/*!
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program 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 Lesser General Public License for more details.
*
* Copyright (c) 2002-2013 Pentaho Corporation.. All rights reserved.
*/
package org.pentaho.reporting.libraries.css.resolver.function.values;
import org.pentaho.reporting.libraries.css.util.ColorUtil;
import org.pentaho.reporting.libraries.css.values.CSSColorValue;
import org.pentaho.reporting.libraries.css.values.CSSFunctionValue;
import org.pentaho.reporting.libraries.css.values.CSSValue;
import org.pentaho.reporting.libraries.css.values.CSSNumericType;
import org.pentaho.reporting.libraries.css.values.CSSNumericValue;
import org.pentaho.reporting.libraries.css.values.CSSStringValue;
import org.pentaho.reporting.libraries.css.dom.LayoutElement;
import org.pentaho.reporting.libraries.css.dom.DocumentContext;
import org.pentaho.reporting.libraries.css.resolver.function.FunctionUtilities;
import org.pentaho.reporting.libraries.css.resolver.function.StyleValueFunction;
import org.pentaho.reporting.libraries.css.resolver.FunctionEvaluationException;
public class HslValueFunction implements StyleValueFunction
{
public HslValueFunction()
{
}
protected int validateHueParameter (final CSSValue value) throws FunctionEvaluationException
{
final CSSNumericValue nval;
if (value instanceof CSSStringValue)
{
// I shouldn't do this, but ..
final CSSStringValue strVal = (CSSStringValue) value;
nval = FunctionUtilities.parseNumberValue(strVal.getValue());
}
else if (value instanceof CSSNumericValue == false)
{
throw new FunctionEvaluationException("Expected a number");
}
else
{
nval = (CSSNumericValue) value;
}
if (nval.getType().equals(CSSNumericType.NUMBER))
{
return (int) (nval.getValue() % 360);
}
throw new FunctionEvaluationException("Expected a number, not a length");
}
protected float validateOtherParameter (final CSSValue value) throws FunctionEvaluationException
{
final CSSNumericValue nval;
if (value instanceof CSSStringValue)
{
// I shouldn't do this, but ..
final CSSStringValue strVal = (CSSStringValue) value;
nval = FunctionUtilities.parseNumberValue(strVal.getValue());
}
else if (value instanceof CSSNumericValue == false)
{
throw new FunctionEvaluationException("Expected a number");
}
else
{
nval = (CSSNumericValue) value;
}
if (nval.getType().equals(CSSNumericType.PERCENTAGE))
{
return (float) (nval.getValue() % 100);
}
throw new FunctionEvaluationException("Expected a number, not a length");
}
public boolean isAutoResolveable()
{
return true;
}
public CSSValue evaluate(final DocumentContext layoutProcess,
final LayoutElement element,
final CSSFunctionValue function)
throws FunctionEvaluationException
{
final CSSValue[] values = function.getParameters();
if (values.length == 3)
{
final int hueValue = validateHueParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[0]));
final float saturationValue = validateOtherParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[1]));
final float lightValue = validateOtherParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[2]));
final float[] rgb = ColorUtil.hslToRGB
(hueValue, saturationValue, lightValue);
return new CSSColorValue(rgb[0], rgb[1], rgb[2]);
}
else if (values.length == 4)
{
final int hueValue = validateHueParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[0]));
final float saturationValue = validateOtherParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[1]));
final float lightValue = validateOtherParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[2]));
final float alphaValue = validateOtherParameter
(FunctionUtilities.resolveParameter(layoutProcess, element, values[3]));
final float[] rgb =
ColorUtil.hslToRGB(hueValue, saturationValue, lightValue);
return new CSSColorValue(rgb[0], rgb[1], rgb[2], alphaValue);
}
else
{
throw new FunctionEvaluationException("Expected either three or four parameters.");
}
}
}