#region PDFsharp Charting - A .NET charting library based on PDFsharp
//
// Authors:
//   Niklas Schneider (mailto:Niklas.Schneider@pdfsharp.com)
//
// Copyright (c) 2005-2007 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 System.Diagnostics;
using PdfSharp.Drawing;

namespace PdfSharp.Charting.Renderers
{
  /// <summary>
  /// Represents a plot area renderer for bars.
  /// </summary>
  internal abstract class BarPlotAreaRenderer : PlotAreaRenderer
  {
    /// <summary>
    /// Initializes a new instance of the BarPlotAreaRenderer class with the
    /// specified renderer parameters.
    /// </summary>
    internal BarPlotAreaRenderer(RendererParameters parms) : base(parms)
    {
    }

    /// <summary>
    /// Layouts and calculates the space for each bar.
    /// </summary>
    internal override void Format()
    {
      ChartRendererInfo cri = (ChartRendererInfo)this.rendererParms.RendererInfo;

      double xMin = cri.xAxisRendererInfo.MinimumScale;
      double xMax = cri.xAxisRendererInfo.MaximumScale;
      double yMin = cri.yAxisRendererInfo.MinimumScale;
      double yMax = cri.yAxisRendererInfo.MaximumScale;
      double xMajorTick = cri.xAxisRendererInfo.MajorTick;

      XRect plotAreaBox = cri.plotAreaRendererInfo.Rect;

      cri.plotAreaRendererInfo.matrix = XMatrix.Identity;
      cri.plotAreaRendererInfo.matrix.Translate(-yMin, xMin);
      cri.plotAreaRendererInfo.matrix.Scale(plotAreaBox.Width / (yMax - yMin), plotAreaBox.Height / (xMax - xMin), XMatrixOrder.Append);
      cri.plotAreaRendererInfo.matrix.Translate(plotAreaBox.X, plotAreaBox.Y, XMatrixOrder.Append);

      CalcBars();
    }

    /// <summary>
    /// Draws the content of the bar plot area.
    /// </summary>
    internal override void Draw()
    {
      ChartRendererInfo cri = (ChartRendererInfo)this.rendererParms.RendererInfo;

      XRect plotAreaBox = cri.plotAreaRendererInfo.Rect;
      if (plotAreaBox.IsEmpty)
        return;

      XGraphics gfx = this.rendererParms.Graphics;

      double xMin = cri.xAxisRendererInfo.MinimumScale;
      double xMax = cri.xAxisRendererInfo.MaximumScale;
      double yMin = cri.yAxisRendererInfo.MinimumScale;
      double yMax = cri.yAxisRendererInfo.MaximumScale;
      double xMajorTick = cri.xAxisRendererInfo.MajorTick;

      LineFormatRenderer lineFormatRenderer;

      // Under some circumstances it is possible that no zero base line will be drawn,
      // e. g. because of unfavourable minimum/maximum scale and/or major tick, so force to draw
      // a zero base line if necessary.
      if (cri.yAxisRendererInfo.MajorGridlinesLineFormat != null ||
          cri.yAxisRendererInfo.MinorGridlinesLineFormat != null)
      {
        if (yMin < 0 && yMax > 0)
        {
          XPoint[] points = new XPoint[2];
          points[0].X = 0;
          points[0].Y = xMin;
          points[1].X = 0;
          points[1].Y = xMax;
          cri.plotAreaRendererInfo.matrix.TransformPoints(points);

          if (cri.yAxisRendererInfo.MinorGridlinesLineFormat != null)
            lineFormatRenderer = new LineFormatRenderer(gfx, cri.yAxisRendererInfo.MinorGridlinesLineFormat);
          else
            lineFormatRenderer = new LineFormatRenderer(gfx, cri.yAxisRendererInfo.MajorGridlinesLineFormat);

          lineFormatRenderer.DrawLine(points[0], points[1]);
        }
      }

      // Draw bars
      XGraphicsState state = gfx.Save();
      foreach (SeriesRendererInfo sri in cri.seriesRendererInfos)
      {
        foreach (ColumnRendererInfo column in sri.pointRendererInfos)
        {
          // Do not draw bar if value is outside yMin/yMax range. Clipping does not make sense.
          if (IsDataInside(yMin, yMax, column.point.value))
            gfx.DrawRectangle(column.FillFormat, column.Rect);
        }
      }

      // Draw borders around bar.
      // A border can overlap neighbor bars, so it is important to draw borders at the end.
      foreach (SeriesRendererInfo sri in cri.seriesRendererInfos)
      {
        foreach (ColumnRendererInfo column in sri.pointRendererInfos)
        {
          // Do not draw bar if value is outside yMin/yMax range. Clipping does not make sense.
          if (IsDataInside(yMin, yMax, column.point.value))
          {
            lineFormatRenderer = new LineFormatRenderer(gfx, column.LineFormat);
            lineFormatRenderer.DrawRectangle(column.Rect);
          }
        }
      }
      gfx.Restore(state);
    }

    /// <summary>
    /// Calculates the position, width and height of each bar of all series.
    /// </summary>
    protected abstract void CalcBars();

    /// <summary>
    /// If yValue is within the range from yMin to yMax returns true, otherwise false.
    /// </summary>
    protected abstract bool IsDataInside(double yMin, double yMax, double yValue);
  }
}
