require "inspec/fetcher"
require "inspec/metadata"

module SourceReaders
  class InspecReader < Inspec.source_reader(1)
    name "inspec"
    priority 10

    def self.resolve(target)
      return new(target, "inspec.yml") if target.files.include?("inspec.yml")

      nil
    end

    attr_reader :metadata, :tests, :libraries, :data_files

    # This create a new instance of an InSpec profile source reader
    #
    # @param [FileProvider] target An instance of a FileProvider object that can list files and read them
    # @param [String] metadata_source eg. inspec.yml or metadata.rb
    def initialize(target, metadata_source)
      @target     = target
      @metadata   = load_metadata(metadata_source)
      @tests      = load_tests
      @libraries  = load_libs
      @data_files = load_data_files
    end

    private

    def load_metadata(metadata_source)
      Inspec::Metadata.from_ref(
        metadata_source,
        @target.read(metadata_source),
        nil
      )
    rescue Psych::SyntaxError => e
      raise "Unable to parse inspec.yml: line #{e.line}, #{e.problem} #{e.context}"
    rescue => e
      raise "Unable to parse #{metadata_source}: #{e.class} -- #{e.message}"
    end

    def find_all
      @target.files.find_all do |path|
        yield path
      end
    end

    def load_all paths
      paths.map { |path| [path, @target.read(path)] }.delete_if { |_file, file| file.nil? }.to_h
    end

    def load_tests
      paths = find_all { |path|
        path.start_with?("controls") && path.end_with?(".rb")
      }
      load_all paths
    end

    def load_libs
      paths = find_all { |path|
        path.start_with?("libraries") && path.end_with?(".rb")
      }
      load_all paths
    end

    def load_data_files
      paths = find_all { |path|
        path.start_with?("files" + File::SEPARATOR)
      }
      load_all paths
    end
  end
end