flippy.c (update 2016-04-07)

/* flippy.c
 * I wrote this quickie because a specific puzzle in Minecraft is extremely difficult.
 * Specifically, the second puzzle in the puzzle branch of a map called "Diversity".
 * The program emulates the puzzle's core logic and prints your solution if you happen to solve it. I have not solved it :V
 *
 * [Update 2016-04-07] I updated the code to be more windows-friendly.
 *   + Added a compiler flag so the user doesn't have to bang around in code they don't understand
 *   * For non-ANSI mode, I replaced "[ ON  ]" and "[ OFF ]" with a more visually obvious "[ +++ ]" and "[     ]"
 */

#include <stdio.h>
#include <stdlib.h>

/* Note: this code uses linux-specific terminal features in get_choice() and slot_read_color().
 * If you're on Windows, add -DNOFANCY to your compile line to disable USE_ANSI and USE_STTY.
 */

#if defined(NOFANCY)
#    define USE_ANSI 0
#    define USE_STTY 0
#else
#    define USE_ANSI 1
#    define USE_STTY 1
#endif

typedef enum SlotMasks {
    sm_1,
    sm_2,
    sm_3,
    sm_4,
    sm_5,
    sm_6,
    sm_7,
} SlotMask;

void slot_toggle(int *slots, SlotMask sm);
int slot_read(int *slots, SlotMask sm);
char *slot_read_color(int *slots, SlotMask sm);
void print_slots(int *slots);
void print_choices();
void print_past_choices(int *pastChoices);
void exec_choice(int *slots, int choice);
int get_choice();
int getnum();
void game_loop();

void
slot_toggle(int *slots, SlotMask sm)
{/*{{{*/
    *slots ^= (1 << sm);
}/*}}}*/

int
slot_read(int *slots, SlotMask sm)
{/*{{{*/
    return !!((*slots) & (1 << sm));
}/*}}}*/

char *
slot_read_color(int *slots, SlotMask sm)
{/*{{{*/
    if(slot_read(slots, sm) == 1){
        return USE_ANSI ? "\e[0;32m ON  \e[0m" : " +++ ";
    } else {
        return USE_ANSI ? "\e[0;31m OFF \e[0m" : "     ";
    }
}/*}}}*/

void
print_slots(int *slots)
{/*{{{*/
    SlotMask sm = sm_1;

    printf("\n");

    while(sm <= sm_7){
        printf("   %i    ", sm + 1);
        sm++;
    }

    printf("\n");
    sm = sm_1;

    while(sm <= sm_7){
        printf("[%s] ", slot_read_color(slots, sm));
        sm++;
    }

    printf("\n");
}/*}}}*/

void
print_choices()
{/*{{{*/
    printf("Select flipper:\n");
    printf("  1: 1, 4, 7\n");
    printf("  2: 1, 2, 6\n");
    printf("  3: 3, 5, 6\n");
    printf("  4: 2, 4, 7\n");
}/*}}}*/

int
getnum()
{/*{{{*/
    int num = fgetc(stdin) - '0';

    if(num >= 0 && num <= 9)
        return num;

    if(num == '\n' - '0')
        return -1;

    return -1;
}/*}}}*/

int
get_choice()
{/*{{{*/
    int c = -1;

    while(1){
        printf("\n>> ");
        if(USE_STTY)
            system("stty raw");

        c = getnum();

        if(USE_STTY)
            system("stty sane");

        if(c >= 1 && c <= 4){
            return c;
        } else if (c == -1){
            continue;
        } else {
            printf("E: Please enter a number between 1 and 4\n");
        }
    }
}/*}}}*/

void
exec_choice(int *slots, int choice)
{/*{{{*/
    switch(choice){
        case 1:
            slot_toggle(slots, sm_1);
            slot_toggle(slots, sm_4);
            slot_toggle(slots, sm_7);
            break;
        case 2:
            slot_toggle(slots, sm_1);
            slot_toggle(slots, sm_2);
            slot_toggle(slots, sm_6);
            break;
        case 3:
            slot_toggle(slots, sm_3);
            slot_toggle(slots, sm_5);
            slot_toggle(slots, sm_6);
            break;
        case 4:
            slot_toggle(slots, sm_2);
            slot_toggle(slots, sm_4);
            slot_toggle(slots, sm_7);
            break;
    }
}/*}}}*/

void
print_past_choices(int *pastChoices)
{/*{{{*/
    while(*pastChoices){
        printf("%i, ", *pastChoices);
        pastChoices++;
    }

    printf("\n");
}/*}}}*/

void
game_loop()
{/*{{{*/
    int slots = 0;
    int choice = 0;
    int pastChoices[51] = {0};
    int pci = 0;

    while(1){
        print_slots(&slots);
        print_choices();
        choice = get_choice();
        pastChoices[pci++] = choice;
        exec_choice(&slots, choice);

        if(slots == 127){
            break;
        }

        if(pci >= 50){
            printf("Solution exceeded 50 moves.\n");
            exit(1);
        }
    }

    printf("You win!\n");
    printf("Here are the choices that led to your victory:\n");
    print_past_choices(pastChoices);
}/*}}}*/

int
main()
{/*{{{*/
    game_loop();
}/*}}}*/