using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
using System.IO;
using System.Web;
using System.Configuration;

namespace BLL
{
    public static class FileStructService
    {
        /// <summary>
        /// 获取附件数据流类
        /// </summary>
        /// <param name="attachUrl">附件路径</param>
        /// <returns></returns>
        public static List<byte[]> GetFileStructByAttachUrl(string attachUrl)
        {
            List<byte[]> fileContext = new List<byte[]>();
            if (!String.IsNullOrEmpty(attachUrl))
            {
                string filePath = string.Empty;
                string physicalpath = Funs.RootPath;
                    //HttpContext.Current.Request.PhysicalApplicationPath;                
                filePath = physicalpath + attachUrl;               
                if (File.Exists(filePath))
                {
                    FileInfo fileInfo = new FileInfo(filePath);
                    Stream stream = fileInfo.OpenRead();
                    //读取指定大小的文件流内容到uploadFile.Context以便上传
                    int b;
                    while (stream.Position > -1 && stream.Position < stream.Length)
                    {
                        if (stream.Length - stream.Position >= 20000000)
                        {
                            b = 20000000;
                        }
                        else
                        {
                            b = (int)(stream.Length - stream.Position);
                        }

                        byte[] filebyte = new byte[b];
                        stream.Read(filebyte, 0, b);
                        fileContext.Add(filebyte);
                    }
                    stream.Close();
                }
            }

            return fileContext;
        }

        /// <summary>
        /// 获取附件数据流类 多附件的情况
        /// </summary>
        /// <param name="attachUrl">附件路径</param>
        /// <returns></returns>
        public static List<byte[]> GetMoreFileStructByAttachUrl(string attachUrl)
        {
            List<byte[]> fileContext = new List<byte[]>();
            if (!String.IsNullOrEmpty(attachUrl))
            {
                string[] strs = attachUrl.Trim().Split(',');
                foreach (var item in strs)
                {
                    string filePath = string.Empty;
                    string physicalpath = ConfigurationManager.AppSettings["localRoot"];
                    //HttpContext.Current.Request.PhysicalApplicationPath;    
                    filePath = physicalpath + item;
                    if (File.Exists(filePath))
                    {
                        fileContext.Add(fileConvertByte(item));
                    }
                }
            }
            return fileContext;
        }


        #region 二进制数据转换为附件
        /// <summary>
        /// 二进制数据转换为附件
        /// </summary>
        /// <param name="data">二进制数据</param>
        /// <param name="fileName">附件.后缀</param>
        /// <param name="savePath">保存路径</param>
        /// <returns>保存的相对路径</returns>
        public static string ByteConvertFile(byte[] data, string fileName, string savePath)
        {
            string physicalpath = (ConfigurationManager.AppSettings["localRoot"] + "\\" + savePath).Replace("\\\\", "\\");
            if (!System.IO.Directory.Exists(savePath))
            {
                Directory.CreateDirectory(savePath);
            }

            savePath += fileName;
            FileStream fs;
            if (System.IO.File.Exists(savePath))
            {
                fs = new FileStream(savePath, FileMode.Truncate);
            }
            else
            {
                fs = new FileStream(savePath, FileMode.CreateNew);
            }
            BinaryWriter br = new BinaryWriter(fs);
            br.Write(data, 0, data.Length);
            br.Close();
            fs.Close();

            return savePath;
        }
        #endregion

        #region 附件转换二进制数据(用于保存数据库)
        /// <summary>
        /// 附件转换二进制数据(用于保存数据库)
        /// </summary>
        /// <param name="filePath">附件路径</param>
        /// <returns>二进制</returns>
        public static byte[] fileConvertByte(string filePath)
        {
            string physicalpath = (ConfigurationManager.AppSettings["localRoot"] + "\\" + filePath).Replace("\\\\", "\\");
            byte[] bytContent = null;
            System.IO.FileStream fs = null;
            System.IO.BinaryReader br = null;
            try
            {
                fs = new FileStream(physicalpath, System.IO.FileMode.Open);
            }
            catch
            {
            }
            br = new BinaryReader((Stream)fs);
            bytContent = br.ReadBytes((Int32)fs.Length);
            fs.Dispose();
            return bytContent;
        }
        #endregion
    }
}