source: trunk/src/org/expeditee/core/Anchoring.java@ 1097

package org.expeditee.core;

import org.expeditee.core.bounds.AxisAlignedBoxBounds;

/**
 * Class for anchoring the position of items within the frame.
 * Anchoring is when the position of the item is defined relative
 * to the edge of the frame instead of being defined in absolute
 * coordinates. Can't be anchored to the left and right edge at
 * the same time, nor the top and bottom edge at the same time.
 * 
 * @author cts16
 */
public class Anchoring {

        /** The relative distance from the left or right edge (null means unanchored). */
        private Integer _xAnchor = null;
        /** The relative distance from the top or bottom edge (null means unanchored). */
        private Integer _yAnchor = null;
        /** Whether the x-anchor is relative to the left or right edge. */
        private boolean _left = true;
        /** Whether the y-anchor is relative to the top or bottom edge. */
        private boolean _top = true;
        
        public Anchoring()
        {
        }
        
        public void setXAnchor(Integer offset, boolean left)
        {
                _xAnchor = offset;
                _left = left;
        }
        
        public void setYAnchor(Integer offset, boolean top)
        {
                _yAnchor = offset;
                _top = top;
        }
        
        public void setXAnchor(Anchoring other)
        {
                if (other == null) return;
                
                setXAnchor(other._xAnchor, other._left);
        }

        public void setYAnchor(Anchoring other)
        {
                if (other == null) return;
                
                setYAnchor(other._yAnchor, other._top);
        }
        
        public void setLeftAnchor(Integer offset)
        {
                setXAnchor(offset, true);
        }
        
        public void setRightAnchor(Integer offset)
        {
                setXAnchor(offset, false);
        }
        
        public void setTopAnchor(Integer offset)
        {
                setYAnchor(offset, true);
        }
        
        public void setBottomAnchor(Integer offset)
        {
                setYAnchor(offset, false);
        }
        
        public void removeXAnchor()
        {
                setXAnchor(null, _left);
        }
        
        public void removeYAnchor()
        {
                setYAnchor(null, _top);
        }
        
        public void removeAllAnchors()
        {
                removeXAnchor();
                removeYAnchor();
        }
        
        public Integer getXPositionInBox(AxisAlignedBoxBounds box)
        {
                if (box == null || _xAnchor == null) return null;
                
                if (_left) {
                        return box.getMinX() + _xAnchor;
                } else {
                        return box.getMaxX() - _xAnchor;
                }
        }
        
        public Integer getYPositionInBox(AxisAlignedBoxBounds box)
        {
                if (box == null || _yAnchor == null) return null;
                
                if (_top) {
                        return box.getMinY() + _yAnchor;
                } else {
                        return box.getMaxY() - _yAnchor;
                }
        }
        
        public Point getPositionInBox(AxisAlignedBoxBounds box)
        {
                Integer x = getXPositionInBox(box);
                Integer y = getYPositionInBox(box);
                
                if (x == null || y == null) return null;
                
                return new Point(x, y);
        }
        
        public boolean isXAnchored()
        {
                return _xAnchor != null;
        }
        
        public boolean isYAnchored()
        {
                return _yAnchor != null;
        }
        
        public boolean isAnchored()
        {
                return isXAnchored() || isYAnchored();
        }
        
        public Integer getLeftAnchor()
        {
                return _left ? _xAnchor : null;
        }
        
        public Integer getRightAnchor()
        {
                return !_left ? _xAnchor : null;
        }
        
        public Integer getTopAnchor()
        {
                return _top ? _yAnchor : null;
        }
        
        public Integer getBottomAnchor()
        {
                return !_top ? _yAnchor : null;
        }
}