using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using Elwig.Helpers;
using Elwig.Helpers.Billing;
using Elwig.Models;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.ChangeTracking;
using ScottPlot;
using ScottPlot.Plottable;

namespace Elwig.Windows {
    public partial class ChartWindow : AdministrationWindow {

        private readonly int Year = 2021;
        private readonly int AvNr = 2;

        private ScatterPlot OechslePricePlotScatter;
        private MarkerPlot HighlightedPoint;
        private MarkerPlot PrimaryMarkedPoint;
        private MarkerPlot SecondaryMarkedPoint;
        private Tooltip Tooltip;

        private int LastHighlightedIndex = -1;
        private int HighlightedIndex = -1;
        private int PrimaryMarkedPointIndex = -1;
        private int SecondaryMarkedPointIndex = -1;
        private bool HoverChanged = false;
        private bool HoverActive = false;

        private const int MinOechsle = 50;
        private const int MaxOechsle = 140;

        private Graph? Graph;

        public ChartWindow() {
            InitializeComponent();

            ExemptInputs = new Control[] {
                GraphList, OechsleInput, PriceInput, FreeZoomInput, GradationLinesInput, TooltipInput
            };
        }

        private void Window_Loaded(object sender, RoutedEventArgs evt) {
            LockInputs();
            OechslePricePlot.IsEnabled = false;
        }

        private async Task RefreshGraphList() {
            await Context.PaymentVariants.LoadAsync();
            await RefreshGraphListQuery();
        }

        private async Task RefreshGraphListQuery(bool updateSort = false) {
            List<PaymentVar> paymentVars = await Context.PaymentVariants.Where(p => p.Year == Year && p.AvNr == AvNr).ToListAsync();

            if (paymentVars.Count != 1) {
                return;
            }

            PaymentVar paymentVar = paymentVars[0];
            var data = JsonNode.Parse(paymentVar.Data).AsObject();

            var auszahlungsSorten = data["AuszahlungSorten"]?.AsObject();
            if (auszahlungsSorten == null) {
                return;
            }

            var Graphs = auszahlungsSorten["Kurven"]?.AsArray();

            if (Graphs == null) {
                return;
            }

            List<Graph> GraphsList = new();

            int i = 1;
            foreach (var graph in Graphs) {
                GraphsList.Add(new Graph("Oe", i, graph?.AsObject(), ParseContracts(auszahlungsSorten, i - 1), 50, 140));
                i++;
            }

            ControlUtils.RenewItemsSource(GraphList, GraphsList, g => (g as Graph)?.Num);
            if (GraphsList.Count == 1) {
                GraphList.SelectedIndex = 0;
            }

            RefreshInputs();
        }

        private String ParseContracts(JsonObject auszahlungsSorten, int num) {
            List<string> contracts = new();

            foreach (var sorte in auszahlungsSorten) {
                if (sorte.Key == "Kurven") continue;
                foreach (var attribut in sorte.Value.AsObject()) {
                    foreach (var bindung in attribut.Value.AsObject()) {
                        if ((int)bindung.Value.AsValue() == num) {
                            contracts.Add($"{sorte.Key}/{attribut.Key}/{bindung.Key}");
                        }
                    }
                }
            }

            return string.Join("\n", contracts.ToArray());
        }

        private async Task<bool> RemoveGraph(int num) {
            List<PaymentVar> paymentVars = await Context.PaymentVariants.Where(p => p.Year == Year && p.AvNr == AvNr).ToListAsync();

            if (paymentVars.Count != 1) {
                return false;
            }

            PaymentVar paymentVar = paymentVars[0];
            var data = JsonNode.Parse(paymentVar.Data).AsObject();

            var auszahlungsSorten = data["AuszahlungSorten"]?.AsObject();
            if (auszahlungsSorten == null) {
                return false;
            }

            var Graphs = auszahlungsSorten["Kurven"]?.AsObject();
            if (Graphs == null) {
                return false;
            }

