#region PDFsharp Charting - A .NET charting library based on PDFsharp
//
// Authors:
//   Niklas Schneider (mailto:Niklas.Schneider@pdfsharp.com)
//
// Copyright (c) 2005-2008 empira Software GmbH, Cologne (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using PdfSharp.Drawing;

namespace PdfSharp.Charting.Renderers
{
  /// <summary>
  /// Represents a exploded pie plot area renderer.
  /// </summary>
  internal class PieExplodedPlotAreaRenderer : PiePlotAreaRenderer
  {
    /// <summary>
    /// Initializes a new instance of the PieExplodedPlotAreaRenderer class
    /// with the specified renderer parameters.
    /// </summary>
    internal PieExplodedPlotAreaRenderer(RendererParameters parms)
      : base(parms)
    { }

    /// <summary>
    /// Calculate angles for each sector.
    /// </summary>
    protected override void CalcSectors()
    {
      ChartRendererInfo cri = (ChartRendererInfo)this.rendererParms.RendererInfo;
      if (cri.seriesRendererInfos.Length == 0)
        return;

      SeriesRendererInfo sri = cri.seriesRendererInfos[0];

      double sumValues = sri.SumOfPoints;
      if (sumValues == 0)
        return;

      double textMeasure = 0;
      if (sri.dataLabelRendererInfo != null && sri.dataLabelRendererInfo.Position == DataLabelPosition.OutsideEnd)
      {
        foreach (DataLabelEntryRendererInfo dleri in sri.dataLabelRendererInfo.Entries)
        {
          textMeasure = Math.Max(textMeasure, dleri.Width);
          textMeasure = Math.Max(textMeasure, dleri.Height);
        }
      }

      XRect pieRect = cri.plotAreaRendererInfo.Rect;
      if (textMeasure != 0)
      {
        pieRect.X += textMeasure;
        pieRect.Y += textMeasure;
        pieRect.Width -= 2 * textMeasure;
        pieRect.Height -= 2 * textMeasure;
      }

      XPoint origin = new XPoint(pieRect.X + pieRect.Width / 2, pieRect.Y + pieRect.Height / 2);
      XRect innerRect = new XRect();
      XPoint p1 = new XPoint();

      double midAngle = 0, sectorStartAngle = 0, sectorSweepAngle = 0,
             deltaAngle = 2, startAngle = 270, sweepAngle = 0,
             rInnerCircle = pieRect.Width / 15,
             rOuterCircle = pieRect.Width / 2;

      foreach (SectorRendererInfo sector in sri.pointRendererInfos)
      {
        if (!double.IsNaN(sector.point.value) && sector.point.value != 0)
        {
          sweepAngle = 360 / (sumValues / Math.Abs(sector.point.value));

          midAngle = startAngle + sweepAngle / 2;
          sectorStartAngle = Math.Max(0, startAngle + deltaAngle);
          sectorSweepAngle = Math.Max(sweepAngle, sweepAngle - deltaAngle);

          p1.X = origin.X + rInnerCircle * Math.Cos(midAngle / 180 * Math.PI);
          p1.Y = origin.Y + rInnerCircle * Math.Sin(midAngle / 180 * Math.PI);
          innerRect.X = p1.X - rOuterCircle + rInnerCircle;
          innerRect.Y = p1.Y - rOuterCircle + rInnerCircle;
          innerRect.Width = (rOuterCircle - rInnerCircle) * 2;
          innerRect.Height = innerRect.Width;

          sector.Rect = innerRect;
          sector.StartAngle = sectorStartAngle;
          sector.SweepAngle = sectorSweepAngle;

          startAngle += sweepAngle;
        }
        else
        {
          sector.StartAngle = double.NaN;
          sector.SweepAngle = double.NaN;
        }
      }
    }
  }
}
