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();
	}
	
}