/*
 * JFugue - API for Music Programming
 * Copyright (C) 2003-2008  David Koelle
 *
 * http://www.jfugue.org
 *
 * This library 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 2.1 of the License, or any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

package org.jfugue;

import java.util.HashMap;
import java.util.Map;

/**
 * Facilitates playing microtonal music - Indian, Turkish, Indonesian, etc.
 * styles. Also useful for performing slides and other effects that rely on
 * "the notes in between the notes".
 *
 * This feature is covered in detail in "The Complete Guide to JFugue"
 *
 * @author David Koelle
 * @version 3.0
 * @version 4.0 - renamed from MicrotoneHelper; mictoronal notes now encased in
 *          angle brackets instead of square brackets, for consistency
 */
public class MicrotoneNotation {
	private Map<String, Double> keyToFreqDict;
	private Map<String, String> keyToMusicStringDict;

	public MicrotoneNotation() {
		keyToFreqDict = new HashMap<String, Double>();
		keyToMusicStringDict = new HashMap<String, String>();
	}

	public void put(String key, double freq) {
		keyToFreqDict.put(key, freq);
		keyToMusicStringDict.put(key, convertFrequencyToMusicString(freq));
	}

	public double get(String key) {
		return keyToFreqDict.get(key);
	}

	public String getMusicString(String key) {
		return keyToMusicStringDict.get(key);
	}

	/**
	 * Converts the given frequency to a music string that involves the Pitch
	 * Wheel and notes to create the frequency
	 * 
	 * @param freq
	 *            the frequency
	 * @return a MusicString that represents the frequency
	 */
	public static String convertFrequencyToMusicString(double freq) {
		double totalCents = 1200 * Math.log(freq / 16.3515978312876)
				/ Math.log(2);
		double octave = Math.round(totalCents / 1200.0);
		double semitoneCents = totalCents - (octave * 1200.0);
		double semitone = Math.round(semitoneCents / 100.0);
		double cents = 8192 + Math.round(semitoneCents - (semitone * 100));

		double note = ((octave + 1) * 12) + semitone; // This gives a MIDI
														// value, 0 - 128
		if (note > 127) {
			note = 127;
		}

		StringBuilder buffy = new StringBuilder();
		buffy.append("&");
		buffy.append((int) cents);
		buffy.append(" [");
		buffy.append((int) note);
		buffy.append("]");
		return buffy.toString();
	}

	public static String getResetPitchWheelString() {
		return (" &8192"); // Reset the pitch wheel. 8192 = original pitch wheel
							// position
	}

	public Pattern getPattern(String notation) {
		StringBuilder buddy = new StringBuilder();
		String[] tokens = notation.split(" ");

		// Go through the Pattern, and replace known microtone keys with
		// microtone music strings
		for (int i = 0; i < tokens.length; i++) {
			if ((tokens[i].length() > 0) && (tokens[i].charAt(0) == '<')) {
				int end = tokens[i].indexOf('>');
				String possibleKey = tokens[i].substring(1, end);
				if (keyToMusicStringDict.containsKey(possibleKey)) {
					buddy.append(keyToMusicStringDict.get(possibleKey));
					buddy.append(
							tokens[i].substring(end + 1, tokens[i].length())); // Add
																				// the
																				// rest
																				// of
																				// the
																				// token
					buddy.append(getResetPitchWheelString());
				} else {
					buddy.append(tokens[i]);
				}
			} else {
				buddy.append(tokens[i]);
			}
			buddy.append(" ");
		}

		return new Pattern(buddy.toString());
	}
}