require 'apartment/migrator'
module ZuoraConnect
  module Controllers
    module Helpers
      extend ActiveSupport::Concern

      def authenticate_app_api_request
        ZuoraConnect::AppInstance.read_master_db do
          #Skip session for api requests
          request.session_options[:skip] = true

          Thread.current[:appinstance] = nil
          if ZuoraConnect.logger.is_a?(Ougai::Logger); ZuoraConnect.logger.with_fields = {}; end
          if Rails.logger.is_a?(Ougai::Logger); Rails.logger.with_fields = {}; end
          if defined?(ElasticAPM) && ElasticAPM.running?
            if ElasticAPM.respond_to?(:set_label)
              ElasticAPM.set_label(:trace_id, request.uuid) if defined?(ElasticAPM) && ElasticAPM.running?
            else
              ElasticAPM.set_label(:trace_id, request.uuid) if defined?(ElasticAPM) && ElasticAPM.running?
            end
          end

          ZuoraConnect::ZuoraUser.current_user_id = request.headers["Zuora-User-Id"]

          if request.headers["API-Token"].present?
            @appinstance = ZuoraConnect::AppInstance.find_by(:api_token => request.headers["API-Token"])
            ZuoraConnect.logger.debug("API REQUEST - API token") if @appinstance.present?
            check_instance
          elsif ZuoraConnect::AppInstance::INTERNAL_HOSTS.include?(request.headers.fetch("HOST", nil)) && request.headers['zuora-host'].present?
            zuora_host, zuora_entity_id, zuora_instance_id = [request.headers['zuora-host'], (request.headers['zuora-entity-ids'] || "").gsub('-',''), request.headers['zuora-instance-id']]
            zuora_host_mapping = {'origin-gateway.sbx.auw2.zuora.com' => 'rest.apisandbox.zuora.com',  'origin-gateway.prod.auw2.zuora.com' => 'rest.zuora.com'}
            zuora_host = zuora_host_mapping[zuora_host] if zuora_host_mapping.keys.include?(zuora_host)

            #Validate entity-ids present
            if zuora_entity_id.blank?
              render json: {"status": 401, "message": "zuora-entity-ids header was not supplied."}, status: :unauthorized
              return
            end
            #Select with instance id if present. Used where mulitple deployments are done.
            if zuora_instance_id.present?
              appinstances = ZuoraConnect::AppInstance.where("zuora_entity_ids ?& array[:entities] = true AND zuora_domain = :host AND id = :id", entities: [zuora_entity_id], host: zuora_host, id: zuora_instance_id.to_i)
            else
              appinstances = ZuoraConnect::AppInstance.where("zuora_entity_ids ?& array[:entities] = true AND zuora_domain = :host", entities: [zuora_entity_id], host: zuora_host)
            end

            if appinstances.size == 0
              render json: {"status": 401, "message": "Missing mapping or no deployment for '#{zuora_host}-#{zuora_entity_id}' ."}, status: :unauthorized
              return
            elsif appinstances.size > 1
              render json: {"status": 401, "message": "More than one app instance binded to host and entity ids. Please indicate correct instance via 'zuora-instance-id' header", "instances": appinstances.map {|instance| instance.id }.sort }, status: :unauthorized
              return
            else
              @appinstance = appinstances.first
              check_instance
            end

          elsif request.headers.fetch("Authorization", "").include?("Basic ")
            authenticate_or_request_with_http_basic do |username, password|
              @appinstance = ZuoraConnect::AppInstance.find_by(:token => password)
              @appinstance ||= ZuoraConnect::AppInstance.find_by(:api_token => password)
              ZuoraConnect.logger.debug("API REQUEST - Basic Auth") if @appinstance.present?
              check_instance
            end
          else
            check_instance
          end

          @zuora_user = ZuoraConnect::ZuoraUser.find_by(zuora_user_id: ZuoraConnect::ZuoraUser.current_user_id)
        end
      end

