using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Drawing.Drawing2D;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Windows.Forms;
using HeuristicLab.Core.Views;
using HeuristicLab.MainForm;

namespace HeuristicLab.Analysis.FitnessLandscape.BoxChart {

  [View("ColorValue View")]
  [Content(typeof(ColorValue), IsDefaultView = true)]
  public sealed partial class ColorValueView : NamedItemView {

    private Bitmap colorWheel;
    private const int RADIUS = 128;
    private const int COLOR_COUNT = 128;

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

    public ColorValueView() {
      InitializeComponent();
      InitializeColorWheel();
    }

    protected override void DeregisterContentEvents() {
      Content.ColorChanged -= Content_ColorChanged;
      base.DeregisterContentEvents();
    }


    protected override void RegisterContentEvents() {
      base.RegisterContentEvents();
      Content.ColorChanged += Content_ColorChanged;
    }

    #region Event Handlers (Content)
    private void Content_ColorChanged(object sender, EventArgs e) {
      if (InvokeRequired) {
        Invoke(new EventHandler(Content_ColorChanged), sender, e);
      } else {
        UpdateControls();
        colorWheelPanel.Invalidate();
        colorPanel.Invalidate();
        brightnessPanel.Invalidate();
      }
    }
    #endregion

    protected override void OnContentChanged() {
      base.OnContentChanged();
      Update(() => {
        UpdateControls();
        colorWheelPanel.Invalidate();
        colorPanel.Invalidate();
        brightnessPanel.Invalidate();
      });
    }

    private void UpdateControls() {
      if (Content == null) {
        hueScrollBar.Value = 0;
        saturationScrollBar.Value = 0;
        brightnessScrollBar.Value = 0;
        hueUpDown.Value = 0;
        saturationUpDown.Value = 0;
        brightnessUpDown.Value = 0;
        redScrollBar.Value = 0;
        greenScrollBar.Value = 0;
        blueScrollBar.Value = 0;
        redUpDown.Value = 0;
        greenUpDown.Value = 0;
        blueUpDown.Value = 0;
      }
      else {
        hueScrollBar.Value = (int)Math.Round(Content.H);
        saturationScrollBar.Value = (int)Math.Round(Content.S*100);
        brightnessScrollBar.Value = (int)Math.Round(Content.V*100);
        hueUpDown.Value = (decimal)Math.Round(Content.H);
        saturationUpDown.Value = (decimal)Math.Round(Content.S*100);
        brightnessUpDown.Value = (decimal)Math.Round(Content.V*100);
        redScrollBar.Value = Content.R;
        greenScrollBar.Value = Content.G;
        blueScrollBar.Value = Content.B;
        redUpDown.Value = Content.R;
        greenUpDown.Value = Content.G;
        blueUpDown.Value = Content.B;
      }
    }

    protected override void SetEnabledStateOfControls() {
      base.SetEnabledStateOfControls();
      hueScrollBar.Enabled =
        saturationScrollBar.Enabled = 
        brightnessScrollBar.Enabled =
        redScrollBar.Enabled =
        greenScrollBar.Enabled = 
        blueScrollBar.Enabled =
        hueUpDown.Enabled = 
        saturationUpDown.Enabled =
        brightnessUpDown.Enabled =
        redUpDown.Enabled =
        greenUpDown.Enabled =
        blueUpDown.Enabled =
          Content != null;
    }

    private static Color GetFullColor(ColorValue c) {
      return new ColorValue(c.H, c.S, 1).Color;
    }

    private static Point GetColorPoint(ColorValue c, int size) {
      return GetPoint(c.H, c.S*size/2, new Point(size/2, size/2));
    }

    #region Event Handlers (child controls)
    private void colorWheelPanel_Paint(object sender, PaintEventArgs e) {
      e.Graphics.DrawImage(colorWheel, 0, 0, colorWheelPanel.Width, colorWheelPanel.Height);
      if (Content != null)
        DrawColorPointer(e.Graphics,
          GetColorPoint(Content, Math.Min(colorWheelPanel.Width, colorWheelPanel.Height)));
    }

    private void brightnessPanel_Paint(object sender, PaintEventArgs e) {
      if (Content != null) {
        var bar = brightnessPanel.ClientRectangle;
        bar.Width -= 10;
        using (var lgb = new LinearGradientBrush(bar, GetFullColor(Content), Color.Black, LinearGradientMode.Vertical)) {
          e.Graphics.FillRectangle(lgb, bar);
        }
        DrawBrighnessPointer(e.Graphics, new Point(bar.Width-9, (int)Math.Round((1.0-Content.V)*bar.Height)));
      }
    }

    private void colorPanel_Paint(object sender, PaintEventArgs e) {
      if (Content != null) {
        using (var b = new SolidBrush(Content.Color)) {
          e.Graphics.FillRectangle(b, 0, 0, colorPanel.Width, colorPanel.Height);
        }
      }
    }

    private bool updateInProgress = false;
    private void Update(Action thunk) {
      if (!updateInProgress) {
        updateInProgress = true;
        thunk();
        updateInProgress = false;
      }
    }