            int i = 1;
            foreach (var graph in Graphs) {
                if (i == num) {
                    Graphs.Remove(graph.Key);
                    break;
                }
                i++;
            }

            foreach (var sorte in auszahlungsSorten) {
                if (sorte.Key == "Kurven") continue;
                foreach (var attribut in sorte.Value.AsObject()) {
                    var bindungen = attribut.Value.AsObject();
                    foreach (var bindung in bindungen) {
                        int v = (int)bindung.Value;
                        if (v == num - 1) {
                            bindungen.Remove(bindung.Key);
                        } else if (v > num - 1) {
                            bindungen[bindung.Key] = v - 1;
                        }
                    }
                }
            }

            EntityEntry<PaymentVar>? tr = null;
            try {
                paymentVar.Data = data.ToString();
                tr = Context.Update(paymentVar);

                await Context.SaveChangesAsync();
            } catch (Exception exc) {
                if (tr != null) await tr.ReloadAsync();
                var str = "Der Eintrag konnte nicht in der Datenbank gelöscht werden!\n\n" + exc.Message;
                if (exc.InnerException != null) str += "\n\n" + exc.InnerException.Message;
                MessageBox.Show(str, "Graph löschen", MessageBoxButton.OK, MessageBoxImage.Error);
            }

            return true;
        }

        private void RefreshInputs(bool validate = false) {
            ResetPlot();
            ClearInputStates();
            if (GraphList.SelectedItem is Graph g) {
                EditButton.IsEnabled = true;
                DeleteButton.IsEnabled = true;
                EnableOptionButtons();
                FillInputs(g);
            } else {
                EditButton.IsEnabled = false;
                DeleteButton.IsEnabled = false;
                DisableOptionButtons();
                ClearOriginalValues();
                ClearInputs(validate);
                ClearInputStates();
            }
            GC.Collect();
        }

        private void FillInputs(Graph g) {
            ClearOriginalValues();

            Graph = (Graph)g.Clone();
            
            GraphNumberInput.Text = Graph.Num.ToString();
            if (Graph.Type == "oe") {
                OechsleGraphType_Input.IsChecked = true;
            } else if (Graph.Type == "kmw") {
                KmwGraphType_Input.IsChecked = true;
            }

            InitPlot();
            OechslePricePlot.IsEnabled = true;

            FinishInputFilling();
        }

        private void InitInputs() {
            GraphNumberInput.Text = (GraphList.Items.Count + 1).ToString();
            OechsleGraphType_Input.IsChecked = true;
            FinishInputFilling();
        }

        protected override async Task OnRenewContext() {
            await base.OnRenewContext();
            await RefreshGraphList();
        }

        private void InitPlot() {
            OechslePricePlotScatter = OechslePricePlot.Plot.AddScatter(Graph.DataX, Graph.DataY);

            OechslePricePlot.Configuration.DoubleClickBenchmark = false;
            OechslePricePlotScatter.LineColor = Color.Blue;
            OechslePricePlotScatter.MarkerColor = Color.Blue;
            OechslePricePlotScatter.MarkerSize = 9;

            //OechslePricePlot.Plot.XAxis.ManualTickSpacing(1);
            OechslePricePlot.Plot.YAxis.ManualTickSpacing(0.1);
            OechslePricePlot.Plot.SetAxisLimits(MinOechsle - 1, MaxOechsle + 1, -0.1, 2);
            
            OechslePricePlot.Plot.Layout(padding: 0);
            OechslePricePlot.Plot.XAxis2.Layout(padding: 0);
            OechslePricePlot.Plot.YAxis.Layout(padding: 0);
            OechslePricePlot.Plot.YAxis2.Layout(padding: 0);

            HighlightedPoint = OechslePricePlot.Plot.AddPoint(0, 0);
            HighlightedPoint.Color = Color.Red;
            HighlightedPoint.MarkerSize = 10;
            HighlightedPoint.MarkerShape = MarkerShape.openCircle;
            HighlightedPoint.IsVisible = false;

