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 + 14.days - 1.second
  22   end
  23
  24   def other_methods
  25     if election_method
  26       @other_methods = ELECTION_TYPES.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 enddate=(date)
  38     date += 1.day
  39     date = Time.gm(*date)
  40     super(date)
  41   end
  42
  43   def votes
  44     votes = Array.new
  45     self.voters.each do |voter|
  46       votes << voter.vote
  47     end
  48     return votes
  49   end
  50
  51   def destroy
  52     self.candidates.each do |candidate|
  53       candidate.destroy
  54     end
  55     super
  56   end
  57
  58   def start_blockers
  59     reasons = []
  60     if self.candidates.length <= 1
  61       reasons << "You must have at least two candidates."
  62     end
  63
  64     if self.voters.length <= 1
  65       reasons << "You must have at least two voters."
  66     end
  67
  68     reasons
  69   end
  70
  71   def activate!
  72     self.active = 1
  73     self.save!
  74   end
  75
  76   def quickvote?
  77     self.class == 'QuickVote'
  78   end
  79
  80   def active?
  81     active == 1
  82   end
  83
  84   def done?
  85     active == 2
  86   end
  87
  88   def shortdesc
  89     shortdesc = description.split(/\n/)[0]
  90   end
  91
  92   def longdesc
  93     longdesc = description.split(/\n/)[1..-1].join("")
  94     longdesc.length > 0 ? longdesc : nil
  95   end
  96
  97   #Calculate Election Results
  98   def results
  99     # initalize the tallies to empty arrays
 100     preference_tally = Array.new
 101     plurality_tally = Array.new
 102     approval_tally = Array.new
 103
 104     self.voters.each do |voter|
 105       # skip if the voter has not voted or has an unconfirmed vote
 106       next unless voter.voted?
 107
 108       plurality_tally << voter.vote.rankings.sort[0].candidate.id
 109       approval_tally << voter.vote.rankings.sort[0..1].collect \
 110         { |ranking| ranking.candidate.id }
 111       preference_tally << voter.vote.rankings.sort.collect \
 112         { |ranking| ranking.candidate.id }
 113     end
 114
 115     @plurality_result = PluralityVote.new(plurality_tally).result
 116     @approval_result = ApprovalVote.new(approval_tally).result
 117     @condorcet_result = PureCondorcetVote.new(preference_tally).result
 118     @ssd_result = CloneproofSSDVote.new(preference_tally).result
 119     @borda_result = BordaVote.new(preference_tally).result
 120
 121     { 'plurality' => @plurality_result,
 122       'approval' => @approval_result,
 123       'condorcet' => @condorcet_result,
 124       'ssd' => @ssd_result,
 125       'borda' => @borda_result }
 126     end
 127
 128   def names_by_id
 129     names = Hash.new
 130
 131     competitors = self.candidates.sort.collect {|candidate| candidate.id}
 132     competitors.each do |candidate|
 133       names[candidate] = Candidate.find(candidate).name
 134     end
 135
 136     names
 137   end
 138
 139 end
 140
 141