       #API ONLY
      def check_instance
        if defined?(@appinstance) && @appinstance.present?
          if @appinstance.new_session_for_api_requests(:params => params)
            @appinstance.new_session(:session => @appinstance.data_lookup(:session => session))
          end
          Thread.current[:appinstance] = @appinstance
          PaperTrail.whodunnit = "API User" if defined?(PaperTrail)
          ElasticAPM.set_user("API User")  if defined?(ElasticAPM) && ElasticAPM.running?
          return true
        else
          response.set_header('WWW-Authenticate', "Basic realm=\"Application\"")
          render json: {"status": 401, "message": "Access Denied"}, status: :unauthorized
          return false
        end
      end

      def authenticate_connect_app_request
        ZuoraConnect::AppInstance.read_master_db do
          Thread.current[:appinstance] = nil
          if ZuoraConnect.logger.is_a?(Ougai::Logger); ZuoraConnect.logger.with_fields = {}; end
          if Rails.logger.is_a?(Ougai::Logger); Rails.logger.with_fields = {}; end
          if defined?(ElasticAPM) && ElasticAPM.running?
            if ElasticAPM.respond_to?(:set_label)
              ElasticAPM.set_label(:trace_id, request.uuid)
            else
              ElasticAPM.set_label(:trace_id, request.uuid)
            end
          end

          if ZuoraConnect.configuration.mode == "Production"
            setup_instance_via_prod_mode
          else
            setup_instance_via_dev_mode
          end

          return if performed?

          if !defined?(@appinstance) || @appinstance.blank?
            render "zuora_connect/static/error_handled", :locals => {
              :title => "Application state could not be found.",
              :message => "Please relaunch application."
            }, :layout => false
            return
          end
          #Call .data_lookup with the current session to retrieve session. In some cases session may be stored/cache in redis
          #so data lookup provides a model method that can be overriden per app.
          if params[:controller] != 'zuora_connect/api/v1/app_instance' && params[:action] != 'drop'
            if @appinstance.new_session_for_ui_requests(:params => params)
              @appinstance.new_session(:session => @appinstance.data_lookup(:session => session))
            end
          end

          if session["#{@appinstance.id}::user::email"].present?
            ElasticAPM.set_user(session["#{@appinstance.id}::user::email"])  if defined?(ElasticAPM) && ElasticAPM.running?
            PaperTrail.whodunnit =  session["#{@appinstance.id}::user::email"] if defined?(PaperTrail)
          end

          locale = (session["#{@appinstance.id}::user::locale"] || "").gsub("_", "-")
          begin
            I18n.locale = locale.present? ? locale : @appinstance.locale
          rescue I18n::InvalidLocale => ex
            if locale.include?("-")
              locale = locale.split("-").first
              retry
            elsif locale != session["#{@appinstance.id}::user::language"]
              locale = session["#{@appinstance.id}::user::language"]
              retry
            end
            ZuoraConnect.logger.error(ex) if !ZuoraConnect::AppInstance::IGNORED_LOCALS.include?(ex.locale.to_s.downcase)
          end
          if @appinstance.user_timezone.blank?
            @appinstance.set_timezone(timezone: session["#{@appinstance.id}::user::timezone"], type: :default)
          end
        end
      rescue ZuoraConnect::Exceptions::InvalidCredentialSet => ex
        id = @appinstance.id
        ZuoraConnect::AppInstance.destroy(id)
        Apartment::Tenant.drop(id)
        render "zuora_connect/static/error_handled", :locals => {
          :title => "Application Setup Error",
          :message => "Application cannot be run using Zuora Session. Delete old application \
          deployment and create new with Zuora Basic or OAuth credentials."
        }, :layout => false
        return
      rescue ZuoraConnect::Exceptions::AccessDenied => ex
        respond_to do |format|
          format.html {
            render "zuora_connect/static/error_handled", :locals => {
                :title => "Application State Error",
                :message => ex.message
              }, status: 401, layout: false
          }
          format.js {
            render "zuora_connect/static/error_handled", :locals => {
                :title => "Application State Error",
                :message => ex.message
              }, status: 401, layout: false
          }
          format.json { render json: {'errors' => ex.message}, status: 401 }
          format.all { render json: ex.message, status: 401 }
        end
        return
      rescue => ex
        ZuoraConnect.logger.error("UI Authorization Error", ex)
        respond_to do |format|
          format.html { render 'zuora_connect/static/error_unhandled', :locals => {:exception => ex, :skip_exception => true}, status: 500, layout: false }
          format.js { render 'zuora_connect/static/error_unhandled', :locals => {:exception => ex, :skip_exception => true}, status: 500, layout: false}
        end
        return
      end

