/*
 * cs537 Project 1 - Shell
 *
 * Written by Stefan Strandberg (stefan@cs.wisc.edu)
 * $Id: main.c,v 1.8 2004/09/23 22:00:27 stefan Exp $
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/wait.h>
#include "shell.h"
#include "job.h"

/*
 * TODO:
 * 
 * Fix horrible memory leaks...they're better than they were, but they're still
 * there.
 *
 * Figure out why the heck my waitpid keeps getting -1.  Maybe I'm reaping
 * Wrong or something.  Meh.
 *
 */

int main(int argc, char *argv[]) {
	
	
	int should_exit = 0;
	int interactive = 1;
	int jobnum = 1;
	int c;
	FILE *fp = NULL;
	FILE *inbuffer = stdin;
	action_t action;
	int status;

	// turn off friggen buffering...it ruins our day!!
	setbuf(stdout, NULL);
	switch (argc) {
		case 1:
			break;
		case 2:
			fp = fopen(argv[1], "r");
			if (fp == NULL) {
				fprintf(stderr, "Error: unable to open file %s\n", argv[1]);
				return 1;
			}
			interactive = 0;
			inbuffer = fp;
			break;
		default:
			fprintf(stderr, "Invalid number of command line arguments: %i\n",
					(argc - 1));
			return 1;
	}
	shell_t *turtle_shell = create_shell();
	job_t *jobs[MAX_JOBS]; // we aren't freeing these...memory leak!!

	while(!should_exit) {
		jobs[jobnum - 1] = malloc(sizeof(job_t));
		if((jobs[jobnum - 1]) == NULL) {
			fprintf(stderr, "Unable to malloc() a job in main()!!\n");
			exit(1);
		}
		action = run_shell(turtle_shell, interactive, &jobnum, jobs[jobnum - 1],
						 inbuffer);
		switch (action) {
			case WAITERROR:
				fprintf(stderr, "Invalid jid\n");
				break;
			case EXITVAL:
				should_exit = 1;
				break;
			case JOBVAL:
				do_jobcmd(jobs, jobnum);
				break;
			case NORMAL:
				break; // nothing, just run our loop again
			case CHILDEXIT:
				exit(1);
			default:
				if (action < (jobnum))  
					do_waitcmd(jobs[action - 1]);
				
				else 
					printf("Invalid jid %d\n", action);
				
		}

		// reap our children here i guess.  we're doing a lot of dumb
		// algorithms in this program (with reaping and the "j" command and
		// such, but I'm sleepy and I haven't gotten any sleep in forever.
		// this bad algorithm reaps zombies every command
		for (c = 0 ; c < jobnum - 1 ; c++)
			waitpid(jobs[c]->pid, &status, WNOHANG);
	}
	if (argc > 1)
		fclose(fp);
	for (c = 0 ; c < jobnum - 1; c++) {
		remove_job(jobs[c]);
	}
	return 0;
}