using ScottPlot;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json.Nodes;

namespace Elwig.Helpers.Billing {
    public class Graph : ICloneable {

        public double[] DataX { get; set; }
        public double[] DataY { get; set; }

        public Graph(int minX, int maxX) {
            DataX = DataGen.Range(minX, maxX + 1);
            DataY = DataGen.Zeros(maxX - minX + 1);
        }

        public Graph(Dictionary<double, decimal> data, int minX, int maxX) {
            DataX = DataGen.Range(minX, maxX + 1);
            DataY = DataGen.Zeros(maxX - minX + 1);
            ParseGraphData(data, minX, maxX);
        }

        public Graph(double[] dataX, double[] dataY) {
            DataX = dataX;
            DataY = dataY;
        }

        public double GetOechsleAt(int index) {
            return DataX[index];
        }

        public void SetOechsleAt(int index, double oechsle) {
            DataX[index] = oechsle;
        }

        public void SetPriceAt(int index, double price) {
            DataY[index] = price;
        }

        public double GetPriceAt(int index) {
            return DataY[index];
        }

        private void ParseGraphData(Dictionary<double, decimal> graphPoints, int minX, int maxX) {
            if (graphPoints.Keys.Count < 1) {
                return;
            }

            var minKey = graphPoints.Keys.Order().First();
            var maxKey = graphPoints.Keys.OrderDescending().First();

            if (!graphPoints.ContainsKey(minX)) {
                graphPoints.Add(minX, graphPoints.GetValueOrDefault(minKey));
            }
            if (!graphPoints.ContainsKey(maxX)) {
                graphPoints.Add(maxX, graphPoints.GetValueOrDefault(maxKey));
            }

            var keys = graphPoints.Keys.Order().ToArray();

            for (int i = 0; i < keys.Length; i++) {
                decimal point1Value = graphPoints[keys[i]];
                if (i + 1 < keys.Length) {
                    decimal point2Value = graphPoints[keys[i + 1]];
                    if (point1Value == point2Value) {
                        for (int j = (int)(keys[i] - minX); j < keys[i + 1] - minX; j++) {
                            DataY[j] = (double)point1Value;
                        }
                    } else {
                        int steps = (int)Math.Abs(keys[i + 1] - keys[i]);
                        decimal step = (point2Value - point1Value) / steps;

                        DataY[(int)(keys[i] - minX)] = (double)point1Value;
                        DataY[(int)(keys[i + 1] - minX)] = (double)point2Value;

                        for (int j = (int)(keys[i] - minX); j < keys[i + 1] - minX - 1; j++) {
                            DataY[j + 1] = Math.Round(DataY[j] + (double)step, 4); // TODO richtig runden
                        }
                    }
                }
                else {
                    for (int j = (int)(keys[i] - minX); j < DataX.Length; j++) {
                        DataY[j] = (double)point1Value;
                    }
                }
            }
        }

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

        public void FlattenGraphLeft(int pointIndex) {
            FlattenGraph(0, pointIndex, DataY[pointIndex]);
        }

        public void FlattenGraphRight(int pointIndex) {
            FlattenGraph(pointIndex, DataY.Length - 1, DataY[pointIndex]);
        }

        private void LinearIncreaseGraph(int begin, int end, double inc) {
            for (int i = begin; i < end; i++) {
                DataY[i + 1] = Math.Round(DataY[i] + inc, 4); //TODO richtig runden
            }
        }

        public void LinearIncreaseGraphToEnd(int begin, double inc) {
            LinearIncreaseGraph(begin, DataY.Length - 1, inc);
        }

        public void InterpolateGraph(int firstPoint, int secondPoint) {
            int steps = Math.Abs(firstPoint - secondPoint);
            if (firstPoint == -1 || secondPoint == -1 || steps < 2) {
                return;
            }
            var (lowIndex, highIndex) = firstPoint < secondPoint ? (firstPoint, secondPoint) : (secondPoint, firstPoint);
            double step = (DataY[highIndex] - DataY[lowIndex]) / steps;

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

        public JsonNode ToJson(string mode) {
            if (DataY.Distinct().Count() == 1) {
                return JsonValue.Create(DataY[0]);
            }

            var data = new JsonObject();

            if (DataY[0] != DataY[1]) {
                data.Add(new KeyValuePair<string, JsonNode?>(DataX[0] + mode, Math.Round(DataY[0], 4)));
            }
            for (int i = 1; i < DataX.Length - 1; i++) {
                if (Math.Round(DataY[i] - DataY[i - 1], 10) != Math.Round(DataY[i + 1] - DataY[i], 10)) {
                    data.Add(new KeyValuePair<string, JsonNode?>(DataX[i] + mode, Math.Round(DataY[i], 4)));
                }
            }
            if (DataY[^1] != DataY[^2]) {
                data.Add(new KeyValuePair<string, JsonNode?>(DataX[^1] + mode, Math.Round(DataY[^1], 4)));
            }
            return data;
        }

        public object Clone() {
            return new Graph((double[])DataX.Clone(), (double[])DataY.Clone());
        }
    }
}