source: branches/HeuristicLab.Problems.GrammaticalOptimization/SharpVectorCss/Css/CssPrimitiveLengthValue.cs @ 14035

using System;
using System.Xml;
using System.Text.RegularExpressions;

namespace SharpVectors.Dom.Css
{
  public class CssPrimitiveLengthValue : CssPrimitiveValue
  {
    //protected const double Dpi = 96;
        protected const double Dpi = 90; // The common default value for this is 90, not 96
    protected const double CmPerIn = 2.54;

    #region Constructors
    public CssPrimitiveLengthValue(string number, string unit, bool readOnly) : base(number+unit, readOnly)
    {
      _setType(unit);
      SetFloatValue(number);
    }

    public CssPrimitiveLengthValue(string cssText, bool readOnly) : base(cssText, readOnly)
    {
      OnSetCssText(cssText);
    }

    public CssPrimitiveLengthValue(double number, string unit, bool readOnly) : base(number+unit, readOnly)
    {
      _setType(unit);
      SetFloatValue(number);
    }

    protected CssPrimitiveLengthValue() : base()
    {
    }
    #endregion

    public override CssValue GetAbsoluteValue(string propertyName, XmlElement elm)
    {
      return new CssAbsPrimitiveLengthValue(this, propertyName, elm);
    }

    protected override void OnSetCssText(string cssText)
    {
      Regex re = new Regex(CssValue.LengthPattern);
      Match match = re.Match(cssText);
      if(match.Success)
      {
        _setType(match.Groups["lengthUnit"].Value);
        SetFloatValue(match.Groups["lengthNumber"].Value);
      }
      else
      {
        throw new DomException(DomExceptionType.SyntaxErr, "Unrecognized length format: " + cssText);
      }
    }
    private void _setType(string unit)
    {
      switch(unit)
      {
        case "cm":
          SetPrimitiveType(CssPrimitiveType.Cm);
          break;
        case "mm":
          SetPrimitiveType(CssPrimitiveType.Mm);
          break;
        case "px":
          SetPrimitiveType(CssPrimitiveType.Px);
          break;
        case "em":
          SetPrimitiveType(CssPrimitiveType.Ems);
          break;
        case "ex":
          SetPrimitiveType(CssPrimitiveType.Exs);
          break;
        case "pc":
          SetPrimitiveType(CssPrimitiveType.Pc);
          break;
        case "pt":
          SetPrimitiveType(CssPrimitiveType.Pt);
          break;
        case "in":
          SetPrimitiveType(CssPrimitiveType.In);
          break;
        case "%":
          SetPrimitiveType(CssPrimitiveType.Percentage);
          break;
        case "":
          SetPrimitiveType(CssPrimitiveType.Number);
          break;
        default:
          throw new DomException(DomExceptionType.SyntaxErr, "Unknown length unit");
      }
    }

    // only for absolute values
    private double _getPxLength()
    {
      switch(PrimitiveType)
      {
        case CssPrimitiveType.In:
          return floatValue * Dpi;
        case CssPrimitiveType.Cm:
          return floatValue / CmPerIn * Dpi;
        case CssPrimitiveType.Mm:
          return floatValue / 10 / CmPerIn * Dpi;
        case CssPrimitiveType.Pt:
          return floatValue / 72 * Dpi;
        case CssPrimitiveType.Pc:
          return floatValue / 6 * Dpi;
        default:
          return floatValue;
      }
    }

    private double _getInLength()
    {
      return _getPxLength() / Dpi;
    }

    public override double GetFloatValue(CssPrimitiveType unitType)
    {
      double ret = Double.NaN;
      switch(PrimitiveType)
      {
        case CssPrimitiveType.Number:
        case CssPrimitiveType.Px:
        case CssPrimitiveType.Cm:
        case CssPrimitiveType.Mm:
        case CssPrimitiveType.In:
        case CssPrimitiveType.Pt:
        case CssPrimitiveType.Pc:
          if(unitType == CssPrimitiveType.Px) ret = _getPxLength();
          else if(unitType == CssPrimitiveType.Number) ret = _getPxLength();
          else if(unitType == CssPrimitiveType.In) ret = _getInLength();
          else if(unitType == CssPrimitiveType.Cm) ret = _getInLength() * CmPerIn;
          else if(unitType == CssPrimitiveType.Mm) ret = _getInLength() * CmPerIn * 10;
          else if(unitType == CssPrimitiveType.Pt) ret = _getInLength() * 72;
          else if(unitType == CssPrimitiveType.Pc) ret = _getInLength() * 6;
          break;
        case CssPrimitiveType.Percentage:
          if(unitType == CssPrimitiveType.Percentage) ret = floatValue;
          break;
        case CssPrimitiveType.Ems:
          if(unitType == CssPrimitiveType.Ems) ret = floatValue;
          break;
        case CssPrimitiveType.Exs:
          if(unitType == CssPrimitiveType.Exs) ret = floatValue;
          break;
      }
      if(Double.IsNaN(ret))
      {
        throw new DomException(DomExceptionType.InvalidAccessErr);
      }
      else
      {
        return ret;
      }
    }

    public override string CssText
    {
      get
      {
        return GetFloatValue(PrimitiveType).ToString(CssNumber.Format) + PrimitiveTypeAsString;
      }
    }
  }
}