require 'fastercsv'
namespace :test_api do

   task :all => [:question_vote_consistency]

   desc "Don't run unless you know what you are doing"
   task(:generate_lots_of_votes => :environment) do
      if Rails.env.production?
	 print "You probably don't want to run this in production as it will falsify a bunch of random votes"
      end
 
 
     current_user = User.first
      3000.times do 
	      question = Question.find(120) # test question change as needed
	      @p = Prompt.find(question.catchup_choose_prompt_id)

	      current_user.record_vote("test_vote", @p, rand(2))
      end

   end

   desc "Should only need to be run once"
   task(:generate_all_possible_prompts => :environment) do
      inserts = []
      Question.find(:all).each do |q|
	choices = q.choices
	if q.prompts.size > choices.size**2 - choices.size
		print "ERROR: #{q.id}\n"
		next
	elsif q.prompts.size == choices.size**2 - choices.size
		print "#{q.id} has enough prompts, skipping...\n"
		next
	else
		print "#{q.id} should add #{(choices.size ** 2 - choices.size) - q.prompts.size}\n"

	end
        timestring = Time.now.to_s(:db) #isn't rails awesome?
	promptscount=0
  	the_prompts = Prompt.find(:all, :select => 'id, left_choice_id, right_choice_id', :conditions => {:question_id => q.id})

	the_prompts_hash = {}
	the_prompts.each do |p|
		the_prompts_hash["#{p.left_choice_id},#{p.right_choice_id}"] = 1
	end

        choices.each do |l|
	   choices.each do |r|
	     if l.id == r.id
		   next
	     else
		#p = the_prompts.find{|o| o.left_choice_id == l.id && o.right_choice_id == r.id}
		keystring = "#{l.id},#{r.id}"
		p = the_prompts_hash[keystring]
		if p.nil?
	           print "."
	           inserts.push("(NULL, #{q.id}, NULL, #{l.id}, '#{timestring}', '#{timestring}', NULL, 0, #{r.id}, NULL, NULL)")
		   promptscount+=1
		end

	     end

	   end
         end

	print "Added #{promptscount} to #{q.id}\n"

       Question.update_counters(q.id, :prompts_count => promptscount)

       end

    sql = "INSERT INTO `prompts` (`algorithm_id`, `question_id`, `voter_id`, `left_choice_id`, `created_at`, `updated_at`, `tracking`, `votes_count`, `right_choice_id`, `active`, `randomkey`) VALUES #{inserts.join(', ')}"

    unless inserts.empty?
       ActiveRecord::Base.connection.execute(sql)
    end
   
   end


   desc "Dump votes of a question by left vs right id"
   task(:make_csv => :environment) do

	   q = Question.find(120)

	   the_prompts = q.prompts_hash_by_choice_ids

	   #hash_of_choice_ids_from_left_to_right_to_votes
	   the_hash = {}
	   the_prompts.each do |key, p|
		   left_id, right_id = key.split(", ")
		   if not the_hash.has_key?(left_id)
			   the_hash[left_id] = {}
			   the_hash[left_id][left_id] = 0
		   end

		   the_hash[left_id][right_id] = p.votes.size
	   end

	   the_hash.sort.each do |xval, row|
		   rowarray = []
		   row.sort.each do |yval, cell|
			   rowarray << cell
		   end
		   puts rowarray.join(", ")
	   end
   end


   desc "Generate density information for each question - should be run nightly"
   task(:generate_density_information => :environment) do
	   Question.find(:all).each do |q|
		   q.save_densities!
	   end
   end
      
   desc "Description here"
   task(:question_vote_consistency => :environment) do
      questions = Question.find(:all)

      error_msg = ""

      questions.each do |question|

	total_wins =0
	total_votes =0
	total_generated_prompts_on_left = 0
	total_generated_prompts_on_right = 0
	error_bool = false
	question.choices.each do |choice|
			
	    if choice.wins
	      total_wins += choice.wins
	      total_votes += choice.wins
	    end

	    if choice.losses
              total_votes += choice.losses
	    end

	    total_generated_prompts_on_left += choice.prompts_on_the_left.size
	    total_generated_prompts_on_right += choice.prompts_on_the_right.size
        end
	
	if (2*total_wins != total_votes)
		 error_msg += "Error 1: 2 x Total Wins != Total votes"
		 error_bool= true
	end

	if(total_votes % 2 != 0)
		error_msg += "Error 2: Total votes is not Even!"
		error_bool= true
	end

	if(total_votes != 2* question.votes_count)
		error_msg += "Error 3: Total votes != 2 x # vote objects"
		error_bool = true
	end

	if(total_generated_prompts_on_right != total_generated_prompts_on_right)
		error_msg += "Error 4: Total generated prompts on left != Total generated prompts on right"
		error_bool = true
	end

	wins_by_choice_id = question.votes.active.count(:group => :choice_id)
	losses_by_choice_id= question.votes.active.count(:conditions => "loser_choice_id IS NOT NULL", :group => :loser_choice_id)

	#Rails returns an ordered hash, which doesn't allow for blocks to change merging logic.
	#A little hack to create a normal hash
	wins_hash = {}
	wins_hash.merge!(wins_by_choice_id)
	losses_hash = {}
	losses_hash.merge!(losses_by_choice_id)


	appearances_by_choice_id = wins_hash.merge(losses_hash) do |key, oldval, newval| oldval + newval end

	sum = total_appearances = appearances_by_choice_id.values.inject(0) {|sum, x| sum +=x}
	mean = average_appearances = total_appearances.to_f / appearances_by_choice_id.size.to_f

	if sum > 0:
	   stddev = Math.sqrt( appearances_by_choice_id.values.inject(0) { |sum, e| sum + (e - mean) ** 2 } / appearances_by_choice_id.size.to_f )

           appearances_by_choice_id.each do |choice_id, n_i| 
		if (n_i < (mean - 6*stddev)) || (n_i > mean + 6 *stddev)
			error_msg += "Choice #{choice_id} in Question ##{question.id} has an irregular number of appearances: #{n_i}, as compared to the mean: #{mean} and stddev #{stddev} for this question"
			error_bool = true
		end
	   end
	end
			


	if error_bool
	   error_msg += "Question #{question.id}: 2*wins = #{2*total_wins}, total votes = #{total_votes}, vote_count = #{question.votes_count}\n"
	end
	error_bool = false
     end
     
     if error_msg.blank?
        
	success_msg = "Conducted the following tests on API data and found no inconsistencies.\n" +
			 "For each of the #{questions.length} questions in the database: \n" +
			 "     2 x Total Wins = Total Votes\n" +
			 "     Total Votes (wins + losses) is Even\n" +
			 "     Total Votes (wins + losses) = 2 x the number of vote objects that belong to the question\n" +
		         "     Total generated prompts on left = Total generated prompts on right\n" + 
		         "     Each choice has appeared n times, where n falls within 6 stddevs of the mean number of appearances for a question\n" +
			 "             Note: this applies only to seed choices (not user submitted) and choices currently marked active\n"

	print success_msg

	CronMailer.deliver_info_message(CRON_EMAIL, "Test of API Vote Consistency passed", success_msg)
     else
     	CronMailer.deliver_info_message("#{CRON_EMAIL},#{ERRORS_EMAIL}", "Error! Failure of API Vote Consistency " , error_msg)
     end

   end
end