source: trunk/src/org/expeditee/gio/TextLayoutManager.java@ 1415

package org.expeditee.gio;

import java.util.List;

import org.expeditee.core.Font;
import org.expeditee.core.Line;
import org.expeditee.core.Point;
import org.expeditee.core.TextHitInfo;
import org.expeditee.core.TextLayout;
import org.expeditee.core.bounds.AxisAlignedBoxBounds;

/** TODO: Comment. cts16 */
public abstract class TextLayoutManager {

        public abstract List<TextLayout> layoutString(String string, Font font, Point start, Line[] lineBreakers, int widthLimit, int lineSpacing, boolean dontBreakWords, boolean fullJustify);
        
        public List<TextLayout> layoutStringRelative(String string, Font font, int widthLimit, int lineSpacing, boolean dontBreakWords, boolean fullJustify)
        {
                return layoutString(string, font, Point.ORIGIN.clone(), null, widthLimit, lineSpacing, dontBreakWords, fullJustify);
        }
        
        public TextLayout layoutStringSimple(String string, Font font)
        {
                List<TextLayout> layouts = layoutStringRelative(string, font, Integer.MAX_VALUE, 0, true, false);
                if (layouts == null || layouts.size() == 0) return null;
                return layouts.get(0);
        }
        
        public abstract float getAdvance(TextLayout layout);
        public abstract int getCharacterCount(TextLayout layout);
        public abstract TextHitInfo getNextLeftHit(TextLayout layout, int offset);
        public abstract TextHitInfo getNextLeftHit(TextLayout layout, TextHitInfo hit);
        public abstract TextHitInfo getNextRightHit(TextLayout layout, int offset);
        public abstract TextHitInfo getNextRightHit(TextLayout layout, TextHitInfo hit);
        public abstract float[] getCaretInfo(TextLayout layout, TextHitInfo hit);
        public abstract AxisAlignedBoxBounds getPixelBounds(TextLayout layout, float x, float y);
        public abstract AxisAlignedBoxBounds getLogicalHighlightShape(TextLayout layout, int firstEndpoint, int secondEndpoint);
        public abstract float getAscent(TextLayout layout);
        public abstract float getDescent(TextLayout layout);
        public abstract float getLeading(TextLayout layout);
        public abstract int getStringWidth(Font font, String string);
        public abstract TextHitInfo hitTestChar(TextLayout layout, float x, float y);
        
        public abstract void releaseLayout(TextLayout layout);
        
        public void releaseLayouts(List<TextLayout> layouts)
        {
                if (layouts == null) return;
                
                for (TextLayout layout : layouts) {
                        releaseLayout(layout);
                }
        }
        
        /**
         * Calculates the maximum possible distance a line can extend to the right from a given point
         * without crossing any of the lines in the given array.
         * 
         * @param p
         *              The coordinates of the beginning point.
         * 
         * @param lines
         *              The lines that should stop the extension.
         * 
         * @return
         *              The length of the extended line.
         */
        public float getLineWidth(Point p, Line[] lines)
        {
                float width = (float) Integer.MAX_VALUE;
                for(Line l : lines) {
                        // check for lines that cross over our y
                        if((l.getFirstEnd().getY() >= p.getY() && l.getSecondEnd().getY() <= p.getY()) || (l.getFirstEnd().getY() <= p.getY() && l.getSecondEnd().getY() >= p.getY())) {
                                float dX = l.getFirstEnd().getX() - l.getSecondEnd().getX();
                                float dY = l.getFirstEnd().getY() - l.getSecondEnd().getY();
                                float newWidth;
                                if(dX == 0) {
                                        newWidth = l.getFirstEnd().getX();
                                } else if(dY == 0) {
                                        newWidth = Math.min(l.getFirstEnd().getX(), l.getSecondEnd().getX());
                                } else {
                                        newWidth = l.getFirstEnd().getX() + (p.getY() - l.getFirstEnd().getY()) * dX / dY;
                                }
                                if(newWidth < p.getX()) {
                                        continue;
                                }
                                if(newWidth < width) {
                                        width = newWidth;
                                }
                        }
                }
                return width - p.getX();
        }
        
}