%% Copyright (c) 2018, Loïc Hoguin <[email protected]>
%%
%% Permission to use, copy, modify, and/or distribute this software for any
%% purpose with or without fee is hereby granted, provided that the above
%% copyright notice and this permission notice appear in all copies.
%%
%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-module(asciideck_to_html).
-export([translate/2]).
translate(AST, Opts) ->
Output0 = ast(AST),
Output1 = maybe_header_footer(Output0, Opts),
{CompressExt, Output} = case Opts of
#{compress := gzip} -> {".gz", zlib:gzip(Output1)};
_ -> {"", Output1}
end,
case Opts of
#{outdir := Path, outfile := Filename} ->
file:write_file(binary_to_list(iolist_to_binary(
[Path, "/", Filename, ".html", CompressExt])), Output);
#{outdir := Path} ->
Filename = filename_from_ast(AST),
file:write_file(binary_to_list(iolist_to_binary(
[Path, "/", Filename, ".html", CompressExt])), Output);
_ ->
Output
end.
maybe_header_footer(Body, #{no_header_footer := _}) ->
Body;
maybe_header_footer(Body, _Opts) ->
[
"<!DOCTYPE html>\n"
"<html lang=\"en\">\n"
"<head>\n"
"<meta charset=\"utf-8\"/>\n"
"<title>TODO title</title>\n" %% @todo
"</head>\n"
"<body>\n",
Body,
"</body>\n"
"</html>\n"
].
filename_from_ast([{section_title, #{level := 0}, Filename, _}|_]) ->
Filename.
%% Loop over all types of AST nodes.
ast(AST) ->
fold(AST, fun ast_node/1).
fold(AST, Fun) ->
lists:reverse(lists:foldl(
fun(Node, Acc) -> [Fun(Node)|Acc] end,
[], AST)).
ast_node(Node={Type, _, _, _}) ->
try
case Type of
section_title -> section_title(Node);
paragraph -> paragraph(Node);
listing_block -> listing_block(Node);
passthrough_block -> passthrough_block(Node);
list -> list(Node);
table -> table(Node);
block_macro -> block_macro(Node);
comment_line -> comment_line(Node);
_ -> ast_error({unknown_type, Node})
end
catch C:E:S ->
ast_error({crash, C, E, S, Node})
end.
ast_error(Error) ->
[
"<p class=\"asciideck-error\">",
html_encode(unicode:characters_to_binary(io_lib:format("~p", [Error]))),
"</p>"
].
%% Section titles.
section_title({section_title, Attrs=#{level := Level}, Title, _}) ->
LevelC = $1 + Level,
ID = case Attrs of
#{<<"id">> := ID0} -> ID0;
_ -> id_from_title(Title)
end,
["<h", LevelC, " id=\"", ID, "\">", inline(Title), "</h", LevelC, ">\n"].
%% Asciidoc User Guide 8.4.2
%% @todo Handle cases where the title is repeated in the same document.
id_from_title(Title) ->
ID0 = unicode:characters_to_binary(string:to_lower(unicode:characters_to_list(Title))),
ID1 = <<if
C >= $a, C =< $z -> <<C/utf8>>;
C >= $0, C =< $9 -> <<C/utf8>>;
true -> <<$_>>
end || <<C/utf8>> <= ID0>>,
ID = string:strip(unicode:characters_to_list(ID1), both, $_),
[$_, unicode:characters_to_binary(ID)].
%% Paragraphs.
paragraph({paragraph, _, Text, _}) ->
["<p>", inline(Text), "</p>\n"].
%% Listing blocks.
listing_block({listing_block, Attrs, Listing0, _}) ->
Listing = case Attrs of
#{1 := <<"source">>, 2 := _} ->
try asciideck_source_highlight:filter(Listing0, Attrs) catch C:E:S -> io:format("~p ~p ~p~n", [C, E, S]), exit(bad) end;
_ ->
["<pre>", html_encode(Listing0), "</pre>"]
end,
[
"<div class=\"listingblock\">",
case Attrs of
#{<<"title">> := Title} ->
["<div class=\"title\">", inline(Title), "</div>\n"];
_ ->
[]
end,
"<div class=\"content\">",
Listing,
"</div></div>\n"
].
