/**
 * Copyright 2010-2013 Jingjing Li.
 *
 * This file is part of jplot2d.
 *
 * jplot2d is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 *
 * jplot2d is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with jplot2d. If not, see .
 */
package org.jplot2d.axtick;

import java.text.Format;

/**
 * 
 * @author Jingjing Li
 * 
 */
public class LinearTickCalculator extends AbstractLinearTickCalculator {

	public LinearTickCalculator() {

	}

	protected DoubleInterval[] calcCandidateInterval(double rough) {
		int expn = (int) Math.floor(Math.log10(rough));
		double scale = Math.pow(10, expn);
		/* 1 <= rough/scale < 10 */
		double coeff = rough / scale;
		Int10expn itvA, itvB;
		if (coeff < 2) {
			itvA = new Int10expn(1, expn);
			itvB = new Int10expn(2, expn);
		} else if (coeff < 5) {
			itvA = new Int10expn(2, expn);
			itvB = new Int10expn(5, expn);
		} else {
			itvA = new Int10expn(5, expn);
			itvB = new Int10expn(1, expn + 1);
		}

		return new Int10expn[] { itvA, itvB };
	}

	public void calcValuesByTickNumber(int tickNumber, int minorTickNumber) {
		Int10expn intv = (Int10expn) calcInterval(tickNumber);

		if (minorTickNumber == AUTO_MINORTICK_NUMBER) {
			switch (intv.getCoefficient()) {
			case 1: /* the minor interval is 0.2 */
				minorNumber = 4;
				break;
			case 2: /* the minor interval is 0.5 */
				minorNumber = 3;
				break;
			case 5: /* the minor interval is 1 */
				minorNumber = 4;
				break;
			default:
				throw new java.lang.IllegalStateException();
			}
		} else {
			minorNumber = minorTickNumber;
		}

		calcValues(interval, 0, minorNumber);
	}

	@Override
	protected int calcMinorNumber(double interval) {

		int mag = (int) Math.floor(Math.log10(interval));
		double coefficient = interval / Math.pow(10, mag);
		double s1dcoef = Math.round(coefficient);
		/*
		 * if the coefficient contains more than 1 significant digit, ignore the minor number
		 */
		if (Math.abs(s1dcoef / coefficient - 1) > DOUBLE_PRECISION_TOLERANCE) {
			return 0;
		} else {
			switch ((int) s1dcoef) {
			case 1: /* the minor interval is 0.2 */
			case 10: /* the minor interval is 2 */
				return 4;
			case 2: /* the minor interval is 0.5 */
				return 3;
			case 3: /* the minor interval is 1 */
				return 2;
			case 4: /* the minor interval is 1 */
				return 3;
			case 5: /* the minor interval is 1 */
				return 4;
			case 6: /* the minor interval is 2 */
				return 2;
			case 7: /* the minor interval is 1 */
				return 6;
			case 8: /* the minor interval is 2 */
				return 3;
			case 9: /* the minor interval is 3 */
				return 2;
			default:
				return 0;
			}
		}
	}

	public String getLabelFormate() {
		return calcLabelFormatString(getValues());
	}

	public Format calcLabelTextFormat(Object canonicalValues) {
		return null;
	}

}