socialforge/app/models/contest.rb

class Contest < ActiveRecord::Base
  attr_accessible :description, :invite_code, :invite_code_halt, :is_delete, :is_public, :name, :user_id, :visits

  include ContestsHelper

  belongs_to :user
  has_many :contest_members, :include => [:principal, :roles], :conditions => "#{Principal.table_name}.type='User' AND #{Principal.table_name}.status=#{Principal::STATUS_ACTIVE}"
  has_many :memberships, :class_name => 'ContestMember'
  has_many :member_principals, :class_name => 'ContestMember',
           :include => :principal,
           :conditions => "#{Principal.table_name}.type='Group' OR (#{Principal.table_name}.type='User' AND #{Principal.table_name}.status=#{Principal::STATUS_ACTIVE})"
  has_many :principals, :through => :member_principals, :source => :principal
  has_many :users, :through => :members
  has_many :contestants, :class_name => 'ContestantForContest', :source => :user
  has_many :works

  has_many :contest_acts, :class_name => 'ContestActivity',:as =>:contest_act ,:dependent => :destroy
  has_many :contest_activities
  has_many :contest_messages, :class_name =>'ContestMessage', :as => :contest_message, :dependent => :destroy

  acts_as_attachable
  validates_format_of  :name,:with =>/^[^ ]+[a-zA-Z0-9_\u4e00-\u9fa5\s\S]*$/

  before_destroy :delete_all_members
  #after_create :act_as_contest_activity

  scope :visible, lambda {|*args| where(Contest.where("is_delete =?", 0).visible_condition(args.shift || User.current, *args)) }

  # 删除竞赛所有成员
  def delete_all_members
    if self.contest_members && self.contest_members.count > 0
      me, mr = ContestMember.table_name, ContestMemberRole.table_name
      connection.delete("DELETE FROM #{mr} WHERE #{mr}.contest_member_id IN (SELECT #{me}.id FROM #{me} WHERE #{me}.contest_id = #{id})")
      ContestMember.delete_all(['contest_id = ?', id])
    end
  end

  def self.visible_condition(user, options={})
    allowed_to_condition(user, :view_course, options)
  end

  def self.allowed_to_condition(user, permission, options={})
    perm = Redmine::AccessControl.permission(permission)
    base_statement = ("#{Contest.table_name}.is_delete <> 1")
    if perm && perm.contest_module
      base_statement << " AND #{Contest.table_name}.id IN (SELECT em.contest_id FROM #{EnabledModule.table_name} em WHERE em.name='#{perm.contest_module}')"
    end

    if options[:contest]
      contest_statement = "#{Contest.table_name}.id = #{options[:contest].id}"
      contest_statement << " OR (#{Contest.table_name}.lft > #{options[:contest].lft} AND #{Contest.table_name}.rgt < #{options[:contest].rgt})" if options[:with_subcontests]
      base_statement = "(#{contest_statement}) AND (#{base_statement})"
    end

    if user.admin?
      base_statement
    else
      statement_by_role = {}
      unless options[:contest_member]
        role = user.logged? ? Role.non_member : Role.anonymous
        if role.allowed_to?(permission)
          statement_by_role[role] = "#{Contest.table_name}.is_public = #{connection.quoted_true}"
        end
      end
      if user.logged?
        user.contests_by_role.each do |role, contests|
          if role.allowed_to?(permission) && contests.any?
            statement_by_role[role] = "#{Contest.table_name}.id IN (#{contests.collect(&:id).join(',')})"
          end
        end
      end
      if statement_by_role.empty?
        "1=0"
      else
        if block_given?
          statement_by_role.each do |role, statement|
            if s = yield(role, user)
              statement_by_role[role] = "(#{statement} AND (#{s}))"
            end
          end
        end
        "((#{base_statement}) AND (#{statement_by_role.values.join(' OR ')}))"
      end
    end
  end

  # 竞赛动态公共表记录
  def act_as_contest_activity
    self.contest_acts << ContestActivity.new(:user_id => self.user_id,:contest_id => self.id)
  end

  # 延迟生成邀请码
  def invite_code
    return generate_invite_code
  end

  # 生成邀请码
  # 如果已有改邀请码，则重新生成
  CODES = %W(2 3 4 5 6 7 8 9 A B C D E F G H J K L N M O P Q R S T U V W X Y Z)
  def generate_invite_code
    code = read_attribute(:invite_code)
    if !code || code.size < 4
      code = CODES.sample(4).join
      return generate_invite_code if Project.where(invite_code: code).present?
      update_attribute(:invite_code, code)
    end
    code
  end
end