            PrimaryMarkedPoint = OechslePricePlot.Plot.AddPoint(0, 0);
            PrimaryMarkedPoint.Color = Color.Red;
            PrimaryMarkedPoint.MarkerSize = 6;
            PrimaryMarkedPoint.MarkerShape = MarkerShape.filledCircle;
            PrimaryMarkedPoint.IsVisible = false;

            SecondaryMarkedPoint = OechslePricePlot.Plot.AddPoint(0, 0);
            SecondaryMarkedPoint.Color = Color.Red;
            SecondaryMarkedPoint.MarkerSize = 6;
            SecondaryMarkedPoint.MarkerShape = MarkerShape.filledCircle;
            SecondaryMarkedPoint.IsVisible = false;

            OechslePricePlot.Refresh();

            RefreshFreeZoom();
            RefreshGradationLines();
        }

        private void ResetPlot() {
            Graph = null;
            PrimaryMarkedPointIndex = -1;
            OechslePricePlot.Plot.Remove(OechslePricePlotScatter);
            OechslePricePlot.Plot.Clear();
            OechslePricePlot.Reset();
            OechslePricePlot.Refresh();
        }

        private void ChangeMarker(MarkerPlot point, bool visible, double x = 0, double y = 0) {
            point.X = x;
            point.Y = y;
            point.IsVisible = visible;
        }

        private void FlattenGraph(int begin, int end, double value) {
            for (int i = begin; i <= end; i++) {
                Graph.DataY[i] = value;
            }
            OechslePricePlot.Render();
        }

        private void LinearIncreaseGraph(int begin, int end, double inc) {
            for (int i = begin; i < end; i++) {
                Graph.DataY[i + 1] = Graph.DataY[i] + inc;
            }
            OechslePricePlot.Render();
        }

        private void EnableActionButtons() {
            LeftFlatButton.IsEnabled = true; 
            RightFlatButton.IsEnabled = true; 
            LinearIncreaseButton.IsEnabled = true;
        }

        private void DisableActionButtons() {
            LeftFlatButton.IsEnabled = false;
            RightFlatButton.IsEnabled = false;
            InterpolateButton.IsEnabled = false;
            LinearIncreaseButton.IsEnabled = false;
        }

        private void FreeZoomInput_Changed(object sender, RoutedEventArgs evt) {
            RefreshFreeZoom();
        }

        private void RefreshFreeZoom() {
            if (FreeZoomInput.IsChecked == true) {
                UnlockZoom();
            } else {
                LockZoom();
            }
            OechslePricePlot.Refresh();
        }

        private void LockZoom() {
            OechslePricePlot.Plot.XAxis.SetBoundary(MinOechsle - 1, MaxOechsle + 1);
            OechslePricePlot.Plot.YAxis.SetBoundary(-0.1, 2);
            OechslePricePlot.Plot.XAxis.SetZoomOutLimit(MaxOechsle - MinOechsle + 2);
            OechslePricePlot.Plot.YAxis.SetZoomOutLimit(2.1);
            OechslePricePlot.Plot.SetAxisLimits(MinOechsle - 1, MaxOechsle + 1, -0.1, 2);
        }

        private void UnlockZoom() {
            OechslePricePlot.Plot.XAxis.SetBoundary();
            OechslePricePlot.Plot.YAxis.SetBoundary();
            OechslePricePlot.Plot.XAxis.SetZoomOutLimit((MaxOechsle - MinOechsle) * 1.5);
            OechslePricePlot.Plot.YAxis.SetZoomOutLimit(3.5);
        }

        private void EnableOptionButtons() {
            FreeZoomInput.IsEnabled = true;
            GradationLinesInput.IsEnabled = true;
            TooltipInput.IsEnabled = true;
        }

        private void DisableOptionButtons() {
            FreeZoomInput.IsEnabled = false;
            GradationLinesInput.IsEnabled = false;
            TooltipInput.IsEnabled = false;
        }

