#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2011 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.ComponentModel;
using System.Drawing;
using System.Globalization;
using System.Windows.Forms;
using HeuristicLab.Core.Views;
using HeuristicLab.Data;
using HeuristicLab.Encodings.PermutationEncoding;
using HeuristicLab.MainForm;

namespace HeuristicLab.Problems.QuadraticAssignment.Views {
  /// <summary>
  /// The base class for visual representations of a path tour for a TSP.
  /// </summary>
  [View("QAPAssignment View")]
  [Content(typeof(QAPAssignment), true)]
  public sealed partial class QAPAssignmentView : ItemView {
    public new QAPAssignment Content {
      get { return (QAPAssignment)base.Content; }
      set { base.Content = value; }
    }

    /// <summary>
    /// Initializes a new instance of <see cref="PathTSPTourView"/>.
    /// </summary>
    public QAPAssignmentView() {
      InitializeComponent();
    }

    protected override void DeregisterContentEvents() {
      Content.PropertyChanged -= new PropertyChangedEventHandler(Content_PropertyChanged);
      base.DeregisterContentEvents();
    }
    protected override void RegisterContentEvents() {
      base.RegisterContentEvents();
      Content.PropertyChanged += new PropertyChangedEventHandler(Content_PropertyChanged);
    }

    protected override void OnContentChanged() {
      base.OnContentChanged();
      if (Content == null) {
        qualityViewHost.Content = null;
        pictureBox.Image = null;
        assignmentViewHost.Content = null;
      } else {
        qualityViewHost.Content = Content.Quality;
        GenerateImage();
        assignmentViewHost.Content = Content.Assignment;
      }
    }

    protected override void SetEnabledStateOfControls() {
      base.SetEnabledStateOfControls();
      qualityGroupBox.Enabled = Content != null;
      pictureBox.Enabled = Content != null;
      assignmentGroupBox.Enabled = Content != null;
    }

    private void GenerateImage() {
      if ((pictureBox.Width > 0) && (pictureBox.Height > 0)) {
        if (Content == null) {
          pictureBox.Image = null;
        } else {
          bool drawDistances = false;
          DoubleMatrix coordinates = Content.Coordinates;
          DoubleMatrix distances = Content.Distances;
          if ((coordinates == null || coordinates.Rows == 0)
            && (distances == null || distances.Rows == 0)) return;
          else if ((coordinates == null || coordinates.Rows == 0)
            && Content.ViewCoordinates == null) {
            coordinates = new DoubleMatrix(distances.Rows, 2);
            int columns = (int)Math.Ceiling(Math.Sqrt(coordinates.Rows));
            int x = 0, y = 0;
            for (int i = 0; i < coordinates.Rows; i++) {
              coordinates[i, 0] = 10 * x;
              coordinates[i, 1] = 10 * y;
              if (++x > columns) {
                y++;
                x = 0;
              }
            }
            Content.ViewCoordinates = coordinates;
            drawDistances = true;
          } else if ((coordinates == null || coordinates.Rows == 0)
            && Content.ViewCoordinates != null) {
            coordinates = Content.ViewCoordinates;
            drawDistances = true;
          }

          DoubleMatrix weights = Content.Weights;
          Permutation permutation = Content.Assignment;
          Bitmap bitmap = new Bitmap(pictureBox.Width, pictureBox.Height);

          if ((coordinates != null) && (coordinates.Rows > 0) && (coordinates.Columns == 2)) {
            double xMin = double.MaxValue, yMin = double.MaxValue, xMax = double.MinValue, yMax = double.MinValue;
            for (int i = 0; i < coordinates.Rows; i++) {
              if (xMin > coordinates[i, 0]) xMin = coordinates[i, 0];
              if (yMin > coordinates[i, 1]) yMin = coordinates[i, 1];
              if (xMax < coordinates[i, 0]) xMax = coordinates[i, 0];
              if (yMax < coordinates[i, 1]) yMax = coordinates[i, 1];
            }

            int border = 20;
            double xStep = xMax != xMin ? (pictureBox.Width - 2 * border) / (xMax - xMin) : 1;
            double yStep = yMax != yMin ? (pictureBox.Height - 2 * border) / (yMax - yMin) : 1;

            Point[] points = new Point[coordinates.Rows];
            for (int i = 0; i < coordinates.Rows; i++)
              points[i] = new Point(border + ((int)((coordinates[i, 0] - xMin) * xStep)),
                                    bitmap.Height - (border + ((int)((coordinates[i, 1] - yMin) * yStep))));

            using (Graphics graphics = Graphics.FromImage(bitmap)) {
              if ((permutation != null) && (permutation.Length == coordinates.Rows) && (permutation.Validate())) {
                for (int i = 0; i < permutation.Length; i++) {
                  for (int j = 0; j < permutation.Length; j++) {
                    if (i != j && weights[i, j] > 0) {
                      graphics.DrawLine(Pens.Black, points[permutation[i]], points[permutation[j]]);
                      float midX = ((points[permutation[i]].X + points[permutation[j]].X) / 2.0f) + 5;
                      float midY = ((points[permutation[i]].Y + points[permutation[j]].Y) / 2.0f) - 5;
                      graphics.DrawString(weights[i, j].ToString(CultureInfo.InvariantCulture.NumberFormat), Font, Brushes.Black, midX, midY);
                    }
                  }
                }
              }
              for (int i = 0; i < points.Length; i++)
                graphics.FillRectangle(Brushes.Red, points[i].X - 2, points[i].Y - 2, 6, 6);
            }
          }
          pictureBox.Image = bitmap;
        }
      }
    }

    private void Content_PropertyChanged(object sender, PropertyChangedEventArgs e) {
      if (InvokeRequired)
        Invoke(new PropertyChangedEventHandler(Content_PropertyChanged), sender, e);
      else {
        switch (e.PropertyName) {
          case "Coordinates":
          case "Distances":
          case "Weights":
            GenerateImage();
            break;
          case "Permutation":
            GenerateImage();
            assignmentViewHost.Content = Content.Assignment;
            break;
          case "Quality":
            break;
          default:
            break;
        }
      }
    }

    private void pictureBox_SizeChanged(object sender, EventArgs e) {
      GenerateImage();
    }
  }
}