#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>

#include "stlfile.h"

#define ARRSIZE(x) (sizeof(x)/sizeof((x)[0]))

struct command {
	const char *name;
	void (*func)();
};

void request_info();
void parse_file();
void cat_flag();
void list_commands();

struct command commands[] = {
	{ "request", request_info },
	{ "info", parse_file },
	{ "cat", cat_flag },
	{ "ls", list_commands },
};

const char*
ask(const char *fmtstr, ...)
{
	static char linebuf[256];
	va_list ap;

	va_start(ap, fmtstr);
	vprintf(fmtstr, ap);
	va_end(ap);

	fgets(linebuf, sizeof(linebuf), stdin);

	return linebuf;
}

void*
die(const char *fmtstr, ...)
{
	va_list ap;

	va_start(ap, fmtstr);
	vfprintf(stderr, fmtstr, ap);
	va_end(ap);

	exit(EXIT_FAILURE);
}

void
request_info()
{
	const char *bufp;
	char *end, *contents;
	int len;

	bufp = ask("How large is your file?\n");
	len = strtoul(bufp, &end, 10);
	if (!len || *end || len < 7000)
		die("Invalid file length!\n");

	printf("Ok! Im listening..\n");
	contents = malloc(len);
	read(STDIN_FILENO, contents, len);

	printf("I got: %s\n", contents);

	free(contents);
}

void
parse_file()
{
	printf("hi\n");
}

void
cat_flag()
{
	FILE *f;
	char catbuf[256];
	int nb;

	f = fopen("cat", "r");
	nb = fread(catbuf, 1, sizeof(catbuf), f);
	fclose(f);

	printf("%.*s\n", nb, catbuf);
}

void
list_commands()
{
	int i;

	printf("Available commands:\n");
	for (i = 0; i < ARRSIZE(commands); i++)
		printf("%s%s", i ? " " : "", commands[i].name);
	printf("\n");
}

int
main()
{
	char linebuf[256], *cp;
	int exit, i;

	exit = 0;
	while (!exit) {
		memset(linebuf, ' ', sizeof(linebuf));

		printf("$ ");
		exit = !fgets(linebuf, sizeof(linebuf), stdin);
		if (exit || !*linebuf) break;

		if (*linebuf == '\n') continue;
		linebuf[strlen(linebuf) - 1] = '\0';

		cp = strchr(linebuf, ' ');
		if (cp) *cp = 0;
		for (i = 0; i < ARRSIZE(commands); i++) {
			if (!strcmp(commands[i].name, linebuf)) {
				commands[i].func();
				break;
			}
		}
	}

	printf("see you later!\n");
}