttributes.Directory) != FileAttributes.Directory;

                        if (isFile && (regexPattern == null || Regex.IsMatch(Path.GetFileName(item), regexPattern, RegexOptions.IgnoreCase | RegexOptions.Multiline)))
                        { lst.Add(item); }

                        //递归
                        if (depth != 0 && !isFile) { lst.AddRange(GetFiles(item, regexPattern, depth - 1, throwEx)); }
                    }
                    catch { if (throwEx) { throw; } }
                }
            }
            catch { if (throwEx) { throw; } }

            return lst.ToArray();
        }


        /// <summary>
        /// 序列化 对象到字符串
        /// </summary>
        /// <param name="obj">泛型对象</param>
        /// <returns>序列化后的字符串</returns>
        public static string Serialize<T>(T obj)
        {
            try
            {
                IFormatter formatter = new BinaryFormatter();
                MemoryStream stream = new MemoryStream();
                formatter.Serialize(stream, obj);
                stream.Position = 0;
                byte[] buffer = new byte[stream.Length];
                stream.Read(buffer, 0, buffer.Length);
                stream.Flush();
                stream.Close();
                return Convert.ToBase64String(buffer);
            }
            catch (Exception ex)
            {
                throw new Exception("序列化失败,原因:" + ex.Message);
            }
        }

        /// <summary>
        /// 反序列化 字符串到对象
        /// </summary>
        /// <param name="obj">泛型对象</param>
        /// <param name="str">要转换为对象的字符串</param>
        /// <returns>反序列化出来的对象</returns>
        public static T Desrialize<T>(T obj, string str)
        {
            try
            {
                obj = default(T);
                IFormatter formatter = new BinaryFormatter();
                byte[] buffer = Convert.FromBase64String(str);
                MemoryStream stream = new MemoryStream(buffer);
                obj = (T)formatter.Deserialize(stream);
                stream.Flush();
                stream.Close();
            }
            catch (Exception ex)
            {
                throw new Exception("反序列化失败,原因:" + ex.Message);
            }
            return obj;
        }

    }
}