#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2016 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.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Linq;
using System.Windows.Forms;

namespace HeuristicLab.Visualization {
  public partial class ChartControl : UserControl {
    protected Bitmap Picture;
    protected bool RenderingRequired;
    protected Dictionary<Type, ChartMode> Modes = new Dictionary<Type, ChartMode>();
    protected Stack<ChartMode> ModeStack = new Stack<ChartMode>();
    protected List<ChartMode.Shortcut> Shortcuts = new List<ChartMode.Shortcut>();
    protected ChartMode.Shortcut ActiveShortcut;

    protected bool SuppressEvents { get; set; }
    private bool SuppressRender { get; set; }

    public bool ShowToolBar {
      get { return !splitContainer.Panel1Collapsed; }
      set { splitContainer.Panel1Collapsed = !value; }
    }

    private IChart chart;
    public IChart Chart {
      get { return chart; }
      protected set {
        if (chart != null) DeregisterChartEvents(chart);
        chart = value;
        chart.Enabled = Enabled;
        pictureBox.Enabled = Enabled;
        if (chart != null) RegisterChartEvents(chart);
      }
    }

    private ChartMode mode;
    private ChartMode defaultMode;
    public ChartMode Mode {
      get { return mode; }
      set {
        if (mode == value) return;
        mode = value;
        if (defaultMode == null) defaultMode = mode;
        if (mode == null) mode = defaultMode;
        SetModeButtonCheckedState();
        SetModeMenuItemCheckedState();
        SetPictureBoxCursor(GetPictureBoxCursor());
        OnModeChanged();
        if (chart != null) {
          GenerateImage();
        }
      }
    }

    public SmoothingMode SmoothingMode { get; set; }

    public bool ScaleOnResize { get; set; }

    public bool IsRenderingPaused { get { return SuppressRender; } }

    public ChartControl() : this(null) { }
    public ChartControl(IChart defaultChart) {
      InitializeComponent();
      ScaleOnResize = true;
      Chart = defaultChart ?? new Chart(0, 0, Width, Height);
    }

    public void AddChartModes(params ChartMode[] chartModes) {
      foreach (var chartMode in chartModes) {
        Modes.Add(chartMode.GetType(), chartMode);
        foreach (var shortcut in chartMode.Shortcuts)
          Shortcuts.Add(shortcut);
      }

      ReloadModeToolBar();
      ReloadModeContextMenu();
    }

    public void SetTempChartMode(ChartMode chartMode) {
      if (Mode == chartMode) return;

      ModeStack.Push(mode);
      Mode = chartMode;
    }

    public void ResetTempChartMode() {
      if (ModeStack.Any())
        Mode = ModeStack.Pop();
    }

    public void SuspendRendering() {
      SuppressRender = true;
    }

    public void ResumeRendering() {
      SuppressRender = false;
      if (Chart != null) GenerateImage();
    }

    public void RefreshPicture() {
      pictureBox.Refresh();
    }

    public void UpdatePicture() {
      pictureBox.Update();
    }

    public Graphics CreatePictureGraphics() {
      return pictureBox.CreateGraphics();
    }

    public System.Drawing.Rectangle GetPictureBounds() {
      return pictureBox.Bounds;
    }

    protected virtual void ReloadModeToolBar() {
      splitContainer.Panel1.Controls.Clear();

      var chartModes = Modes.Values.ToList();
      for (int i = 0; i < chartModes.Count; i++) {
        var chartMode = chartModes[i];
        var rb = CreateChartModeRadioButton(chartMode);
        rb.Location = new Point(3, 3 + i * (rb.Height + rb.Margin.Vertical));
        rb.TabIndex = i;
        toolTip.SetToolTip(rb, chartMode.ToolTipText);
        splitContainer.Panel1.Controls.Add(rb);
      }

