#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "shuffle.h"

static int
rndrange(int max_excluding)
{
	assert(max_excluding > 0 && max_excluding < RAND_MAX);
	return rand() % max_excluding;
}

int
main()
{
	Shuffle s;
	char c[64], *p, *argv[4];
	int argc, i;
	int first, total, index, count;

	printf("> init TOTAL [FIRST]\n");
	printf("> resize TOTAL\n");
	printf("> get [INDEX] [COUNT]\n");
	total = 0;

	for(;;){
		c[sizeof(c)-1] = 0;
		printf("> ");
		if(fgets(c, sizeof(c), stdin) == NULL)
			break;
		if(c[sizeof(c)-1] != 0 || c[0] < 'a' || c[0] > 'z')
			continue;

		c[strlen(c)-1] = 0;
		argv[0] = p = c;
		for(argc = 1; argc < 4; argv[argc++] = p){
			if((p = strchr(p, ' ')) == NULL)
				break;
			for(*p++ = 0; *p == ' '; p++);
		}

		if(strcmp(argv[0], "init") == 0 && argc >= 2 && argc <= 3){
			if((total = atoi(argv[1])) < 1 || total >= RAND_MAX)
				printf("total is out of range [%d, %d]\n", 1, RAND_MAX-1);
			else{
				first = argc > 2 ? atoi(argv[2]) : rndrange(total);
				shuffle_init(&s, rndrange, total, first);
			}
		}else if(strcmp(argv[0], "resize") == 0 && argc == 2){
			total = atoi(argv[1]);
			shuffle_resize(&s, total);
		}else if(strcmp(argv[0], "get") == 0 && argc >= 1 && argc <= 3){
			index = argc > 1 ? atoi(argv[1]) : 0;
			count = argc == 2 ? 1 : (argc == 3 ? atoi(argv[2]) : total);
			for(i = index; i < index+count; i++)
				printf("%d ", shuffle_one(&s, i));
			printf("\n");
		}else{
			printf("?\n");
		}
	}

	return 0;
}