module Padrino
  module Generators
    module Components
      module Orms

        module DatamapperGen
          DM = (<<-DM).gsub(/^ {10}/, '')
          module DatabaseSetup
            def self.registered(app)
              app.configure               { DataMapper.logger = logger }
              app.configure(:development) { DataMapper.setup(:default, "sqlite3://your_dev_db_here") }
              app.configure(:production)  { DataMapper.setup(:default, "sqlite3://your_production_db_here") }
              app.configure(:test)        { DataMapper.setup(:default, "sqlite3://your_test_db_here") }
            rescue ArgumentError => e
              logger.error "Database options need to be configured within 'config/database.rb'!" if app.logging?
            end
          end
          DM

          def setup_orm
            require_dependencies 'dm-core', 'dm-validations'
            create_file("config/database.rb", DM)
            empty_directory('app/models')
          end

          DM_MODEL = (<<-MODEL).gsub(/^ {10}/, '')
          class !NAME!
            include DataMapper::Resource

            # property <name>, <type>
            property :id, Serial
            !FIELDS!
          end
          MODEL

          def create_model_file(name, fields)
            model_path = app_root_path('app/models/', "#{name.to_s.underscore}.rb")
            return false if File.exist?(model_path)
            model_contents = DM_MODEL.gsub(/!NAME!/, name.to_s.downcase.camelize)
            field_tuples = fields.collect { |value| value.split(":") }
            field_tuples.collect! { |field, kind| kind =~ /datetime/i ? [field, 'DateTime'] : [field, kind] } # fix datetime
            column_declarations = field_tuples.collect { |field, kind|"property :#{field}, #{kind.camelize}" }.join("\n  ")
            model_contents.gsub!(/!FIELDS!/, column_declarations)
            create_file(model_path, model_contents)
          end

          DM_MIGRATION = (<<-MIGRATION).gsub(/^ {10}/, '')
          migration !VERSION!, :!FILENAME! do
            up do
              !UP!
            end

            down do
              !DOWN!
            end
          end
          MIGRATION

          DM_MODEL_UP_MG =  (<<-MIGRATION).gsub(/^ {6}/, '')
          create_table :!TABLE! do
            column :id, Integer, :serial => true
            !FIELDS!
          end
          MIGRATION

          DM_MODEL_DOWN_MG =  (<<-MIGRATION).gsub(/^ {10}/, '')
          drop_table :!TABLE!
          MIGRATION

          def create_model_migration(migration_name, name, columns)
            output_model_migration(migration_name, name, columns,
                 :column_format => lambda { |field, kind| "column :#{field}, #{kind.camelize}" },
                 :base => DM_MIGRATION, :up => DM_MODEL_UP_MG, :down => DM_MODEL_DOWN_MG)
          end

          DM_CHANGE_MG = (<<-MIGRATION).gsub(/^ {6}/, '')
          modify_table :!TABLE! do
            !COLUMNS!
          end
          MIGRATION

          def create_migration_file(migration_name, name, columns)
            output_migration_file(migration_name, name, columns,
                :base => DM_MIGRATION, :change_format => DM_CHANGE_MG,
                :add => lambda { |field, kind| "add_column :#{field}, #{kind.camelize}"  },
                :remove => lambda { |field, kind| "drop_column :#{field}" }
                )
          end
        end

      end
    end
  end
end