      def persist_connect_app_session
        if @appinstance.present?
          if defined?(Redis.current)
            @appinstance.cache_app_instance
          else
            session.merge!(@appinstance.save_data)
          end
        end
      end

      def check_connect_admin!(raise_error: false)
        if !(session["#{@appinstance.id}::admin"] || @appinstance.zuora_tenant_ids.include?("9"))
          raise ZuoraConnect::Exceptions::AccessDenied.new("User is not an authorized admin for this application") if raise_error

          respond_to do |format|
            format.html {
              render "zuora_connect/static/error_handled", :locals => {
                  :title => "Unauthorized",
                  :message => "User is not an authorized admin for this application"
                }, status: 401, :layout => false
            }
            format.js {
              render "zuora_connect/static/error_handled", :locals => {
                  :title => "Unauthorized",
                  :message => "User is not an authorized admin for this application"
                }, status: 401, :layout => false
            }
            format.json { render json: {'errors' => ex.message}, status: 401 }
            format.all { render json: ex.message, status: 401 }
          end
          return
        end
      end

      def check_connect_admin
        return session["#{@appinstance.id}::admin"]
      end

      def zuora_user
        return @zuora_user
      end

      def hallway_integration?
        return (request.headers['ZuoraCurrentEntity'].present? || cookies['ZuoraCurrentEntity'].present?)
      end

      def create_new_instance
        ZuoraConnect::AppInstance.read_master_db do
          Thread.current[:appinstance] = nil
          ZuoraConnect.logger.with_fields = {} if ZuoraConnect.logger.is_a?(Ougai::Logger)
          Rails.logger.with_fields = {} if Rails.logger.is_a?(Ougai::Logger)

          if defined?(ElasticAPM) && ElasticAPM.running? && ElasticAPM.respond_to?(:set_label)
            ElasticAPM.set_label(:trace_id, request.uuid)
          end

          zuora_host = request.headers['zuora-host']
          zuora_entity_id = (request.headers['zuora-entity-ids'] || '').gsub(
            '-',
            ''
          ).split(',').first

          # Validate host present
          if zuora_host.blank?
            render json: {
              status: 401,
              message: 'zuora-host header was not supplied.'
            }, status: :unauthorized
            return
          end

          # Validate entity-ids present
          if zuora_entity_id.blank?
            render json: {
              status: 401,
              message: 'zuora-entity-ids header was not supplied.'
            }, status: :unauthorized
            return
          end

          rest_domain = ZuoraAPI::Login.new(url: "https://#{zuora_host}").rest_domain
          app_instance_id = ZuoraConnect::AppInstance.where(
            'zuora_entity_ids ?& array[:entities] AND zuora_domain = :host',
            entities: [zuora_entity_id],
            host: rest_domain
          ).pluck(:id).first

          if app_instance_id.present?
            render json: {
              status: 409,
              message: 'Instance already exists.',
              app_instance_id: app_instance_id
            }, status: 409
          else
            Apartment::Tenant.switch!("public")
            retry_count = 3
            begin
              @appinstance = new_instance(
                next_instance_id,
                zuora_entity_id,
                rest_domain,
                tenant_id: request.headers['zuora-tenant-id'],
                retry_count: retry_count
              )
            rescue ActiveRecord::RecordNotUnique
              retry if (retry_count -= 1).positive?
              return
            end