        private void GradationLinesInput_Changed(object sender, RoutedEventArgs evt) {
            RefreshGradationLines();
        }

        private void RefreshGradationLines() {
            if (GradationLinesInput.IsChecked == true) {
                ShowGradationLines();
                ShowLegend();
            } else {
                HideGradationLines();
                HideLegend();
            }
            OechslePricePlot.Refresh();
        }

        private void ShowGradationLines() {
            OechslePricePlot.Plot.AddVerticalLine(68, Color.Red, 2, label: "68 Oechsle (LDW)");
            OechslePricePlot.Plot.AddVerticalLine(73, Color.Orange, 2, label: "73 Oechsle (QUW)");
            OechslePricePlot.Plot.AddVerticalLine(84, Color.Green, 2, label: "84 Oechsle (KAB)");
        }

        private void HideGradationLines() {
            OechslePricePlot.Plot.Clear(typeof(VLine));
        }

        private void ShowLegend() {
            OechslePricePlot.Plot.Legend(true, Alignment.UpperRight);
        }

        private void HideLegend() {
            OechslePricePlot.Plot.Legend(false, Alignment.UpperRight);
        }

        private void OechsleInput_TextChanged(object sender, RoutedEventArgs evt) {
            IntegerInput_TextChanged(sender, evt);

            bool success = int.TryParse(OechsleInput.Text, out int oechsle);

            SecondaryMarkedPointIndex = -1;
            ChangeMarker(SecondaryMarkedPoint, false);

            if (success) {
                if (oechsle >= MinOechsle && oechsle <= MaxOechsle) {
                    PrimaryMarkedPointIndex = oechsle - MinOechsle;
                    ChangeMarker(PrimaryMarkedPoint, true, Graph.DataX[PrimaryMarkedPointIndex], Graph.DataY[PrimaryMarkedPointIndex]);

                    PriceInput.Text = Graph.DataY[PrimaryMarkedPointIndex].ToString();

                    if (IsEditing || IsCreating) EnableActionButtons();
                    OechslePricePlot.Render();
                    return;
                }
            }

            PrimaryMarkedPointIndex = -1;
            ChangeMarker(PrimaryMarkedPoint, false);
            DisableActionButtons();
            PriceInput.Text = "";
            OechslePricePlot.Render();
        }

        private void PriceInput_TextChanged(object sender, RoutedEventArgs evt) {
            if (PrimaryMarkedPointIndex != -1) {
                bool success = Double.TryParse(PriceInput.Text, out double price);

                if (success) {
                    Graph.DataY[PrimaryMarkedPointIndex] = price;
                    PrimaryMarkedPoint.Y = price;
                    SaveButton.IsEnabled = true;
                    ResetButton.IsEnabled = true;
                    OechslePricePlot.Refresh();
                }
            }
        }

        private void LeftFlatButton_Click(object sender, RoutedEventArgs evt) {
            if (PrimaryMarkedPointIndex == -1) {
                return;
            }
            FlattenGraph(0, PrimaryMarkedPointIndex, Graph.DataY[PrimaryMarkedPointIndex]);
            SaveButton.IsEnabled = true;
            ResetButton.IsEnabled = true;
        }

        private void RightFlatButton_Click(object sender, RoutedEventArgs evt) {
            if (PrimaryMarkedPointIndex == -1) {
                return;
            }
            FlattenGraph(PrimaryMarkedPointIndex, Graph.DataY.Length - 1, Graph.DataY[PrimaryMarkedPointIndex]);
            SaveButton.IsEnabled = true;
            ResetButton.IsEnabled = true;
        }

        private void InterpolateButton_Click(object sender, RoutedEventArgs evt) {
            int steps = Math.Abs(PrimaryMarkedPointIndex - SecondaryMarkedPointIndex);
            if (PrimaryMarkedPointIndex == -1 || SecondaryMarkedPointIndex == -1 || steps < 2) {
                return;
            }
            var (lowIndex, highIndex) = PrimaryMarkedPointIndex < SecondaryMarkedPointIndex ? (PrimaryMarkedPointIndex, SecondaryMarkedPointIndex): (SecondaryMarkedPointIndex, PrimaryMarkedPointIndex);

