ocr_v2

ocr.rb

require 'pry'

class OCR
  attr_reader :text

  def initialize(text)
    @text = text
  end

  def convert
    if single_digit?
      convert_single_digit(text)
    elsif multiple_digits_in_line?
      convert_line(text)
    elsif multiple_lines?
      convert_paragraph(text)
    end
  end

  private

  def single_digit?
    text.length <= 15
  end

  def multiple_digits_in_line?
    text.length > 15 && !text.include?("\n\n")
  end

  def multiple_lines?
    text.length > 15 && text.include?("\n\n")
  end

  def convert_single_digit(text)
    case text
    when " _\n| |\n|_|\n" then '0'
    when "\n  |\n  |\n"   then '1'
    when " _\n _|\n|_\n"  then '2'
    when " _\n _|\n _|\n" then '3'
    when "\n|_|\n  |\n"   then '4'
    when " _\n|_\n _|\n"  then '5'
    when " _\n|_\n|_|\n"  then '6'
    when " _\n  |\n  |\n" then '7'
    when " _\n|_|\n|_|\n" then '8'
    when " _\n|_|\n _|\n" then '9'
    when "\n" then ','
    else '?'
    end
  end

  def convert_line(line)
    result = ''
    parse_line(line).each do |digit|
      result << convert_single_digit(digit)
    end
    result
  end

  def parse_line(line)
    if line == "\n"
      [line]
    else
      rows = line.split("\n")
      rows.each_with_index { |row, index| rows[index] = row.scan(/.{1,3}/).map!(&:rstrip) }.flatten!
      num_count = rows.length / 3
      nums = []
      num_count.times { |num| nums << rows[num] + "\n" + rows[num_count + num] + "\n" + rows[num_count * 2 + num]  + "\n" }
      nums
    end
  end

  def convert_paragraph(para)
    result = ''
      parse_paragraphs(para).each do |line|
      result << convert_line(line)
      end
    result
  end

  def parse_paragraphs(para)
    para.gsub!(/\n\n/, "\n*\n*").split("*")
  end
end