!/usr/bin/env perl

use strict;

use warnings;

use v5.10;

use String::ShellQuote qw( shell_quote );

use Any::URI::Escape qw( uri_escape );

my $path = $ENV{'PATH_INFO'};

my $query = $ENV{'QUERY_STRING'};

my $script_path = $ENV{'SCRIPT_NAME'};

sub reply {

my ($code, $meta) = @_;

print "$code $meta\r\n";

if ($code != 20) {

	exit(0);

}

}

sub banner {

say '# man';

say '';

}

sub do_search {

my ($query) = @_;

reply(20, 'text/gemini');

banner;

say "Search results for: $query";

my $some = 0;

open(my $h, "-|", ("apropos", "-w", $query));

foreach (<$h>) {

	chomp;

	s,^.*/,,;

	my ($page, $section) = split /\./;

	my $esc = uri_escape($page);

	say "=> $script_path/$section/$esc $page($section)";

	$some = 1;

}

close($h);

if (!$some) {

	say "Nothing.";

}

}

sub man_cmd {

my ($a, $b) = @_;

if (!$b) {

	return shell_quote($a);

}

return shell_quote($a) . " " . shell_quote($b);

}

sub view_man {

my $args = @_;

reply(20, 'text/plain');

say "% man ", join(' ', @_);

my $pid;

if (!defined($pid = fork())) {

	die();

} elsif ($pid == 0) {

	exec("man -Tutf8 -- " . man_cmd(@_) .

	     " | col -b");

}

waitpid($pid, 0);

}

my $home = !$path || $path eq '/';

if ($home && $query) {

do_search($query);

} elsif ($home) {

reply(20, 'text/gemini');

banner;

say "Welcome to the manual!";

say "";

say "This service allows you to lookup a manual page is several ways:";

say "* by name, appending /<name> to the current URL";

say "* by name and section, appending /<section>/<name> to the current URL";

say "* by searching it, appending ?<query> to the current URL";

say "";

say "=> $script_path/search Or just click here to search";

} elsif ($path =~ m[^/?search/?]) {

if (!$query) {

	reply(10, 'manpage:');

}

do_search($query);

} elsif ($path =~ m{^/([1-9]p?)/([-\w:]+)/?$}) {

view_man($1, $2);

} elsif ($path =~ m[^/([\w:]+)/?$]) {

view_man($1);

} else {

reply(51, 'not found');

}