      SetModeButtonCheckedState();
    }

    protected virtual void ReloadModeContextMenu() {
      modeToolStripMenuItem.DropDownItems.Clear();

      foreach (var chartMode in Modes.Values) {
        var mi = CreateChartModeMenuItem(chartMode);
        modeToolStripMenuItem.DropDownItems.Add(mi);
      }

      SetModeMenuItemCheckedState();
    }

    protected virtual void SetModeButtonCheckedState() {
      foreach (var rb in splitContainer.Panel1.Controls.OfType<RadioButton>())
        rb.Checked = rb.Tag == Mode;
    }

    protected virtual void SetModeMenuItemCheckedState() {
      foreach (var mi in modeToolStripMenuItem.DropDownItems.OfType<ToolStripMenuItem>())
        mi.Checked = mi.Tag == Mode;
    }

    protected virtual void SetPictureBoxCursor(Cursor cursor) {
      if (pictureBox.Cursor != cursor) pictureBox.Cursor = cursor;
    }

    protected virtual Cursor GetPictureBoxCursor() {
      return mode != null ? mode.Cursor : null;
    }

    protected virtual void RegisterChartEvents(IChart chart) {
      chart.RedrawRequired += ChartOnUpdateRequired;
    }

    protected virtual void DeregisterChartEvents(IChart chart) {
      chart.RedrawRequired -= ChartOnUpdateRequired;
    }

    protected virtual void ChartOnUpdateRequired(object sender, EventArgs e) {
      if (SuppressRender) return;
      GenerateImage();
    }

    #region PictureBox Events
    protected virtual void PictureBoxOnSizeChanged(object sender, EventArgs e) {
      if (Chart == null) return;
      if (ScaleOnResize) {
        if ((pictureBox.Width > 0) && (pictureBox.Height > 0) && (Chart != null)) {
          var point = Chart.TransformPixelToWorld(new Point(pictureBox.Width, Chart.SizeInPixels.Height - pictureBox.Height));
          var diff = Chart.UpperRight - point;
          Chart.SetPosition(new PointD(Chart.LowerLeft.X, Chart.LowerLeft.Y),
                            new PointD(Chart.UpperRight.X - diff.DX, Chart.UpperRight.Y - diff.DY));
        }
      }
      GenerateImage();
    }

    protected virtual void PictureBoxOnVisibleChanged(object sender, EventArgs e) {
      if (pictureBox.Visible && RenderingRequired) GenerateImage();
    }

    protected virtual void PictureBoxOnMouseClick(object sender, MouseEventArgs e) {
      if (mode != null)
        mode.HandleOnMouseClick(sender, e);
    }

    protected virtual void PictureBoxOnMouseDoubleClick(object sender, MouseEventArgs e) {
      if (mode != null)
        mode.HandleOnMouseDoubleClick(sender, e);
    }

    protected virtual void OnKeyDown(object sender, KeyEventArgs e) {
      if (mode != null) {
        mode.HandleOnKeyDown(sender, e);

        if (e.Handled || ActiveShortcut != null) return;

        foreach (var shortcut in Shortcuts) {
          if (e.KeyCode == shortcut.Key && e.Modifiers == shortcut.Modifiers) {
            ActiveShortcut = shortcut;
            var downAction = shortcut.DownAction;
            if (downAction != null) downAction();
            e.Handled = true;
            break;
          }
        }
      }
    }

    protected virtual void OnKeyUp(object sender, KeyEventArgs e) {
      if (mode != null) {
        mode.HandleOnKeyUp(sender, e);

        if (e.Handled || ActiveShortcut == null) return;

        var modifiers = new List<Keys>(from key in Enum.GetValues(typeof(Keys)).Cast<Keys>()
                                       where e.Modifiers.HasFlag(key)
                                       select key);

        if (ActiveShortcut.Key == e.KeyCode || ActiveShortcut.GetModifiers().Except(modifiers).Any()) {
          var upAction = ActiveShortcut.UpAction;
          if (upAction != null) upAction();
          ActiveShortcut = null;
          e.Handled = true;
        }
      }
    }

