# Markdown document renderer to LaTeX
class LatexRenderer
	super MdRenderer

	# Generate the LaTeX document wrapper
	#
	# The header includes:
	#  * document class
	#  * package importation
	#  * begin and end document directives
	var wrap_document = false is optional, writable

	# LaTeX document class
	#
	# Default is `article`.
	var document_class = "article" is optional, writable

	# LaTeX document page format
	#
	# Default is `letter`.
	var page_format = "letter" is optional, writable

	# LaTeX font size
	#
	# Default is `10pt`.
	var font_size = "10pt" is optional, writable

	# Use `listings` package for code blocks?
	var use_listings = false is optional, writable

	# LaTeX output under construction
	private var latex: Buffer is noinit

	# Render `document` as LaTeX
	redef fun render(document) do
		latex = new Buffer
		enter_visit(document)
		return latex.write_to_string
	end

	redef fun visit(node) do node.render_latex(self)

	# Indentation level
	var indent = 0

	# Add a raw `string` to the output
	#
	# Raw means that the string will not be escaped.
	fun add_raw(string: String) do latex.append string

	# Add `text` string to the output
	#
	# The string will be escaped.
	fun add_text(text: String) do latex.append latex_escape(text)

	# Add a blank line to the output
	fun add_line do
		if not latex.is_empty and latex.last != '\n' then
			latex.add '\n'
		end
	end

	# Add an indentation depending on `ident` level
	fun add_indent do latex.append " " * indent

	# Escape `string` to LaTeX
	fun latex_escape(string: String): String do
		var buffer = new Buffer
		for i in [0 .. string.length[ do
			var c = string.chars[i]
			if c == '>' then
				buffer.append "\\textgreater"
				continue
			else if c == '<' then
				buffer.append "\\textless"
				continue
			else if c == '\\' then
				buffer.append "\\textbackslash"
				continue
			else if escaped_chars.has(c) then
				buffer.add '\\'
			end
			buffer.add c
		end
		return buffer.to_s
	end

	# LaTeX characters to escape
	var escaped_chars = ['%', '$', '{', '}', '_', '#', '&']
end