// SPDX-License-Identifier: BSD-3-Clause

#include <time.h>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>

const char start[10] = {'s','s','s','d','d','d','f','f','f','f'};
const char end[11] = {'g','g','g','h','h','h','j','k','l','l','l'};

int
main (int argc, char *argv[]) {
	if (argc <= 1) {
		puts("Give me the keymash length!");
		return 1;
	}
	int keymashlength = atoi(argv[1]);
	if (keymashlength <= 0) {
		puts("Bad length >:(");
		return 1;
	}
	char *keymash = malloc(keymashlength+1);
	int r,total = 0;
	char prev = 'a';
	int val = 0;
	int switchup = 0;

	srand(time(NULL));
	total += sprintf(keymash+total, "%c", prev);
	while (total < keymashlength) {
		if (val == 0) {
			int j = total+2 < keymashlength ? 2 : 1;
			for (int i = 0; i < j; i++) {
				r = abs((rand() % 10 - r) + r);
				if (prev != start[r]) {
					total += sprintf(keymash+total, "%c", start[r]);
					prev = start[r];
					//total += 1;
				} else {
					i -= 1;
				}
			}
			switchup = switchup < 0 ? 0 : switchup+1;
		} else if (val == 1) {
			int j = total+2 < keymashlength ? 2 : 1;
			for (int i = 0; i < j; i++) {
				r = abs((rand() % 11));
				if (prev != end[r]) {
					total += sprintf(keymash+total, "%c", end[r]);
					prev = end[r];
				} else {
					i -= 1;
				}
			}
			switchup = switchup > 0 ? 0 : switchup-1;
		}
		if (switchup < 2 || switchup > -2) {
			val = abs(rand() % 2);
		} else {
			val = switchup < 0 ? 0 : 1;
		}
	}
	puts(keymash);
	free(keymash);
	return 0;

}