/*
 *                     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 Emgu.CV;
using Emgu.CV.CvEnum;
using System;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using UVtools.Core.Extensions;
using UVtools.Core.FileFormats;
using UVtools.Core.Layers;
using UVtools.Core.Objects;

namespace UVtools.Core.Operations;


public class OperationDoubleExposure : Operation
{
    #region Members
    private decimal _firstBottomExposure;
    private decimal _firstNormalExposure;
    private decimal _secondBottomExposure;
    private decimal _secondNormalExposure;
    private byte _firstBottomErodeIterations = 4;
    private byte _secondBottomErodeIterations;
    private byte _firstNormalErodeIterations = 1;
    private byte _secondNormalErodeIterations;
    private bool _secondLayerDifference = true;
    private byte _secondLayerDifferenceOverlapErodeIterations = 10;
    private bool _differentSettingsForSecondLayer;
    private bool _secondLayerLiftHeightEnabled = true;
    private decimal _secondLayerLiftHeight;
    private bool _secondLayerWaitTimeBeforeCureEnabled = true;
    private decimal _secondLayerWaitTimeBeforeCure;

    #endregion

    #region Overrides
    public override LayerRangeSelection StartLayerRangeSelection => LayerRangeSelection.Bottom;
    public override string IconClass => "fa-solid fa-grip-lines";
    public override string Title => "Double exposure";
    public override string Description =>
        "The double exposure method clones the selected layer range and print the same layer twice with different exposure times and strategies.\n" +
        "Can be used to eliminate the elephant foot effect or to harden a layer in two steps.\n" +
        "After this, do not apply any modification which reconstruct the z positions of the layers.\n" +
        "Note: To eliminate the elephant foot effect, the use of wall dimming method is recommended.";

    public override string ConfirmationText =>
        $"double exposure model layers {LayerIndexStart} through {LayerIndexEnd}";

    public override string ProgressTitle =>
        $"Double exposure from layers {LayerIndexStart} to {LayerIndexEnd}";

    public override string ProgressAction => "Cloned layers";

    public override string? ValidateSpawn()
    {
        if (!SlicerFile.CanUseLayerPositionZ || !SlicerFile.CanUseLayerLiftHeight || !SlicerFile.CanUseLayerExposureTime)
        {
            return NotSupportedMessage;
        }

        return null;
    }

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

        //if (LayerRangeHaveBottoms && _firstBottomExposure == _secondBottomExposure && _firstBottomErodeIterations == _secondBottomErodeIterations)
        //    sb.AppendLine("The settings for bottoms layers will produce exactly to equal layers");


        float lastPositionZ = SlicerFile[LayerIndexStart].PositionZ;
        for (uint layerIndex = LayerIndexStart + 1; layerIndex <= LayerIndexEnd; layerIndex++)
        {
            if (lastPositionZ == SlicerFile[layerIndex].PositionZ)
            {
                sb.AppendLine($"The selected layer range already have modified layers with same z position, starting at layer {layerIndex}. Not safe to continue.");
                break;
            }
            lastPositionZ = SlicerFile[layerIndex].PositionZ;
        }


        return sb.ToString();
    }

    public override string ToString()
    {
        var result = $"[1º exp: {_firstBottomExposure}/{_firstNormalExposure}s erode: {_firstBottomErodeIterations}/{_firstNormalErodeIterations}px] " +
                     $"[2º exp: {_secondBottomExposure}/{_secondNormalExposure}s erode: {_secondBottomErodeIterations}/{_secondNormalErodeIterations}px] " +
                     $"[Diff: {_secondLayerDifference} Overlap: {_secondLayerDifferenceOverlapErodeIterations}px]" + LayerRangeString;
        if (!string.IsNullOrEmpty(ProfileName)) result = $"{ProfileName}: {result}";
        return result;
    }
    #endregion

