require 'migration_assist'

module ActiveRecord 
  module Generators
    class RolesMigrationGenerator < Rails::Generators::NamedBase 
      include RailsAssist::Migration
      
      desc "Generates user role migrations" 

      # name is the user model to generate roles for      

      class_option :strategy, :type => :string, :aliases => "-s", :default => 'inline_role', 
                   :desc => "Role strategy to use (admin_flag, role_string, one_role, many_roles, roles_mask)"

      class_option :roles, :type => :array, :aliases => "-r", :default => [], :desc => "Valid roles"
      class_option :default_roles, :type => :boolean, :default => true, :desc => "Use default roles :admin and :base"
      class_option :logfile, :type => :string,   :default => nil,   :desc => "Logfile location"
      class_option :logging,            :type => :boolean,  :aliases => "-l",   :default => false,      :desc => "Logging on?"
      class_option :reverse, :type => :boolean, :alias => "-r", :default => false, :desc => "Create a remove migration for reversing a strategy"

      def self.source_root
        @source_root ||= File.expand_path("../templates", __FILE__)
      end

      def main
        if logging?
          require 'logging_assist'
          self.class.send :include, Rails3::Assist::BasicLogger
          logger.add_logfile :logfile => logfile if logfile
        end

        valid_strategy?
        run_migration
      end
      
      protected                  

      def valid_strategy?
        if !strategies.include?(strategy.to_sym)
          logger.info "Unknown role strategy #{strategy}"  if logging?
          raise ArgumentError, "Unknown role strategy #{strategy}"
        end
      end

      def default_roles
        options[:default_roles] ? [:admin, :guest] : []
      end

      def roles_to_add
        @roles_to_add ||= default_roles.concat(options[:roles]).to_symbols.uniq
      end

      def run_migration            
        logger.debug "Create migration for role_strategy: #{strategy}" if logging?
        migration_name = "add_#{strategy}_strategy"
        target_migration_name = reverse? ? reverse_migration_name(migration_name) : migration_name
        migration_template "#{migration_name}.erb", "db/migrate/#{target_migration_name}" 
        generated_migration = latest_migration_file(migration_dir, target_migration_name)
        reverse_migration!(generated_migration) if generated_migration && reverse?
      end

      def logfile
        options[:logfile]
      end

      def logging?
        options[:logging]
      end

      def strategies
        [:admin_flag, :role_string, :one_role, :many_roles, :roles_mask]
      end
       
      def reverse?
        options[:reverse]
      end
        
      def table_name
        name.tableize
      end
      
      def strategy
        options[:strategy]
      end
    end
  end
end