# The specific markdown decorator used internally to process MDoc object.
#
# You should use the various methods of `MDoc` like `MDoc::html_documentation`
#
# The class is public so specific behavior can be plugged on it.
class NitdocDecorator
	super HTMLDecorator

	private var toolcontext = new ToolContext

	# The currently processed mdoc.
	#
	# Unfortunately, this seems to be the simpler way to get the currently processed `MDoc` object.
	var current_mdoc: nullable MDoc = null

	redef fun add_code(v, block) do
		var meta = block.meta or else "nit"

		# Do not try to highlight non-nit code.
		if meta != "nit" and meta != "nitish" then
			v.add "<pre class=\"{meta}\"><code>"
			v.emit_in block
			v.add "</code></pre>\n"
			return
		end
		# Try to parse code
		var code = block.raw_content
		var ast = toolcontext.parse_something(code)
		if ast isa AError then
			v.add "<pre class=\"{meta}\"><code>"
			v.emit_in block
			v.add "</code></pre>\n"
			return
		end
		v.add "<pre class=\"nitcode\"><code>"
		var hl = new HtmlightVisitor
		hl.line_id_prefix = ""
		hl.highlight_node(ast)
		v.add(hl.html)
		v.add "</code></pre>\n"
	end

	redef fun add_span_code(v, text, from, to) do
		# Try to parse it
		var code = code_from_text(text, from, to)
		var ast = toolcontext.parse_something(code)

		if ast isa AError then
			v.add "<code class=\"rawcode\">"
			append_code(v, text, from, to)
		else
			v.add "<code class=\"nitcode\">"
			var hl = new HtmlightVisitor
			hl.line_id_prefix = ""
			hl.highlight_node(ast)
			v.add(hl.html)
		end
		v.add "</code>"
	end

	private fun code_from_text(buffer: Text, from, to: Int): String do
		var out = new FlatBuffer
		for i in [from..to[ do out.add buffer[i]
		return out.write_to_string
	end
end