projects.mako.cc - selectricity/blob - app/models/election.rb

   1 class Election < ActiveRecord::Base
   2   has_many :candidates
   3   has_many :voters
   4   has_many :votes
   5   belongs_to :user
   6   validates_presence_of :name, :description
   7
   8   #validate that method is one of the listed election types
   9
  10   attr_reader :plurality_result
  11   attr_reader :approval_result
  12   attr_reader :condorcet_result
  13   attr_reader :ssd_result
  14   attr_reader :borda_result
  15
  16   require 'date'
  17
  18   def initialize(params={})
  19     super
  20     self.enddate = read_attribute( :enddate ) || \
  21                    Time.now + 30.days - 1.second
  22   end
  23
  24   def other_methods
  25     if election_method
  26       @other_methods = ELECTION_TYPES.keys.reject {|i| i == election_method}
  27     else
  28       @other_methods = nil
  29     end
  30     @other_methods
  31   end
  32
  33   def startdate
  34     read_attribute( :startdate ) || Time.now
  35   end
  36
  37   def votes
  38     votes = Array.new
  39     self.voters.each do |voter|
  40       votes << voter.vote
  41     end
  42     return votes
  43   end
  44
  45   def destroy
  46     self.candidates.each do |candidate|
  47       candidate.destroy
  48     end
  49     super
  50   end
  51
  52   def start_blockers
  53     reasons = []
  54     if self.candidates.length <= 1
  55       reasons << "You must have at least two candidates."
  56     end
  57
  58     if self.voters.length <= 1
  59       reasons << "You must have at least two voters."
  60     end
  61
  62     reasons
  63   end
  64
  65   def activate!
  66     self.active = 1
  67     self.save!
  68   end
  69
  70   def quickvote?
  71     self.class == 'QuickVote'
  72   end
  73
  74   def active?
  75     active == 1
  76   end
  77
  78   def done?
  79     active == 2
  80   end
  81
  82   def shortdesc
  83     shortdesc = description.split(/\n/)[0]
  84   end
  85
  86   def longdesc
  87     longdesc = description.split(/\n/)[1..-1].join("")
  88     longdesc.length > 0 ? longdesc : nil
  89   end
  90
  91   #Calculate Election Results
  92   def results
  93     # initalize the tallies to empty arrays
  94     preference_tally = Array.new
  95     plurality_tally = Array.new
  96     approval_tally = Array.new
  97
  98     self.voters.each do |voter|
  99       # skip if the voter has not voted or has an unconfirmed vote
 100       next unless voter.voted?
 101
 102       plurality_tally << voter.vote.rankings.sort[0].candidate.id
 103       approval_tally << voter.vote.rankings.sort[0..1].collect \
 104         { |ranking| ranking.candidate.id }
 105       preference_tally << voter.vote.rankings.sort.collect \
 106         { |ranking| ranking.candidate.id }
 107     end
 108
 109     @plurality_result = PluralityVote.new(plurality_tally).result
 110     @approval_result = ApprovalVote.new(approval_tally).result
 111     @condorcet_result = PureCondorcetVote.new(preference_tally).result
 112     @ssd_result = CloneproofSSDVote.new(preference_tally).result
 113     @borda_result = BordaVote.new(preference_tally).result
 114
 115     { 'plurality' => @plurality_result,
 116       'approval' => @approval_result,
 117       'condorcet' => @condorcet_result,
 118       'ssd' => @ssd_result,
 119       'borda' => @borda_result }
 120     end
 121
 122   def names_by_id
 123     names = Hash.new
 124
 125     competitors = self.candidates.sort.collect {|candidate| candidate.id}
 126     competitors.each do |candidate|
 127       names[candidate] = Candidate.find(candidate).name
 128     end
 129
 130     names
 131   end
 132
 133 end
 134
 135