module Framingham::Diabetes extend Framingham, self
include Framingham

def eval options = {}
  begin
    #initialize
    options = NORMAL.merge options
    @age = options[:age].to_f
    @blood_pressure = options[:blood_pressure].to_f
    @body_mass_index = options[:body_mass_index].to_f
    @diabetes_relative = options[:diabetes_relative].to_s.to_sym
    @fasting_glucose = options[:fasting_glucose].to_f
    @gender = options[:gender].to_sym
    @hdl = options[:hdl].to_f
    @triglyceride = options[:triglyceride].to_f
    #validate
    raise ERRORS[:gender] unless GENDERS.include? @gender
  rescue => exception
    abort "\033[31merror: " + exception.message + "\033[0m"
  else
    #calculate
=begin debug stuff
    puts options.to_s
    puts "50-65:               " + (50...65).include?(@age).to_s
    puts "65+:                 " + (@age >= 65).to_s
    puts "blood_pressure >130: " + (@blood_pressure > 130).to_s
    puts "bmi 25-30:           " + (25...30).include?(@body_mass_index).to_s
    puts "bmi >=30:            " + (@body_mass_index >= 30).to_s
    puts "diabetes_relative:   " + @diabetes_relative.eql?(:true).to_s
    puts "fasting_glucose:     " + (100..126).include?(@fasting_glucose).to_s
    puts "gender:              " + @gender.to_s
    puts "hdl:                 " + (@gender.eql?(:female) and @hdl < 50 or @hdl < 40).to_s
    puts "triglyceride >= 150: " + (@triglyceride >= 150).to_s
=end
    risk_factor = BETA_ZERO[@gender]
    risk_factor += 0.018 if (50...65).include? @age
    risk_factor += 0.081 if @age >= 65
    risk_factor -= 0.565 if @diabetes_relative.eql? :true
    risk_factor -= 0.301 if (25...30).include? @body_mass_index
    risk_factor -= 0.920 if @body_mass_index >= 30
    risk_factor -= 0.498 if @blood_pressure > 130
    risk_factor -= 0.944 if @gender.eql? :female and @hdl < 50 or @hdl < 40
    risk_factor -= 0.575 if @triglyceride >= 150
    risk_factor -= 1.980 if (100..126).include? @fasting_glucose
    1 / (1 + Math.exp(risk_factor))
  end
end

def help
  "Evaluate 8 year diabetes risk"
end

protected

NORMAL = { #default options
  age:                      30,
  blood_pressure:           125,
  body_mass_index:          22.5,
  diabetes_relative:        false,
  fasting_glucose:          85,
  gender:                  :female,
  hdl:                      60,
  triglyceride:             130
} unless defined? NORMAL

ERRORS = {
  gender: "invalid gender, options: " + GENDERS.join
} unless defined? ERRORS

BETA_ZERO = {
  male:   5.517 + 0.010,
  female: 5.517
}

end