# 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

module RightConf

  class RubyConfigurator

    # RVM version used to install rubies
    RVM_VERSION = '1.2.6'

    include Configurator

    register :ruby

    description "Installs ruby interpreter and rubygems.\n" +
                'Installs and uses rvm on supported (i.e. non-Windows) platforms'

    settings :ruby_version     => 'Ruby version using rvm notation (see "rvm list known")',
             :rubygems_version => 'Rubygems version, e.g. "1.3.7"',
             :gemset           => 'Gemset to be used for platforms supporting rvm'

    validate_has_settings :ruby_version, :rubygems_version

    # Switch to ruby version defined in settings
    # Use rvm and install it if needed
    #
    # === Return
    # true:: Always return true
    def run_linux
      check_rvm(RVM_VERSION)
      report_check("Checking whether #{ruby_version} is the active ruby")
      out = Command.execute('rvm', 'list').output
      if out =~ /^=> #{ruby_version.gsub('.', '\\.')}/
        report_success
      else
        report_failure
        report_check("Switching to #{ruby_version}")
        out = Command.execute('rvm', 'use', ruby_version).output
        case out
        when /is not installed\./
          report_failure
          report_fatal "Failed to install #{ruby}: #{@out}" if @out
          @out = install_ruby(ruby_version)
          run
          return true
        when /^Using /
          report_success
          check_rvmrc
          post_note 'Configuration required switching the active ruby, please "cd" into the project directory again to activate it'
        else
          report_fatal("Failed to use #{ruby_version}:\n#{out}")
        end
      end
      if gemset
        report_check("Switching to gemset #{gemset}")
        res = Command.execute('rvm', 'gemset', 'use',  gemset,
                             :abort_on_failure => "Failed to switch to gemset '#{gemset}'") 
        report_success
      end
      Command.set_prefix("rvm #{ruby_version}@#{gemset} exec --")
      true
    end
    alias :run_darwin :run_linux

    # Switch to ruby version defined in settings
    # TBD
    #
    # === Return
    # true:: Always return true
    def run_windows
    end

    protected

    # Check whether the right version of RVM is installed and install it if not
    #
    # === Parameters
    # version(String):: Version of RVM to be checked, e.g. '1.2.6'
    #
    # === Return
    # true:: Always return true
    def check_rvm(version)
      report_check("Checking that rvm #{version} is installed")
      out = Command.execute('rvm', '--version').output
      if out =~ /rvm #{RVM_VERSION.gsub('.', '\\.')}/
        report_success
      else
        report_failure
        report_check("Installing rvm #{version}")
        rvm_src = File.join(ENV['HOME'] || '/root', '.rvm/src')
        FileUtils.mkdir_p(rvm_src)
        Dir.chdir(rvm_src) do
          res = Command.execute('curl', '-O', '-f',
                                "http://rvm.beginrescueend.com/releases/rvm-#{version}.tar.gz",
                                :abort_on_failure => "Failed to download rvm #{version}")
          Command.execute('tar', 'zxf', "rvm-#{version}.tar.gz")
        end
        Dir.chdir(File.join(rvm_src, "rvm-#{version}")) do
          res = Command.execute('./install', :abort_on_failure => "Failed to install rvm #{version}")
        end
        report_success
      end
      true
    end

    # Install given ruby version using rvm
    #
    # === Parameters
    # ruby(String):: Ruby version compatible with rvm
    #
    # === Return
    # out(String):: Installation output
    def install_ruby(ruby)
      report_check("Installing #{ruby} (this will take a while, please be patient)")
      res = Command.execute('rvm', 'install', ruby)
      report_result(res.success?)
      res.output
    end

    # Check .rvmrc and its content
    #
    # === Return
    # true:: Always return true
    def check_rvmrc
      report_check('Setting up .rvmrc')
      begin
        File.open('.rvmrc', 'w') do |f|
          f.puts "rvm #{ruby_version}@#{gemset}"
          f.puts "type -P rconf &>/dev/null && { rconf; }"
          f.puts "type -P rconf &>/dev/null || { echo 'rconf not installed, skipping (see .rvmrc)'; }"
        end
        Command.execute('rvm', 'trust', 'rvmrc')
        report_success
      rescue Exception => e
        report_failure
        report_error(e.message)
      end
      true
    end

  end
end