module Phlex::SGML::Elements

def __register_void_element__(method_name, tag: method_name.name.tr("_", "-"))
	class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
		# frozen_string_literal: true
		def #{method_name}(**attributes)
			context = @_context
			buffer = context.buffer
			fragment = context.fragments
			if fragment
				return if fragment.length == 0 # we found all our fragments already
				id = attributes[:id]
				if !context.in_target_fragment
				  if fragment[id]
						context.begin_target(id)
						target_found = true
					else
						return nil
					end
				end
			end
			if attributes.length > 0 # with attributes
				buffer << "<#{tag}" << (::Phlex::ATTRIBUTE_CACHE[attributes] ||= __attributes__(attributes)) << ">"
			else # without attributes
				buffer << "<#{tag}>"
			end
			context.end_target if target_found
			nil
		end
		alias_method :_#{method_name}, :#{method_name}
	RUBY
	__registered_elements__[method_name] = tag
	method_name
end

def __registered_elements__
	@__registered_elements__ ||= {}
end

def register_element(method_name, tag: method_name.name.tr("_", "-"))
	class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
		# frozen_string_literal: true
		def #{method_name}(**attributes)
			context = @_context
			buffer = context.buffer
			fragment = context.fragments
			target_found = false
			block_given = block_given?
			if fragment
				return if fragment.length == 0 # we found all our fragments already
				id = attributes[:id]
				if !context.in_target_fragment
				  if fragment[id]
						context.begin_target(id)
						target_found = true
					else
						yield(self) if block_given
						return nil
					end
				end
			end
			if attributes.length > 0 # with attributes
				if block_given # with content block
					buffer << "<#{tag}" << (Phlex::ATTRIBUTE_CACHE[attributes] ||= __attributes__(attributes)) << ">"
					original_length = buffer.bytesize
					content = yield(self)
					if original_length == buffer.bytesize
						case content
						when ::Phlex::SGML::SafeObject
							buffer << content.to_s
						when String
							buffer << ::Phlex::Escape.html_escape(content)
						when Symbol
							buffer << ::Phlex::Escape.html_escape(content.name)
						when nil
							nil
						else
							if (formatted_object = format_object(content))
								buffer << ::Phlex::Escape.html_escape(formatted_object)
							end
						end
					end
					buffer << "</#{tag}>"
				else # without content
					buffer << "<#{tag}" << (::Phlex::ATTRIBUTE_CACHE[attributes] ||= __attributes__(attributes)) << "></#{tag}>"
				end
			else # without attributes
				if block_given # with content block
					buffer << "<#{tag}>"
					original_length = buffer.bytesize
					content = yield(self)
					if original_length == buffer.bytesize
						case content
						when ::Phlex::SGML::SafeObject
							buffer << content.to_s
						when String
							buffer << ::Phlex::Escape.html_escape(content)
						when Symbol
							buffer << ::Phlex::Escape.html_escape(content.name)
						when nil
							nil
						else
							if (formatted_object = format_object(content))
								buffer << ::Phlex::Escape.html_escape(formatted_object)
							end
						end
					end
					buffer << "</#{tag}>"
				else # without content
					buffer << "<#{tag}></#{tag}>"
				end
			end
			#{'flush' if tag == 'head'}
			context.end_target if target_found
			nil
		end
	RUBY
	__registered_elements__[method_name] = tag
	method_name
end