    #region Properties

    public decimal FirstBottomExposure
    {
        get => _firstBottomExposure;
        set => RaiseAndSetIfChanged(ref _firstBottomExposure, Math.Round(value, 2));
    }

    public decimal FirstNormalExposure
    {
        get => _firstNormalExposure;
        set => RaiseAndSetIfChanged(ref _firstNormalExposure, Math.Round(value, 2));
    }

    public decimal SecondBottomExposure
    {
        get => _secondBottomExposure;
        set => RaiseAndSetIfChanged(ref _secondBottomExposure, Math.Round(value, 2));
    }

    public decimal SecondNormalExposure
    {
        get => _secondNormalExposure;
        set => RaiseAndSetIfChanged(ref _secondNormalExposure, Math.Round(value, 2));
    }

    public byte FirstBottomErodeIterations
    {
        get => _firstBottomErodeIterations;
        set => RaiseAndSetIfChanged(ref _firstBottomErodeIterations, value);
    }

    public byte SecondBottomErodeIterations
    {
        get => _secondBottomErodeIterations;
        set => RaiseAndSetIfChanged(ref _secondBottomErodeIterations, value);
    }

    public byte FirstNormalErodeIterations
    {
        get => _firstNormalErodeIterations;
        set => RaiseAndSetIfChanged(ref _firstNormalErodeIterations, value);
    }

    public byte SecondNormalErodeIterations
    {
        get => _secondNormalErodeIterations;
        set => RaiseAndSetIfChanged(ref _secondNormalErodeIterations, value);
    }

    public bool SecondLayerDifference
    {
        get => _secondLayerDifference;
        set => RaiseAndSetIfChanged(ref _secondLayerDifference, value);
    }

    public byte SecondLayerDifferenceOverlapErodeIterations
    {
        get => _secondLayerDifferenceOverlapErodeIterations;
        set => RaiseAndSetIfChanged(ref _secondLayerDifferenceOverlapErodeIterations, value);
    }

    public bool DifferentSettingsForSecondLayer
    {
        get => _differentSettingsForSecondLayer;
        set => RaiseAndSetIfChanged(ref _differentSettingsForSecondLayer, value);
    }

    public bool SecondLayerLiftHeightEnabled
    {
        get => _secondLayerLiftHeightEnabled;
        set => RaiseAndSetIfChanged(ref _secondLayerLiftHeightEnabled, value);
    }

    public decimal SecondLayerLiftHeight
    {
        get => _secondLayerLiftHeight;
        set => RaiseAndSetIfChanged(ref _secondLayerLiftHeight, value);
    }

    public bool SecondLayerWaitTimeBeforeCureEnabled
    {
        get => _secondLayerWaitTimeBeforeCureEnabled;
        set => RaiseAndSetIfChanged(ref _secondLayerWaitTimeBeforeCureEnabled, value);
    }

    public decimal SecondLayerWaitTimeBeforeCure
    {
        get => _secondLayerWaitTimeBeforeCure;
        set => RaiseAndSetIfChanged(ref _secondLayerWaitTimeBeforeCure, value);
    }


    public KernelConfiguration Kernel { get; set; } = new();

    #endregion

    #region Constructor

    public OperationDoubleExposure() { }

    public OperationDoubleExposure(FileFormat slicerFile) : base(slicerFile)
    {
        if (SlicerFile.SupportPerLayerSettings)
        {
            _differentSettingsForSecondLayer = true;
            if (SlicerFile.SupportsGCode)
            {
                _secondLayerLiftHeight = 0;
                _secondLayerWaitTimeBeforeCure = 2;
            }
            else
            {
                _secondLayerLiftHeight = 0.1m;
                _secondLayerWaitTimeBeforeCure = 0;
            }
        }
    }

    public override void InitWithSlicerFile()
    {
        base.InitWithSlicerFile();
        if (_firstBottomExposure <= 0) _firstBottomExposure = (decimal)SlicerFile.BottomExposureTime;
        if (_firstNormalExposure <= 0) _firstNormalExposure = (decimal)SlicerFile.ExposureTime;
        if (_secondBottomExposure <= 0) _secondBottomExposure = (decimal)SlicerFile.ExposureTime;
        if (_secondNormalExposure <= 0) _secondNormalExposure = (decimal)SlicerFile.ExposureTime;
    }

