class Ability
  include CanCan::Ability

  # Initializes the ability class
  def initialize(user)
    # Order Abilities
    # (Check https://github.com/CanCanCommunity/cancancan/wiki/Ability-Precedence)
    # Check roles of user, using rolify. Role name is *case sensitive*
    # user.is_organizer? or user.has_role? :organizer
    # user.is_cfp_of? Conference or user.has_role? :cfp, Conference
    # user.is_info_desk_of? Conference
    # user.is_volunteer_coordinator_of? Conference
    # user.is_attendee_of? Conference
    # The following is wrong because a user will only have 'cfp' role for a specific conference
    # user.is_cfp? # This is always false

    user ||= User.new

    # This is what sets up the different abilities
    if user.new_record?
      not_signed_in
    else
      # This maps the actionables name of the role to its name in the DB.
      roles = Role::ACTIONABLES.map {|i| i.parameterize.underscore}
      # Checks if the user does not have any role and is not an admin
      if (user.roles.pluck(:name) & roles).empty? && !user.is_admin
        signed_in(user)
      else
        signed_in_with_roles(user)
      end
    end
  end

  # Abilities for not signed in users (guests)
  def not_signed_in
    can [:index], Conference
    can [:show], Conference do |conference|
      conference.splashpage && conference.splashpage.public == true
    end
    # Can view the schedule
    can [:schedule], Conference do |conference|
      conference.program.cfp && conference.program.schedule_public
    end

    can :show, Event do |event|
      event.state == 'confirmed'
    end

    # can view Commercials of confirmed Events
    can :show, Commercial, commercialable_type: 'Event', commercialable_id: Event.where(state: 'confirmed').pluck(:id)
    can :show, User
    unless CONFIG['authentication']['ichain']['enabled']
      can [:show, :create], Registration do |registration|
        registration.new_record?
      end
      can :show, Event do |event|
        event.new_record?
      end

      can [:new, :create], Event do |event|
        event.program.cfp_open? && event.new_record?
      end
    end
  end

  # Abilities for signed in users
  def signed_in(user)
    # Abilities from not_signed_in user are also inherited
    not_signed_in

    can :manage, User, id: user.id

    can :manage, Registration, user_id: user.id

    can :index, Ticket
    can :manage, TicketPurchase, user_id: user.id

    can [:create, :destroy], Subscription, user_id: user.id

    can :manage, Event do |event|
      event.users.include?(user)
    end
    # can create an event until the last day of a conference
    can :create, Event, program_id: Conference.where('end_date >= ?', Date.today).map { |conference| conference.program.id}.compact

    # can manage the commercials of their own events
    can :manage, Commercial, commercialable_type: 'Event', commercialable_id: user.events.pluck(:id)
  end

  # Abilities for signed in users with roles
  def signed_in_with_roles(user)
    # Abilities from not_signed_in and signed_in are also inherited
    signed_in(user)

    signed_in_with_organizer_role(user) if user.has_role? :organizer, :any
    signed_in_with_cfp_role(user) if user.has_role? :cfp, :any
    signed_in_with_info_desk_role(user) if user.has_role? :info_desk, :any
    signed_in_with_volunteers_coordinator_role(user) if user.has_role? :volunteer_coordinator, :any

    # for users with any role
    can :access, Admin
    can [:show], Conference
    can :index, Commercial, commercialable_type: 'Conference'
    cannot [:edit, :update, :destroy], Question, global: true
    # for admins
    can :manage, :all if user.is_admin

    cannot :destroy, Program
    # Do not delete venue, when there are rooms being used
    cannot :destroy, Venue do |venue|
      venue.conference.program.events.where.not(room_id: nil).any?
    end
  end

  def signed_in_with_organizer_role(user)
    # ids of all the conferences for which the user has the 'organizer' role
    conf_ids_for_organizer = []
    conf_ids_for_organizer =
        Conference.with_role(:organizer, user).pluck(:id) if user.has_role? :organizer, :any

