using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Web;
using System.Web.Script.Serialization;

namespace CY.WebForm.Pages.business
{
    /// <summary>
    /// FileUploadHandler 的摘要说明
    /// </summary>
    public class FileUploadHandler : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "application/json";

            try
            {
                if (context.Request.Files.Count > 0)
                {
                    HttpPostedFile file = context.Request.Files["file"];

                    // 验证文件
                    if (file.ContentLength > 0)
                    {
                        // 检查文件大小是否超过5MB
                        if (file.ContentLength > 5 * 1024 * 1024) // 5MB
                        {
                            throw new Exception("文件不能大于5M");
                        }
                        // 设置保存路径
                        string fileName = DateTime.Now.ToString("HHmmssfff")+ Path.GetFileName(file.FileName);
                        string riqi = DateTime.Now.ToString("yyyyMMdd");
                        string fileDirectory = "/UpFile/UpFile/" + riqi + "/";
                        if ((fileDirectory + fileName).Length>400) // 5MB
                        {
                            throw new Exception("文件名字过长");
                        }
                        string fileExtension = Path.GetExtension(fileName);
                        string savePath = context.Server.MapPath("~"+ fileDirectory) + fileName;

                        // 确保目录存在
                        if (!Directory.Exists(context.Server.MapPath("~"+ fileDirectory)))
                        {
                            Directory.CreateDirectory(context.Server.MapPath("~"+ fileDirectory));
                        }

                        // 保存文件
                        file.SaveAs(savePath);

                        // 返回JSON响应
                        var response = new
                        {
                            code = 1,
                            message = "文件上传成功",
                            fileName = fileName,
                            fileSize = file.ContentLength,
                            data = fileDirectory + fileName
                        };

                        context.Response.Write(new JavaScriptSerializer().Serialize(response));
                    }
                    else
                    {
                        throw new Exception("文件内容为空");
                    }
                }
                else
                {
                    throw new Exception("没有接收到文件");
                }
            }
            catch (Exception ex)
            {
                var errorResponse = new
                {
                    code = 2,
                    message = ex.Message
                };

                context.Response.Write(new JavaScriptSerializer().Serialize(errorResponse));
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}