using System.Collections.ObjectModel;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Text.Json;
using View_by_Distance.Face.Models;
using View_by_Distance.Metadata.Models;
using View_by_Distance.Property.Models;
using View_by_Distance.Property.Models.Stateless;
using View_by_Distance.Resize.Models;
using View_by_Distance.Shared.Models;
using View_by_Distance.Shared.Models.Properties;
using View_by_Distance.Shared.Models.Stateless;

namespace View_by_Distance.FaceParts.Models;

/// <summary>
// *.png
/// </summary>
public class D2_FaceParts
{

    protected readonly string _FileNameExtension;
    public string FileNameExtension => _FileNameExtension;

    private readonly ImageCodecInfo _ImageCodecInfo;
    private readonly bool _CheckDFaceAndUpWriteDates;
    private readonly bool _OverrideForFaceLandmarkImages;
    private readonly EncoderParameters _EncoderParameters;
    private readonly List<string> _AngleBracketCollection;
    private readonly Dictionary<string, string[]> _FileGroups;
    private readonly IPropertyConfiguration _PropertyConfiguration;

    public D2_FaceParts(IPropertyConfiguration propertyConfiguration, ImageCodecInfo imageCodecInfo, EncoderParameters encoderParameters, string filenameExtension, bool checkDFaceAndUpWriteDates, bool overrideForFaceLandmarkImages)
    {
        _FileGroups = [];
        _ImageCodecInfo = imageCodecInfo;
        _EncoderParameters = encoderParameters;
        _FileNameExtension = filenameExtension;
        _AngleBracketCollection = [];
        _PropertyConfiguration = propertyConfiguration;
        _CheckDFaceAndUpWriteDates = checkDFaceAndUpWriteDates;
        _OverrideForFaceLandmarkImages = overrideForFaceLandmarkImages;
    }

    public override string ToString()
    {
        string result = JsonSerializer.Serialize(this, new JsonSerializerOptions() { WriteIndented = true });
        return result;
    }

    public void Update(string dResultsFullGroupDirectory)
    {
        _FileGroups.Clear();
        ReadOnlyDictionary<string, string[]> keyValuePairs = Shared.Models.Stateless.Methods.IPath.GetKeyValuePairs(_PropertyConfiguration, dResultsFullGroupDirectory, [_PropertyConfiguration.ResultContent]);
        foreach (KeyValuePair<string, string[]> keyValuePair in keyValuePairs)
            _FileGroups.Add(keyValuePair.Key, keyValuePair.Value);
    }

    public void SetAngleBracketCollection(IPropertyConfiguration propertyConfiguration, string d2ResultsFullGroupDirectory, string sourceDirectory)
    {
        _AngleBracketCollection.Clear();
        _AngleBracketCollection.AddRange(IResult.GetDirectoryInfoCollection(propertyConfiguration,
                                                                            sourceDirectory,
                                                                            d2ResultsFullGroupDirectory,
                                                                            contentDescription: "n gif file(s) for each face found",
                                                                            singletonDescription: string.Empty,
                                                                            collectionDescription: string.Empty,
                                                                            converted: true));
    }

    public string GetFacePartsDirectory(IPropertyConfiguration propertyConfiguration, string dResultsFullGroupDirectory, Item item, bool includeNameWithoutExtension)
    {
        string result;
        bool angleBracketCollectionAny = _AngleBracketCollection.Count != 0;
        if (!angleBracketCollectionAny)
        {
            if (item.FilePath.DirectoryName is null)
                throw new NullReferenceException(nameof(item.FilePath.DirectoryName));
            SetAngleBracketCollection(propertyConfiguration, dResultsFullGroupDirectory, item.FilePath.DirectoryName);
        }
        if (includeNameWithoutExtension)
            result = Path.Combine(_AngleBracketCollection[0].Replace("<>", _PropertyConfiguration.ResultContent), item.FilePath.NameWithoutExtension);
        else
        {
            result = _AngleBracketCollection[0].Replace("<>", $"[{_PropertyConfiguration.ResultContent}]");
            if (!Directory.Exists(result))
                _ = Directory.CreateDirectory(result);
        }
        if (!angleBracketCollectionAny)
            _AngleBracketCollection.Clear();
        return result;
    }

