# coding: utf-8

module Engine2
    class DeleteMetaBase < Meta

        def invoke_delete_db handler, ids
            begin
                model = assets[:model]
                model.db.transaction do
                    ids.each do |id|
                        keys = split_keys(id)
                        restrict = model.association_reflections.select do |name, rel|
                            case rel[:type]
                            when :one_to_many
                                !model.db[name].where(Hash[rel[:keys].zip(keys)]).empty?
                            when :many_to_many
                                !model.db[rel[:join_table]].where(Hash[rel[:left_keys].zip(keys)]).empty?
                            when :many_to_one
                            when :one_to_one
                            else
                                unsupported_association rel[:type]
                            end
                        end
                        raise Sequel::DestroyFailed.new("Blokujące relacje: #{restrict.map{|name, rel| name}.join(', ')}" ) unless restrict.empty?

                        rec = model.call(Hash[model.primary_keys.zip(keys)])
                        rec.destroy(transaction: false)
                        # model.where(model.primary_keys_hash(keys)).delete # model.dataset[model.primary_key => id].delete
                    end
                end
                {}
            rescue Sequel::NoExistingObject
                handler.halt_not_found LOCS[:no_entry]
            rescue Sequel::DestroyFailed => failure
                handler.halt_forbidden failure.error.to_s
            end
        end

    end

    class DeleteMeta < DeleteMetaBase
        include MetaDeleteSupport

        def invoke handler
            handler.permit id = handler.params[:id]
            invoke_delete_db(handler, [id])
        end
    end

    class BulkDeleteMeta < DeleteMetaBase
        include MetaBulkDeleteSupport

        def invoke handler
            ids = handler.param_to_json(:ids)
            handler.permit ids.is_a?(Array)
            invoke_delete_db(handler, ids)
        end
    end

end