module Graphql::Generators::FieldExtractor

def column_type_string(column)
  column.name == "id" ? "ID" : column.type.to_s.camelize
end

def fields
  columns = []
  columns += (klass&.columns&.map { |c| generate_column_string(c) }  || [])
  columns + custom_fields
end

def generate_column_string(column)
  name = column.name
  required = column.null ? "" : "!"
  type = column_type_string(column)
  "#{name}:#{required}#{type}"
end

def klass
  @klass ||= Module.const_get(name.camelize)
rescue NameError
  @klass = nil
end