    private static void GetPointBounds(PointF[] points, out float xMinimum, out float xMaximum, out float yMinimum, out float yMaximum)
    {
        xMinimum = points[0].X;
        xMaximum = xMinimum;
        yMinimum = points[0].Y;
        yMaximum = yMinimum;
        foreach (PointF point in points)
        {
            if (xMinimum > point.X)
                xMinimum = point.X;
            if (xMaximum < point.X)
                xMaximum = point.X;
            if (yMinimum > point.Y)
                yMinimum = point.Y;
            if (yMaximum < point.Y)
                yMaximum = point.Y;
        }
    }

#pragma warning disable CA1416

    private static Bitmap RotateBitmap(Bitmap bitmap, float angle)
    {
        Bitmap result;
#if Linux
        throw new Exception("Built on Linux!"); 
#elif OSX
        throw new Exception("Built on macOS!"); 
#elif Windows
        // Make save Matrix to represent rotation
        // by this angle.
        Matrix rotate_at_origin = new();
        rotate_at_origin.Rotate(angle);

        // Rotate the image's corners to see how big
        // it will be after rotation.
        PointF[] points =
        [
                new(0, 0),
            new(bitmap.Width, 0),
            new(bitmap.Width, bitmap.Height),
            new(0, bitmap.Height),
        ];
        rotate_at_origin.TransformPoints(points);
        float xMinimum, xMaximum, yMinimum, yMaximum;
        GetPointBounds(points, out xMinimum, out xMaximum, out yMinimum, out yMaximum);

        // Make save bitmap to hold the rotated result.
        int wid = (int)Math.Round(xMaximum - xMinimum);
        int hgt = (int)Math.Round(yMaximum - yMinimum);
        result = new Bitmap(wid, hgt);

        // Create the real rotation transformation.
        Matrix rotate_at_center = new();
        rotate_at_center.RotateAt(angle,
            new PointF(wid / 2f, hgt / 2f));

        // Draw the image onto the new bitmap rotated.
        using (Graphics gr = Graphics.FromImage(result))
        {
            // Use smooth image interpolation.
            gr.InterpolationMode = InterpolationMode.High;

            // Clear with the color in the image's upper left corner.
            gr.Clear(bitmap.GetPixel(0, 0));

            // For debugging. (It's easier to see the background.)
            // gr.Clear(Color.LightBlue);

            // Set up the transformation to rotate.
            gr.Transform = rotate_at_center;

            // Draw the image centered on the bitmap.
            int x = (wid - bitmap.Width) / 2;
            int y = (hgt - bitmap.Height) / 2;
            gr.DrawImage(bitmap, x, y);
        }
#endif
        // Return the result bitmap.
        return result;
    }

    private static Bitmap RotateBitmap(Image image, float angle)
    {
        Bitmap result;
        Bitmap bitmap = new(image);
        result = RotateBitmap(bitmap, angle);
        bitmap?.Dispose();
        return result;
    }

