/* Copyright (c) 2002-2004 by Stanley M. Swanson.
   Distributed under the GNU General Public License, version 2 (GPL v2). */
/* vamp_loops.c from midivamp.c  035.26 */

# include "globals.h"

# if (0) 
void print_help(void)   /* print contents of help[] */
{ int i; 
  for (i=0; i<MXHELP; i++) printf("%s\n",help[i]);
      printf("\n"); }
# endif


void generate_loops(char *midiout)
{  int i,j,k,m,n,tone,dur,vol,previ,accent,meas,chan,which,prog,lid,drum,key;
   char  *mtrk = "MTrk", i4[4];
   int *loop, *varptr, lix, lmax, lixin,
     *pntrs[10] = { &dur, &lid, &accent, &which, &key };

   /* initialize to single elements, possibly not looped */
   key = key_list[3]; accent = accent_list[3]; 
   which = instrument_list[3]; 
       quantum = 120; /* duration of quarter note ???  */

 /* generate midi file */
   midi_file_header(1,2,quantum,midiout);
   midi_info(midiout);

   nout = 0; /* byte count in bout[] */

   /* default looping:  inner [rtv] l a (k) i = outer */
   /* The looping code is obscure because of the possibility of altering
      the order of the loops with the 'o' command.  Hence pointers to
      the appropriate interation list and controlled variable are put
      into loopadr[] and loop_ptr[] depending on the contents of order_list[] 
      The tone and velocity are accessed in step with rhythm.
   */

       loop_ptr[0] = &dur;    loop_ptr[1] = &lid; /* loop id (ignored) */   
       loop_ptr[2] = &accent;    loop_ptr[3] = &which; 
    for (j=0; j<order_list[1]; j++) { k = order_list[j+3];
                  loopaddr[j] = order_addr[k]; loop_ptr[j] = pntrs[k]; }


   lix = lmax = 4;
   while (lix<=lmax) {   lixin = lix; 
     while (lix>0)  /* initialize loops */
     { lix--; loop = loopaddr[lix]; varptr = loop_ptr[lix];
       if (loop[0]) { loop[2] = loop[3]; *varptr = loop[2]; }
       else { loop[2] = 0; *varptr = loop[3]; } 
        if (Q_VERBOSE>6 && V_CLASS==6) 
	  printf("init lix %d ix %d value %4d\n",lix,loop[2],*varptr); 
     }  /* while (lix>0) initialize */

     /* slow loop midi changes... */
     if (lixin>2) {  meas = tictoc = previ = 0;  chan = 0; drum = 0;
          prog = which - 1;   /* program is external instrument - 1 */
     if (which>127){ chan = 9; drum = which - 100; prog = 0;
               if (drum<35) drum = 35; if (drum>81) drum = 81;  }
	  /* Timidity drums play on channel 9, tones 35 - 81 coded as
	      instruments 135...181 in this program   */
                     delta(0); change(0xC,chan,prog); /* instrument */ }

     n = loop[2] + 3;   /* index into tone_list, veloc_list parallel to rhythm_list */
   
      previ = tictoc/quantum;
      tone = tone_list[n] + key;  /* default key of C */
      if (drum) tone = drum;  /* percussion */
      vol = veloc_list[n];

      if (vol>1000) { k = vol / 1000;  vol -= k*1000;
      /* strip accent markers: 2000==primary, 1000==secondary */
             if (k==2) vol += accent; if (k==1) vol += accent/2; 
	     if (vol>127) vol = 127;    }  /* if (vol>1000) */

            tictoc += dur;

 if (Q_VERBOSE>1 && V_CLASS==6) 
   printf(" tone %3d vol %3d duration %3d loop %d  instrument %3d\n",
		      tone, vol, dur, lid, which);

	delta(0);    command(0x9,chan,tone,vol);
	delta(dur);  command(0x8,chan,tone,0); 
   

# if (0)
	if (vol>=0) {  /* start and stop note or rest */
        	delta(0);    command(0x9,chan,tone,vol);
	        delta(dur);  command(0x8,chan,tone,0); }

	if (vol == (-1) )   /* measure bar seen */
	  { if (tictoc>0 && Q_VERBOSE>1 && V_CLASS==6) 
            printf("measure  %3d  notes %4d  duration %4d  nout %5d\n",
				 meas,previ,tictoc,nout);
             meas++; accent += 0;     tictoc = 0; }  
      /* for (n...npitch) music loop  */
      