            double step = (Graph.DataY[highIndex] - Graph.DataY[lowIndex]) / steps;

            for (int i = lowIndex; i < highIndex - 1; i++) {
                Graph.DataY[i + 1] = Math.Round(Graph.DataY[i] + step, 4); // TODO richtig runden
            }
            SaveButton.IsEnabled = true;
            ResetButton.IsEnabled = true;
        }

        private void LinearIncreaseButton_Click(object sender, RoutedEventArgs e) { 
            if (PrimaryMarkedPointIndex == -1) {
                return;
            }
            double? priceIncrease = Utils.ShowLinearPriceIncreaseDialog();
            if (priceIncrease == null) {
                return;
            }
            LinearIncreaseGraph(PrimaryMarkedPointIndex, Graph.DataY.Length - 1, priceIncrease.Value);
            SaveButton.IsEnabled = true;
            ResetButton.IsEnabled = true;
        }

        private void OechslePricePlot_MouseDown(object sender, MouseEventArgs e) {
            if (!IsCreating && GraphList.SelectedItem == null) {
                return;
            }

            if (HoverActive) {
                if ((IsEditing || IsCreating) && Keyboard.IsKeyDown(Key.LeftCtrl)) {
                    if (PrimaryMarkedPointIndex == -1) {
                        return;
                    }
                    SecondaryMarkedPointIndex = HighlightedIndex;
                    ChangeMarker(SecondaryMarkedPoint, true, Graph.DataX[SecondaryMarkedPointIndex], Graph.DataY[SecondaryMarkedPointIndex]);

                    InterpolateButton.IsEnabled = true;

                    return;
                }

                PrimaryMarkedPointIndex = HighlightedIndex;
                ChangeMarker(PrimaryMarkedPoint, true, Graph.DataX[PrimaryMarkedPointIndex], Graph.DataY[PrimaryMarkedPointIndex]);

                OechsleInput.Text = Graph.DataX[HighlightedIndex].ToString();
                PriceInput.Text = Graph.DataY[HighlightedIndex].ToString();

                if (IsEditing || IsCreating) {
                    EnableActionButtons();
                }
            } else {
                PrimaryMarkedPointIndex = -1;
                SecondaryMarkedPointIndex = -1;
                ChangeMarker(PrimaryMarkedPoint, false);
                ChangeMarker(SecondaryMarkedPoint, false);

                OechsleInput.Text = "";
                PriceInput.Text = "";

                DisableActionButtons();
            }
        }

        private void OechslePricePlot_MouseMove(object sender, MouseEventArgs e) {
            if (!IsCreating && GraphList.SelectedItem == null) {
                return;
            }

            (double mouseCoordX, double mouseCoordY) = OechslePricePlot.GetMouseCoordinates();
            double xyRatio = OechslePricePlot.Plot.XAxis.Dims.PxPerUnit / OechslePricePlot.Plot.YAxis.Dims.PxPerUnit;
            (double pointX, double pointY, int pointIndex) = OechslePricePlotScatter.GetPointNearest(mouseCoordX, mouseCoordY, xyRatio);

            (double mousePixelX, double mousePixelY) = OechslePricePlot.GetMousePixel();
            (double pointPixelX, double pointPixelY) = OechslePricePlot.Plot.GetPixel(pointX, pointY);