            app_instance_id = @appinstance.id
          end

          begin
            Apartment::Tenant.switch!('public')
            Apartment::Tenant.create(app_instance_id.to_s)
          rescue Apartment::TenantExists
            ZuoraConnect.logger.debug('Tenant Already Exists')
          end
        end
      end

    private
      def setup_instance_via_prod_mode
        zuora_entity_id = request.headers['ZuoraCurrentEntity'] || cookies['ZuoraCurrentEntity']
        ZuoraConnect::ZuoraUser.current_user_id = '3'

        if zuora_entity_id.present?
          zuora_tenant_id = cookies['Zuora-Tenant-Id']
          zuora_user_id = cookies['Zuora-User-Id']
          zuora_host = request.headers['HTTP_X_FORWARDED_HOST'] || request.headers['HTTP_ZUORA_HOST'] || 'apisandbox.zuora.com'

          zuora_details = {'host' => zuora_host, 'user_id' => zuora_user_id, 'tenant_id' => zuora_tenant_id, 'entity_id' => zuora_entity_id}
          auth_headers = {}
          #Do we need to refresh session identity
          if request.headers["Zuora-Auth-Token"].present?
            zuora_client = ZuoraAPI::Oauth.new(url: "https://#{zuora_host}", bearer_token: request.headers["Zuora-Auth-Token"], entity_id: zuora_entity_id, oauth_session_expires_at: Time.now + 5.minutes )
          elsif cookies['ZSession'].present?
            zuora_client = ZuoraAPI::Basic.new(url: "https://#{zuora_host}", session: cookies['ZSession'], entity_id: zuora_entity_id)
            auth_headers.merge!({'Authorization' => "ZSession-a3N2w #{zuora_client.get_session(prefix: false, auth_type: :basic)}"})
          else
            render "zuora_connect/static/error_handled", :locals => {
              :title => "Missing Authorization Token",
              :message => "Zuora 'Zuora-Auth-Token' header and 'ZSession' cookie not present."
            }, :layout => false
            return
          end

          begin
            zuora_instance_id = params[:sidebar_launch].to_s.to_bool ? nil : (params[:app_instance_id] || session["appInstance"])

            #Identity blank or current entity different
            different_zsession = session["ZSession"] != cookies['ZSession']
            missmatched_entity = session["ZuoraCurrentEntity"] != zuora_entity_id
            missing_identity = session["ZuoraCurrentIdentity"].blank?

            if (missing_identity || missmatched_entity || different_zsession)
              zuora_details.merge!({'identity' => {'different_zsession' => different_zsession, 'missing_identity' => missing_identity, 'missmatched_entity' => missmatched_entity}})
              identity, response = zuora_client.rest_call(
                url: zuora_client.rest_endpoint("identity"),
                zuora_track_id: ZuoraConnect::RequestIdMiddleware.zuora_request_id
              )

              if zuora_entity_id != identity['entityId']
                if zuora_tenant_id.to_s == "10548"
                  session.clear
                  render "zuora_connect/static/error_handled", :locals => {
                    :title => "Security Testing",
                    :message => "Ya we know it you"
                  }, :layout => false
                  return
                else
                  raise ZuoraConnect::Exceptions::Error.new("Header entity id does not match identity call entity id.")
                end
              end