# endif

     /* iterate and check limits */
     lixin = lix - 1;
     while (lix>lixin) { lixin = lix;
   if (Q_VERBOSE>6 && V_CLASS==6)  
            printf("incr lix %d ix %d  value %4d\n",lix,loop[2],*varptr);  
       if (loop[0]) { loop[2] += loop[5]; 
         if (loop[2]<loop[4]) *varptr = loop[2]; else lix++; }
       else { k = loop[2] += 1; 
           if (k<loop[1]) *varptr = loop[k+3]; else lix++; }
       if (lix>=lmax) { lix = lmax + 1; break; }  /* final escape */
       if (lix>0) { loop = loopaddr[lix]; varptr = loop_ptr[lix]; }
   if (Q_VERBOSE>6 && V_CLASS==6)  
           printf("incr end lix %d value ix %d %4d\n",lix,loop[2],*varptr); 
     }  /* while (lix>lixin) */
   } /* while (lix<=lmax) */


      delta(100); shout(0xFF2F); delta(0); /* end of track */

  if (fout) {
      fwrite(mtrk,1,4,fout); 
      i = nout;  lowendian(4,(char*)&i,i4);  fwrite(i4,1,4,fout); 
      fwrite(bout,1,nout,fout); 
	fclose(fout);
     }  
     printf(" command trk length %d  hex %x oct %o \n",nout,nout,nout); 

}

void session_prefix(void)
{ int ncs;  time_t now; char buf[60];
      printf("log file (and loop output prefix): ");
          dot_sess = ncs = finstring(session,50,stdin);
	                 commenta[0] = commentb[0] = kc = 0;
if (ncs>0) {  /* loops to study options     print_help(); */ 
             session[ncs] = '.';  session[ncs+1] = 'l';  
             session[ncs+2] = 'o';  session[ncs+3] = 'g';  session[ncs+4] = 0; 
	     flog = fopen(session,"r");
	     if (flog) { printf("existing session prefix... open append\n");
	                 fclose(flog); flog = fopen(session,"a"); }
	     else flog = fopen(session,"w");
	     if (flog) { now = time(NULL); 
	        strftime(buf,60,"%H:%M:%S on %A, %d %B %Y",localtime(&now));
	        printf("opened log file: %s \n",session);
	        fprintf(flog,"===== opened %s\n",buf); } 
	     else printf("log file not opened\n");

             session[ncs+4] = '.';  session[ncs+5] = 'm';  
             session[ncs+6] = 'i';  session[ncs+7] = 'd';  session[ncs+8] = 0; 
    }
       /* prepare for sequence number midi_out_number in session[ncs:ncs+3] */
	     at_file = 0; fin[at_file] = stdin; 
} /* session_prefix() */

int loop_in(void)
{ int j,k,m,n, in_at = at_file, ncs = dot_sess;
  char *data=line+lch+2, *token, *file;  

       copy_line(); token = data = file = NULL; 
     token = find_token(&tok_start);  lch = tok_start - token_buf;
     if (!token) return;  data = line + lch;
     file  = find_token(&tok_start);

   switch(token[0]) {
       case '?': print_help(); break;
       case '#': if (commenta[0]==0) strcpy(commenta,line); 
		     else if (commentb[0]==0) strcpy(commentb,line); 
		 break;  /* comment */
/*
       case '@': filin = new_file(line+1,"r"); k = stack_files(filin);
		 break;
*/
       case 'g': sprintf(session+ncs,"%4d",ksession+1000); session[ncs]='.';
		 ksession++;
		 if (file) { generate_loops(file); spawn_play(file); } 
		 else { generate_loops(session); spawn_play(session); }
		    commenta[0] = commentb[0] = kc = 0; break;
       case 'p':  if (file) spawn_play(file); 
		   break;  /* case pid>0 continue execution in parent */ 
		   /*       case 'q': exit(0); */  /* quit program */  
       case 'a': scan_list(accent_list,data); break;
       case 'c': scan_list(controls[kc],data);
		  if (kc<9) kc++; break;
       case 'i': scan_list(instrument_list,data); break;
       case 'k': scan_list(key_list,data); break;
       case 'l': scan_list(loop_list,data); break;
       case 'o':   k = 0; for (j=lch+2; j<n; j++) if (line[j] != ' ')
	 { m = -1; if (line[j]=='r') m = OX_RHYTHM; 
		   else if (line[j]=='l') m = OX_LOOP; 
		   else if (line[j]=='a') m = OX_ACCENT; 
		   else if (line[j]=='i') m = OX_INSTR; 
		   else if (line[j]=='k') m = OX_KEY; 
	      if (m> (-1)) { order_list[k+3] = m; k++; }
	 } 
	 if (k<1) printf("no loops in order_list...keep old\n");
	 else order_list[1] = k;  break;
       case 'r': scan_list(rhythm_list,data); break;
       case 't': scan_list(tone_list,data); break;
       case 'v': scan_list(veloc_list,data); break;
       case 'd': printf("dump unimplemented\n"); 
       case '%': break;  /* just a comment */  
       case 0: break;
      default:  printf("unhandled loop option %s\n",line);
    }  /* switch (line[0]) */

   /*   } */   /* while (1) */
 }   /* end loop_in() */