            HighlightedIndex = LastHighlightedIndex;

            if (Math.Abs(mousePixelX - pointPixelX) < 3 && Math.Abs(mousePixelY - pointPixelY) < 3) {
                ChangeMarker(HighlightedPoint, true, pointX, pointY);
                HighlightedPoint.IsVisible = true;
                HoverChanged = true ^ HoverActive;
                HoverActive = true;
            } else {
                ChangeMarker(HighlightedPoint, false);
                HoverChanged= false ^ HoverActive;
                HoverActive= false;
                OechslePricePlot.Plot.Remove(Tooltip);
                OechslePricePlot.Render();
            }

            if (LastHighlightedIndex != HighlightedIndex || HoverChanged) {
                OechslePricePlot.Plot.Remove(Tooltip);
                if (TooltipInput.IsChecked == true) {
                    Tooltip = OechslePricePlot.Plot.AddTooltip($"Oechsle: {pointX:N2}, Preis: {Math.Round(pointY, 4)})", pointX, pointY);
                }
                LastHighlightedIndex = pointIndex;
                HoverChanged = false;
                OechslePricePlot.Render();
            }
        }

        override protected void UpdateButtons() {
            if (!IsEditing && !IsCreating) return;
            bool ch = HasChanged, v = IsValid;
        }

        private void DisableNewEditDeleteButtons() {
            NewButton.IsEnabled = false;
            EditButton.IsEnabled = false;
            DeleteButton.IsEnabled = false;
        }

        private void EnableNewEditDeleteButtons() {
            NewButton.IsEnabled = true;
            EditButton.IsEnabled = GraphList.SelectedItem != null;
            DeleteButton.IsEnabled = GraphList.SelectedItem != null;
        }

        private void ShowSaveResetCancelButtons() {
            SaveButton.IsEnabled = false;
            ResetButton.IsEnabled = false;
            CancelButton.IsEnabled = true;
            SaveButton.Visibility = Visibility.Visible;
            ResetButton.Visibility = Visibility.Visible;
            CancelButton.Visibility = Visibility.Visible;
        }

        private void HideSaveResetCancelButtons() {
            SaveButton.IsEnabled = false;
            ResetButton.IsEnabled = false;
            CancelButton.IsEnabled = false;
            SaveButton.Visibility = Visibility.Hidden;
            ResetButton.Visibility = Visibility.Hidden;
            CancelButton.Visibility = Visibility.Hidden;
        }
        private void ShowNewEditDeleteButtons() {
            EnableNewEditDeleteButtons();
            NewButton.Visibility = Visibility.Visible;
            EditButton.Visibility = Visibility.Visible;
            DeleteButton.Visibility = Visibility.Visible;
        }

        private void HideNewEditDeleteButtons() {
            DisableNewEditDeleteButtons();
            NewButton.Visibility = Visibility.Hidden;
            EditButton.Visibility = Visibility.Hidden;
            DeleteButton.Visibility = Visibility.Hidden;
        }

        private void NewButton_Click(object sender, RoutedEventArgs e) {
            IsCreating = true;
            GraphList.IsEnabled = false;
            GraphList.SelectedItem = null;
            HideNewEditDeleteButtons();
            ShowSaveResetCancelButtons();
            UnlockInputs();
            PriceInput.IsReadOnly = false;
            OechsleInput.IsReadOnly = false;
            InitInputs();
            FillInputs(new Graph(GraphList.Items.Count + 1, MinOechsle, MaxOechsle));
            EnableOptionButtons();
        }

        private void EditButton_Click(object sender, RoutedEventArgs e) {
            if (GraphList.SelectedItem == null) {
                return;
            }

            IsEditing = true;
            GraphList.IsEnabled = false;

            HideNewEditDeleteButtons();
            ShowSaveResetCancelButtons();
            UnlockInputs();
            PriceInput.IsReadOnly = false;
            OechsleInput.IsReadOnly = false;
            if (PrimaryMarkedPointIndex != -1) EnableActionButtons();
        }

        private async void DeleteButton_Click(object sender, RoutedEventArgs e) {
            Graph g = (Graph)GraphList.SelectedItem;
            if (g == null) return;