    protected virtual void PictureBoxOnMouseWheel(object sender, MouseEventArgs e) {
      if (mode != null)
        mode.HandleOnMouseWheel(sender, e);
    }

    protected virtual void PictureBoxOnMouseDown(object sender, MouseEventArgs e) {
      if (mode != null)
        mode.HandleOnMouseDown(sender, e);
    }

    protected virtual void PictureBoxOnMouseUp(object sender, MouseEventArgs e) {
      if (mode != null)
        mode.HandleOnMouseUp(sender, e);

      if (Chart == null) return;

      if (e.Button == MouseButtons.Right) {
        propertiesToolStripMenuItem.Enabled = Chart.Group.SelectedPrimitives.Count() == 1;
        oneLayerUpToolStripMenuItem.Enabled = Chart.Group.SelectedPrimitives.Count() == 1;
        oneLayerDownToolStripMenuItem.Enabled = Chart.Group.SelectedPrimitives.Count() == 1;
        intoForegroundToolStripMenuItem.Enabled = Chart.Group.SelectedPrimitives.Count() == 1;
        intoBackgroundToolStripMenuItem.Enabled = Chart.Group.SelectedPrimitives.Count() == 1;
      }
    }

    protected virtual void PictureBoxOnMouseMove(object sender, MouseEventArgs e) {
      if (InvokeRequired) {
        Invoke((Action<object, MouseEventArgs>)PictureBoxOnMouseMove, sender, e);
      } else {
        var toolTipText = Chart.GetToolTipText(e.Location);
        if (toolTip.GetToolTip(pictureBox) != toolTipText) toolTip.SetToolTip(pictureBox, toolTipText);

        if (mode != null)
          mode.HandleOnMouseMove(sender, e);

        SetPictureBoxCursor(GetPictureBoxCursor());
      }
    }

    protected virtual void PictureBoxOnMouseEnter(object sender, EventArgs e) {
      if (InvokeRequired) {
        Invoke((Action<object, MouseEventArgs>)PictureBoxOnMouseEnter, sender, e);
        return;
      }
      if (!Focused) pictureBox.Focus();

      if (mode != null)
        mode.HandleOnMouseEnter(sender, e);
    }

    protected virtual void PictureBoxOnMouseLeave(object sender, EventArgs e) {
      if (mode != null)
        mode.HandleOnMouseLeave(sender, e);
    }

    protected virtual void PictureBoxOnClick(object sender, EventArgs e) {
      if (InvokeRequired) {
        Invoke((Action<object, MouseEventArgs>)PictureBoxOnClick, sender, e);
        return;
      }
      if (!Focused) pictureBox.Focus();

      if (mode != null)
        mode.HandleOnClick(sender, e);
    }
    #endregion

    protected virtual void PictureBoxContextMenuStripOnOpening(object sender, CancelEventArgs e) { }

    protected virtual void oneLayerUpToolStripMenuItem_Click(object sender, EventArgs e) {
      if (Chart == null) return;
      if (Chart.Group.SelectedPrimitives.Count() == 1) {
        Chart.OneLayerUp(Chart.Group.SelectedPrimitives.First());
      }
    }
    protected virtual void oneLayerDownToolStripMenuItem_Click(object sender, EventArgs e) {
      if (Chart == null) return;
      if (Chart.Group.SelectedPrimitives.Count() == 1) {
        Chart.OneLayerDown(Chart.Group.SelectedPrimitives.First());
      }
    }
    protected virtual void intoForegroundToolStripMenuItem_Click(object sender, EventArgs e) {
      if (Chart == null) return;
      if (Chart.Group.SelectedPrimitives.Count() == 1) {
        Chart.IntoForeground(Chart.Group.SelectedPrimitives.First());
      }
    }
    protected virtual void intoBackgroundToolStripMenuItem_Click(object sender, EventArgs e) {
      if (Chart == null) return;
      if (Chart.Group.SelectedPrimitives.Count() == 1) {
        Chart.IntoBackground(Chart.Group.SelectedPrimitives.First());
      }
    }
    protected virtual void propertiesToolStripMenuItem_Click(object sender, EventArgs e) {
      if (Chart == null) return;
      if (Chart.Group.SelectedPrimitives.Count() == 1) {
        using (var dialog = new PropertiesDialog(Chart.Group.SelectedPrimitives.First())) {
          dialog.ShowDialog(this);
        }
      }
    }
    protected virtual void saveImageToolStripMenuItem_Click(object sender, EventArgs e) {
      if (Picture == null) return;