%% Passthrough blocks.
passthrough_block({passthrough_block, _, HTML, _}) ->
HTML.
%% Lists.
list({list, #{type := bulleted}, Items, _}) ->
["<ul>", fold(Items, fun list_item/1), "</ul>\n"];
list({list, #{type := numbered}, Items, _}) ->
["<ol>", fold(Items, fun list_item/1), "</ol>\n"];
list({list, #{type := labeled}, Items, _}) ->
["<dl>", fold(Items, fun labeled_list_item/1), "</dl>\n"].
list_item({list_item, _, [{paragraph, _, Text, _}|AST], _}) ->
[
"<li>",
inline(Text), "\n",
ast(AST),
"</li>\n"
].
labeled_list_item({list_item, #{label := Label}, AST, _}) ->
[
"<dt>", inline(Label), "</dt>\n",
"<dd>",
ast(AST),
"</dd>\n"
].
%% Tables.
table({table, Attrs, [{row, _, Head, _}|Rows], _}) ->
[
"<table rules=\"all\" width=\"100%\" frame=\"border\"
cellspacing=\"0\" cellpadding=\"4\">\n",
case Attrs of
#{<<"title">> := Caption} -> ["<caption>", inline(Caption), "</caption>"];
_ -> []
end,
"<thead><tr>", table_head(Head), "</tr></thead>"
"<tbody>", table_body(Rows), "</tbody>"
"</table>\n"
].
table_head(Cells) ->
[["<th>", table_cell(AST), "</th>\n"]
|| {cell, _, AST, _} <- Cells].
table_body(Rows) ->
[["<tr>", table_body_cells(Cells), "</tr>\n"]
|| {row, _, Cells, _} <- Rows].
table_body_cells(Cells) ->
[["<td>", table_cell(AST), "</td>\n"]
|| {cell, _, AST, _} <- Cells].
table_cell(AST0) ->
AST = [Node || Node={Type, _, _, _} <- AST0, Type =/= comment_line],
case AST of
[{paragraph, _, Text, _}] ->
inline(Text);
_ ->
ast(AST)
end.
%% Block macros.
block_macro({block_macro, #{name := <<"image">>,
target := Target, 1 := Caption}, _, _}) ->
["<img src=\"", html_encode(Target), "\" "
"alt=\"", html_encode(Caption), "\"/>"].
%% Comment lines are printed in the generated file
%% but are not visible in viewers.
comment_line({comment_line, _, Text, _}) ->
["<!-- ", html_encode(Text), "-->\n"].
%% Inline formatting.
inline(Text) when is_binary(Text) ->
html_encode(Text);
inline({link, #{target := Target}, Text, _}) ->
["<a href=\"", html_encode(Target), "\">", html_encode(Text), "</a>"];
inline({xref, #{id := ID}, Text, _}) ->
["<a href=\"#", html_encode(ID), "\">", html_encode(Text), "</a>"];
inline({emphasized, _, Text, _}) ->
["<em>", inline(Text), "</em>"];
inline({strong, _, Text, _}) ->
["<strong>", inline(Text), "</strong>"];
inline({inline_literal_passthrough, _, Text, _}) ->
["<code>", inline(Text), "</code>"];
inline({line_break, _, _, _}) ->
"<br/>";
inline(Text) when is_list(Text) ->
[inline(T) || T <- Text].
html_encode(Text) ->
<<case C of
$& -> <<"&">>;
$< -> <<"<">>;
$> -> <<">">>;
$" -> <<""">>;
$' -> <<"'">>;
_ -> <<C/utf8>>
end || <<C/utf8>> <= Text>>.
