ntwain/src/NTwain/TransferReadyEventArgs.cs

using NTwain.Data;
using System;

namespace NTwain
{
    /// <summary>
    /// Contains event data when a data transfer is ready to be processed.
    /// </summary>
    public class TransferReadyEventArgs : EventArgs
    {
        public TransferReadyEventArgs(TwainAppSession twain, TWSX imgXferMech, TWSX audXferMech, int pendingCount, TWEJ endOfJobFlag)
        {
            _twain = twain;
            ImgXferMech = imgXferMech;
            AudXferMech = audXferMech;
            PendingCount = pendingCount;
            EndOfJobFlag = endOfJobFlag;
        }

        /// <summary>
        /// Gets or sets whether to cancel the capture phase.
        /// </summary>
        public CancelType Cancel { get; set; }

        /// <summary>
        /// Gets the end of job flag value for this transfer if job control is enabled.
        /// </summary>
        public TWEJ EndOfJobFlag { get; }

        /// <summary>
        /// Gets the current transfer mech if working with images.
        /// </summary>
        public TWSX ImgXferMech { get; }

        /// <summary>
        /// Gets the current transfer mech if working with audio.
        /// </summary>
        public TWSX AudXferMech { get; }

        /// <summary>
        /// Gets the known pending transfer count. This may not be appilicable 
        /// for certain scanning modes.
        /// </summary>
        public int PendingCount { get; private set; }

        private readonly TwainAppSession _twain;

        /// <summary>
        /// If the transfer mech is file-related,
        /// setup the file transfer options here.
        /// </summary>
        /// <param name="fileXfer"></param>
        /// <returns></returns>
        public STS SetupFileTransfer(ref TW_SETUPFILEXFER fileXfer)
        {
            return _twain.SetFileXfer(ref fileXfer);
        }

        /// <summary>
        /// Gets the ext image info at this state for Kodak devices. Use any utility methods on it 
        /// to read the data. Remember to call <see cref="TW_EXTIMAGEINFO.Free(IMemoryManager)"/>
        /// when done.
        /// </summary>
        /// <param name="container">Container to query. Can be created with <see cref="TW_EXTIMAGEINFO.CreateRequest(TWEI[])"/></param>
        /// <returns></returns>
        public STS GetExtendedImageInfo(ref TW_EXTIMAGEINFO container)
        {
            if (_twain == null) return default;
            return _twain.GetExtendedImageInfoSpecial(ref container);
        }

        //TW_IMAGEINFO? _imgInfo;
        ///// <summary>
        ///// Gets the tentative image information for the current transfer if applicable.
        ///// This may differ from the final image depending on the transfer mode used (mostly when doing mem xfer).
        ///// </summary>
        //public TW_IMAGEINFO? PendingImageInfo
        //{
        //  get
        //  {
        //    // only get it if requested since it could be slow
        //    if (!_imgInfo.HasValue)
        //    {
        //      if (_twain.GetImageInfo(out TW_IMAGEINFO info).RC == TWRC.SUCCESS)
        //      {
        //        _imgInfo = info;
        //      }
        //    }
        //    return _imgInfo;
        //  }
        //}

    }

    public enum CancelType
    {
        /// <summary>
        /// No cancel.
        /// </summary>
        None,
        /// <summary>
        /// Skips current transfer.
        /// </summary>
        SkipCurrent,
        /// <summary>
        /// Stops feeder but continue receiving already scanned images in the app.
        /// </summary>
        Graceful,
        /// <summary>
        /// Stops feeder and discard any pending images.
        /// </summary>
        EndNow
    }
}