/* 
GeoGebra - Dynamic Mathematics for Everyone
http://www.geogebra.org

This file is part of GeoGebra.

This program is free software; you can redistribute it and/or modify it 
under the terms of the GNU General Public License as published by 
the Free Software Foundation.

 */

package org.geogebra.common.kernel.advanced;

import org.geogebra.common.kernel.Construction;
import org.geogebra.common.kernel.algos.AlgoElement;
import org.geogebra.common.kernel.commands.Commands;
import org.geogebra.common.kernel.geos.GeoElement;
import org.geogebra.common.kernel.geos.GeoNumberValue;
import org.geogebra.common.kernel.geos.GeoText;

/**
 * Handles rotated texts
 * 
 * @author Michael
 *
 */

public class AlgoRotateText extends AlgoElement {

	private GeoText text; // output
	private GeoText args; // input
	private GeoNumberValue angle; // input

	private StringBuilder sb = new StringBuilder();

	/**
	 * Creates new text rotation algo
	 * 
	 * @param cons
	 *            construction
	 * @param label
	 *            label for output
	 * @param args
	 *            input text
	 * @param angle
	 *            angle of rotation
	 */
	public AlgoRotateText(Construction cons, String label, GeoText args,
			GeoNumberValue angle) {
		this(cons, args, angle);
		text.setLabel(label);
	}

	/**
	 * Creates new unlabeled text rotation algo
	 * 
	 * @param cons
	 *            construction
	 * @param args
	 *            input text
	 * @param angle
	 *            angle of rotation
	 */
	AlgoRotateText(Construction cons, GeoText args, GeoNumberValue angle) {
		super(cons);
		this.args = args;
		this.angle = angle;

		text = new GeoText(cons);
		text.setIsTextCommand(true); // stop editing as text

		setInputOutput();
		compute();
	}

	@Override
	public Commands getClassName() {
		return Commands.RotateText;
	}

	@Override
	protected void setInputOutput() {
		input = new GeoElement[2];
		input[0] = args;
		input[1] = angle.toGeoElement();

		args.addTextDescendant(text);

		setOutputLength(1);
		setOutput(0, text);
		setDependencies(); // done by AlgoElement
	}

	/**
	 * Returns the resulting text
	 * 
	 * @return resulting text
	 */
	public GeoText getResult() {
		return text;
	}

	@Override
	public final void compute() {
		if (!args.isDefined() || !angle.isDefined() || angle.isInfinite()) {
			text.setTextString("");
			return;
		}

		sb.setLength(0);
		appendRotatedText(sb, args, angle.getDouble() * 180 / Math.PI);

		text.setTextString(sb.toString());
		text.setLaTeX(true, false);
		text.setSerifFont(args.isSerifFont());
	}

	/**
	 * Appends LaTeX command for the rotated text to the string builder.
	 * 
	 * @param sbuilder
	 *            string builder
	 * @param text
	 *            text
	 * @param degrees
	 *            rotation algo
	 */
	public static void appendRotatedText(StringBuilder sbuilder, GeoText text,
			double degrees) {
		boolean latex = text.isLaTeX();
		sbuilder.append("\\rotatebox{");
		sbuilder.append(degrees); // convert to degrees
		sbuilder.append("}{ ");
		if (!latex) {
			sbuilder.append("\\text{ ");
		}
		sbuilder.append(text.getTextString());
		if (!latex) {
			sbuilder.append(" } ");
		}
		sbuilder.append(" }");
	}

	@Override
	public boolean isLaTeXTextCommand() {
		return true;
	}

}