# ===========================================================================
# Project:   Abbot - SproutCore Build Tools
# Copyright: ©2009 Apple Inc.
#            portions copyright @2006-2009 Sprout Systems, Inc.
#            and contributors
# ===========================================================================

module SC
  
  # Generates components for SproutCore. The generator allows the user
  # to quickly set up a SproutCore framework using any of the built in 
  # templates such as the project itself, apps, models, views, controllers 
  # and more
  # 
  # The template files will be copied to their target location and also be 
  # parsed through the Erubis templating system. Template file paths can 
  # contain instance variables in the form of _class_name_ which in turn would 
  # be the value of class_name once generated.
  # 
  # To develop a new generator, you can add it to the sproutcore/gen/ 
  # directory with the following file structure:
  #    gen/
  #      <generator_name>/   - singular directory name of the generator
  #         Buildfile        - contains all config options and build tasks
  #         README           - prints when generator is done
  #         templates/       - contains all the files you want to generate
  #         USAGE            - prints when user gives uses --help option
  # 
  class Tools
    
    no_tasks do
      def show_help(generator_name=nil, generator=nil)
        if generator_name
          if generator.nil?
            warn("There is no #{generator_name} generator") 
          else
            generator.log_usage
          end
        else
          SC.logger << "Available generators:\n"
          SC::Generator.installed_generators_for(project).each do |name|
            SC.logger << "  #{name}\n"
          end
          SC.logger << "Type sc-gen GENERATOR --help for specific usage\n\n"
        end
        return 0
      end
    end
    
    desc "sc-gen generator Namespace[.ClassName] [--target=TARGET_NAME] [--filename=FILE_NAME]", 
      "Generates SproutCore components"
    
    method_options(
      MANIFEST_OPTIONS.merge(:help       => :string,
                             :filename   => :string,
                             :target     => :string,
                             '--dry-run' => false,
                             :force      => false))
      
    def gen(*arguments)
      return show_help if arguments.empty?
      
      # backwards compatibility case: client is a synonym for 'app'
      name = arguments[0]=='client' ? 'app' : arguments[0]
      
      # Load generator
      generator_project = self.project || SC.builtin_project
      generator = generator_project.generator_for name,
        :arguments   => arguments,
        :filename    => options[:filename],
        :target_name => options[:target],
        :dry_run     => options['dry-run'],
        :force       => options[:force]

      # if no generator could be found, or if we just asked to show help,
      # just return the help...
      return show_help(name, generator) if generator.nil? || options[:help] 
      
      begin
        # Prepare generator and then log some debug info
        generator.prepare!
        info "Loading generator Buildfile at: #{generator.buildfile.loaded_paths.last}"
      
        debug "\nSETTINGS"
        generator.each { |k,v| debug("#{k}: #{v}") }
        
        # Now, run the generator
        generator.build!
        
      rescue Exception => error_message
        warn "For specific help on how to use this generator, type: sc-gen #{name} --help"
        fatal! error_message.to_s
      end

      SC.logger << "\n"
      generator.log_readme
      return 0
    end
    
  end
end