class Event < ActiveRecord::Base
  set_table_name "event_calendar_events"
  
  include ActionView::Helpers::TextHelper
  
  include EventInstanceMethods

  has_many :attendees
  has_and_belongs_to_many :links, :join_table => 'event_calendar_events_links'

  validates_presence_of :name, :event_type, :start_on
  
  searchable_by :name, :event_type, :location, :description
  
  acts_as_revisable :revision_class_name => 'EventRevision', :on_delete => :revise
  
  scope :past, where(sanitize_sql_array(["end_on < '%s'", Date.current]))
  scope :future, where(sanitize_sql_array(["start_on > '%s'", Date.current]))
  scope :current, where(sanitize_sql_array(["end_on >= '%s'", Date.current]))
  scope :between, lambda{ |start_datetime, end_datetime|
    where(["start_on BETWEEN ? AND ? OR end_on BETWEEN ? AND ?",
      start_datetime, end_datetime, start_datetime, end_datetime])
  }
  
  validate :sane_dates
  
  before_validation do
    if one_day? && ((end_on.present? && start_on.present? && end_on <= start_on) ||
                    (end_on.blank? && start_on.present?))
      unless changed_attributes.include?(:revisable_deleted_at)
        self.end_on = start_on + 1.hour
      end
    end
  end
  
  before_save :adjust_to_utc_from_timezone

  private

    def sane_dates
      if start_on and end_on and start_on > end_on
        errors.add :end_on, "cannot be before the start date"
      end
    end
    
    def adjust_to_utc_from_timezone
      return true if deleted?
      tz_offset = start_on.in_time_zone(timezone).utc_offset
      self.start_on = self.start_on - tz_offset
      self.end_on = self.end_on - tz_offset
    end
  protected
  public  
    
    def self.existing_event_types
      select('DISTINCT event_type').map(&:event_type).reject { |ev| ev.blank? }.sort
    end
    
    def participants
      return [] if attendees.count == 0
      attendees.all.collect do |attendee|
        attendee.participant
      end
    end

    def to_s
      "#{name} (#{start_on} #{end_on ? ' - ' + end_on.to_s : ''})"
    end
end