using System.Collections.ObjectModel;
using System.IO;
using System.Text.RegularExpressions;
using CommunityToolkit.Mvvm.ComponentModel;
using DicomViewer.Models;
using FellowOakDicom.Imaging;
using OxyPlot;
using OxyPlot.Series;

namespace DicomViewer.ViewModels;

public readonly record struct PixelInfo
{
    public string Name { get; init; }
    public string Value { get; init; }
}


internal class MainWindowViewModel : ObservableObject
{
    public DicomDataTuple? CurrentImage { get => _currentImage; private set => SetProperty(ref _currentImage, value); }
    public int CurrentIndex
    {
        get => _currentIndex;
        private set
        {
            SetProperty(ref _currentIndex, value);
            UpdateCurrentImage();
        }
    }
    public int MaxIndex { get => _maxIndex; private set => SetProperty(ref _maxIndex, value); }
    public string CurrentImageName
    {
        get => _currentImageName;
        set
        {
            SetProperty(ref _currentImageName, value);
            UpdateCurrentImage();
        }
    }
    public PlotModel CbfPlotModelModel { get => _cbfPlotModelModel; set => SetProperty(ref _cbfPlotModelModel, value); }
    public ObservableCollection<string> ImageList { get; } = [];
    public ObservableCollection<PixelInfo> PixelInfoList { get; } = [];
    public string CursorPosition { get => _cursorPosition; set => SetProperty(ref _cursorPosition, value); }

    private readonly Dictionary<string, List<DicomDataTuple>> _imageDictionary = new();
    private int _currentIndex;
    private int _maxIndex;
    private int _pldCount;
    private string _currentImageName = string.Empty;
    private string _cursorPosition = string.Empty;
    private PlotModel _cbfPlotModelModel = new();
    private DicomDataTuple? _currentImage;


    public void LoadData(string path)
    {
        CurrentImageName = "corr-cbf";
        _imageDictionary.Clear();
        ImageList.Clear();
        _pldCount = 0;

        try
        {
            //read from each sub folder
            foreach (string directory in Directory.GetDirectories(Path.Combine(path, "asl")))
            {
                string key = Path.GetFileName(directory);
                ImageList.Add(key);
                List<DicomDataTuple> imageList = LoadFromDir(directory);
                _imageDictionary.Add(key, imageList);

                if (Regex.IsMatch(key, @"cbf\d+"))
                    _pldCount++;
            }

            //read java temp
            string javaTempDir = Path.Combine(path, "java_temp", "reconstructed");
            if (Directory.Exists(javaTempDir))
            {
                foreach (string file in Directory.GetFiles(javaTempDir, "*.dcm"))
                {
                    string key = "j_" + Path.GetFileNameWithoutExtension(file);
                    ImageList.Add(key);
                    List<DicomDataTuple> imageList = LoadFromFile(file);
                    _imageDictionary.Add(key, imageList);
                }
            }

            MaxIndex = _imageDictionary.First().Value.Count;
            CurrentIndex = MaxIndex / 2;
        }
        catch (Exception e)
        {
            Console.WriteLine(e);
            throw;
        }
    }

    private static List<DicomDataTuple> LoadFromDir(string path)
    {
        string[] files = Directory.GetFiles(path);
        Array.Sort(files);
        List<DicomDataTuple> dataList = files.Select(file => new DicomDataTuple(file)).ToList();
        return dataList;
    }

    private static List<DicomDataTuple> LoadFromFile(string path)
    {
        DicomImage image = new(path);
        List<DicomDataTuple> dataList = Enumerable.Range(0, image.NumberOfFrames).Select(index => new DicomDataTuple(path, index)).ToList();
        return dataList;
    }
    
    public void UpdateCbfPlot(int x, int y)
    {
        try
        {
            //draw plot
            PlotModel model = new() { Title = "CBF Plot" };
            LineSeries cbfLine = new() { Title = "CBF", LineJoin = LineJoin.Bevel, MarkerType = MarkerType.Circle };
            for (int i = 1; i <= _pldCount; i++)
            {
                cbfLine.Points.Add(new DataPoint(i + 1, _imageDictionary[$"cbf{i}"][CurrentIndex - 1].GetPixel(x, y)));
            }
            model.Series.Add(cbfLine);

            //Siemens 5 
            if (_imageDictionary.ContainsKey("j_PLD1"))
            {
                LineSeries pldLine = new() { Title = "PLD", LineJoin = LineJoin.Bevel, MarkerType = MarkerType.Square };
                for (int i = 1; i <= _pldCount; i++)
                {
                    pldLine.Points.Add(new DataPoint(i + 1, _imageDictionary[$"j_PLD{i}"][CurrentIndex - 1].GetPixel(x, y)));
                }
                model.Series.Add(pldLine);
            }

            CbfPlotModelModel = model;

            //add all info
            PixelInfoList.Clear();
            foreach (KeyValuePair<string, List<DicomDataTuple>> pair in _imageDictionary)
            {
                string value = string.Empty;
                try
                {
                    value = pair.Value[CurrentIndex - 1].GetPixel(x, y).ToString("0.##");
                }
                catch (Exception e)
                {
                    Console.WriteLine(e);
                }
                PixelInfoList.Add(new PixelInfo { Name = pair.Key, Value = value });
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e);
        }
    }

    private void UpdateCurrentImage()
    {
        try
        {
            CurrentImage = _imageDictionary[CurrentImageName][CurrentIndex - 1];
        }
        catch (Exception e)
        {
            Console.WriteLine(e);
        }
    }

    public void NextImage()
    {
        if (CurrentIndex >= MaxIndex)
            return;

        CurrentIndex++;
    }

    public void PrevImage()
    {
        if (CurrentIndex <= 1)
            return;

        CurrentIndex--;
    }
}