    private void SaveFaceParts(int pointSize, FileHolder resizedFileHolder, bool saveRotated, List<(Shared.Models.Face, string, string)> collection)
    {
        int x;
        int y;
        double? α;
        int width;
        int height;
        Bitmap rotated;
        foreach ((Shared.Models.Face face, string fileName, string rotatedFileName) in collection)
        {
            if (face.FaceEncoding is null)
                continue;
            try
            {
                using (Image image = Image.FromFile(resizedFileHolder.FullName))
                {
                    using Graphics graphic = Graphics.FromImage(image);
                    if (face.FaceParts is null || face.FaceParts.Count == 0)
                    {
                        if (face.Location is null)
                            continue;
                        width = face.Location.Right - face.Location.Left;
                        height = face.Location.Bottom - face.Location.Top;
                        graphic.DrawEllipse(Pens.Red, face.Location.Left, face.Location.Top, width, height);
                    }
                    else
                    {
                        foreach ((FacePart facePart, FacePoint[] facePoints) in face.FaceParts)
                        {
                            foreach (FacePoint facePoint in facePoints)
                                graphic.DrawEllipse(Pens.GreenYellow, facePoint.X - pointSize, facePoint.Y - pointSize, pointSize * 2, pointSize * 2);
                            if (facePart == FacePart.Chin)
                                continue;
                            if (facePoints.Length < 3)
                                continue;
                            x = (int)(from l in facePoints select l.X).Average();
                            y = (int)(from l in facePoints select l.Y).Average();
                            graphic.DrawEllipse(Pens.Purple, x - pointSize, y - pointSize, pointSize * 2, pointSize * 2);
                        }
                    }
                    image.Save(fileName, _ImageCodecInfo, _EncoderParameters);
                }
                if (saveRotated && face.FaceParts is not null)
                {
                    (_, α) = Shared.Models.Stateless.Methods.IFace.GetEyeα(face.FaceParts);
                    if (α is null)
                        continue;
                    using Image image = Image.FromFile(resizedFileHolder.FullName);
                    rotated = RotateBitmap(image, (float)α.Value);
                    if (rotated is not null)
                    {
                        rotated.Save(rotatedFileName, _ImageCodecInfo, _EncoderParameters);
                        rotated.Dispose();
                    }
                }
            }
            catch (Exception) { }
        }
    }

#pragma warning restore CA1416

    public void SaveFaceLandmarkImages(Configuration configuration, FilePath filePath, List<Tuple<string, DateTime>> subFileTuples, List<string> parseExceptions, MappingFromItem mappingFromItem, List<Shared.Models.Face> faces, bool saveRotated)
    {
        FileInfo fileInfo;
        bool check = false;
        const int pointSize = 2;
        FileInfo rotatedFileInfo;
        DateTime? dateTime = null;
        long ticks = DateTime.Now.Ticks;
        string deterministicHashCodeKey;
        bool updateDateWhenMatches = false;
        List<(Shared.Models.Face, string, string)> collection = [];
        string[] changesFrom = [nameof(A_Property), nameof(B_Metadata), nameof(C_Resize), nameof(D_Face)];
        List<DateTime> dateTimes = (from l in subFileTuples where changesFrom.Contains(l.Item1) select l.Item2).ToList();
        (_, int directoryIndex) = Shared.Models.Stateless.Methods.IPath.GetDirectoryNameAndIndex(_PropertyConfiguration, filePath);
        string directory = Path.Combine(_FileGroups[_PropertyConfiguration.ResultContent][directoryIndex], mappingFromItem.FilePath.NameWithoutExtension);
        bool directoryExists = Directory.Exists(directory);
        foreach (Shared.Models.Face face in faces)
        {
            if (face.FaceEncoding is null || face.Location is null || face.OutputResolution is null)
            {
                collection.Add(new(face, string.Empty, string.Empty));
                continue;
            }
            deterministicHashCodeKey = Shared.Models.Stateless.Methods.IMapping.GetDeterministicHashCodeKey(filePath, face.Location, Shared.Models.Stateless.ILocation.Digits, face.OutputResolution);
            fileInfo = new FileInfo(Path.Combine(directory, $"{deterministicHashCodeKey}{mappingFromItem.FilePath.ExtensionLowered}{_FileNameExtension}"));
            if (string.IsNullOrEmpty(fileInfo.DirectoryName))
                continue;
            rotatedFileInfo = new FileInfo(Path.Combine(fileInfo.DirectoryName, $"{deterministicHashCodeKey} - R{mappingFromItem.FilePath.ExtensionLowered}{_FileNameExtension}"));
            collection.Add(new(face, fileInfo.FullName, rotatedFileInfo.FullName));
            if (check)
                continue;
            else if (!directoryExists)
                check = true;
            else if (_OverrideForFaceLandmarkImages)
                check = true;
            else if (!fileInfo.Exists)
                check = true;
            else if (saveRotated && !rotatedFileInfo.Exists)
                check = true;
            else if (_CheckDFaceAndUpWriteDates && dateTimes.Count != 0 && dateTimes.Max() > fileInfo.LastWriteTime)
                check = true;
            if (check && !updateDateWhenMatches)
            {
                updateDateWhenMatches = dateTimes.Count != 0 && fileInfo.Exists && dateTimes.Max() > fileInfo.LastWriteTime;
                dateTime = !updateDateWhenMatches ? null : dateTimes.Max();
            }
        }
        if (check)
        {
            if (!directoryExists)
                _ = Directory.CreateDirectory(directory);
            SaveFaceParts(pointSize, mappingFromItem.ResizedFileHolder, saveRotated, collection);
        }
    }

