#include <u.h>
#include <libc.h>
#include <bio.h>
#include <thread.h>
#include "abuf.h"
#include "rollc.h"

enum {
	Argsmax = 8,
	Maxstack = 16384,
};

Channel *rollchan;

static int rfd;
static double beat;
static Biobuf bin;
static char *actions[] = {
	"none",
	"play",
	"repeat",
	"stop",
	"quit",
	0,
};

static int
lookup(char **keywords, char *s)
{
	int k;
	for(k=0; keywords[k]; k++)
		if(strcmp(keywords[k], s) == 0)
			return k;
	return -1;
}

static void 
parse(Action *act, char *line)
{
	char *argv[8];
	int argc;
	Note *note, **np;
	
	argc = tokenize(line, argv, 8);
	if(argc < 4)
		return;
	if(atoi(argv[3]) == 0){
		act->len = atof(argv[0]) * beat;
		return;
	}

	note = malloc(sizeof *note);
	note->t = atof(argv[0]) * beat;
	note->len = atof(argv[3]) * beat;
	note->vol = atoi(argv[2]);
	note->name = strdup(argv[1]);
	
	for(np=&act->notes; *np; np=&(*np)->next){
		if((*np)->t >= note->t)
			break;
	}
	note->next = *np;
	*np = note;
}

void
rollproc(void *)
{
	char *line;
	Action a;
	int k;
	
	Binit(&bin, rfd, OREAD);
	do{
		a.action = Aquit;
		a.notes = 0;
		a.len = 0;
		for(;;){
			line = Brdstr(&bin, '\n', 1);
			if(line == 0)
				break;
			k = lookup(actions, line);
			if(k != -1){
				a.action = k;
				break;
			}
			parse(&a, line);
			free(line);
		}
		send(rollchan, &a);
	}while(a.action != Aquit);
	Bterm(&bin);
	threadexits(0);
}

void
rollstart(char *path, double bpm)
{
	rollchan = chancreate(sizeof(Action), 16);
	if(path == 0)
		return;
	rfd = open(path, OREAD);
	if(rfd < 0)
		sysfatal("roll: %r");
	beat = SRATE * 60 / bpm / pow(2, 14);
	proccreate(rollproc, 0, Maxstack);
}


void
discardact(Action *a)
{
	Note *note, *next;
	for(note=a->notes; note; note=next){
		next = note->next;
		free(note->name);
		free(note);
	}
}

void
dumpact(Action *a)
{
	Note *note;
	fprint(2, "action=%s songlen=%d\n", actions[a->action], a->len);
	for(note=a->notes; note; note=note->next)
		fprint(2, "t=%d len=%d v=%d name=%s\n", 
			note->t, note->len, note->vol, note->name);
}