              ##
              # If the ZSession was refreshed, but it's still the same user and they aren't launching from the side bar,
              # we don't need to continue
              is_different_user = identity.slice("entityId", "tenantId", "userId", "userProfileId") != (session["ZuoraCurrentIdentity"] || {}).slice("entityId", "tenantId", "userId", "userProfileId")
              zuora_details["identity"]["entityId"] = identity['entityId']
              session["ZuoraCurrentIdentity"] = identity
              session["ZuoraCurrentEntity"] = identity['entityId']
              session["ZSession"] = cookies['ZSession']
              if is_different_user || params[:sidebar_launch].to_s.to_bool
                zuora_instance_id = nil
                ZuoraConnect.logger.debug("UI Authorization", zuora: zuora_details)
                client_describe, response = zuora_client.rest_call(
                  url: zuora_client.rest_endpoint("genesis/user/info").gsub('v1/', ''),
                  session_type: zuora_client.class == ZuoraAPI::Oauth ? :bearer : :basic,
                  headers: auth_headers,
                  zuora_track_id: ZuoraConnect::RequestIdMiddleware.zuora_request_id
                )
                session["ZuoraCurrentUserInfo"] = client_describe
              end
            end

            if zuora_instance_id.present?
              appinstances = ZuoraConnect::AppInstance.where("zuora_entity_ids ?& array[:entities] = true AND zuora_domain = :host AND id = :id", entities: [zuora_entity_id], host: zuora_client.rest_domain, id: zuora_instance_id.to_i).pluck(:id, :name)
            else
              #if app_instance_ids is present then permissions still controlled by connect
              if params[:app_instance_ids].present?
                navbar, response = zuora_client.rest_call(
                  url: zuora_client.rest_endpoint("navigation"),
                  zuora_track_id: ZuoraConnect::RequestIdMiddleware.zuora_request_id
                )
                urls = navbar['menus'].map {|x| x['url']}
                app_env = ENV["DEIS_APP"] || "xyz123"
                url = urls.compact.select {|url| File.basename(url).start_with?(app_env + '?')}.first
                if url.blank?
                  if navbar['menus'].map {|x| x['label']}.include?('Link Connect Account')
                    render "zuora_connect/static/error_handled", :locals => {
                      :title => "Link Account",
                      :message => "Link Connect account to gain access to application."
                    }, :layout => false
                    return
                  end
                  raise ZuoraConnect::Exceptions::APIError.new(message: "#{app_env} navbar url was blank", response: response)
                else
                  query_params = CGI.parse(URI.parse(url).query)
                  app_instance_ids = query_params["app_instance_ids"][0]
                  if app_instance_ids.present?
                    begin
                      task_ids = JSON.parse(Base64.urlsafe_decode64(app_instance_ids))

                      appinstances = ZuoraConnect::AppInstance.where(:id => task_ids).pluck(:id, :name)
                    rescue => ex
                      raise ZuoraConnect::Exceptions::APIError.new(message: "Failure in parsing the navbar urls.", response: response)
                    end
                  end
                end
              end
              appinstances ||= ZuoraConnect::AppInstance.where("zuora_entity_ids ?& array[:entities] = true AND zuora_domain = :host", entities: [zuora_entity_id], host: zuora_client.rest_domain).pluck(:id, :name)
            end

            zuora_user_id = cookies['Zuora-User-Id'] || session["ZuoraCurrentIdentity"]['userId'] || request.headers["Zuora-User-Id"]

            if appinstances.size == 1
              ZuoraConnect.logger.debug("Instance is #{appinstances.to_h.keys.first}")
              @appinstance = ZuoraConnect::AppInstance.find(appinstances.to_h.keys.first)
            end

            # One deployed instance with credentials
            if defined?(@appinstance) && !@appinstance['zuora_logins'].nil?
              @zuora_user = ZuoraConnect::ZuoraUser.update_id_response(
                zuora_user_id, zuora_entity_id, session["ZuoraCurrentIdentity"],
                @appinstance,
                session['ZuoraCurrentUserInfo']['permissions']
              )
              @zuora_user.session = session
              ZuoraConnect::ZuoraUser.current_user_id = zuora_user_id
              session["#{@appinstance.id}::user::localUserId"] = @zuora_user.id
              session["#{@appinstance.id}::user::email"] = session['ZuoraCurrentIdentity']["username"]
              session["#{@appinstance.id}::user::timezone"] = session['ZuoraCurrentIdentity']["timeZone"]
              session["#{@appinstance.id}::user::language"] = session['ZuoraCurrentIdentity']["language"]
              session["#{@appinstance.id}::user::locale"] = session['ZuoraCurrentIdentity']["locale"]
              session["appInstance"] = @appinstance.id

