# frozen_string_literal: true

module Sessions
  class AssertUserConcurrent
    ERROR_CODE = "user_concurrent_stream"

    def self.with_lock(session, action: "start")
      new(session, action: action).with_lock { yield }
    end

    def initialize(session, action: "start")
      @session = session
      @action = action.to_s
    end

    def with_lock
      occupying = nil

      User.transaction do
        User.lock.find(@session.user_id) if @session.user_id.present?
        occupying = occupying_session
        yield if occupying.nil?
      end

      return if occupying.nil?

      StreamConcurrencyViolation.record!(
        attempted: @session,
        occupying: occupying,
        action: @action
      )
      raise Teams::EntitlementError.new(
        I18n.t("api.errors.user_concurrent_stream"),
        code: ERROR_CODE
      )
    end

    private

    def occupying_session
      return if @session.user_id.blank?

      StreamSession.broadcasting
                   .where(user_id: @session.user_id)
                   .where.not(id: @session.id)
                   .includes(:user, match: { team: :club })
                   .order(Arel.sql("COALESCE(started_at, updated_at) DESC"))
                   .first
    end
  end
end