Jack of all trades, master of some…

# UserChallenge provides several mechanisms to aid in establishing a real user is on the end of a submit
 
# Typically used for user registration processes or commenting, the UserChallenge module will allow you to provide
 
# a challenge question and validate the repsponse.
 
# Mixins include
 
#       * SumChallenge - provides a simple arimethetic sum to be solved
 
#       * RandomTextChallenge - supplies a random string of characters
 
# Supporting Classes include
#       * SumTextChallenger - Class that will provide a question as a text string
#       * SumImageChallenger - Class that will create a png image with the sum in it
#       * RandomTextChallenger - Class that will provide a random text string
#       * RandomTextImageChallenger - Class that will create a png image with the random text string in it
 
module UserChallenge
 
 # This module creates a challenge that is a basic sum, expecting the respose to be the sums result, e.g. 2+6
 module SumChallenge
 #Initailizes the challenge to a sum
 #optionally specify the max values for the left and right 
 def createChallenge(lMax=10, rMax=10)
 	lValue = rand(lMax)
 	rValue = rand(rMax)
 	@solution = lValue + rValue
 	@question = "#{lValue} + #{rValue}"
 end
 
 # checks the value passed in against the expected result 
 def checkResponse(value)
 	return (@solution == value.to_i)
 end
end
 
 # This module creates a challenge that is a series of random characters in a specified range, expecting the respose to be the same string module RandomTextChallenge
 # Initailizes the challenge to a sum
 # optionally specify the number of characters to generate and the range of characters to choose from 
 def createChallenge(count=6, chars = 'a'..'z')
 	@question = ""
	count.times do
		index = rand(chars.entries.length-1)
		@question += chars.entries[index]
 	end
 	@solution = @question
 end
 
 # checks the value passed in against the expected result 
 def checkResponse(value)
	 return (@solution == value.to_s)
	 end
 end
 
 # A simple class that generates a sum challenge in text form
 class SumTextChallenger
	 include SumChallenge
 
	 # the sum question as a string
	 attr_reader :question
	 # the solution as an integer
	 attr_reader :solution
 
	 def initialize()
		 createChallenge()
	 end
 end
 
 # A class that generates a sum challenge in image form
 class SumImageChallenger
 	require "RMagick"
	include SumChallenge
 
 	# the sum question as a string
	attr_reader :question
 	# the solution as an integer
 	attr_reader :solution
 
 	def initialize()
		createChallenge()
 	end
 
 # returns an image blob with the sum question layered ontop of the specified background
 def render(backgroundImageUrl)
 	background = Magick::Image.read(backgroundImageUrl).first
 
 	croppedImg = background.crop(0,0,128,28)
 
 	text = Magick::Draw.new
	text.annotate(croppedImg, 128, 28, 0, 0, @question) {
		self.gravity = Magick::SouthGravity
		self.pointsize = 24
		self.stroke = 'transparent'
		self.fill = '#0000A9'
		self.font_weight = Magick::BoldWeight
	}
 
 	croppedImg = croppedImg.blur_image
 	return croppedImg.to_blob
 	end
 end
 
 # A simple class that generates a random text challenge in text form
 class RandomTextChallenger
 include RandomTextChallenge
 
 # the sum question as a string
 attr_reader :question
 # the solution as an integer
 attr_reader :solution
 
 def initialize()
 	createChallenge()
 	end
 end
 
 # A class that generates a random text challenge in image form
 class RandomTextImageChallenger
 	require "RMagick"
 	include RandomTextChallenge
 
 	# the sum question as a string
	attr_reader :question
 	# the solution as an integer
 	attr_reader :solution
 
	def initialize()
 	createChallenge()
	end
 
 	# returns an image blob with the sum question layered ontop of the specified background
 	def render(backgroundImageUrl, width=128)
		background = Magick::Image.read(backgroundImageUrl).first
 
 		croppedImg = background.crop(0,0,width,28)
 
 		text = Magick::Draw.new
		text.annotate(croppedImg, width, 28, 0, 0, @question) {
		self.gravity = Magick::SouthGravity
		self.pointsize = 22
		self.stroke = 'transparent'
 		self.fill = '#0000A9'
 		self.font_weight = Magick::BoldWeight
 		}
 
 		croppedImg = croppedImg.blur_image
		return croppedImg.to_blob
	 	end
 	end
end

class MainController < ApplicationController  require "UserChallenge"
 
  def welcome
    @challenge = UserChallenge::UserSumImageChallenge.new
    session["uc"] = @challenge#
  end
 
  def image
    storePath = "/home/user/path"
    filename = storePath + "/Camouflage.png"
 
    challenge = session["uc"]
    session["uc"] = nil
    send_data challenge.render(filename), :filename => "confirm.png", :type => 'image/png', :disposition => 'inline'  
  end
 
end