using System;
using System.IO;
using System.Linq;
using System.Web.Mvc;
using ICSharpCode.SharpZipLib.Zip;
using Kreta.BusinessLogic.Helpers;
using Kreta.Resources;
using Kreta.Web.Helpers;
using Kreta.Web.Security;

namespace Kreta.Web.Areas.Adatszolgaltatasok.Logic
{
    public static class ItmAdatszolgaltatasLogic
    {
        public static FileStreamResult EllenorzoTablazatLetoltese()
        {
            var memoryStreamList = new ItmAdatszolgaltatasHelper(ConnectionTypeExtensions.GetSessionConnectionType()).IntezmenyAdatok();

            var fajlNev = $"{ ClaimData.IntezmenyAzonosito }_{ AdatszolgaltatasokResource.ItmAdatszolgaltatasExcelExportFajlNev}_{ DateTime.Now.ToString("yyyyMMddHHmm")}";

            if (memoryStreamList.Count == 1)
            {
                return new FileStreamResult(memoryStreamList.FirstOrDefault(), Constants.ImportExport.FileFormatXlsx)
                {
                    FileDownloadName = $"{fajlNev}.{Constants.ImportExport.FileFormatXlsx}"
                };
            }
            else
            {
                var outputStream = new MemoryStream();
                var zipOutputStream = new ZipOutputStream(outputStream);

                var buffer = new byte[4096];

                for (int i = 0; i < memoryStreamList.Count; i++)
                {
                    var entry = new ZipEntry($"{fajlNev}_{i}.{Constants.ImportExport.FileFormatXlsx}");
                    zipOutputStream.PutNextEntry(entry);

                    int sourceBytes;
                    do
                    {
                        sourceBytes = memoryStreamList[i].Read(buffer, 0, buffer.Length);
                        zipOutputStream.Write(buffer, 0, sourceBytes);
                    } while (sourceBytes > 0);
                }
                zipOutputStream.Finish();
                outputStream.Position = 0;

                return new FileStreamResult(outputStream, Constants.ImportExport.ContentType)
                {
                    FileDownloadName = $"{fajlNev}.{Constants.ImportExport.FileFormatZip}"
                };
            }
        }
    }
}