#!/usr/bin/env ruby

@letters = {} 
data = File.read("data.txt")
data = data.split("\n")
data = data.map(&:chars)
data.each_with_index do |row, y|
  row.each_with_index do |letter, x|
    @letters[[x,y]] = letter
  end
end
PREFIX = "X"
SUFIX = %w(M A S)

found = 0

def find_with_vector(start_x, start_y, x, y)
 word = (1..3).map do |iter|

  @letters[[start_x + (iter * x), start_y + (iter * y)]]
 end

 true if word.to_a == SUFIX
end

potential_starts = @letters.select{|key, val| val == PREFIX } 
potential_starts.each do |key, value| 

    found+= 1 if find_with_vector(key[0], key[1], 0, 1)
    found+= 1 if find_with_vector(key[0], key[1], 1, 0)

    found+= 1 if find_with_vector(key[0], key[1], 0, -1)
    found+= 1 if find_with_vector(key[0], key[1], -1, 0)

    found+= 1 if find_with_vector(key[0], key[1], 1, 1)
    found+= 1 if find_with_vector(key[0], key[1], -1, 1)
    found+= 1 if find_with_vector(key[0], key[1], 1, -1)
    found+= 1 if find_with_vector(key[0], key[1], -1, -1)
end

p found



exit

def find_with_vector(start_y, start_x, y, x)
  word = (1..3).map do |offset|
    tested_row = @data[ start_x + offset* x ]
    return false unless tested_row

    letter = tested_row[ start_y + offset * y ]
    return unless SUFIX.include? letter

    letter
  end
  
  p [word, start_x, start_y, x, y] if word == SUFIX
  true if word == SUFIX


end

found_count = 0
@data.each_with_index do |row, y|
  row.each_with_index do |letter, x|
    next unless letter == "X"
    
    found_count += 1 if find_with_vector(x,y, 0, 1)
    found_count += 1 if find_with_vector(x,y, 1, 0)

    found_count += 1 if find_with_vector(x,y, 0, -1)
    found_count += 1 if find_with_vector(x,y, -1, 0)

    found_count += 1 if find_with_vector(x,y, 1, 1)
    found_count += 1 if find_with_vector(x,y, -1, 1)
    found_count += 1 if find_with_vector(x,y, 1, -1)
    found_count += 1 if find_with_vector(x,y, -1, -1)


  end
end

p found_count