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

namespace Bowin.Common.Mvc
{
    public class StaticFileWriteFilterAttribute : ActionFilterAttribute
    {
        public override void OnResultExecuted(ResultExecutedContext filterContext)
        {
            //filterContext.HttpContext.Response.Write("OnResultExecuted</br>");  

            if (filterContext.HttpContext.Response.StatusCode == 200)
            {
                filterContext.HttpContext.Response.Filter = new StaticFileWriteResponseFilterWrapper(filterContext.HttpContext.Response.Filter, filterContext);
            }
            // filterContext.HttpContext.Response.Charset = "utf8";  
            base.OnResultExecuted(filterContext);
        }

        class StaticFileWriteResponseFilterWrapper : System.IO.Stream
        {
            private Stream inner;
            private FileStream writer;
            private ControllerContext context;
            private int expireSconds;
            private bool filter;
            private string tempPath, path;

            public StaticFileWriteResponseFilterWrapper(System.IO.Stream s, ControllerContext context, int expireSeconds = 600)
            {
                this.filter = false;
                this.inner = s;
                this.context = context;
                this.expireSconds = expireSeconds;
                this.EnsureStaticFile();
            }

            void EnsureStaticFile()
            {
                this.path = this.context.HttpContext.Server.MapPath(HttpContext.Current.Request.Path);

                if (!Path.HasExtension(path))
                {
                    return;
                }
                if (!".html".Equals(Path.GetExtension(HttpContext.Current.Request.Path)))
                {
                    return;
                }

                if (File.Exists(path))
                {
                    var delay = DateTime.UtcNow - File.GetCreationTimeUtc(path);
                    if (delay.TotalSeconds <= this.expireSconds)
                    {
                        return;
                    }

                    File.Delete(path);
                }
                else
                {
                    var dir = Path.GetDirectoryName(path);
                    if (!Directory.Exists(dir))
                    {
                        try
                        {
                            Directory.CreateDirectory(Path.GetDirectoryName(path));
                        }
                        catch
                        { }
                    }
                }

                this.filter = true;
                this.tempPath = this.path + "_" + DateTime.Now.Ticks;

                try
                {
                    writer = new FileStream(tempPath, FileMode.Create, FileAccess.Write);
                }
                catch
                {
                    this.filter = false;
                }
            }



            public override bool CanRead
            {
                get { return inner.CanRead; }
            }

            public override bool CanSeek
            {
                get { return inner.CanSeek; }
            }

            public override bool CanWrite
            {
                get { return inner.CanWrite; }
            }

            public override void Flush()
            {
                inner.Flush();
            }



            public override long Length
            {
                get { return inner.Length; }
            }

            public override long Position
            {
                get
                {
                    return inner.Position;
                }
                set
                {
                    inner.Position = value;
                }
            }

            public override int Read(byte[] buffer, int offset, int count)
            {
                return inner.Read(buffer, offset, count);
            }

            public override long Seek(long offset, System.IO.SeekOrigin origin)
            {
                return inner.Seek(offset, origin);
            }

            public override void SetLength(long value)
            {
                inner.SetLength(value);
            }

            public override void Write(byte[] buffer, int offset, int count)
            {
                try
                {
                    inner.Write(buffer, offset, count);
                }
                catch (Exception ex)
                {
                }

                try
                {
                    this.writer.Write(buffer, offset, count);
                }
                catch (Exception ex)
                {

                }
            }

            protected override void Dispose(bool disposing)
            {
                if (this.filter)
                {
                    try
                    {
                        if (this.writer != null)
                        {
                            this.writer.Dispose();
                            this.writer = null;
                        }

                        File.Delete(this.path);
                        File.Move(this.tempPath, this.path);
                        #region 生成文件日志

                        #endregion
                    }
                    catch
                    { }

                }
                base.Dispose(disposing);
            }
        }
    }
}