/* fmsynt plays the fm chip with MIDI messages from MIDI IN */
/* channel 10 goes directly to MIDI out                     */

#include <sbc.h>
#include <stdio.h>
#include <sbcmusic.h>
#include <bios.h>
#include <conio.h>
#include <dos.h>

extern void init_midi(void);
extern void exit_midi(void);
extern int get_midibyte(unsigned char * midiinbyte);
extern void out_midibyte(unsigned char midioutbyte);

const NoteOff1        = 128,
	  NoteOff16       = 143,
	  NoteOn1         = 144,
	  NoteOn16        = 159,
	  PolyPress1      = 160,
	  PolyPress16     = 175,
	  ControlChange1  = 176,
	  ControlChange16 = 191,
	  ProgramChange1  = 192,
	  ProgramChange16 = 207,
	  ChanPress1      = 208,
	  ChanPress16     = 223,
	  PitchWheel1     = 224,
	  PitchWheel16    = 239,
	  SysEx           = 240,
	  EOX             = 247 ;


unsigned char run_status_buf;

char channel_on[16];

char default_instr[16] =
		{   0x021,0x011,0x04C,0x000,0x0F1,0x0F2,0x063,0x072,
			0x000,0x000,0x004,0x000,0x000,0x000,0x000,0x000 };

char InstrBuf[128][16];

int numinstr;

int notedur;
unsigned char old_note,velocity,octave;
int note_stopped;
long far *ticks;
long tick_cntr;

main(int argc,char **argv)
{
unsigned char bMidiByte,note,channel,velocity,program_num;

	if(init(argc,argv[1]))
	{
		while(1)
		{
			if (get_midibyte(&bMidiByte))
			{

			 /*	out_midibyte(bMidiByte); */

				if(bMidiByte >= NoteOff1)
					run_status_buf = bMidiByte;
				else
				{
					channel = run_status_buf & 0xF;

					if((run_status_buf >= NoteOn1) && (run_status_buf <= NoteOn16))
					{
						while(! get_midibyte(&velocity));
					/*	out_midibyte(velocity); */

						if(channel_on[channel])
							fmplay(channel,bMidiByte,velocity);
					}
					else
					{
						if((run_status_buf >= ProgramChange1) && (run_status_buf <= ProgramChange16))
							sbfd_program_change(channel,bMidiByte);
					}
				}
			}

			if(! note_stopped)
				if(ticks[0]-tick_cntr > notedur)
					stop_note();

			if(kbhit())
				if(! process_key()) break;
		}
		sbfd_music_off();
		exit_midi();
		clrscr();
	}
}

int init(int argc,char *patchfile)
{
int i,j;

	if ( ! GetEnvSetting() )
	{
		if (sbc_check_card() & 4)
		{
			if (sbc_test_int())
			{
				init_midi();
				sbfd_init();

				ticks = MK_FP(0,0x46c);
				note_stopped = 1;
				velocity = 64;
				notedur = 20;
				octave = 5;

				for(i=0;i<16;i++)
					channel_on[i] = 1;

				for(i=0;i<128;i++)
					for(j=0;j<16;j++)
						InstrBuf[i][j]=default_instr[j];

				if(argc > 1)
					loadpatches2(patchfile);

				sbfd_instrument((char far*)InstrBuf);
				draw_screen();
			}
			else
			{
				printf("Error on interrupt.\n");
				return(0);
			}
		}
		else
		{
			printf("Sound Blaster Card not found or wrong I/O setting.\n") ;
			return(0);
		}
	}
	else
	{
		printf("BLASTER environment variable not set or incomplete or invalid.\n");
		return(0);
	}
	return(1);
}

draw_screen()
{
int i;
	clrscr();
	printf("*** FM MIDI Synth *** \n\n");
	printf("Channels enabled/disabled\n");
	printf("-------------------------\n\n");
	printf("0 1 2 3 4 5 6 7 8 9 A B C D E F\n\n");

	for(i=0;i<16;i++)
		printf("%X ",channel_on[i]);
}

int process_key()
{
int scan,modifiers;

	scan = (bioskey(0) >> 8) & 0xFF;
	modifiers = bioskey(2);

	if(scan == 1) return(0);

	if(modifiers & 8)
	{
		switch(scan) {
			case 45 : setduration();break;     /* Alt-X */
			case 47 : setveloc();break;        /* Alt-V */
			case 25 : loadpatch();break;       /* Alt-P */
			case 38 : loadpatches();break;     /* Alt-L */
			case 31 : savepatches();break;     /* Alt-S */

