publiclab/plots2

class Spamaway
  include ActiveModel::Model

  # This helper will generate pairs of human/robot statements and return
  # them alongside random strings.
  # There is no actual data in the database.
  def self.columns
    @columns ||= []
end

  def self.column(name, sql_type = nil, default = nil, null = true)
    columns << ActiveRecord::ConnectionAdapters::Column.new(name.to_s, default, sql_type.to_s, null)
  end

  column :follow_instructions, :string
  column :statement1, :string
  column :statement2, :string
  column :statement3, :string
  column :statement4, :string

  attr_accessor :follow_instructions, :statement1, :statement2, :statement3, :statement4

  validate :clean_honeypot, :human_responses

  def self.get_pairs(how_many)
    @human = [I18n.t('spamaway.human.statement1'),
              I18n.t('spamaway.human.statement2'),
              I18n.t('spamaway.human.statement3'),
              I18n.t('spamaway.human.statement4'),
              I18n.t('spamaway.human.statement5'),
              I18n.t('spamaway.human.statement6')]

    @robot = [I18n.t('spamaway.robot.statement1'),
              I18n.t('spamaway.robot.statement2'),
              I18n.t('spamaway.robot.statement3'),
              I18n.t('spamaway.robot.statement4'),
              I18n.t('spamaway.robot.statement5'),
              I18n.t('spamaway.robot.statement6')]

    # static method to return how_many pairs of human/robot statements.
    if (how_many <= 0) || (how_many > @human.length) || (how_many > @robot.length)
      raise ArgumentError, 'Cannot return ' + how_many + ' statements.'
    end

    # randomly select how_many statements from each list
    human_perms = @human.permutation(how_many).to_a
    robot_perms = @robot.permutation(how_many).to_a
    human_index = rand(human_perms.length)
    robot_index = rand(robot_perms.length)

    # slap pairs together
    pairs = human_perms[human_index].zip(robot_perms[robot_index])
    # randomly flip human/robot order for each statement pair
    pairs.each_index do |i|
      pairs[i] = pairs[i].permutation.to_a[rand * 2]
    end
    pairs
  end

  def human_response?(response)
    @human = [I18n.t('spamaway.human.statement1'),
              I18n.t('spamaway.human.statement2'),
              I18n.t('spamaway.human.statement3'),
              I18n.t('spamaway.human.statement4'),
              I18n.t('spamaway.human.statement5'),
              I18n.t('spamaway.human.statement6')]

    @robot = [I18n.t('spamaway.robot.statement1'),
              I18n.t('spamaway.robot.statement2'),
              I18n.t('spamaway.robot.statement3'),
              I18n.t('spamaway.robot.statement4'),
              I18n.t('spamaway.robot.statement5'),
              I18n.t('spamaway.robot.statement6')]

    # return True if response is a human response, False otherwise.
    @human.member? response
  end

  private

  def clean_honeypot
    # errors if the honeypot (follow_instructions) is not clean.
    unless follow_instructions.blank? || (follow_instructions == '')
      errors.add(:base, I18n.t('spamaway.errors.please_read_instructions'))
    end
  end

  def human_responses
    # confirms all statements are human responses.
    statements = [statement1, statement2, statement3, statement4]
    # turn statements into T/F array and keep only the Trues
    not_robot = statements.map { |a| human_response? a } .select { |a| a }
    # make sure the number of Trues matches the number of original statements
    if statements.length != not_robot.length
      errors.add(:base, I18n.t('spamaway.errors.not_a_real_person'))
    end
  end
end