    private void hueScrollBar_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.H = hueScrollBar.Value);
    }

    private void saturationScrollBar_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.S = saturationScrollBar.Value/100.0);
    }

    private void brightnessScrollBar_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.V = brightnessScrollBar.Value/100.0);
    }

    private void redScrollBar_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.R = redScrollBar.Value);
    }

    private void greenScrollBar_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.G = greenScrollBar.Value);
    }

    private void blueScrollBar_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.B = blueScrollBar.Value);
    }

    private void hueUpDown_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.H = (double)hueUpDown.Value);
    }

    private void saturationUpDown_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.S = (double)saturationUpDown.Value/100.0);
    }

    private void brightnessUpDown_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.V = (double)brightnessUpDown.Value/100.0);
    }

    private void redUpDown_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.R = (int)redUpDown.Value);
    }

    private void greenUpDown_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.G = (int)greenUpDown.Value);
    }

    private void blueUpDown_ValueChanged(object sender, EventArgs e) {
      Update(() => Content.B = (int)blueUpDown.Value);
    }

    private void colorWheelPanel_MouseDown(object sender, MouseEventArgs e) {
      Update(() => SetColorWheel(e.Location));
    }

    private void colorWheelPanel_MouseMove(object sender, MouseEventArgs e) {
      if (e.Button == MouseButtons.Left)
        Update(() => SetColorWheel(e.Location));
    }

    private void brightnessPanel_MouseDown(object sender, MouseEventArgs e) {
      Update(() => SetBrightness(e.Location));
    }

    private void brightnessPanel_MouseMove(object sender, MouseEventArgs e) {
      if (e.Button == MouseButtons.Left) {
        Update(() => SetBrightness(e.Location));
      }
    }

    private void colorPanel_DoubleClick(object sender, EventArgs e) {
      colorDialog.Color = Content.Color;
      if (colorDialog.ShowDialog() == DialogResult.OK) {
        Update(() => Content.Color = colorDialog.Color);
      }
    }
    private void defaultColorPanel_MouseClick(object sender, MouseEventArgs e) {
      if (Content != null)
        Update(() => Content.Color = ((Panel)sender).BackColor);
    }
    #endregion

    #region Auxiliary Functions
    private void DrawColorPointer(Graphics g, Point p) {
      g.DrawRectangle(Pens.Black, p.X - 3, p.Y - 3, 6, 6);
    }

    private void DrawBrighnessPointer(Graphics g, Point p) {
      g.FillPolygon(Brushes.Black, new[] {
        p,
        new Point(p.X + 10, p.Y + 5), 
        new Point(p.X + 10, p.Y - 5)});
    }

    private void InitializeColorWheel() {
      colorWheel = new Bitmap(256, 256);
      using (var brush = new PathGradientBrush(GetPoints(RADIUS, new Point(RADIUS, RADIUS))) {
        CenterColor = Color.White,
        CenterPoint = new PointF(RADIUS, RADIUS),
        SurroundColors = GetColors()
      }) {
        using (var g = Graphics.FromImage(colorWheel)) {
          g.FillEllipse(brush, 0, 0, colorWheelPanel.Width, colorWheel.Height);
        }
      }
      SetStyle(ControlStyles.AllPaintingInWmPaint, true);
      SetStyle(ControlStyles.UserPaint, true);
      SetStyle(ControlStyles.DoubleBuffer, true);
    }

    private static Point[] GetPoints(double radius, Point center) {
      var points = new Point[COLOR_COUNT];
      for (int i = 0; i<COLOR_COUNT; i++) {
        points[i] = GetPoint(i*360.0/COLOR_COUNT, radius, center);
      }
      return points;
    }

    private static Point GetPoint(double degrees, double radius, Point center) {
      var rad = degrees*Math.PI/180;
      return new Point(
        (int)Math.Round(center.X + radius * Math.Cos(rad)),
        (int)Math.Round(center.Y + radius * Math.Sin(rad)));
    }

    private Color[] GetColors() {
      var colors = new Color[COLOR_COUNT];
      for (int i = 0; i<COLOR_COUNT; i++) {
        colors[i] = new ColorValue(i*360.0/COLOR_COUNT, 1d, 1d).Color;
      }
      return colors;
    }

    private void SetColorWheel(Point p) {
      if (Content == null) return;
      var x = p.X - colorWheelPanel.Width/2f;
      var y = p.Y - colorWheelPanel.Height/2f;
      Content.S = Math.Min(1, Math.Max(0, Math.Sqrt(sqr(x) + sqr(y))/(colorWheelPanel.Width/2f)));
      var angle = Math.Atan2(y, x)*180/Math.PI;
      if (angle < 0) angle += 360;
      Content.H = Math.Min(360, Math.Max(0, angle));
    }

    private void SetBrightness(Point p) {
      if (Content != null)
        Content.V = Math.Max(0, Math.Min(1, 1 - 1.0*p.Y/brightnessPanel.Height));
    }

    private static double sqr(double x) { return x*x; }
    #endregion



  }
}