            #We have multiple, user must pick
            elsif appinstances.size > 1
              ZuoraConnect.logger.debug("User must select instance. #{@names}")
              render "zuora_connect/static/launch", :locals => {:names => appinstances.to_h}, :layout => false
              return

            #We have no deployed instance for this tenant
            else
              if ZuoraConnect.configuration.disable_provisioning
                raise ZuoraConnect::Exceptions::AccessDenied.new("Provisioning is suspended")
              end

              #Ensure user can access oauth creation API
              if !session["ZuoraCurrentUserInfo"]['permissions'].include?("permission.userManagement")
                Thread.current[:appinstance] = nil
                session["appInstance"] = nil
                render "zuora_connect/static/error_handled", :locals => {
                  :title => "Application can only complete its initial setup via platform administrator",
                  :message => "Please contact admin who has user managment permissions in tenant and have them click and finish setup."
                }, :layout => false
                return
              end
              Apartment::Tenant.switch!("public")
              retry_count = 3
              task_data = {}
              begin
                ActiveRecord::Base.transaction do
                  ActiveRecord::Base.connection.execute('LOCK public.zuora_users IN ACCESS EXCLUSIVE MODE')

                  unless defined?(@appinstance)
                    appinstances = ZuoraConnect::AppInstance.where("zuora_entity_ids ?& array[:entities] = true AND zuora_domain = :host", entities: [zuora_entity_id], host: zuora_client.rest_domain).pluck(:id, :name)

                    if appinstances.size > 0
                      redirect_to "https://#{zuora_host}/apps/newlogin.do?retURL=#{request.fullpath}&pos=0"
                      return
                    end
                  end

                  next_id = defined?(@appinstance) ? @appinstance.id : next_instance_id
                  if task_data.blank?
                    user = (ENV['DEIS_APP'] || "Application").split('-').map(&:capitalize).join(' ')
                    body = {
                      'userId' => zuora_user_id,
                      'entityIds' => [zuora_entity_id.unpack("a8a4a4a4a12").join('-')],
                      'customAuthorities' => [],
                      'additionalInformation' => {
                        'description' => "This user is for #{user} application.",
                        'name' => "#{user} API User #{next_id}"
                      }
                    }

                    oauth_response, response = zuora_client.rest_call(
                      method: :post,
                      body: body.to_json,
                      url: zuora_client.rest_endpoint("genesis/clients").gsub('v1/', ''),
                      session_type: zuora_client.class == ZuoraAPI::Oauth ? :bearer : :basic,
                      headers: auth_headers,
                      zuora_track_id: ZuoraConnect::RequestIdMiddleware.zuora_request_id
                    )

                    new_zuora_client = ZuoraAPI::Oauth.new(url: "https://#{zuora_host}", oauth_client_id: oauth_response["clientId"], oauth_secret: oauth_response["clientSecret"] )
                    if session["ZuoraCurrentUserInfo"].blank?
                      client_describe, response = new_zuora_client.rest_call(
                        url: zuora_client.rest_endpoint("genesis/user/info").gsub('v1/', ''), 
                        session_type: :bearer,
                        zuora_track_id: ZuoraConnect::RequestIdMiddleware.zuora_request_id
                      )
                    else
                      client_describe = session["ZuoraCurrentUserInfo"]
                    end