			case 120 : channel_on[1] = channel_on[1] ^ 1; break;
			case 121 : channel_on[2] = channel_on[2] ^ 1; break;
			case 122 : channel_on[3] = channel_on[3] ^ 1; break;
			case 123 : channel_on[4] = channel_on[4] ^ 1; break;
			case 124 : channel_on[5] = channel_on[5] ^ 1; break;
			case 125 : channel_on[6] = channel_on[6] ^ 1; break;
			case 126 : channel_on[7] = channel_on[7] ^ 1; break;
			case 127 : channel_on[8] = channel_on[8] ^ 1; break;
			case 128 : channel_on[9] = channel_on[9] ^ 1; break;
			case 129 : channel_on[0] = channel_on[0] ^ 1; break;
			case 30 : channel_on[10] = channel_on[10] ^ 1; break;
			case 48 : channel_on[11] = channel_on[11] ^ 1; break;
			case 46 : channel_on[12] = channel_on[12] ^ 1; break;
			case 32 : channel_on[13] = channel_on[13] ^ 1; break;
			case 18 : channel_on[14] = channel_on[14] ^ 1; break;
			case 33 : channel_on[15] = channel_on[15] ^ 1; break;
		}
		draw_screen();
	}
	else
	{
		switch(scan) {
			case 44 : playnote(0);break;                /* z */
			case 31 : playnote(1);break;                /* s */
			case 45 : playnote(2);break;                /* x */
			case 32 : playnote(3);break;               /* d */
			case 46 : playnote(4);break;               /* c */
			case 47 : playnote(5);break;               /* v */
			case 34 : playnote(6);break;               /* g */
			case 48 : playnote(7);break;               /* b */
			case 35 : playnote(8);break;               /* h */
			case 49 : playnote(9);break;               /* n */
			case 36 : playnote(10);break;               /* j */
			case 50 : playnote(11);break;               /* m */
			case 51 : playnote(12);break;               /* , */

			case 16 : playnote(12);break;               /* q */
			case 3  : playnote(13);break;              /* 2 */
			case 17 : playnote(14);break;             /* w */
			case 4  : playnote(15);break;             /* 3 */
			case 18 : playnote(16);break;             /* e */
			case 19 : playnote(17);break;              /* f */
			case 6  : playnote(18);break;             /* 5 */
			case 20 : playnote(19);break;             /* t */
			case 7  : playnote(20);break;             /* 6 */
			case 21 : playnote(21);break;            /* y */
			case 8  : playnote(22);break;           /* 7 */
			case 22 : playnote(23);break;           /* u */
			case 23 : playnote(24);break;           /* i */

			case 78 : if(octave < 7) octave++;break;
			case 74 : if(octave > 2) octave--;break;
		}
	}
	return(1);
}

loadpatch()
{
FILE* f;

char patchname[80],patchnumstr[10];

	clrscr();
	printf("Name of single patch to load: ");
	gets(patchname);
	printf("Patch number to load patch into (0-127): ");
	gets(patchnumstr);

	if(f=fopen(patchname,"rb"))
	{
		fread(&InstrBuf[atoi(patchnumstr)][0],16,1,f);
		fclose(f);
	}
	else
	{
		printf("Couldn't find %s!\n",patchname);
		delay(1000);
	}
	draw_screen();
}


loadpatches()
{
char patchsetname[80];

	clrscr();
	printf("Name of patch set to load: ");
	gets(patchsetname);

	loadpatches2(patchsetname);

	draw_screen();
}

loadpatches2(char *patchfile)
{
FILE* f;
int i;

	if(f = fopen(patchfile,"rb"))
	{
		for(i=0;i<128;i++)                     /* read instruments */
			fread(&InstrBuf[i][0],1,16,f);
		fclose(f);
	}
	else
	{
		printf("Couldn't find %s!\n",patchfile);
		delay(1000);
	}
}

savepatches()
{
FILE* f;
int i;
char patchsetname[80];

	clrscr();
	printf("Save patch set as: ");
	gets(patchsetname);

	f = fopen(patchsetname,"wb");

	for(i=0;i<128;i++)
		fwrite(&InstrBuf[i][0],1,16,f);

	fclose(f);

	draw_screen();
}

fmplay(unsigned char channel, unsigned char note, unsigned char velocity)
{
	if(velocity != 0)
	   sbfd_note_on(channel,note,velocity);
	else
		sbfd_note_off(channel,note,velocity);
}

setduration()
{
char notedurstr[10];
	printf("\nSet note length (times 55 ms): ");
	gets(notedurstr);
	notedur = atoi(notedurstr);
}

setveloc()
{
char velocstr[10];
	printf("\nSet velocity (0-127): ");
	gets(velocstr);
	velocity = atoi(velocstr);
}


playnote(unsigned char offs)
{
unsigned char note;

	if(! note_stopped)
		stop_note();

	note = (octave*12)+offs;

	out_midibyte(0x90);                          /* Note On channel 1 */
	out_midibyte(note);
	out_midibyte(velocity);

	tick_cntr = ticks[0];
	old_note = note;
	note_stopped = 0;
}

stop_note()
{
	out_midibyte(0x90);                          /* Note Off */
	out_midibyte(old_note);
	out_midibyte(0);
	note_stopped = 1;
}
.