module CoalescingPanda
  class PersistentSession < ActiveRecord::Base
    serialize :data, Hash
    belongs_to :coalescing_panda_lti_account, :class_name => 'CoalescingPanda::LtiAccount'
    validates :coalescing_panda_lti_account_id, presence: true

    after_initialize do
      self.session_key ||= SecureRandom.urlsafe_base64(60)
    end

    def self.create_from_launch(launch_params, account_id)
      session = PersistentSession.new(coalescing_panda_lti_account_id: account_id)
      session.data[:launch_params] = launch_params.to_unsafe_h
      session.data[:roles] = launch_params['roles'].split(',').map { |role|
        case role.downcase.strip
        when 'admin'
          :admin
        when 'urn:lti:instrole:ims/lis/administrator'
          :admin
        when 'learner'
          :student
        when 'instructor'
          :teacher
        when 'urn:lti:role:ims/lis/teachingassistant'
          :ta
        when 'contentdeveloper'
          :designer
        when 'urn:lti:instrole:ims/lis/observer'
          :observer
        else
          :none
        end
      }.uniq
      session.save!
      session
    end
  end
end