Update namespacing

See: solidusio/solidus_support#48

In order to not have ambigious namespaces we need to layer decorators
another layer deep.

app/decorators/controllers/solidus_jwt/spree/api/base_controller_decorator.rb

@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+module SolidusJwt
+  module Spree
+    module Api
+      module BaseControllerDecorator
+        def self.prepended(base)
+          base.rescue_from JWT::DecodeError do
+            render "spree/api/errors/invalid_api_key", status: :unauthorized
+          end
+        end
+
+        ##
+        # Overrides Solidus
+        # @see https://github.com/solidusio/solidus/blob/master/api/app/controllers/spree/api/base_controller.rb
+        #
+        def load_user
+          return super if json_web_token.blank?
+
+          # rubocop:disable Naming/MemoizedInstanceVariableName
+          @current_api_user ||= ::Spree.user_class.for_jwt(json_web_token['sub'] || json_web_token['id'])
+          # rubocop:enable Naming/MemoizedInstanceVariableName
+        end
+
+        def json_web_token
+          @json_web_token ||= SolidusJwt.decode(api_key).first
+        rescue JWT::DecodeError
+          # Allow spree to try and authenticate if we still allow it. Otherwise
+          # raise an error
+          return if SolidusJwt::Config.allow_spree_api_key
+
+          raise
+        end
+
+        if SolidusSupport.api_available?
+          ::Spree::Api::BaseController.prepend self
+        end
+      end
+    end
+  end
+end

app/decorators/models/solidus_jwt/spree/user_decorator.rb

@@ -0,0 +1,58 @@
+# frozen_string_literal: true
+
+module SolidusJwt
+  module Spree
+    module UserDecorator
+      def self.prepended(base)
+        base.extend ClassMethods
+        base.has_many :auth_tokens, class_name: 'SolidusJwt::Token'
+      end
+
+      module ClassMethods
+        ##
+        # Find user based on subject claim in
+        # our json web token
+        # @see https://tools.ietf.org/html/rfc7519#section-4.1.2
+        #
+        # @example get user token
+        #   payload = SolidusJwt.decode(token).first
+        #   user = Spree::User.for_jwt(payload['sub'])
+        #
+        # @param sub [string] The subject claim of jwt
+        # @return [Spree.user_class, NilClass] If a match is found, returns the user,
+        #   otherwise, returns nil
+        #
+        def for_jwt(sub)
+          find_by(id: sub)
+        end
+      end
+
+      ##
+      # Generate a json web token
+      # @see https://github.com/jwt/ruby-jwt
+      # @return [String]
+      #
+      def generate_jwt(expires_in: nil)
+        SolidusJwt.encode(payload: as_jwt_payload, expires_in: expires_in)
+      end
+      alias generate_jwt_token generate_jwt
+
+      ##
+      # Serializes user attributes to hash and applies
+      # the sub jwt claim.
+      #
+      # @return [Hash] The payload for json web token
+      #
+      def as_jwt_payload
+        options = SolidusJwt::Config.jwt_options
+        claims = { sub: id }
+
+        as_json(options)
+          .merge(claims)
+          .as_json
+      end
+
+      ::Spree.user_class.prepend self
+    end
+  end
+end