#
# Copyright:: Copyright (c) 2014 Chef Software Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

require "ffi_yajl"
require "chef-dk/exceptions"
require "chef-dk/policyfile/source_uri"
require "chef/server_api"

module ChefDK
  module Policyfile
    class ChefServerCookbookSource
      attr_reader :uri
      attr_reader :preferred_cookbooks
      attr_reader :chef_config

      def initialize(uri, chef_config: nil)
        @uri = SourceURI.parse(uri)
        @http_connections = {}
        @chef_config = chef_config
        @preferred_cookbooks = []
        yield self if block_given?
      end

      def default_source_args
        [:chef_server, uri]
      end

      def ==(other)
        other.kind_of?(self.class) && other.uri == uri && other.preferred_cookbooks == preferred_cookbooks
      end

      def preferred_for(*cookbook_names)
        preferred_cookbooks.concat(cookbook_names)
      end

      def preferred_source_for?(cookbook_name)
        preferred_cookbooks.include?(cookbook_name)
      end

      def universe_graph
        @universe_graph ||= begin
          full_chef_server_graph.inject({}) do |normalized_graph, (cookbook_name, metadata_by_version)|
            normalized_graph[cookbook_name] = metadata_by_version.inject({}) do |deps_by_version, (version, metadata)|
              deps_by_version[version] = metadata["dependencies"]
              deps_by_version
            end
            normalized_graph
          end
        end
      end

      def source_options_for(cookbook_name, cookbook_version)
        {
          chef_server: uri.to_s,
          version: cookbook_version,
          http_client: http_connection_for(uri.to_s),
        }
      end

      def null?
        false
      end

      def desc
        "chef_server(#{uri})"
      end

      private

      def http_connection_for(base_url)
        @http_connections[base_url] ||= Chef::ServerAPI.new(base_url,
                                                       signing_key_filename: chef_config.client_key,
                                                       client_name: chef_config.node_name)
      end

      def full_chef_server_graph
        @full_chef_server_graph ||=
          begin
            http_connection_for(uri.to_s).get("/universe")
          end
      end
    end
  end
end