using System;
using System.Collections.Generic;
using System.Text;
using System.Web.UI.WebControls;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
using Microsoft.SharePoint.Utilities;

namespace BlackBlade.ListActions.DownloadAsZip
{
    public class DownloadZipFileStatus : System.Web.UI.Page
    {
        protected Literal ltrClientRedirect;

        protected override void OnInit(EventArgs e)
        {
            base.OnInit(e);

            this.Load += new EventHandler(DownloadZipFileStatus_Load);
        }

        void DownloadZipFileStatus_Load(object sender, EventArgs e)
        {
            //this page expects the following HTTP request parameters
            // SID: Guid of the SharePoint Web Front End server where the zip file is located
            // ZipPath: Path on the SID where the zip file is located. This path
            //          should be relative to the "\\SID\admin$\temp\zip\" folder.
            // LastSize: The previous size of the zip file in bytes. If the current size
            //          is the same as the last size, then the file zip process
            //          is complete

            //get the parameters from the request
            Guid serverID;
            try
            {
                serverID = new Guid(this.Request["SID"]);
            }
            catch (Exception ex)
            {
                throw new ArgumentNullException("SID", ex);
            }

            string zipFilePath = this.Request["ZipPath"];
            if (string.IsNullOrEmpty(zipFilePath))
                throw new ArgumentNullException("ZipPath");

            //get the server name from the sharepoint farm
            SPFarm farm = SPFarm.Local;
            string serverName = null;
            try
            {
                serverName = farm.Servers[serverID].Name;
            }
            catch (Exception ex)
            {
                throw new ArgumentException("The " + serverID.ToString() + " is not a valid server id in this farm.", "SID", ex);
            }

            long lngLastSize = 0;
            try
            {
                lngLastSize = long.Parse(this.Request["LastSize"]);
            }
            catch (Exception)
            {
            }

            //generate the complete path for the zip file
            string fullZipFilePath = @"\\" + serverName + @"\admin$\temp\zip\" + zipFilePath;

            //ensure that the temporary directory exists
            System.IO.FileInfo fi = new System.IO.FileInfo(fullZipFilePath);
            if (!fi.Directory.Exists)
                throw new System.IO.FileNotFoundException("Could not access the temporary location of the compressed file.", fullZipFilePath);


            //check to see if the zip file size has changed since last time
            long lngSize = fi.Length;
            if (lngLastSize == lngSize)
                //the processing is finished. redirect to the results page
                this.Response.Redirect(string.Format("DownloadZipFileResult.aspx?SID={0}&ZipPath={1}",
                                        SPHttpUtility.UrlKeyValueEncode(serverID),
                                        SPHttpUtility.UrlKeyValueEncode(zipFilePath)));
            else
            {
                //the processing is still going. check back in 3 seconds
                string strClientRedirect =
                    "<script type=\"text/javascript\"> \r\n" +
                    "   window.setTimeout(\"window.location = '{0}'\", 3000); \r\n" +
                    "</script>";

                string strRedirectUrl = string.Format("DownloadZipFileStatus.aspx?SID={0}&ZipPath={1}&LastSize={2}",
                                    SPHttpUtility.UrlKeyValueEncode(serverID.ToString()),
                                    SPHttpUtility.UrlKeyValueEncode(zipFilePath),
                                    SPHttpUtility.UrlKeyValueEncode(lngSize.ToString()));

                this.ltrClientRedirect.Text = string.Format(strClientRedirect, strRedirectUrl);
            }

        }   
    }
}