    #endregion

    #region Equality

    protected bool Equals(OperationDoubleExposure other)
    {
        return _firstBottomExposure == other._firstBottomExposure && _firstNormalExposure == other._firstNormalExposure && _secondBottomExposure == other._secondBottomExposure && _secondNormalExposure == other._secondNormalExposure && _firstBottomErodeIterations == other._firstBottomErodeIterations && _secondBottomErodeIterations == other._secondBottomErodeIterations && _firstNormalErodeIterations == other._firstNormalErodeIterations && _secondNormalErodeIterations == other._secondNormalErodeIterations && _secondLayerDifference == other._secondLayerDifference && _secondLayerDifferenceOverlapErodeIterations == other._secondLayerDifferenceOverlapErodeIterations && _differentSettingsForSecondLayer == other._differentSettingsForSecondLayer && _secondLayerLiftHeightEnabled == other._secondLayerLiftHeightEnabled && _secondLayerLiftHeight == other._secondLayerLiftHeight && _secondLayerWaitTimeBeforeCureEnabled == other._secondLayerWaitTimeBeforeCureEnabled && _secondLayerWaitTimeBeforeCure == other._secondLayerWaitTimeBeforeCure;
    }

    public override bool Equals(object? obj)
    {
        if (ReferenceEquals(null, obj)) return false;
        if (ReferenceEquals(this, obj)) return true;
        if (obj.GetType() != this.GetType()) return false;
        return Equals((OperationDoubleExposure)obj);
    }

    public override int GetHashCode()
    {
        var hashCode = new HashCode();
        hashCode.Add(_firstBottomExposure);
        hashCode.Add(_firstNormalExposure);
        hashCode.Add(_secondBottomExposure);
        hashCode.Add(_secondNormalExposure);
        hashCode.Add(_firstBottomErodeIterations);
        hashCode.Add(_secondBottomErodeIterations);
        hashCode.Add(_firstNormalErodeIterations);
        hashCode.Add(_secondNormalErodeIterations);
        hashCode.Add(_secondLayerDifference);
        hashCode.Add(_secondLayerDifferenceOverlapErodeIterations);
        hashCode.Add(_differentSettingsForSecondLayer);
        hashCode.Add(_secondLayerLiftHeightEnabled);
        hashCode.Add(_secondLayerLiftHeight);
        hashCode.Add(_secondLayerWaitTimeBeforeCureEnabled);
        hashCode.Add(_secondLayerWaitTimeBeforeCure);
        return hashCode.ToHashCode();
    }

    #endregion

    #region Methods

    protected override bool ExecuteInternally(OperationProgress progress)
    {
        var layers = new Layer[SlicerFile.LayerCount+LayerRangeCount];

        // Untouched
        for (uint i = 0; i < LayerIndexStart; i++)
        {
            layers[i] = SlicerFile[i];
        }

        int bottomLayers = SlicerFile.BottomLayerCount;

        Parallel.For(LayerIndexStart, LayerIndexEnd + 1, CoreSettings.GetParallelOptions(progress), layerIndex =>
        {
            progress.PauseIfRequested();
            var firstLayer = SlicerFile[layerIndex];
            var secondLayer = firstLayer.Clone();
            var isBottomLayer = firstLayer.IsBottomLayer;

            if (isBottomLayer)
            {
                Interlocked.Increment(ref bottomLayers);
            }

            firstLayer.ExposureTime = (float)( isBottomLayer ? _firstBottomExposure : _firstNormalExposure);
            secondLayer.ExposureTime = (float)(isBottomLayer ? _secondBottomExposure : _secondNormalExposure);

            if (_differentSettingsForSecondLayer)
            {
                if (_secondLayerLiftHeightEnabled) secondLayer.LiftHeightTotal = (float)_secondLayerLiftHeight;
                if (_secondLayerWaitTimeBeforeCureEnabled) secondLayer.SetWaitTimeBeforeCureOrLightOffDelay((float)_secondLayerWaitTimeBeforeCure);
            }

            byte firstErodeIterations = isBottomLayer ? _firstBottomErodeIterations : _firstNormalErodeIterations;
            byte secondErodeIterations = isBottomLayer ? _secondBottomErodeIterations : _secondNormalErodeIterations;