    can [:new, :create], Conference if user.has_role?(:organizer, :any)
    can :manage, Conference, id: conf_ids_for_organizer
    can :manage, Splashpage, conference_id: conf_ids_for_organizer
    can :manage, Contact, conference_id: conf_ids_for_organizer
    can :manage, EmailSettings, conference_id: conf_ids_for_organizer
    can :manage, Campaign, conference_id: conf_ids_for_organizer
    can :manage, Target, conference_id: conf_ids_for_organizer
    can :manage, Commercial, commercialable_type: 'Conference',
                             commercialable_id: conf_ids_for_organizer
    can :manage, Registration, conference_id: conf_ids_for_organizer
    can :manage, RegistrationPeriod, conference_id: conf_ids_for_organizer
    can :manage, Question, conference_id: conf_ids_for_organizer
    can :manage, Question do |question|
      !(question.conferences.pluck(:id) & conf_ids_for_organizer).empty?
    end
    can :manage, Vposition, conference_id: conf_ids_for_organizer
    can :manage, Vday, conference_id: conf_ids_for_organizer
    can :manage, Program, conference_id: conf_ids_for_organizer
    can :manage, Cfp, program: { conference_id: conf_ids_for_organizer}
    can :manage, Event, program: { conference_id: conf_ids_for_organizer}
    can :manage, EventType, program: { conference_id: conf_ids_for_organizer}
    can :manage, Track, program: { conference_id: conf_ids_for_organizer}
    can :manage, DifficultyLevel, program: { conference_id: conf_ids_for_organizer}
    can :manage, Commercial, commercialable_type: 'Event',
                             commercialable_id: Event.where(program_id: Program.where(conference_id: conf_ids_for_organizer).pluck(:id)).pluck(:id)
    can :manage, Venue, conference_id: conf_ids_for_organizer
    can :manage, Lodging, conference_id: conf_ids_for_organizer
    can :manage, Room, venue: { conference_id: conf_ids_for_organizer}
    can :manage, Sponsor, conference_id: conf_ids_for_organizer
    can :manage, SponsorshipLevel, conference_id: conf_ids_for_organizer
    can :manage, Ticket, conference_id: conf_ids_for_organizer
    can :index, Comment, commentable_type: 'Event',
                         commentable_id: Event.where(program_id: Program.where(conference_id: conf_ids_for_organizer).pluck(:id)).pluck(:id)
  end

  def signed_in_with_cfp_role(user)
    # ids of all the conferences for which the user has the 'cfp' role
    conf_ids_for_cfp = []
    conf_ids_for_cfp =
      Conference.with_role(:cfp, user).pluck(:id) if user.has_role? :cfp, :any

    can :manage, Event, program: { conference_id: conf_ids_for_cfp }
    can :manage, EventType, program: { conference_id: conf_ids_for_cfp }
    can :manage, Track, program: { conference_id: conf_ids_for_cfp }
    can :manage, DifficultyLevel, program: { conference_id: conf_ids_for_cfp }
    can :manage, EmailSettings, conference_id: conf_ids_for_cfp
    can :manage, Room, venue: { conference_id: conf_ids_for_cfp }
    can :show, Venue, conference_id: conf_ids_for_cfp
    can :manage, Cfp, program: { conference_id: conf_ids_for_cfp }
    can :manage, Program, conference_id: conf_ids_for_cfp
    can :manage, Commercial, commercialable_type: 'Event',
                             commercialable_id: Event.where(program_id: Program.where(conference_id: conf_ids_for_cfp).pluck(:id)).pluck(:id)
    can :index, Comment, commentable_type: 'Event',
                         commentable_id: Event.where(program_id: Program.where(conference_id: conf_ids_for_cfp).pluck(:id)).pluck(:id)
  end

  def signed_in_with_info_desk_role(user)
    # ids of all the conferences for which the user has the 'info_desk' role
    conf_ids_for_info_desk = []
    conf_ids_for_info_desk =
        Conference.with_role(:info_desk, user).pluck(:id) if user.has_role? :info_desk, :any

    can :manage, Registration, conference_id: conf_ids_for_info_desk
    can :manage, Question, conference_id: conf_ids_for_info_desk
    can :manage, Question do |question|
      !(question.conferences.pluck(:id) & conf_ids_for_info_desk).empty?
    end
  end

  def signed_in_with_volunteers_coordinator_role(user)
    # ids of all the conferences for which the user has the 'volunteers_coordinator' role
    conf_ids_for_volunteers_coordinator = []
    conf_ids_for_volunteers_coordinator =
        Conference.with_role(:volunteer_coordinator, user).pluck(:id) if user.has_role? :volunteer_coordinator, :any

    can :manage, Vposition, conference_id: conf_ids_for_volunteers_coordinator
    can :manage, Vday, conference_id: conf_ids_for_volunteers_coordinator
  end
end