                    available_entities = client_describe["accessibleEntities"].select {|entity| entity['id'] == zuora_entity_id}
                    task_data = {
                      "id": next_id,
                      "name": client_describe["tenantName"],
                      "mode": "Collections",
                      "status": "Running",
                      ZuoraConnect::AppInstance::LOGIN_TENANT_DESTINATION => {
                        "tenant_type": "Zuora",
                        "username": session["ZuoraCurrentIdentity"]["username"],
                        "url": new_zuora_client.url,
                        "status": "Active",
                        "oauth_client_id": oauth_response['clientId'],
                        "oauth_secret": oauth_response['clientSecret'],
                        "authentication_type": "OAUTH",
                        "entities": available_entities.map {|e| e.merge({'displayName' => client_describe["tenantName"]})}
                      },
                      "tenant_ids": available_entities.map{|e| e['entityId']}.uniq,
                    }
                  end

                  if defined?(@appinstance)
                    @appinstance.zuora_logins = task_data
                    @appinstance.save(:validate => false)
                  else
                    @appinstance = new_instance(
                      next_id,
                      zuora_entity_id,
                      zuora_client.rest_domain,
                      task_data: task_data,
                      retry_count: retry_count
                    )
                  end
                end
              rescue ActiveRecord::RecordNotUnique
                retry if (retry_count -= 1).positive?
                return
              end

              Apartment::Tenant.switch!("public")
              begin
                Apartment::Tenant.create(@appinstance.id.to_s)
              rescue Apartment::TenantExists => ex
                ZuoraConnect.logger.debug("Tenant Already Exists")
              end
              @appinstance.refresh
              session["appInstance"] = @appinstance.id
            end

          rescue ZuoraAPI::Exceptions::ZuoraAPIAuthenticationTypeError => ex
            output_xml, input_xml, response = zuora_client.soap_call(errors: [], z_session: false, zuora_track_id: ZuoraConnect::RequestIdMiddleware.zuora_request_id) do |xml|
              xml['api'].getUserInfo
            end
            final_error = output_xml.xpath('//fns:FaultCode', 'fns' =>'http://fault.api.zuora.com/').text
            session.clear
            if final_error.blank?
              ZuoraConnect.logger.warn("UI Authorization Error", ex, response: { params: response.body })
            elsif final_error != "INVALID_SESSION"
              ZuoraConnect.logger.warn("UI Authorization Error", ex, response: { params: final_error })
            else
              ZuoraConnect.logger.info("UI Authorization Error", ex, response: { params: final_error })
            end
            redirect_to "https://#{zuora_host}/apps/newlogin.do?retURL=#{request.fullpath}&pos=1"
            return

          rescue ZuoraAPI::Exceptions::ZuoraAPIError, Exception => ex
            if ex.message.include?("Referenced User resource(s) not found") && ex.class == ZuoraAPI::Exceptions::ZuoraAPIError
              locals = {title: "Provisioning Error", message: "New tenants need to be provisioned by API Gateway('#{ex.message}'). Please contact support."}
              render "zuora_connect/static/error_handled", locals: locals, status: 200, layout: false
            else
              session.clear
              if defined?(ex.response) && ex.response.present? && defined?(ex.response.body)
                zuora_details.merge!({:error => ex.response.body})
              end
              ZuoraConnect.logger.error("UI Authorization Error", ex, zuora: zuora_details)

              respond_to do |format|
                format.html {
                  render "zuora_connect/static/error_unhandled", locals: {exception: ex, skip_exception: true}, layout: false, status: 500
                }
                format.js {
                  render "zuora_connect/static/error_unhandled", locals: {exception: ex, skip_exception: true}, layout: false, status: 500
                }
              end
            end
            return
          end
        elsif request["data"].present? && (request["connectInstanceId"].present? || /^([A-Za-z0-9+\/\-\_]{4})*([A-Za-z0-9+\/]{4}|[A-Za-z0-9+-_\/]{3}=|[A-Za-z0-9+\/]{2}==)$/.match(request["data"].to_s))
          session.clear
          values = JSON.parse(ZuoraConnect::AppInstance.decrypt_response(Base64.urlsafe_decode64(request["data"])))
          values.fetch("param_data", {}).each do |k ,v|
            params[k] = v
          end
          session["#{values["appInstance"]}::destroy"] = values["destroy"]
          session["appInstance"] = values["appInstance"]
          if values["current_user"]
            session["#{values["appInstance"]}::admin"] = values["current_user"]["admin"] ? values["current_user"]["admin"] : false
            session["#{values["appInstance"]}::user::timezone"] = values["current_user"]["timezone"]
            session["#{values["appInstance"]}::user::locale"] = values["current_user"]["locale"]
            session["#{values["appInstance"]}::user::email"] = values["current_user"]["email"]
          end

