/* 
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.cas;

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.GeoFunction;
import org.geogebra.common.kernel.geos.GeoList;
import org.geogebra.common.plugin.EuclidianStyleConstants;

/**
 * Find asymptotes
 * 
 * @author Michael Borcherds
 */
public class AlgoAsymptoteFunction extends AlgoElement {

	private GeoFunction f; // input
	private GeoList g; // output

	private StringBuilder sb = new StringBuilder();

	/**
	 * Asymptotes for function
	 * 
	 * @param cons
	 *            construction
	 * @param label
	 *            label for output
	 * @param f
	 *            function
	 */
	public AlgoAsymptoteFunction(Construction cons, String label,
			GeoFunction f) {
		super(cons);
		this.f = f;

		g = new GeoList(cons);
		g.setLineType(EuclidianStyleConstants.LINE_TYPE_DASHED_SHORT);
		g.setTypeStringForXML("line");
		setInputOutput(); // for AlgoElement
		compute();
		g.setLabel(label);
	}

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

	// for AlgoElement
	@Override
	protected void setInputOutput() {
		input = new GeoElement[1];
		input[0] = f;

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

	/**
	 * @return list of asymptotes
	 */
	public GeoList getResult() {
		return g;
	}

	@Override
	public final void compute() {
		if (!f.isDefined()) {
			g.setUndefined();
			return;
		}

		try {
			sb.setLength(0);
			sb.append("{");
			f.getHorizontalPositiveAsymptote(f, sb);
			f.getHorizontalNegativeAsymptote(f, sb);

			f.getDiagonalPositiveAsymptote(f, sb);
			f.getDiagonalNegativeAsymptote(f, sb);

			f.getVerticalAsymptotes(f, sb, false);

			sb.append("}");

			// Application.debug(sb.toString());
			g.set(kernel.getAlgebraProcessor().evaluateToList(sb.toString()));
		} catch (Throwable th) {
			g.setUndefined();
		}
	}

}