/*
    Cmp3 works by spawning a manager process that takes care of playing the
    songs while the regular process worries about the actual playlist.
    This file contains the manager process.
*/

#include"cmp3manager.h"

FILE *debugfile;


/* XXX - debug stuff */
void startdebug()
{
	#ifdef CMP3_DEBUG
    debugfile = fopen(CMP3_LOGFILE, "a");
    setbuf(debugfile, NULL);
	#else /* CMP3_DEBUG */
    debugfile = fopen("/dev/null", "w");
    return;
	#endif /* CMP3_DEBUG */
}


/**************************
	MANAGEIT
	runs in a separate forked process, 
	manages the mp3 process
**************************/
void manageit()
{
	/*     setpgrp(); */
    shmptr = (shmdata_t*) shmat(shmid,NULL,0);
    if (shmptr < 0) {
        perror("can't attach shared memory");
        dienow(1);
    }
    shmptr->managpid = getpid();
    shmptr->listlen = 0;
    shmptr->pid = 0;
    shmptr->pltail = shmptr->plhead;
    signal(SIGUSR1,listnext); /* why is this not Signal?? */
    Signal(SIGCHLD,listnext);
    Signal(SIGINT,dienow);
    Signal(SIGTERM,dienow);

    startdebug();
    if (debugfile)
        fprintf(debugfile, "Initialized manager process %d\n", getpid());
    
    while (1)
        /*  oh, oh, oh, oh, stayin' alive, stayin' alive */
		/* FIXME: what happens if there IS no stdin? i.e. tty goes away? */
        select(0,NULL,NULL,NULL,NULL);
    exit(0);
}

/****************************************** 
	LISTNEXT
	plays the next file in the list. 
*******************************************/
void listnext(int signum)
{
    int pid;
	
	/* first reap dead pid's (HACK!) */
	if(kill(shmptr->pid,0)){
		shmptr->pid = 0;
	}

    if (shmptr->pause)
        return;

    if (signum==SIGCHLD) {
        while(waitpid(-1,NULL,WNOHANG) > 0)
            ;
        if ((shmptr->listlen > 1)) {

            if (shmptr->repeat == 1) {
                pl_addentry(shmptr->plhead);
            }
            pl_delentry(shmptr->plhead);
        } else {
            if (shmptr->repeat != 1) {
                if (shmptr->using == 0) {
                    dienow(1);
                } else {
                    shmptr->listlen = 0;
                    shmptr->pltail = shmptr->plhead;
                    return;
                }
            } else {
                /* In repeat mode, keep playing */
            }
        }
        shmptr->pid=0;
		/* old sysv style, must reset this here */
        Signal(SIGCHLD,listnext);
    } else {
		/* FIXME: ok, this must be where it is returning cause pid full? */
        if (shmptr->pid) {
			if(kill(shmptr->pid, 0) ){
				shmptr->pid = 0;
			}
			return;
		}
		/* old sysv style, must reset this here */
        signal(SIGUSR1,listnext);
    }
    if (shmptr->listlen > 0) {
		/* check for file type, launch either mpg123 or ogg123 */
		if (Strcmp(shmptr->plhead+(strlen(shmptr->plhead)-4),".mp3") == 0){
			pid = fork();
			if (pid == -1) {
				perror("Cant fork");
				exit(0);
			}
			if (pid==0) {
				int returned=0;

				sleep(1);
				fclose(stdin);

				/* Route all mpg123 output from stderr to logfile */
				if (debugfile) {
					dup2(fileno(debugfile), fileno(stderr));
					dup2(fileno(debugfile), fileno(stdout));
				} else {
					fclose(stderr);
				}

					returned = execlp(EXEC_LOC,
						  "mpg123",
						  EXEC_PARAMS
						  shmptr->plhead, 0);

			

				if (returned != 0) {
					fprintf(debugfile, "execlp failed on %s with errno = %d\n",
						shmptr->plhead, errno);
				}

				exit(0);
		   }
		   shmptr->pid=pid;
		} else if (Strcmp(shmptr->plhead+(strlen(shmptr->plhead)-4),".ogg") == 0){
			pid = fork();
			if (pid == -1) {
				perror("Cant fork");
				exit(0);
			}
			if (pid==0) {
				int returned=0;

				sleep(1);
				fclose(stdin);

				/* Route all mpg123 output from stderr to logfile */
				if (debugfile) {
					dup2(fileno(debugfile), fileno(stderr));
					dup2(fileno(debugfile), fileno(stdout));
				} else {
					fclose(stderr);
				}


				returned = execlp(OGG_LOC,
					  "ogg123",
					  OGG_PARAMS
					  shmptr->plhead, 0);
			

				if (returned != 0) {
					fprintf(debugfile, "execlp failed on %s with errno = %d\n",
						shmptr->plhead, errno);
				}

				exit(0);
		   }
		   shmptr->pid=pid;
		} else {
			fprintf(debugfile, "listnext: %s is not an mp3 or ogg file\n",
				shmptr->plhead);
			return;
		}  /* end ogg/mp3 contingencies */
	} /* end listlen > 0 */
} /* END LISTNEXT */

void dienow(int diedude)
{
    if (shmptr->pause == 1)
        kill(shmptr->pid, SIGCONT);
    if (shmptr->pid)
        kill(shmptr->pid,SIGINT);

    fprintf(debugfile, "Exiting manager process %d\n", getpid());
    fclose(debugfile);

    if (shmdt((char*)shmptr) < 0)
        perror("can't detach shared memory");
    if (shmctl(shmid, IPC_RMID, (struct shmid_ds *) 0) < 0)
        perror("can't remove shared memory");

  exit(1);
}

/* EOF */