#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion
using System;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;
using System.Windows.Forms.DataVisualization.Charting;
using HeuristicLab.MainForm;
using HeuristicLab.MainForm.WindowsForms;
using System.Collections.Generic;
using HeuristicLab.Problems.DataAnalysis.MultiVariate.TimeSeriesPrognosis.Symbolic;

namespace HeuristicLab.Problems.DataAnalysis.MultiVariate.TimeSeriesPrognosis.Views {
  [View("Symbolic Time Series Prognosis Line Chart View")]
  [Content(typeof(SymbolicTimeSeriesPrognosisSolution))]
  public partial class TimeSeriesPrognosisLineChartView : AsynchronousContentView {
    private const string TARGETVARIABLE_SERIES_NAME = "(target)";
    private const string ESTIMATEDVALUES_SERIES_NAME = "(estimated)";

    public new SymbolicTimeSeriesPrognosisSolution Content {
      get { return (SymbolicTimeSeriesPrognosisSolution)base.Content; }
      set { base.Content = value; }
    }

    public TimeSeriesPrognosisLineChartView()
      : base() {
      InitializeComponent();
      //configure axis
      this.chart.ChartAreas[0].CursorX.IsUserSelectionEnabled = true;
      this.chart.ChartAreas[0].AxisX.ScaleView.Zoomable = true;
      this.chart.ChartAreas[0].CursorX.Interval = 1;

      this.chart.ChartAreas[0].CursorY.IsUserSelectionEnabled = true;
      this.chart.ChartAreas[0].AxisY.ScaleView.Zoomable = true;
      this.chart.ChartAreas[0].CursorY.Interval = 0;
    }

    private void RedrawChart() {
      this.chart.Series.Clear();
      if (Content != null) {
        int selectedHorizonValue = Math.Min(Content.Horizon, Math.Max(1, (int)numericUpDown.Value));
        numericUpDown.Minimum = 1;
        numericUpDown.Maximum = Content.Horizon;
        numericUpDown.Value = selectedHorizonValue;
        List<string> targetVariables = Content.ProblemData.TargetVariables.CheckedItems.Select(x => x.Value.Value).ToList();
        // horizon=1 (t+0) =>  0 .. 10
        // horizon=2 (t+0..1) => -1 .. 9
        // horizon=3 (t+0..2) => -2 .. 8
        // ...
        // horizon=10 (t+0..9) => -9 .. 1
        int firstIndex = 1 - selectedHorizonValue;
        int lastIndex = Content.ProblemData.Dataset.Rows ;
        double[] nanVector =
          targetVariables
          .Select(x => double.NaN)
          .ToArray();
        IEnumerable<int> rows = Enumerable.Range(firstIndex, lastIndex );
        IEnumerable<IEnumerable<double[]>> values = from row in rows
                                                    let evaluate = string.IsNullOrEmpty(Content.ConditionalEvaluationVariable) ||
                                                                  (row > 0 && row < lastIndex &&
                                                                  Content.ProblemData.Dataset[Content.ConditionalEvaluationVariable, row + selectedHorizonValue - 1] > 0)
                                                    select evaluate ? Content.GetPrognosis(row) : Enumerable.Repeat(nanVector, Content.Horizon);

        for (int col = 0; col < targetVariables.Count; col++) {
          string targetVariable = targetVariables[col];
          this.chart.Series.Add(targetVariable + " " + TARGETVARIABLE_SERIES_NAME);
          this.chart.Series[targetVariable + " " + TARGETVARIABLE_SERIES_NAME].LegendText = targetVariable;
          this.chart.Series[targetVariable + " " + TARGETVARIABLE_SERIES_NAME].ChartType = SeriesChartType.FastLine;
          this.chart.Series[targetVariable + " " + TARGETVARIABLE_SERIES_NAME].Points.DataBindY(Content.ProblemData.Dataset.GetVariableValues(targetVariable));

          this.chart.Series.Add(targetVariable + " " + ESTIMATEDVALUES_SERIES_NAME);
          this.chart.Series[targetVariable + " " + ESTIMATEDVALUES_SERIES_NAME].LegendText = targetVariable + " " + ESTIMATEDVALUES_SERIES_NAME;
          this.chart.Series[targetVariable + " " + ESTIMATEDVALUES_SERIES_NAME].ChartType = SeriesChartType.FastLine;
          this.chart.Series[targetVariable + " " + ESTIMATEDVALUES_SERIES_NAME].Points.DataBindY(values.Select(x => x.ElementAt(selectedHorizonValue - 1)[col]).ToArray());
          this.chart.Series[targetVariable + " " + ESTIMATEDVALUES_SERIES_NAME].Tag = Content;
        }
        this.UpdateStripLines();
        UpdateCursorInterval();
      }
    }

    private void UpdateCursorInterval() {
      var allValues = (from series in this.chart.Series
                       from point in series.Points
                       select point.YValues[0])
                            .DefaultIfEmpty(1.0);
      double range = allValues.Max() - allValues.Min();
      double interestingValuesRange = Math.Min(Math.Max(range, 1.0), Math.Max(range, 1.0));
      double digits = (int)Math.Log10(interestingValuesRange) - 3;
      double yZoomInterval = Math.Max(Math.Pow(10, digits), 10E-5);
      this.chart.ChartAreas[0].CursorY.Interval = yZoomInterval;
    }

    #region events
    protected override void RegisterContentEvents() {
      base.RegisterContentEvents();
      Content.ProblemDataChanged += new EventHandler(Content_ProblemDataChanged);
    }
    protected override void DeregisterContentEvents() {
      base.DeregisterContentEvents();
      Content.ProblemDataChanged -= new EventHandler(Content_ProblemDataChanged);
    }

    private void Content_ProblemDataChanged(object sender, EventArgs e) {
      RedrawChart();
    }

    protected override void OnContentChanged() {
      base.OnContentChanged();
      RedrawChart();
    }

    #endregion

    private void UpdateStripLines() {
      this.chart.ChartAreas[0].AxisX.StripLines.Clear();
      this.CreateAndAddStripLine("Training", Color.FromArgb(20, Color.Green),
        Content.ProblemData.TrainingSamplesStart.Value,
        Content.ProblemData.TrainingSamplesEnd.Value);
      this.CreateAndAddStripLine("Test", Color.FromArgb(20, Color.Red),
        Content.ProblemData.TestSamplesStart.Value,
        Content.ProblemData.TestSamplesEnd.Value);
    }

    private void CreateAndAddStripLine(string title, Color c, int start, int end) {
      StripLine stripLine = new StripLine();
      stripLine.BackColor = c;
      stripLine.Text = title;
      stripLine.Font = new Font("Times New Roman", 12, FontStyle.Bold);
      stripLine.StripWidth = end - start;
      stripLine.IntervalOffset = start;
      this.chart.ChartAreas[0].AxisX.StripLines.Add(stripLine);
    }

    private void numericUpDown_ValueChanged(object sender, EventArgs e) {
      RedrawChart();
    }
  }
}