4 files changed, 130 insertions, 0 deletions
diff --git a/app/models/user_settings/dsl.rb b/app/models/user_settings/dsl.rb
new file mode 100644
index 000000000..26238bbbe
--- /dev/null
+++ b/app/models/user_settings/dsl.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module UserSettings::DSL
+  module ClassMethods
+    def setting(key, options = {})
+      @definitions ||= {}
+
+      UserSettings::Setting.new(key, options).tap do |s|
+        @definitions[s.key] = s
+      end
+    end
+
+    def namespace(key, &block)
+      @definitions ||= {}
+
+      UserSettings::Namespace.new(key).configure(&block).tap do |n|
+        @definitions.merge!(n.definitions)
+      end
+    end
+
+    def keys
+      @definitions.keys
+    end
+
+    def definition_for(key)
+      @definitions[key.to_sym]
+    end
+
+    def definition_for?(key)
+      @definitions.key?(key.to_sym)
+    end
+  end
+
+  def self.included(base)
+    base.extend ClassMethods
+  end
+end
diff --git a/app/models/user_settings/glue.rb b/app/models/user_settings/glue.rb
new file mode 100644
index 000000000..02066a411
--- /dev/null
+++ b/app/models/user_settings/glue.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module UserSettings::Glue
+  def to_model
+    self
+  end
+
+  def to_key
+    ''
+  end
+
+  def persisted?
+    false
+  end
+
+  def type_for_attribute(key)
+    self.class.definition_for(key)&.type
+  end
+
+  def has_attribute?(key) # rubocop:disable Naming/PredicateName
+    self.class.definition_for?(key)
+  end
+end
diff --git a/app/models/user_settings/namespace.rb b/app/models/user_settings/namespace.rb
new file mode 100644
index 000000000..b8f7e092e
--- /dev/null
+++ b/app/models/user_settings/namespace.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+class UserSettings::Namespace
+  attr_reader :name, :definitions
+
+  def initialize(name)
+    @name        = name.to_sym
+    @definitions = {}
+  end
+
+  def configure(&block)
+    instance_eval(&block)
+    self
+  end
+
+  def setting(key, options = {})
+    UserSettings::Setting.new(key, options.merge(namespace: name)).tap do |s|
+      @definitions[s.key] = s
+    end
+  end
+end
diff --git a/app/models/user_settings/setting.rb b/app/models/user_settings/setting.rb
new file mode 100644
index 000000000..5f5504254
--- /dev/null
+++ b/app/models/user_settings/setting.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+class UserSettings::Setting
+  attr_reader :name, :namespace, :in
+
+  def initialize(name, options = {})
+    @name          = name.to_sym
+    @default_value = options[:default]
+    @namespace     = options[:namespace]
+    @in            = options[:in]
+  end
+
+  def default_value
+    if @default_value.respond_to?(:call)
+      @default_value.call
+    else
+      @default_value
+    end
+  end
+
+  def type
+    case default_value
+    when TrueClass, FalseClass
+      ActiveModel::Type::Boolean.new
+    else
+      ActiveModel::Type::String.new
+    end
+  end
+
+  def type_cast(value)
+    if type.respond_to?(:cast)
+      type.cast(value)
+    else
+      value
+    end
+  end
+
+  def to_a
+    [key, default_value]
+  end
+
+  def key
+    if namespace
+      "#{namespace}.#{name}".to_sym
+    else
+      name
+    end
+  end
+end