/**
 * This program continuously plays a scale, but the timing is based on the
 * System Clock UTC.
 *
 * This means that if this program is executed on two different machines which
 * have their System Clocks synchronised (eg. by NTP) then playback of the two
 * scales should be perfectly in sync.
 *
 * Author: adambuckley@gmx.net
 * Version: $Id: synctest.c,v 1.2 2002/05/23 12:13:55 adam Exp $
 */

/**
 * This source code is copyright (c) 2002 Adam Buckley, <adambuckley@gmx.net>.
 *
 * This source code 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; either version 2 of the License, or (at your option) 
 * any later version.
 *
 * This source code 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 Public License for 
 * more details.
 *
 * The GNU General Public License can be found at
 * http://www.gnu.org/licenses/gpl.html
 */

#include "utc.c"
#include "beep.c"
#include "midi.c"
#include <getopt.h>
#include <signal.h>



// Constant definitions
// --------------------

#define USE_PC_SPEAKER 0
#define USE_MIDI 1



// Global variables
// ----------------

// Which mode are we in?  PC speaker or MIDI?
int mode = USE_MIDI;



/**
 * Finish
 */
void finish()
{
	if(mode==USE_PC_SPEAKER) beepOff();
	// ToDo: if(mode==USE_MIDI) {Some MIDI clean-up}
	exit(0);
}



/**
 * main
 */
int main(int argc, char **argv)
{
	int i;
	unsigned char previousNote = 0;
	char* dev = "/dev/sequencer2";
	char command;
	
	
	// How long do we pause between playing notes?
	long pause = 400000; // 0.4 second
	
	// Which notes do we play?
	int notes[] = {60, 62, 64, 65, 67, 69, 71, 72};
	int numberOfNotes = sizeof(notes) / sizeof(notes[0]);
	
	// If we use MIDI, what settings do we use?
	int device = 0, channel = 0, velocity = 100;
	
	// The onset time in microseconds UTC of the next note
	// This code sets t to the beginning of the bar which is playing 'now'
	long long t = (long long) (getUtc() / (long long) (pause*numberOfNotes))*pause*numberOfNotes;
	
	
	// Trap exit conditions
	signal(SIGINT, finish);  // Trap CTRL-C
	signal(SIGTERM, finish);  // Trap 'kill pid'



	// Process command line
	while((command = getopt(argc, argv, "?mb")) != -1)
	{
		switch(command)
		{
			case 'm':
				mode = USE_MIDI;
				break;

			case 'b':
				mode = USE_PC_SPEAKER;
				break;
				
			case '?':
				printf("synctest -[m|b]\n\t-m use MIDI playback\n\t-b use the PC speaker (must have root privileges)\n");
				exit(0);
				break;
			
			default:
				break;
		}
	}


		
	// Start MIDI
	if(mode==USE_MIDI) 
	{
		startMidi(dev, device);
		// ToDo: Reset?
	}
	
	
	// Start the test
	while(1)
	{
		for(i=0; i<numberOfNotes; i++)
		{
			// Only play notes which we have to wait for
			// This solves the problem of listening to the few 'late' notes
			// (since this bar began) all in one go.
			// ToDo: Integrate this into the jump algorithm above?
			if(t > getUtc())
			{
				waitUntil(t);
				
				if(mode==USE_PC_SPEAKER)
				{
					beepNote(notes[i], 100000);
				}
				else if(mode==USE_MIDI)
				{
					sendVoiceMessage(device, MIDI_NOTEOFF, channel, previousNote, velocity, FALSE);
					sendVoiceMessage(device, MIDI_NOTEON, channel, notes[i], velocity, TRUE);
					previousNote = notes[i];
				}
			}
			
			t = t + pause;
		}
	}
	
	// Superflous code?
	if(mode==USE_MIDI) stopMidi();
	return 0;
}