class Forum < ActiveRecord::Base
  include Redmine::SafeAttributes
  has_many :topics, :class_name => 'Memo', :conditions => "#{Memo.table_name}.parent_id IS NULL", :order => "#{Memo.table_name}.created_at DESC"
  has_many :memos, :dependent => :destroy
  belongs_to :creator, :class_name => "User", :foreign_key => 'creator_id' 
  safe_attributes 'name',
  'description',
  'topic_count',
  'memo_count',
  'last_memo_id',
  'creator_id'
  validates_presence_of :name, :creator_id
  validates_length_of :name, maximum: 50
  validates_length_of :description, maximum: 255
  validates :name, :uniqueness => true
  
  acts_as_taggable
  scope :by_join_date, order("created_at DESC")

  def reset_counters!
    self.class.reset_counters!(id)
  end

  # Updates topic_count, memo_count and last_memo_id attributes for +board_id+
  def self.reset_counters!(forum_id)
    forum_id = forum_id.to_i
    update_all("topic_count = (SELECT COUNT(*) FROM #{Memo.table_name} WHERE forum_id=#{forum_id} AND parent_id IS NULL)," +
     " memo_count = (SELECT COUNT(*) FROM #{Memo.table_name} WHERE forum_id=#{forum_id} AND parent_id IS NOT NULL)," +
     " last_memo_id = (SELECT MAX(id) FROM #{Memo.table_name} WHERE forum_id=#{forum_id})",
     ["id = ?", forum_id])
  end 
end