/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package javax.sound.midi;

import java.util.ArrayList;

import org.apache.harmony.sound.internal.nls.Messages;

public class Track {
    private ArrayList<MidiEvent> events; //vector of events contain in the Track
    
    private MidiEvent badEvent; //variable to save event which I try to add
                                //to empty Track; see description below
    
    private long tick; 
    
    Track() {
        /*
         * create an empty Track; new Track must contain only meta-event End of Track.
         * MetaMessage with MetaMessage.data contains -1, 47 and 0 is meta-event
         */
        events = new ArrayList<MidiEvent>();
        events.add(new MidiEvent(new MetaMessage(new byte[] {-1, 47, 0}), 0));
    }
    public boolean add(MidiEvent event) {
        //FIXME
        /*
         * Some words about badEvent.
         * When I write tests, I find following situation in the RI:
         * if I want to add to empty Track new event that is not meta-event End of Track,
         * I catch exception ArrayIndexOutOfBoundsException with meaning -1, and my
         * event doesn't add to Track, but meta-event adds. If I try to add the same 
         * event after it, method Track.add(MidiEvent) return 'false', and my event
         * doesn't add again. So, I want to delete this event and use method 
         * Track.remove(MidiEvent) for it, but it return 'false' too! And only after
         * this "shamanism" I can add this event to Track normally. 
         * And only for this situation I use variable badEvent. 
         * 
         * See test org.apache.harmony.sound.tests.javax.sound.midi.TrackTest 
         * for more details
         */
        
        /*
         * if event equals null or badEvent, this method return 'false'
         */
        if (event == null || event == badEvent) {
            return false;
        }
        /*
         * If event equals meta-event End of Track and Track in this moment
         * doesn't contain some events, i.e. Track.size() return 0, this 
         * event accrue to Track; 
         * if Track is not empty, but it doesn't contain meta-event, 
         * this event accrue to the end of Track;
         * in any case addition of this meta-event is successful, this method 
         * return 'true' even if meta-event End of Track already contains in the Track
         */
        if (event.getMessage().getMessage()[0] == -1 &&
                event.getMessage().getMessage()[1] == 47 &&
                event.getMessage().getMessage()[2] == 0 ) {
            if (events.size() == 0) {
                return events.add(event);
            }
            byte[] bt = events.get(events.size() - 1).getMessage().getMessage();
            if ((bt[0] != -1) && (bt[1] != 47) && (bt[2] != 0)) {
                return events.add(event);
            }         
            return true;
        }
        /*
         * after use method Track.add(MidiEvent) Track must contain meta-event
         * End of Track; so, at first I add this event to Track if it doesn't 
         * contain meta-event and parameter 'event' is not meta-event
         */
        if (events.size() == 0) {
            events.add(new MidiEvent(new MetaMessage(new byte[] {-1, 47, 0}), 0));
            badEvent = event;
            // sounds.01=-1
            throw new ArrayIndexOutOfBoundsException(Messages.getString("sound.01")); //$NON-NLS-1$
        }
        byte[] bt = events.get(events.size() - 1).getMessage().getMessage();
        if ((bt[0] != -1) && (bt[1] != 47) && (bt[2] != 0)) {
            events.add(new MidiEvent(new MetaMessage(new byte[] {-1, 47, 0}), 0));
        }
        
        if (events.contains(event)) {
            return false;
        } 
        
        /*
         * events in the Track must take up position in ascending ticks
         */
        if (events.size() == 1) {
            events.add(0, event);
        }
        for (int i = 0; i < events.size() - 1; i++ ) {
            if (events.get(i).getTick() <= event.getTick()) {
                continue;
            }
            events.add(i, event);
            break;
        }
        /*
         * method Track.ticks() return the biggest value of tick of all events
         * and save it even I remove event with the biggest values of tick
         */
        if (tick < event.getTick()) {
            tick = event.getTick();
        }
        return true;           
    }

    public MidiEvent get(int index) throws ArrayIndexOutOfBoundsException {
        if (index < 0 || index >= events.size()) {
            // sound.02=Index: {0}, Size: {1}
            throw new ArrayIndexOutOfBoundsException(Messages.getString("sound.02", index, events.size()));  //$NON-NLS-1$
        }
        return events.get(index);
    }

    public boolean remove(MidiEvent event) {
        /*
         * if I remove event that equals badEvent, I "delete" badEvent
         */
        if (event == badEvent) {
            badEvent = null;
            return false;
        }
        /*
         * method Track.ticks() always return the biggest value that ever has been
         * in the Track; so only when Track is empty Track.ticks() return 0 
         */
        if (events.remove(event)) {
            if (events.size() == 0) {
                tick = 0;
            }
            return true;
        }
        return false;
    }

    public int size() {
        return events.size();
    }

    public long ticks() {
        return tick;
    }
}