# Copyright (C) 2011 RightScale, Inc, All Rights Reserved Worldwide.
#
# THIS PROGRAM IS CONFIDENTIAL AND PROPRIETARY TO RIGHTSCALE
# AND CONSTITUTES A VALUABLE TRADE SECRET. Any unauthorized use,
# reproduction, modification, or disclosure of this program is
# strictly prohibited. Any use of this program by an authorized
# licensee is strictly subject to the terms and conditions,
# including confidentiality obligations, set forth in the applicable
# License Agreement between RightScale.com, Inc. and
# the licensee

require 'shellwords'

module RightConf

  class Command

    include Singleton
    include ProgressReporter

    # Execute given command with given arguments
    #
    # === Parameters
    # command(String):: Command to run
    # args(Array):: Command arguments
    #
    # === Return
    # result(CommandResult):: Result of execution (output and exit status)
    def execute(command, *args)
      opts = {}
      if !args.empty? && args[-1].is_a?(Hash)
        opts = args[-1]
        args = args[0..-2]
      end
      res = Platform.dispatch(command, *args) { :execute }
      if !res.success? && msg = opts[:abort_on_failure]
        report_fatal("#{msg}: '#{command} #{args.join(' ')}' returned\n#{res.output}")
      end
      res
    end

    # Execute given command on *nix systems
    # 
    # === Parameters
    # command(String):: Command name
    # params(Array):: List of parameters to pass to command
    #
    # === Return
    # result(CommandResult):: Result of execution (output and exit status)
    def execute_linux(command, *args)
      out = `#{@prefix} #{Shellwords.join([command, *args])} 2>&1`
      result = CommandResult.new(out, $?.exitstatus)
    end
    alias :execute_darwin :execute_linux

    # Execute given command on Windows systems
    # 
    # === Parameters
    # command(String):: Command name
    # params(Array):: List of parameters to pass to command
    #
    # === Return
    # result(CommandResult):: Result of execution (output and exit status)
    def execute_windows(command, *args)
      raise 'TBD!'
    end

    # Set prefix to be used for all commands
    #
    # === Parameters
    # prefix(String):: Commands prefix
    #
    # === Return
    # true:: Always return true
    def set_prefix(prefix)
      @prefix = prefix
      true
    end

  end

  # Command results
  class CommandResult

    # Process output
    attr_reader :output

    # Process exit status
    attr_reader :status

    # Initialize output and exit status
    #
    # === Parameters
    # output(String):: Process output
    # status(Fixnum):: Process exit status
    def initialize(output, status)
      @output = output
      @status = status
    end

    # Whether process exited successfully
    #
    # === Return
    # true:: If process exited with status code 0
    # false:: Otherwise
    def success?
      @status == 0
    end

  end

end