google_spellchecker.rb

# Queries the Google spellcheck API to allow for determining misspelled words
# as well as providing corrective suggestions.
#
# Largely taken from the TinyMCE PHP Spellchecker plugin
module GoogleSpellchecker
  require 'net/https'
  require 'uri'
  require 'builder'

  def check_spelling(spell_check_text, lang='en')
    matches = get_matches spell_check_text, lang
    words = []
    matches.each do |match|
      words << spell_check_text[match[0].to_i, match[1].to_i]
    end
    words
  end

  def get_spelling_suggestions(word, lang='en')
    matches = get_matches word, lang
    if matches.length > 0
      matches[0][3].split(/\s/).delete_if {|s| s.blank? }
    else
      []
    end
  end

  private
  def get_matches(str, lang)
    xml = Builder::XmlMarkup.new
    xml.instruct!
    xml.spellrequest(:textalreadyclipped => 0, :ignoredups => 0, :ignoredigits => 0, :ignoreallcaps => 1) do
      xml.text str
    end

    http = Net::HTTP.new("www.google.com", 443)
    http.use_ssl = true
    http.start do |req|
      @response = req.post("/tbproxy/spell?lang=#{lang}&hl=en", xml.target!)
    end

    if @response.code.to_i < 400
      @response.body.scan %r{<c o="(.*?)" l="(.*?)" s="(.*?)">(.*?)</c>}
    else
      []
    end
  end
end