          @appinstance = ZuoraConnect::AppInstance.find_by(:id => values["appInstance"].to_i)

          if @appinstance.blank?
            if ZuoraConnect.configuration.disable_provisioning
              raise ZuoraConnect::Exceptions::AccessDenied.new("Provisioning is suspended")
            end

            Apartment::Tenant.switch!("public")
            begin
              Apartment::Tenant.create(values["appInstance"].to_s)
            rescue Apartment::TenantExists => ex
              ZuoraConnect.logger.debug("Tenant Already Exists")
            end
            mapped_values = {:api_token => values['api_token'], :token => values['api_token'], :access_token => values["access_token"], :refresh_token => values["refresh_token"], :oauth_expires_at => values["expires"]}
            @appinstance = ZuoraConnect::AppInstance.new(mapped_values.merge({:id => values["appInstance"].to_i}))
            @appinstance.save(:validate => false)
          else
            mapped_values = {:access_token => values["access_token"], :refresh_token => values["refresh_token"], :oauth_expires_at => values["expires"]}
            @appinstance.assign_attributes(mapped_values)
            if @appinstance.access_token_changed? && @appinstance.refresh_token_changed?
              @appinstance.save(:validate => false)
            else
              raise ZuoraConnect::Exceptions::AccessDenied.new("Authorization mismatch. Possible tampering with session.")
            end
          end
        else
          if session["appInstance"].present?
            @appinstance = ZuoraConnect::AppInstance.find_by(:id => session["appInstance"])
          else
            if ZuoraConnect::AppInstance::INTERNAL_HOSTS.include?(request.headers.fetch("HOST", nil)) 
              render "zuora_connect/application/ldap_login", :layout => false
              return
            else
              raise ZuoraConnect::Exceptions::AccessDenied.new("No application state or session found.")
            end
          end
        end
      end

      def next_instance_id
        min_instance_id = 24_999_999
        (ZuoraConnect::AppInstance.all.where("id > #{min_instance_id}").order(id: :desc).limit(1).pluck(:id).first || min_instance_id) + 1
      end

      def new_instance(id, zuora_entity_id, rest_domain, tenant_id: nil, task_data: nil, retry_count: 0)
        app_instance = ZuoraConnect::AppInstance.new(
          :id => id,
          :api_token => generate_token,
          :token => generate_token,
          :oauth_expires_at => Time.now + 1000.years,
          :zuora_domain => rest_domain,
          :zuora_entity_ids => [zuora_entity_id]
        )

        app_instance[:zuora_tenant_ids] = [tenant_id.to_s] if tenant_id.present?

        if task_data.nil?
          # no encryption
          app_instance['zuora_logins'] = task_data
        else
          # kms encrypt
          app_instance.zuora_logins = task_data
        end

        begin
          app_instance.save(:validate => false)
        rescue ActiveRecord::RecordNotUnique
          raise if retry_count > 1

          Thread.current[:appinstance] = nil
          session['appInstance'] = nil
          render 'zuora_connect/static/error_handled', :locals => {
            :title => 'Application could not create unique tokens.',
            :message => 'Please contact support or retry launching application.'
          }, :layout => false
          return
        end

        app_instance
      end

      def generate_token
        rand(36**64).to_s(36)
      end
    end
  end
end