module Bozo

  # Module mixed into the all Bozo executors that provides functionality for 
  # command execution and logging.
  module Runner

    # Returns the global parameters.
    attr_accessor :global_params

    # Returns the command parameters.
    attr_accessor :params

    # Returns the environment variables.
    attr_accessor :env
    
    # Returns the build configuration.
    attr_accessor :build_configuration

    # Returns whether the build is being run on a build server.
    def build_server?
      global_params[:build_server]
    end

    # Returns the environment the build is being execute in.
    def environment
      global_params[:environment]
    end

    # Executes a command line tool.
    #
    # Raises a `Bozo::ExecutionError` if the command responds with a non-zero
    # exit code.
    #
    # @param [Symbol] tool
    #     A friendly identifier for the tool.
    # @param [Array] args
    #     An array of arguments making up the command to execute.
    def execute_command(tool, args)
      args.flatten!

      executable = File.basename(args.first)
      arguments = args[1..-1].join(' ')

      puts "  #{tool} - #{executable} #{arguments}".color(:cyan).bright

      raise Bozo::ExecutionError.new(tool, args, $?.exitstatus) unless system args.join ' '
    end
    
    # Records a `debug` log message.
    #
    # @param [String] msg
    #   The message to log.
    def log_debug(msg)
      puts "  #{msg.bright.color(:black)}"
    end

    # Records a `fatal` log message.
    #
    # @param [String] msg
    #   The message to log.
    def log_fatal(msg)
      puts msg.color(:red).bright
    end

    # Records an `info` log message.
    #
    # @param [String] msg
    #   The message to log.
    def log_info(msg)
      puts msg.color(:cyan).bright
    end

    # Records a `warn` log message.
    #
    # @param [String] msg
    #   The message to log.
    def log_warn(msg)
      puts msg.color(:yellow).bright
    end
    # Returns the build version.
    def version
      build_configuration.version
    end

  end

end