require 'rails/generators/base'
require 'sugar-high/array'
require 'active_support/inflector'
require 'rails3_artifactor'
require 'logging_assist'

module Cancan
  module Generators
    class PermitsGenerator < Rails::Generators::Base
      desc "Creates a Permit for each role in 'app/permits' and ensures that the permit folder is added to Rails load path."

      argument     :roles,        :type => :array,      :default => [],               :desc => "Roles to create permits for"

      # ORM to use
      class_option :orm,          :type => :string,     :default => 'active_record',  :desc => "ORM to use"
      class_option :initializer,  :type => :boolean,    :default => true,             :desc => "Create Permits initializer"

      class_option :default_permits,    :type => :boolean,    :default => true, :desc => "Create default permits for guest and admin roles"

      source_root File.dirname(__FILE__) + '/templates'

      def main_flow      
        default_roles.each do |role|
          template_permit role
        end

        template_permit :any,     :any_permit 
        template_permit :system,  :barebones_permit
    
        permit_logic = base_logic
        get_roles.each do |role|      
          template_permit(role) if !skip_permit?(role)
        end    

        permits_initializer if permits_initializer?
      end
  
      protected

      include Rails3::Assist::BasicLogger
      extend Rails3::Assist::UseMacro
  
      use_helpers :app, :file, :special

      attr_accessor :permit_name, :permit_logic

      def default_roles
        [:guest, :admin]
      end

      def permits_initializer?
        options[:initializer]
      end

      def skip_permit? permit
        default_permits? && default_roles.include?(permit.to_sym) 
      end


      # TODO: merge with any registered roles in application
      def get_roles
        roles.uniq.to_symbols
      end

      def default_permits?
        options[:default_permits]    
      end

      def orm
        options[:orm]
      end

      def permits_initializer
        create_initializer :permits do 
          "Permits::Ability.orm = :#{orm}"
        end
      end 

      def template_permit name, template_name=nil
        permit_logic = send "#{name}_logic" if [:admin, :system, :any].include?(name)
        self.permit_name = name

        template "permit.rb", "app/permits/#{name}_permit.rb"
      end 

      def any_logic
        ""
      end

      def system_logic
        %{
          # allow to manage all and return :break to 
          # abort calling any other permissions
  
          request = options[:request]
          if request && request.host.localhost? && localhost_manager?
            can(:manage, :all) 
            return :break
          end    
    }
      end

      def base_logic
        %{
          return if !role_match? user

          # can :create, Comment
          # owns(user, Comment)
    }
      end
  
      def admin_logic
        %{
          return if !role_match? user
          can :manage, :all
    }
      end

        def guest_logic
          %{
            return if !role_match? user
            can :read, :all
      }
        end
    end
  end
end