ocr.rb

require "csv"
require "base64"
require "typhoeus" # HTTP toolkit that is backed by CuRL
require "pry"  # debugger
require "json" # JSON parser that comes with standard Ruby library
require "oj" # JSON parser but uses C extensions

keywords = []

# {
#   "Chapter Number" => 1,
#   "Chapter Title" => "Basic Theory",
#   "Section Number" -> 1.1,
#   "Section Title" => "Basic Theory",
#   "Topic" => "Discrete mathematics",
#   "Importance Rating" => 3, # scale of 1-3 where 3 is most important
#   "Keyword count",
#   "Keyword" => [keyword]
# }

headers = [
  "Chapter Number",
  "Chapter Title",
  "Section Title",
  "Section Number",
  "Topic",
  "Importance Rating",
  "Keyword count",
  "Keywords"
]

GOOGLE_VISION = "https://vision.googleapis.com/v1/images:annotate"
API_KEY       = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"

# Get all the images that I took of the section keywords
images = Dir.
  children("images").
  map { |image| File.join(File.expand_path(File.dirname(__FILE__)), "images", image)  }.
  reject { |file| /DS_Store/.match?(file) }

# Go through each image and run Google's OCR through it
images.each do |image|
  
  # Prepare a POST body payload to send to Google
  payload = {
    "requests" => [{
      "image" => {
        "content" => Base64.encode64(File.read(image))
      },
      "features" => {
        "type" => "TEXT_DETECTION"
      }
    }]
  }	
  
  # Send request and transform it to a Ruby Hash/Map  
  response = Typhoeus.post(
    "#{GOOGLE_VISION}?fields=responses%2FfullTextAnnotation%2Ftext&key=#{API_KEY}", 
    body: JSON.dump(payload),
    headers: { "Content-Type" => "application/json"}
  ).body.yield_self { |body| Oj.load(body) }

  # Pull out results
  text = response.dig("responses", 0, "fullTextAnnotation", "text")

  if text
    # Clean up output so its more manageable
    words = text.split("\n").map { |keyword| keyword.gsub(/[^A-Za-z()\s]/, "").strip.capitalize }

    binding.pry
  end

  binding.pry
end


File.write("keywords.json", JSON.pretty_generate(keywords))