            var r = MessageBox.Show(
                $"Soll der Graph {g.Num} (verwendet in folgenden Verträgen: {g.Contracts}) wirklich unwiderruflich gelöscht werden?",
                "Graph löschen", MessageBoxButton.YesNo, MessageBoxImage.Warning, MessageBoxResult.No);
            if (r == MessageBoxResult.Yes) {
                bool success = await RemoveGraph(g.Num);
                if (!success) {
                    MessageBox.Show("Der Graph konnte nicht gelöscht werden", "Graph löschen", MessageBoxButton.OK, MessageBoxImage.Error);
                }
                await RefreshGraphList();
            }
        }


        private async void SaveButton_Click(object sender, RoutedEventArgs e) {
            int? index = await UpdateGraph(Graph);
            if (index == null) {
                MessageBox.Show("Der Graph konnte nicht gespeichert werden", "Graph speichern", MessageBoxButton.OK, MessageBoxImage.Error);
            }
            IsEditing = false;
            IsCreating = false;
            GraphList.IsEnabled = true;
            HideSaveResetCancelButtons();
            ShowNewEditDeleteButtons();
            LockInputs();
            PriceInput.IsReadOnly = true;
            OechsleInput.IsReadOnly = true;
            await RefreshGraphList();
            GraphList.SelectedIndex = index.Value;
        }

        private async Task<int?> UpdateGraph(Graph g) {
            List<PaymentVar> paymentVars = await Context.PaymentVariants.Where(p => p.Year == Year && p.AvNr == AvNr).ToListAsync();

            if (paymentVars.Count != 1) {
                return null;
            }

            PaymentVar paymentVar = paymentVars[0];
            var data = JsonNode.Parse(paymentVar.Data).AsObject();

            var auszahlungsSorten = data["AuszahlungSorten"];
            if (auszahlungsSorten == null) {
                return null;
            }

            var Graphs = auszahlungsSorten["Kurven"].AsArray();
            if (Graphs == null) {
                return null;
            }

            if (IsEditing) {
                Graphs[g.Num - 1] = g.ToJson();
            } else if(IsCreating) {
                Graphs.Add(g.ToJson());
            } else {
                return null;
            }

            EntityEntry<PaymentVar>? tr = null;
            try {
                paymentVar.Data = data.ToString();
                tr = Context.Update(paymentVar);

                await Context.SaveChangesAsync();
            } catch (Exception exc) {
                if (tr != null) await tr.ReloadAsync();
                var str = "Der Eintrag konnte nicht in der Datenbank gelöscht werden!\n\n" + exc.Message;
                if (exc.InnerException != null) str += "\n\n" + exc.InnerException.Message;
                MessageBox.Show(str, "Graph löschen", MessageBoxButton.OK, MessageBoxImage.Error);
            }

            return g.Num - 1;
        }

        private void ResetButton_Click(object sender, RoutedEventArgs e) {
            if (IsEditing) {
                RefreshInputs();
            } else if (IsCreating) {
                InitInputs();
            }
            UpdateButtons();
        }

        private void CancelButton_Click(object sender, RoutedEventArgs e) {
            IsEditing = false;
            IsCreating = false;
            GraphList.IsEnabled = true;
            HideSaveResetCancelButtons();
            ShowNewEditDeleteButtons();
            DisableActionButtons();
            RefreshInputs();
            PriceInput.Text = "";
            OechsleInput.Text = "";
            ClearInputStates();
            LockInputs();
            PriceInput.IsReadOnly = true;
            OechsleInput.IsReadOnly = true;
        }

        private void GraphList_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e) {
            RefreshInputs();

            //var x = OechslePricePlot.Plot.GetPlottables().OfType<ScatterPlot>();
            //MessageBox.Show($"SelectionChanged\nLength: {x.ToList().Count}, Ys: {string.Join(", ", ((ScatterPlot)x.First()).Ys)}");
        }

        private void PriceInput_LostFocus(object sender, RoutedEventArgs e) {

        }

        private void OechsleInput_LostFocus(object sender, RoutedEventArgs e) {

        }

        private void GraphNumberInput_TextChanged(object sender, TextChangedEventArgs e) {

        }

        private void GraphNumberInput_LostFocus(object sender, RoutedEventArgs e) {

        }
    }
}