/*
    * Copyright 2002,2004 The Apache Software Foundation.
    *
    * 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.
   */
  package org.apache.commons.jelly.tags.swing;
  
  import java.awt.Component;
  import java.awt.GridBagConstraints;
  
  import org.apache.commons.jelly.JellyTagException;
  import org.apache.commons.jelly.TagSupport;
  import org.apache.commons.jelly.XMLOutput;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  /***
   * Represents a tabular cell inside a <tl> tag inside a <tableLayout>
   * tag which mimicks the <td> HTML tag.
   *
   * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
   * @version $Revision: 155420 $
   */
  public class TdTag extends TagSupport implements ContainerTag {
  
      /*** The Log to which logging calls will be made. */
      private static final Log log = LogFactory.getLog(TdTag.class);
  
      private String align;
      private String valign;
      private int colspan = 1;
      private int rowspan = 1;
      private boolean colfill = false;
      private boolean rowfill = false;
  
      public TdTag() {
      }
  
      // ContainerTag interface
      //-------------------------------------------------------------------------
  
      /***
       * Adds a child component to this parent
       */
      public void addChild(Component component, Object constraints) throws JellyTagException {
          // add my child component to the layout manager
          TrTag tag = (TrTag) findAncestorWithClass( TrTag.class );
          if (tag == null) {
              throw new JellyTagException( "this tag must be nested within a <tr> tag" );
          }
          tag.addCell(component, createConstraints());
      }
  
  
      // Tag interface
      //-------------------------------------------------------------------------
      public void doTag(final XMLOutput output) throws JellyTagException {
          invokeBody(output);
      }
  
  
      // Properties
      //-------------------------------------------------------------------------
  
      /***
       * Sets the horizontal alignment to a case insensitive value of {LEFT, CENTER, RIGHT}
       */
      public void setAlign(String align) {
          this.align = align;
      }
  
      /***
       * Sets the vertical alignment to a case insensitive value of {TOP, MIDDLE, BOTTOM}
       */
      public void setValign(String valign) {
          this.valign = valign;
      }
  
  
      /***
       * Sets the number of columns that this cell should span. The default value is 1
       */
      public void setColspan(int colspan) {
          this.colspan = colspan;
      }
  
      /***
       * Sets the number of rows that this cell should span. The default value is 1
       */
     public void setRowspan(int rowspan) {
         this.rowspan = rowspan;
     }
 
     /***
      * Returns the colfill.
      * @return boolean
      */
     public boolean isColfill() {
         return colfill;
     }
 
     /***
      * Returns the rowfill.
      * @return boolean
      */
     public boolean isRowfill() {
         return rowfill;
     }
 
     /***
      * Sets whether or not this column should allow its component to stretch to fill the space available
      */
     public void setColfill(boolean colfill) {
         this.colfill = colfill;
     }
 
     /***
      * Sets whether or not this row should allow its component to stretch to fill the space available
      */
     public void setRowfill(boolean rowfill) {
         this.rowfill = rowfill;
     }
 
 
     // Implementation methods
     //-------------------------------------------------------------------------
 
     /***
      * Factory method to create a new constraints object
      */
     protected GridBagConstraints createConstraints() {
         GridBagConstraints answer = new GridBagConstraints();
         answer.anchor = getAnchor();
         if (colspan < 1) {
             colspan = 1;
         }
         if (rowspan < 1) {
             rowspan = 1;
         }
         if (isColfill())  {
             answer.fill = isRowfill()
                 ? GridBagConstraints.BOTH
                 : GridBagConstraints.HORIZONTAL;
         }
         else {
             answer.fill = isRowfill()
                 ? GridBagConstraints.VERTICAL
                 : GridBagConstraints.NONE;
         }
         answer.weightx = 0.2;
         answer.weighty = 0;
         answer.gridwidth = colspan;
         answer.gridheight = rowspan;
         return answer;
     }
 
     /***
      * @return the GridBagConstraints enumeration for achor
      */
     protected int getAnchor() {
         boolean isTop = "top".equalsIgnoreCase(valign);
         boolean isBottom = "bottom".equalsIgnoreCase(valign);
 
         if ("center".equalsIgnoreCase(align)) {
             if (isTop) {
                 return GridBagConstraints.NORTH;
             }
             else if (isBottom) {
                 return GridBagConstraints.SOUTH;
             }
             else {
                 return GridBagConstraints.CENTER;
             }
         }
         else if ("right".equalsIgnoreCase(align)) {
             if (isTop) {
                 return GridBagConstraints.NORTHEAST;
             }
             else if (isBottom) {
                 return GridBagConstraints.SOUTHEAST;
             }
             else {
                 return GridBagConstraints.EAST;
             }
         }
         else {
             // defaults to left
             if (isTop) {
                 return GridBagConstraints.NORTHWEST;
             }
             else if (isBottom) {
                 return GridBagConstraints.SOUTHWEST;
             }
             else {
                 return GridBagConstraints.WEST;
             }
         }
     }
 }