class WatchersOfUser < ActiveRecord::Base
  attr_accessible :user_id, :watcher_id
  belongs_to :user
  
  validates_uniqueness_of :watcher_id, :scope => :user_id
  validate :validate_user
  validate :validate_watcher
  validates_presence_of :watcher_id, :user_id
   
  def self.watch_user(watcher_id, user_id)
    unless user_id == watcher_id
      @watchers_of_user = WatchersOfUser.new
      @watchers_of_user.watcher_id = watcher_id
      @watchers_of_user.user_id = user_id
      @watchers_of_user.save
      true
    else
      false  
    end     
  end
  
  def cancel_watching_user
    self.class.cancel_watching_user(self.watcher_id, self.user_id)
  end
  
  def self.cancel_watching_user(watcher_id, user_id)
    self.delete_all(["user_id = ? and watcher_id = ?", user_id, watcher_id])
    true
  end
  
  def self.find_users(watcher_id)
    @user = WatchersOfUser.find_by_sql("select * from users where id in (select user_id from #{WatchersOfUser.table_name} where watcher_id = #{watcher_id})")
    @user
    # @watch_table_for_user=WatchersOfUser.where(:watcher_id => watcher_id)
    # @user = []
    # @watch_table_for_user.each do |watch|
      # @user.push(watch.user)
    # end
    # @user
  end
  
  def self.find_watchers(user_id)
    @watcher = WatchersOfUser.find_by_sql("select * from users where id in (select watcher_id from #{WatchersOfUser.table_name} where user_id = #{user_id})")
    @watcher
    # user = User.find(user_id)
    # @watch_table_for_watcher = user.watchers_of_users
    # @watcher = []
    # @watch_table_for_watcher.each do |watch|
      # user_temp = User.find(watch.watcher_id)
      # @watcher.push(user_temp)
    # end
    # @watcher
  end
  
  #验证user是否存在
  def validate_user
    errors.add :user_id, :invalid if user.nil? || !user.active?
  end
  
  #验证watcher是否存在
  def validate_watcher
    user = User.where("id = ?", watcher_id).to_a.first
    errors.add :watcher_id, :invalid if user.nil? || !user.active?
  end
end