#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../lib/util.h"

int process_slope(int slope[]) {
  InputWithSize *input_with_size = load_input_with_size();
  char *data_buffer = input_with_size->data_buffer;
  int input_size = input_with_size -> size;

  char *first_line = strtok(data_buffer, "\n");
  const int course_width = strlen(first_line) + 1; // Account for \n

  int position[2] = {0, 0};
  int index = (position[0] * course_width) + position[1];

  int trees_hit = 0;
  do {
    if (data_buffer[index] == '#') trees_hit++;
    position[0] += slope[0];
    position[1] += slope[1];
    position[1] %= (course_width - 1);
    index = (position[0] * course_width) + position[1];
  } while (index < input_size);

  free_input_with_size(input_with_size);
  return trees_hit;
}

int part_1() {
  int slope[2] = {1, 3};
  return process_slope(slope);
}

int part_2() {
  int slopes[5][2] = {
    1, 1,
    1, 3,
    1, 5,
    1, 7,
    2, 1
  };
  int product = 1;
  for (int i = 0; i < 5; i++) {
    product *= process_slope(slopes[i]);
  }
  return product;
}

int main() {
  printf("Part 1: %d\n", part_1());
  printf("Part 2: %d\n", part_2());
  return 0;
}