module CloudText

# File lib/cloud_text.rb, line 8
def self.clean_text(input, options = {})
  @input = input
  @options = options

  # Get feature on/off switches
  remove_digits = @options.fetch(:remove_digits, false)
  stemming_enabled = @options.fetch(:stemming, false)

  # Get variables
  @language = @options.fetch(:language, "en")
  @custom_stopwords = @options.fetch(:stopwords, [])

  @input = process_text(@input, stemming_enabled, remove_digits, @language, @custom_stopwords)
  count_words(@input)
end

# File lib/cloud_text.rb, line 66
def self.count_words(input)
  input.each_with_object(Hash.new(0)) { |token, hash| hash[token] += 1 }.sort_by(&:last).reverse
end

# File lib/cloud_text.rb, line 49
def self.filter_stopwords(input, language, custom_stopwords = nil)
  stopword_filter = language == "tr" ? Stopwords::Filter.new(tr_stopwords) : stopword_filter = Stopwords::Snowball::Filter.new(language)

  # Here we intentionally do not downcase custom_stopwords
  # since we want to filter only capitalized version of a word
  stopword_filter.stopwords << custom_stopwords if custom_stopwords
  stopword_filter.filter(input.split)
end

# File lib/cloud_text.rb, line 44
def self.lowercase_words(input, language)
  UnicodeUtils.downcase(input, language.to_sym)
end

# File lib/cloud_text.rb, line 26
def self.process_text(input, stemming_enabled, remove_digits, language, custom_stopwords)
  input = remove_punctuation(input, remove_digits)
  input = reduce_whitespaces(input)
  input = lowercase_words(input, language)
  input = filter_stopwords(input, language, custom_stopwords) # Get custom_stopwords from user and filter words
  input = stemming(input, language) if stemming_enabled
end

# File lib/cloud_text.rb, line 40
def self.reduce_whitespaces(input)
  input.gsub(/\s+/, ' ')
end

# File lib/cloud_text.rb, line 34
def self.remove_punctuation(input, remove_digits)
  regex = remove_digits ? /[^A-Za-z0-9^şŞıİçÇöÖüÜĞğ\s]|_|\d/ : /[^A-Za-z0-9^şŞıİçÇöÖüÜĞğ\s]|_/
  input.gsub(regex, ' ')
end

# File lib/cloud_text.rb, line 58
def self.stemming(input, language)
  stemmer = Lingua::Stemmer.new(language: language)
  input.map do |word|
    stemmer.stem(word)
  end
end

# File lib/cloud_text.rb, line 70
def self.tr_stopwords
  File.readlines('tr_stopwords_dict').each(&:chomp!)
end