# A `Decorator` is used to emit mardown into a specific format.
# Default decorator used is `HTMLDecorator`.
interface Decorator

	# Kind of processor used
	type PROCESSOR: MarkdownProcessor

	# Render a single plain char.
	#
	# Redefine this method to add special escaping for plain text.
	fun add_char(v: PROCESSOR, c: Char) do v.addc c

	# Render a ruler block.
	fun add_ruler(v: PROCESSOR, block: BlockRuler) is abstract

	# Render a headline block with corresponding level.
	fun add_headline(v: PROCESSOR, block: BlockHeadline) is abstract

	# Render a paragraph block.
	fun add_paragraph(v: PROCESSOR, block: BlockParagraph) is abstract

	# Render a code or fence block.
	fun add_code(v: PROCESSOR, block: BlockCode) is abstract

	# Render a blockquote.
	fun add_blockquote(v: PROCESSOR, block: BlockQuote) is abstract

	# Render an unordered list.
	fun add_unorderedlist(v: PROCESSOR, block: BlockUnorderedList) is abstract

	# Render an ordered list.
	fun add_orderedlist(v: PROCESSOR, block: BlockOrderedList) is abstract

	# Render a list item.
	fun add_listitem(v: PROCESSOR, block: BlockListItem) is abstract

	# Render an emphasis text.
	fun add_em(v: PROCESSOR, text: Text) is abstract

	# Render a strong text.
	fun add_strong(v: PROCESSOR, text: Text) is abstract

	# Render a strike text.
	#
	# Extended mode only (see `MarkdownProcessor::ext_mode`)
	fun add_strike(v: PROCESSOR, text: Text) is abstract

	# Render a link.
	fun add_link(v: PROCESSOR, link: Text, name: Text, comment: nullable Text) is abstract

	# Render an image.
	fun add_image(v: PROCESSOR, link: Text, name: Text, comment: nullable Text) is abstract

	# Render an abbreviation.
	fun add_abbr(v: PROCESSOR, name: Text, comment: Text) is abstract

	# Render a code span reading from a buffer.
	fun add_span_code(v: PROCESSOR, buffer: Text, from, to: Int) is abstract

	# Render a text and escape it.
	fun append_value(v: PROCESSOR, value: Text) is abstract

	# Render code text from buffer and escape it.
	fun append_code(v: PROCESSOR, buffer: Text, from, to: Int) is abstract

	# Render a character escape.
	fun escape_char(v: PROCESSOR, char: Char) is abstract

	# Render a line break
	fun add_line_break(v: PROCESSOR) is abstract

	# Generate a new html valid id from a `String`.
	fun strip_id(txt: String): String is abstract

	# Found headlines during the processing labeled by their ids.
	fun headlines: ArrayMap[String, HeadLine] is abstract
end