#pragma warning disable CA1416

    private void SaveFaceLandmarkImage(MappingFromItem mappingFromItem, List<(Shared.Models.Face, FileHolder?, string, bool)> faceCollection, string fileName)
    {
        Pen pen;
        using Image image = Image.FromFile(mappingFromItem.ResizedFileHolder.FullName);
        using Graphics graphic = Graphics.FromImage(image);
        foreach ((Shared.Models.Face face, FileHolder? _, string _, bool _) in faceCollection)
        {
            if (face.FaceEncoding is null || face.Location is null || face.OutputResolution is null || face.FaceParts is null || face.FaceParts.Count == 0)
                continue;
            pen = face.Mapping?.MappingFromPerson is null ? Pens.Red : Pens.GreenYellow;
            try
            {
                foreach ((FacePart facePart, FacePoint[] facePoints) in face.FaceParts)
                {
                    for (int i = 0; i < facePoints.Length - 1; i++)
                        graphic.DrawLine(pen, new Point(facePoints[i].X, facePoints[i].Y), new Point(facePoints[i + 1].X, facePoints[i + 1].Y));
                }
            }
            catch (Exception) { }
        }
        image.Save(fileName, _ImageCodecInfo, _EncoderParameters);
    }

#pragma warning restore CA1416

    private static bool GetNotMapped(string facePartsCollectionDirectory, List<(Shared.Models.Face Face, FileHolder?, string, bool)> faceCollection)
    {
        bool results = false;
        string checkFile;
        foreach ((Shared.Models.Face face, FileHolder? fileHolder, string _, bool _) in faceCollection)
        {
            if (face.FaceEncoding is null || face.Location is null || face.OutputResolution is null)
                continue;
            if (fileHolder is not null)
            {
                checkFile = Path.Combine(facePartsCollectionDirectory, fileHolder.Name);
                if (face.Mapping?.MappingFromPerson is not null)
                {
                    if (File.Exists(checkFile))
                        File.Delete(checkFile);
                }
                else if (face.Mapping?.MappingFromFilterPre.InSkipCollection is not null && face.Mapping.MappingFromFilterPre.InSkipCollection.Value)
                {
                    if (File.Exists(checkFile))
                        File.Delete(checkFile);
                }
                else
                {
                    if (!results)
                        results = true;
                    if (!File.Exists(checkFile))
                        File.Copy(fileHolder.FullName, checkFile);
                }
            }
        }
        return results;
    }

    public void CopyFacesAndSaveFaceLandmarkImage(string facePartsCollectionDirectory, MappingFromItem mappingFromItem, List<(Shared.Models.Face Face, FileHolder?, string, bool)> faceCollection)
    {
        bool hasNotMapped = GetNotMapped(facePartsCollectionDirectory, faceCollection);
        string fileName = Path.Combine(facePartsCollectionDirectory, $"{mappingFromItem.FilePath.Name}{_FileNameExtension}");
        bool save = faceCollection.Any(l => l.Face.FaceEncoding is not null && l.Face.Location is not null && l.Face.OutputResolution is not null && l.Face.FaceParts is not null && l.Face.FaceParts.Count != 0);
        FileInfo fileInfo = new(fileName);
        if (save && (!fileInfo.Exists || new TimeSpan(DateTime.Now.Ticks - fileInfo.LastWriteTime.Ticks).TotalDays > 10))
        {
            SaveFaceLandmarkImage(mappingFromItem, faceCollection, fileName);
            fileInfo.Refresh();
        }
        if (!hasNotMapped && !fileInfo.Attributes.HasFlag(FileAttributes.Hidden) && (fileInfo.Exists || save))
            File.SetAttributes(fileName, FileAttributes.Hidden);
    }

}