class Chef
  class Provider
    class Package
      class Macports < Chef::Provider::Package

        provides :macports_package

        def load_current_resource
          @current_resource = Chef::Resource::Package.new(@new_resource.name)
          @current_resource.package_name(@new_resource.package_name)

          @current_resource.version(current_installed_version)
          Chef::Log.debug("#{@new_resource} current version is #{@current_resource.version}") if @current_resource.version

          @candidate_version = macports_candidate_version

          if !@new_resource.version and !@candidate_version
            raise Chef::Exceptions::Package, "Could not get a candidate version for this package -- #{@new_resource.name} does not seem to be a valid package!"
          end

          Chef::Log.debug("#{@new_resource} candidate version is #{@candidate_version}") if @candidate_version

          @current_resource
        end

        def current_installed_version
          command = "port installed #{@new_resource.package_name}"
          output = get_response_from_command(command)

          response = nil
          output.each_line do |line|
            match = line.match(/^.+ @([^\s]+) \(active\)$/)
            response = match[1] if match
          end
          response
        end

        def macports_candidate_version
          command = "port info --version #{@new_resource.package_name}"
          output = get_response_from_command(command)

          match = output.match(/^version: (.+)$/)

          match ? match[1] : nil
        end

        def install_package(name, version)
          unless @current_resource.version == version
            command = "port#{expand_options(@new_resource.options)} install #{name}"
            command << " @#{version}" if version and !version.empty?
            shell_out!(command)
          end
        end

        def purge_package(name, version)
          command = "port#{expand_options(@new_resource.options)} uninstall #{name}"
          command << " @#{version}" if version and !version.empty?
          shell_out!(command)
        end

        def remove_package(name, version)
          command = "port#{expand_options(@new_resource.options)} deactivate #{name}"
          command << " @#{version}" if version and !version.empty?

          shell_out!(command)
        end

        def upgrade_package(name, version)
          # Saving this to a variable -- weird rSpec behavior
          # happens otherwise...
          current_version = @current_resource.version

          if current_version.nil? or current_version.empty?
            # Macports doesn't like when you upgrade a package
            # that hasn't been installed.
            install_package(name, version)
          elsif current_version != version
            shell_out!( "port#{expand_options(@new_resource.options)} upgrade #{name} @#{version}" )
          end
        end

        private
        def get_response_from_command(command)
          output = nil
          status = shell_out(command)
          begin
            output = status.stdout
          rescue Exception
            raise Chef::Exceptions::Package, "Could not read from STDOUT on command: #{command}"
          end
          unless status.exitstatus == 0 || status.exitstatus == 1
            raise Chef::Exceptions::Package, "#{command} failed - #{status.insect}!"
          end
          output
        end
      end
    end
  end
end