      if (saveFileDialog.ShowDialog() == DialogResult.OK) {
        var format = ImageFormat.Bmp;
        var filename = saveFileDialog.FileName.ToLower();
        if (filename.EndsWith("emf")) {
          using (var g1 = Graphics.FromImage(Picture)) {
            var rectangle = new System.Drawing.Rectangle(0, 0, Picture.Width, Picture.Height);
            using (var metafile = new Metafile(filename, g1.GetHdc(), rectangle, MetafileFrameUnit.Pixel, EmfType.EmfPlusDual))
            using (var g2 = Graphics.FromImage(metafile))
              Chart.Render(g2, pictureBox.Width, pictureBox.Height);
          }
        } else {
          using (var graphics = Graphics.FromImage(Picture))
            Chart.Render(graphics, Picture.Width, Picture.Height);

          if (filename.EndsWith("jpg")) {
            format = ImageFormat.Jpeg;
          } else if (filename.EndsWith("gif")) {
            format = ImageFormat.Gif;
          } else if (filename.EndsWith("png")) {
            format = ImageFormat.Png;
          } else if (filename.EndsWith("tif")) {
            format = ImageFormat.Tiff;
          }

          Picture.Save(saveFileDialog.FileName, format);
        }
      }
    }

    protected virtual void GenerateImage() {
      if (InvokeRequired) {
        Invoke((Action)GenerateImage);
        return;
      }
      if (!Visible) {
        RenderingRequired = true;
      } else {
        if ((pictureBox.Width == 0) || (pictureBox.Height == 0)) {
          pictureBox.Image = pictureBox.ErrorImage;
          if (Picture != null) Picture.Dispose();
          Picture = null;
        } else {
          if (Picture != null) Picture.Dispose();
          Picture = new Bitmap(pictureBox.Width, pictureBox.Height);
          using (var graphics = Graphics.FromImage(Picture)) {
            graphics.SmoothingMode = SmoothingMode;
            graphics.SetClip(new System.Drawing.Rectangle(0, 0, pictureBox.Width, pictureBox.Height));
            Chart.Render(graphics, pictureBox.Width, pictureBox.Height);
          }
        }
        pictureBox.Image = Picture;
        RenderingRequired = false;
      }
    }

    public event EventHandler ModeChanged;
    protected void OnModeChanged() {
      var handler = ModeChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }

    private void ChartControl_Load(object sender, EventArgs e) {
      if (!SuppressRender) GenerateImage();
    }

    #region Helpers
    private RadioButton CreateChartModeRadioButton(ChartMode chartMode) {
      var rb = new RadioButton {
        Appearance = Appearance.Button,
        Image = chartMode.Image,
        Size = new Size(24, 24),
        TabStop = true,
        Tag = chartMode,
        UseVisualStyleBackColor = true
      };

      rb.CheckedChanged += (sender, args) => { if (rb.Checked) chartMode.Select(); };

      return rb;
    }

    private ToolStripMenuItem CreateChartModeMenuItem(ChartMode chartMode) {
      var mi = new ToolStripMenuItem(chartMode.Text) {
        CheckOnClick = true,
        Image = chartMode.Image,
        Tag = chartMode
      };

      mi.CheckedChanged += (sender, args) => { if (mi.Checked) chartMode.Select(); };

      return mi;
    }
    #endregion
  }
}