18F/C2

class ProposalPolicy
  include ExceptionPolicy

  def initialize(user, record)
    super(user, record)
    @proposal = record
  end

  def can_complete!
    step_user! && pending_step! && not_canceled!
  end

  def can_edit!
    (admin? || requester!) && not_completed! && not_canceled!
  end

  alias_method :can_update!, :can_edit!

  def can_show!
    check(visible_proposals.exists?(@proposal.id), I18n.t("errors.policies.proposal.show_permission"))
  end

  alias_method :can_history!, :can_show!

  def can_create!
    slug_matches? || @user.admin?
  end
  alias_method :can_new!, :can_create!

  def can_cancel!
    (pending_step_user_or_delegate? || admin? || requester!) && not_canceled!
  end
  alias_method :can_cancel_form!, :can_cancel!

  protected

  def use_case_namespace
    cls = self.class.to_s
    cls.gsub("::#{cls.demodulize}", "")
  end

  def slug_matches?
    use_case_namespace.downcase == @user.client_slug
  end

  def restricted?
    ENV["RESTRICT_ACCESS"] == "true"
  end

  def requester?
    @proposal.requester_id == @user.id
  end

  def requester!
    check(requester?, I18n.t("errors.policies.proposal.requester_permission"))
  end

  def not_completed!
    check(
      !@proposal.completed?,
      I18n.t("errors.policies.proposal.completed")
    )
  end

  def not_canceled!
    check(!@proposal.canceled?, I18n.t("errors.policies.proposal.canceled"))
  end

  def step_user?
    @proposal.step_users.include?(@user) || @proposal.completers.exists?(@user.id)
  end

  def delegate?
    @proposal.delegate?(@user)
  end

  def admin?
    @user.admin?
  end

  def step_user!
    check(
      step_user? || delegate?,
      I18n.t("errors.policies.proposal.step_permission")
    )
  end

  def observer!
    check(@proposal.observers.include?(@user), I18n.t("errors.policies.proposal.observer_permission"))
  end

  def pending_step_user?
    @proposal.currently_awaiting_step_users.include?(@user)
  end

  def pending_delegate?
    UserDelegate.where(assigner_id: @proposal.currently_awaiting_step_users, assignee: @user).exists?
  end

  def pending_step_user_or_delegate?
    (pending_step_user? || pending_delegate?)
  end

  def pending_step!
    check(pending_step_user_or_delegate?, I18n.t("errors.policies.proposal.step_complete"))
  end

  def visible_proposals
    ProposalPolicy::Scope.new(@user, Proposal).resolve
  end
end