class
	MARKDOWN_RENDERER

inherit
	ANY
		redefine
			default_create
		end

	EL_ZSTRING_CONSTANTS; XML_ZSTRING_CONSTANTS

	PUBLISHER_CONSTANTS

create
	default_create

feature {NONE} -- Initialization

	default_create
		do
			relative_page_dir := "."
		end

feature -- Access

	as_html (markdown: ZSTRING): ZSTRING
		do
			Result := markdown.twin
			across Escaped_square_brackets as table loop
				Result.replace_substring_all (table.key, table.item)
			end
			across Markup_substitutions as list loop
				list.item.substitute_html (Result)
			end
			across Link_substitutions as list loop
				if list.item.has_link (Result) then
					list.item.set_relative_page_dir (relative_page_dir)
					list.item.substitute_html (Result)
				end
			end
			Result.escape (Xml_escaper)

		-- "\lsqb;" -> "["
			across Escaped_square_brackets as table loop
				across Result.substring_index_list (table.item, False) as i loop
					Result [i.item] := '&'
				end
			end
			Result.reveal (Html_reserved)
		end

feature {NONE} -- Factory

	new_substitution (
		delimiter_start, delimiter_end, markup_open, markup_close: READABLE_STRING_GENERAL
	): MARKUP_SUBSTITUTION
		do
			create Result.make (delimiter_start, delimiter_end, markup_open, markup_close)
		end

	new_hyperlink_substitution (delimiter_start: READABLE_STRING_GENERAL): HYPERLINK_SUBSTITUTION
		do
			create Result.make (delimiter_start)
		end

	new_link_substitutions: EL_ARRAYED_LIST [HYPERLINK_SUBSTITUTION]
		do
			create Result.make (3)
			across << "[http://", "[https://", "[./" >> as list loop
				Result.extend (new_hyperlink_substitution (list.item))
			end
		end

feature {NONE} -- Internal attributes

	relative_page_dir: DIR_PATH
		-- class page relative to index page directory tree

feature {NONE} -- Constants

	Escaped_square_brackets: EL_ZSTRING_HASH_TABLE [ZSTRING]
		once
		-- cannot use '&' here because of XML escaping
			create Result.make_equal (3)
			Result ["\["] := "\lsqb;"
			Result ["\]"] := "\rsqb;"
		end

	Link_substitutions: EL_ARRAYED_LIST [HYPERLINK_SUBSTITUTION]
		once
			Result := new_link_substitutions
		end

	Markup_substitutions: ARRAYED_LIST [MARKUP_SUBSTITUTION]
		once
			create Result.make_from_array (<<
				new_substitution ("`", "'", "<em id=%"code%">", "</em>"),
				new_substitution ("**", "**", "<b>", "</b>"),
				new_substitution ("''", "''", "<i>", "</i>")
			>>)
		end

end