            using (var mat = firstLayer.LayerMat)
            {
                //using Mat matOriginal = _secondExposureLayerDifference ? mat.Clone() : null;
                if (firstErodeIterations > 0 && firstErodeIterations == secondErodeIterations)
                {
                    int tempIterations = firstErodeIterations;
                    var kernel = Kernel.GetKernel(ref tempIterations);
                    CvInvoke.Erode(mat, mat, kernel, EmguExtensions.AnchorCenter, tempIterations, BorderType.Reflect101, default);
                    firstLayer.LayerMat = mat;
                    firstLayer.CopyImageTo(secondLayer);

                    if (_secondLayerDifference && _secondLayerDifferenceOverlapErodeIterations > 0)
                    {
                        tempIterations = _secondLayerDifferenceOverlapErodeIterations;
                        kernel = Kernel.GetKernel(ref tempIterations);
                        using var matErode = new Mat();
                        CvInvoke.Erode(mat, matErode, kernel, EmguExtensions.AnchorCenter, tempIterations, BorderType.Reflect101, default);
                        //CvInvoke.Threshold(matErode, matErode, 127, 255, ThresholdType.Binary);
                        CvInvoke.Subtract(mat, matErode, mat);
                        secondLayer.LayerMat = mat;
                    }
                    else
                    {
                        firstLayer.CopyImageTo(secondLayer);
                    }
                }
                else
                {
                    Mat? firstMat = null;
                    Mat? secondMat = null;
                    if (firstErodeIterations > 0)
                    {
                        int tempIterations = firstErodeIterations;
                        var kernel = Kernel.GetKernel(ref tempIterations);
                        firstMat = new Mat();
                        CvInvoke.Erode(mat, firstMat, kernel, EmguExtensions.AnchorCenter, tempIterations, BorderType.Reflect101, default);
                        firstLayer.LayerMat = firstMat;
                    }

                    if (secondErodeIterations > 0)
                    {
                        int tempIterations = secondErodeIterations;
                        var kernel = Kernel.GetKernel(ref tempIterations);
                        secondMat = new Mat();
                        CvInvoke.Erode(mat, secondMat, kernel, EmguExtensions.AnchorCenter, tempIterations, BorderType.Reflect101, default);
                    }

                    if(firstMat is not null && _secondLayerDifference)
                    {
                        if (firstErodeIterations + _secondLayerDifferenceOverlapErodeIterations != secondErodeIterations)
                        {
                            if (_secondLayerDifferenceOverlapErodeIterations > 0 &&
                                firstErodeIterations + _secondLayerDifferenceOverlapErodeIterations != secondErodeIterations)
                            {
                                int tempIterations = _secondLayerDifferenceOverlapErodeIterations;
                                var kernel = Kernel.GetKernel(ref tempIterations);
                                CvInvoke.Erode(firstMat, firstMat, kernel, EmguExtensions.AnchorCenter, tempIterations, BorderType.Reflect101, default);
                                //CvInvoke.Threshold(firstMat, firstMat, 127, 255, ThresholdType.Binary);
                            }

                            CvInvoke.AbsDiff(firstMat, secondMat ?? mat, mat);
                            secondLayer.LayerMat = mat;
                        }
                    }
                    else if (secondMat is not null)
                    {
                        secondLayer.LayerMat = secondMat;
                    }

                    firstMat?.Dispose();
                    secondMat?.Dispose();
                }
            }

            uint index = LayerIndexStart + (uint)(layerIndex - LayerIndexStart) * 2; 
                
            layers[index] = firstLayer;
            layers[index + 1] = secondLayer;

            progress.LockAndIncrement();
        });

        // Untouched
        for (uint i = LayerIndexEnd+1; i < SlicerFile.LayerCount; i++)
        {
            layers[i + LayerRangeCount] = SlicerFile[i];
        }

        SlicerFile.SuppressRebuildPropertiesWork(() =>
        {
            SlicerFile.BottomLayerCount = (ushort)bottomLayers;
            SlicerFile.Layers = layers;
        });

        return !progress.Token.IsCancellationRequested;
    }

    #endregion
}