/*
    * Copyright 2002 - 2007 JEuclid, http://jeuclid.sf.net
    * 
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *      http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /* $Id: MathImpl.java,v c169040ef426 2009/10/28 08:55:31 max $ */
  
  package net.sourceforge.jeuclid.elements.generic;
  
  import net.sourceforge.jeuclid.Constants;
  import net.sourceforge.jeuclid.LayoutContext;
  import net.sourceforge.jeuclid.context.Display;
  import net.sourceforge.jeuclid.context.Parameter;
  import net.sourceforge.jeuclid.elements.presentation.AbstractContainer;
  
  import org.apache.batik.dom.AbstractDocument;
  import org.w3c.dom.Node;
  import org.w3c.dom.mathml.MathMLMathElement;
  
  /**
   * The root element for creating a MathElement tree.
   * 
   * @version $Revision: c169040ef426 $
   */
  public final class MathImpl extends AbstractContainer implements
          MathMLMathElement {
  
      private final class ChildContext implements LayoutContext {
          private final LayoutContext context;
  
          private ChildContext(final LayoutContext myContext) {
              this.context = myContext;
          }
  
          public Object getParameter(final Parameter which) {
              Object retVal;
              if (Parameter.DISPLAY.equals(which)) {
                  if (MathImpl.DISPLAY_BLOCK.equals(MathImpl.this.getDisplay())) {
                      retVal = Display.BLOCK;
                  } else {
                      retVal = Display.INLINE;
                  }
              } else {
                  retVal = MathImpl.this.applyLocalAttributesToContext(
                          this.context).getParameter(which);
              }
              retVal = this.getParamValueFromJEuclidExt(which, retVal);
              return retVal;
          }
  
          private Object getParamValueFromJEuclidExt(final Parameter which,
                  final Object currentValue) {
              Object retVal = currentValue;
              final String s0 = MathImpl.this.getAttributeNS(
                      Constants.NS_JEUCLID_EXT, which.getOptionName());
              if ((s0 != null) && (s0.length() > 0)) {
                  retVal = which.fromString(s0);
              } else {
                  retVal = this.getDeprecatedParamValuesFromJEuclidExt(which,
                          retVal);
              }
              return retVal;
          }
  
          private Object getDeprecatedParamValuesFromJEuclidExt(
                  final Parameter which, final Object currentValue) {
              // old namespace
              Object retVal = currentValue;
              final String s = MathImpl.this.getAttributeNS(
                      Constants.NS_OLD_JEUCLID_EXT, which.getOptionName());
              if ((s != null) && (s.length() > 0)) {
                  retVal = which.fromString(s);
              } else {
                  // Support deprecated attributes
                  final String s2 = MathImpl.this.getAttributeNS(
                          Constants.NS_OLD_JEUCLID_EXT, which.toString());
                  if ((s2 != null) && (s2.length() > 0)) {
                      retVal = which.fromString(s2);
                  }
              }
              return retVal;
          }
      }
  
      /** attribute for display. */
      public static final String ATTR_DISPLAY = "display";
  
      /** attribute for macros. */
     public static final String ATTR_MACROS = "macros";
 
     /**
      * The XML element from this class.
      */
     public static final String ELEMENT = "math";
 
     private static final long serialVersionUID = 1L;
 
     /** attribute for mode. */
     private static final String ATTR_MODE = "mode";
 
     private static final String DISPLAY_INLINE = "inline";
 
     private static final String DISPLAY_BLOCK = "block";
 
     // Happens to be display as well.
     private static final String DEPRECATED_BLOCK_VALUE_FOR_MODE = MathImpl.ATTR_DISPLAY;
 
     /**
      * Default constructor. Sets MathML Namespace.
      * 
      * @param qname
      *            Qualified name.
      * @param odoc
      *            Owner Document.
      */
     public MathImpl(final String qname, final AbstractDocument odoc) {
         super(qname, odoc);
     }
 
     /** {@inheritDoc} */
     @Override
     protected Node newNode() {
         return new MathImpl(this.nodeName, this.ownerDocument);
     }
 
     /**
      * Set the type of equation.
      * 
      * @param display
      *            INLINE|BLOCK
      */
     public void setDisplay(final String display) {
         this.setAttribute(MathImpl.ATTR_DISPLAY, display);
     }
 
     /**
      * Returns the display.
      * 
      * @return Display display
      */
     public String getDisplay() {
         final String retVal;
         final String attrDisplay = this.getMathAttribute(MathImpl.ATTR_DISPLAY);
         if (attrDisplay == null) {
             if (MathImpl.DEPRECATED_BLOCK_VALUE_FOR_MODE.equalsIgnoreCase(this
                     .getMathAttribute(MathImpl.ATTR_MODE))) {
                 retVal = MathImpl.DISPLAY_BLOCK;
             } else {
                 retVal = MathImpl.DISPLAY_INLINE;
             }
         } else {
             if (MathImpl.DISPLAY_BLOCK.equalsIgnoreCase(attrDisplay)) {
                 retVal = MathImpl.DISPLAY_BLOCK;
             } else {
                 retVal = MathImpl.DISPLAY_INLINE;
             }
         }
         return retVal;
     }
 
     /** {@inheritDoc} */
     @Override
     public LayoutContext getChildLayoutContext(final int childNum,
             final LayoutContext context) {
         return new ChildContext(context);
     }
 
     /** {@inheritDoc} */
     public String getMacros() {
         return this.getMathAttribute(MathImpl.ATTR_MACROS);
     }
 
     /** {@inheritDoc} */
     public void setMacros(final String macros) {
         this.setAttribute(MathImpl.ATTR_MACROS, macros);
     }
 
 }