1 #!/usr/bin/env perl
2 #
3 # Copyright (c) 2022 Omar Polo <op@openbsd.org>
4 #
5 # Permission to use, copy, modify, and distribute this software for any
6 # purpose with or without fee is hereby granted, provided that the above
7 # copyright notice and this permission notice appear in all copies.
8 #
9 # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 
17 use v5.10;
18 use strict;
19 use warnings;
20 
21 my $in_pre = 0;
22 my $in_list = 0;
23 
24 while (<>) {
25 	chomp;
26 	if ($in_pre && m/^```/) {
27 		$in_pre = 0;
28 		say "</pre>";
29 	} elsif (!$in_pre && m/^```/) {
30 		if ($in_list) {
31 			$in_list = 0;
32 			say "</ul>";
33 		}
34 		$in_pre = 1;
35 		print "<pre>";
36 	} elsif ($in_pre) {
37 		say san($_);
38 	} elsif ($in_list && m/^$/) {
39 		say "</ul>";
40 		$in_list = 0;
41 	} elsif (m/^\*\s+(.*)/) { # NB: at least one space
42 		if (!$in_list) {
43 			$in_list = "item";
44 			say "<ul>";
45 		} elsif ($in_list eq "link") {
46 			$in_list = "item";
47 			say "</ul>";
48 			say "<ul>";
49 		}
50 		output("li", $1);
51 	} elsif (m/^=>\s*([^\s]*)\s*(.*)$/) {
52 		if (!$in_list) {
53 			$in_list = "link";
54 			say "<ul class='link-list'>";
55 		} elsif ($in_list eq "item") {
56 			$in_list = "link";
57 			say "</ul>";
58 			say "<ul class='link-list'>";
59 		}
60 		my $href = $1;
61 		$_ = $2 || $1;
62 		say "<li><a href='$href'>". san() ."</a></li>";
63 	} elsif (m/^###\s*(.*)$/) {
64 		output("h3", $1);
65 	} elsif (m/^##\s*(.*)$/) {
66 		output("h2", $1);
67 	} elsif (m/^#\s*(.*)$/) {
68 		output("h1", $1);
69 	} elsif (m/^>\s*(.*)$/) {
70 		output("blockquote", $1);
71 	} else {
72 		output("p", $_);
73 	}
74 }
75 
76 sub san {
77 	s/&/\&amp;/g;
78 	s/</\&lt;/g;
79 	s/>/\&gt;/g;
80 	return $_;
81 }
82 
83 sub output {
84 	my ($tn, $content) = @_;
85 
86 	if (!$in_list && $tn eq "li") {
87 		$in_list = 1;
88 		say "<ul>";
89 	}
90 
91 	if ($in_list && $tn ne "li") {
92 		$in_list = 0;
93 		say "</ul>";
94 	}
95 
96 	if ($tn eq "p" && $content eq "") {
97 		return;
98 	}
99 
100 	$_ = $content;
101 	say "<$tn>". san() ."</$tn>";
102 }