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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#define COUNT 10
#define SIZE (10 * sizeof(int))
#define INP_COUNT 144
#define FLIP_X (0b11 << 0)
#define FLIP_Y (0b11 << 2)
#define ROT_ONE (0b11 << 4)
#define ROT_TWO (0b11 << 6)
#define ROT_THREE (0b11 << 8)
enum cnt_pos { T, R, B, L };
struct tile {
int id;
int match[INP_COUNT];
int reversed; // Bitmap
char image[COUNT][COUNT];
int cnt[4]; // cnt_pos
int top[COUNT];
int right[COUNT];
int bottom[COUNT];
int left[COUNT];
int top_rev[COUNT];
int right_rev[COUNT];
int bottom_rev[COUNT];
int left_rev[COUNT];
};
void set_rotation(int *reversed, int pos_a, int pos_b, int is_rev)
{
int rot = abs((pos_a + 1) - (pos_b + 1));
if (rot == 0)
return;
if (rot == 1 && !is_rev)
*reversed |= ROT_ONE;
else if (rot == 2 && !is_rev)
*reversed |= ROT_TWO;
else if (rot == 3 && !is_rev)
*reversed |= ROT_THREE;
if (is_rev && rot % 2 == 0) {
*reversed |= FLIP_X;
} else if (is_rev && rot % 2 == 1) {
*reversed |= FLIP_Y;
}
}
void reverse(int dest[], int src[])
{
for (int i = 0; i < COUNT; i++) {
dest[COUNT - 1 - i] = src[i];
}
}
long part_one(FILE *fp)
{
long res = 1;
struct tile tiles[INP_COUNT] = { 0 };
int tile_cnt = 0;
char *line = NULL;
size_t len;
int y = 0;
while (getline(&line, &len, fp) != -1) {
int num;
if (line[0] == '\n') {
tile_cnt++;
} else if (sscanf(line, "Tile %d:", &num) == 1) {
struct tile new = { 0 };
new.id = num;
tiles[tile_cnt] = new;
y = 0;
} else {
struct tile *tile = &tiles[tile_cnt];
memcpy(tile->image, line, COUNT);
if (y == 0) {
for (int i = 0; i < COUNT; i++) {
tile->top[i] = line[i] == '#';
tile->cnt[T] += tile->top[i];
}
} else if (y == COUNT - 1) {
for (int i = 0; i < COUNT; i++) {
tile->bottom[i] = line[i] == '#';
tile->cnt[B] += tile->bottom[i];
}
}
tile->left[y] = line[0] == '#';
tile->cnt[L] += tile->left[y];
tile->right[y] = line[COUNT - 1] == '#';
tile->cnt[R] += tile->right[y];
y++;
}
}
tile_cnt++;
free(line);
for (int i = 0; i < tile_cnt; i++) {
struct tile *tile = &tiles[i];
reverse(tile->top_rev, tile->top);
reverse(tile->right_rev, tile->right);
reverse(tile->bottom_rev, tile->bottom);
reverse(tile->left_rev, tile->left);
}
for (int i = 0; i < tile_cnt; i++) {
struct tile *tile = &tiles[i];
// Find adjacent
int *cur, cnt;
for (int j = 0; j < 4; j++) { // TRBL
switch (j) {
case T:
cnt = tile->cnt[T];
cur = tile->top;
break;
case R:
cnt = tile->cnt[R];
cur = tile->right;
break;
case B:
cnt = tile->cnt[B];
cur = tile->bottom;
break;
case L:
cnt = tile->cnt[L];
cur = tile->left;
break;
default:
exit(1);
break;
}
for (int k = 0; k < tile_cnt; k++) {
struct tile *cmp = &tiles[k];
if (cmp->id == tile->id)
continue;
int match_cnt = 0, reversed = 0;
if (cnt == cmp->cnt[T]) {
if (!memcmp(cur, cmp->top, SIZE)) {
set_rotation(&reversed, T, j, 0);
match_cnt++;
} else if (!memcmp(cur, cmp->top_rev, SIZE)) {
set_rotation(&reversed, T, j, 1);
match_cnt++;
}
}
if (cnt == cmp->cnt[R]) {
if (!memcmp(cur, cmp->right, SIZE)) {
set_rotation(&reversed, R, j, 0);
match_cnt++;
} else if (!memcmp(cur, cmp->right_rev, SIZE)) {
set_rotation(&reversed, R, j, 1);
//reversed |= REV_RIGHT;
match_cnt++;
}
}
if (cnt == cmp->cnt[B]) {
if (!memcmp(cur, cmp->bottom, SIZE)) {
set_rotation(&reversed, B, j, 0);
match_cnt++;
} else if (!memcmp(cur, cmp->bottom_rev, SIZE)) {
set_rotation(&reversed, B, j, 1);
//reversed |= REV_BOTTOM;
match_cnt++;
}
}
if (cnt == cmp->cnt[L]) {
if (!memcmp(cur, cmp->left, SIZE)) {
set_rotation(&reversed, L, j, 0);
match_cnt++;
} else if (!memcmp(cur, cmp->left_rev, SIZE)) {
set_rotation(&reversed, L, j, 1);
//reversed |= REV_LEFT;
match_cnt++;
}
}
tile->match[k] += match_cnt;
if (reversed != 0)
cmp->reversed = reversed;
}
}
}
for (int i = 0; i < tile_cnt; i++) {
struct tile *tile = &tiles[i];
if (tile->reversed)
printf("%d: %x\n", tile->id, tile->reversed);
int cnt = 0, flipped = 0;
for (int j = 0; j < tile_cnt; j++) {
cnt += tile->match[j];
}
if (cnt == 2) {
res *= tile->id;
}
}
return res;
}
long part_two(FILE *fp)
{
long res = 0;
return res;
}
int main(int argc, char *argv[])
{
FILE *fp = fopen("input", "r");
if (!fp)
exit(EXIT_FAILURE);
clock_t tic = clock();
printf("%lu\n", part_one(fp));
rewind(fp);
printf("%lu\n", part_two(fp));
clock_t toc = clock();
printf("TIME: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC);
fclose(fp);
return 0;
}
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