/*
 *                     GNU AFFERO GENERAL PUBLIC LICENSE
 *                       Version 3, 19 November 2007
 *  Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 *  Everyone is permitted to copy and distribute verbatim copies
 *  of this license document, but changing it is not allowed.
 */

using System;
using System.Text;
using System.Threading.Tasks;
using Emgu.CV;
using Emgu.CV.CvEnum;
using UVtools.Core.Extensions;
using UVtools.Core.FileFormats;

namespace UVtools.Core.Operations
{
    [Serializable]
    public sealed class OperationLayerExportHeatMap : Operation
    {
        #region Members
        private string _filePath;
        private bool _cropByRoi = true;

        #endregion

        #region Overrides

        public override bool CanHaveProfiles => false;
        public override string Title => "Export layers to heat map";

        public override string Description =>
            "Export a layer range to a grayscale heat map image that represents the median of the mass in the Z depth/perception.\n" +
            "The pixel brightness/intensity shows where the most mass are concentrated.";

        public override string ConfirmationText =>
            $"generate a heatmap from layers {LayerIndexStart} through {LayerIndexEnd}?";

        public override string ProgressTitle =>
            $"Generating a heatmap from layers {LayerIndexStart} through {LayerIndexEnd}";

        public override string ProgressAction => "Packed layers";

        public override string ValidateInternally()
        {
            var sb = new StringBuilder();

            if (LayerRangeCount < 2)
            {
                sb.AppendLine("To generate a heat map at least two layers are required.");
            }

            return sb.ToString();
        }

        public override string ToString()
        {
            var result = $"[Crop by ROI: {_cropByRoi}]" +
                         LayerRangeString;
            if (!string.IsNullOrEmpty(ProfileName)) result = $"{ProfileName}: {result}";
            return result;
        }

        #endregion

        #region Properties

        public string FilePath
        {
            get => _filePath;
            set => RaiseAndSetIfChanged(ref _filePath, value);
        }

        public bool CropByROI
        {
            get => _cropByRoi;
            set => RaiseAndSetIfChanged(ref _cropByRoi, value);
        }

        #endregion

        #region Constructor

        public OperationLayerExportHeatMap()
        { }

        public OperationLayerExportHeatMap(FileFormat slicerFile) : base(slicerFile)
        {
            _filePath = SlicerFile.FileFullPath + ".heatmap.png";
        }

        #endregion

        #region Methods

        protected override bool ExecuteInternally(OperationProgress progress)
        {
            using var sumMat32 = EmguExtensions.InitMat(SlicerFile.Resolution, 1, DepthType.Cv32S);
            var sumMat32Roi = GetRoiOrDefault(sumMat32);
            using var mask = GetMask(sumMat32);
            

            Parallel.For(LayerIndexStart, LayerIndexEnd+1, layerIndex =>
            {
                if (progress.Token.IsCancellationRequested) return;

                using var mat = SlicerFile[layerIndex].LayerMat;
                using var mat32 = new Mat();
                mat.ConvertTo(mat32, DepthType.Cv32S);
                var mat32Roi = GetRoiOrDefault(mat32);

                lock (progress.Mutex)
                {
                    CvInvoke.Add(sumMat32Roi, mat32Roi, sumMat32Roi, mask);
                    progress++;
                }
            });

            if (!progress.Token.IsCancellationRequested)
            {
                using var sumMat = EmguExtensions.InitMat(sumMat32.Size);
                sumMat32.ConvertTo(sumMat, DepthType.Cv8U, 1.0 / LayerRangeCount);
                if (_cropByRoi && HaveROI)
                {
                    var sumMatRoi = GetRoiOrDefault(sumMat);
                    sumMatRoi.Save(_filePath);
                }
                else
                {
                    sumMat.Save(_filePath);
                }
            }

            return !progress.Token.IsCancellationRequested;
        }

        #endregion

        #region Equality

        private bool Equals(OperationLayerExportHeatMap other)
        {
            return _filePath == other._filePath && _cropByRoi == other._cropByRoi;
        }

        public override bool Equals(object obj)
        {
            return ReferenceEquals(this, obj) || obj is OperationLayerExportHeatMap other && Equals(other);
        }

        public override int GetHashCode()
        {
            return HashCode.Combine(_filePath, _cropByRoi);
        }

        #endregion
    }
}