#!/usr/bin/env ruby
# frozen_string_literal: true

require 'pry'

def diagonal(array, x, y)
  x_limit = array.size - 1 - x
  y_limit = array[0].size - 1 - y
  limit = x_limit < y_limit ? x_limit : y_limit
  (0..limit).map { |i| array[x + i][y + i] }
end

def diagonal2(array, x, y)
  x_limit = array.size - 1 - x
  y_limit = y
  limit = x_limit < y_limit ? x_limit : y_limit
  (0..limit).map { |i| array[x + i][y - i] }
end

def xmas_slice(array, x, y)
  out = []
  out.append(array[x][y] + array[x + 1][y + 1] + array[x + 2][y + 2])
  out.append(array[x][y + 2] + array[x + 1][y + 1] + array[x + 2][y])
  (out[0].match?(/MAS|SAM/) and out[1].match?(/MAS|SAM/))
end

# input = 'MMMSXXMASM
# MSAMXMSMSA
# AMXSXMAAMM
# MSAMASMSMX
# XMASAMXAMM
# XXAMMXXAMA
# SMSMSASXSS
# SAXAMASAAA
# MAMMMXMMMM
# MXMXAXMASX'.split

input = File.readlines('./input').map(&:strip)

vertical = input.map(&:chars).transpose.map(&:join)
d1_coords = (0..(input.size - 1)).map { [0, _1] }
d2_coords = d1_coords.dup
d1_coords += (1..(input.size - 1)).map { [_1, 0] }
d2_coords += (1..(input.size - 1)).map { [_1, (input.size - 1)] }
diagonal = d1_coords.map { |x, y| diagonal(input, x, y) }.map(&:join)
diagonal2 = d2_coords.map { |x, y| diagonal2(input, x, y) }.map(&:join)
# binding.pry

count = 0
count += input.map { |line| line.scan('XMAS') }.flatten.length
count += input.map { |line| line.scan('SAMX') }.flatten.length
count += vertical.map { |line| line.scan('XMAS') }.flatten.length
count += vertical.map { |line| line.scan('SAMX') }.flatten.length
count += diagonal.map { |line| line.scan('XMAS') }.flatten.length
count += diagonal.map { |line| line.scan('SAMX') }.flatten.length
count += diagonal2.map { |line| line.scan('XMAS') }.flatten.length
count += diagonal2.map { |line| line.scan('SAMX') }.flatten.length

# binding.pry
puts count

# Part 2
p2 = (0..input.size - 3).map { |x| (0..input.size - 3).map { |y| xmas_slice(input, x, y) } }.flatten.count(true)

puts p2