require 'lib/string_helper'
require 'db/mongo/models/stack_template/stack_template_factory'

module Devops
  module StackPresets
    class Base

      def id
        StringHelper.underscore_class(self.class)
      end

      def to_hash
        {id: id, template_body: template_body}
      end

      # attrs should include
      #   'provider'
      #   'stack'
      #   'parameters'
      #   'project'
      #   'deploy_env'
      def create_stack_from_preset(attrs)
        provider = attrs.fetch('provider')
        template_name = find_or_create_stack_template!(provider)

        stack_attrs = attrs.merge(
          'id' => attrs['stack'],
          'stack_template' => template_name
        )

        Model::StackFactory.create(provider, stack_attrs)
      end

      def template_body
        @template_body ||= File.read("lib/stack_presets/#{id}.#{template_file_extension}")
      end

      # some templates may be YAML files
      def template_file_extension
        :json
      end

      private

      def find_or_create_stack_template!(provider)
        name = stack_template_name(provider)
        begin
          stack_template = Devops::Api2.settings.mongo.stack_template(name)
          update_stack_template(stack_template) if stack_template.template_body != template_body
        rescue RecordNotFound
          create_stack_template(provider)
        end
        name
      end

      def stack_template_name(provider)
        "#{id}_#{provider}_preset"
      end

      def create_stack_template(provider)
        stack_template = Model::StackTemplateFactory.create(provider, {
          'id' => stack_template_name(provider),
          'provider' => provider,
          'template_body' => template_body
        })
        Devops::Api2.settings.mongo.stack_template_insert(stack_template)
      end

      def update_stack_template(stack_template)
        stack_template.template_body = template_body
        Devops::Api2.settings.mongo.stack_template_update(stack_template)
      end

    end
  end
end