#!/usr/bin/env perl
# Copyright (C) 2017–2021  Alex Schroeder <alex@gnu.org>

# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, either version 3 of the License, or (at your option) any
# later version.
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see <https://www.gnu.org/licenses/>.

=encoding utf8

=head1 NAME

phoebe-ctl - admin control for a Phoebe wiki


This script helps you maintain your Phoebe installation.


=item B<--wiki_dir=>I<DIR>

This the wiki data directory to use; the default is either the value of the
C<GEMINI_WIKI_DATA_DIR> environment variable, or the C<./wiki> subdirectory. Use
it to specify a space, too.

=item B<--log=>I<NUMBER>

This is the log level to use. 1 only prints errors; 2 also prints warnings (this
is the default); 3 prints any kind of information; 4 prints all sorts of info
the developer wanted to see as they were fixing bugs.


=head2 Commands

B<phoebe-ctl help>

This is what you're reading right now.

B<phoebe-ctl update-changes>

This command looks at all the pages in the F<page> directory and generates new
entries for your changes log into F<changes.log>.

B<phoebe-ctl erase-page>

This command removes pages from the F<page> directory, removes all the kept
revisions in the F<keep> directory, and all the mentions in the F<change.log>.
Use this if spammers and vandals created page names you want to eliminate.

B<phoebe-ctl html-export> [B<--source=>F<subdirectory> ...]
[B<--target=>F<directory>] [B<--no-extension>]

This command converts all the pages in the subdirectories provided to HTML and
writes the HTML files into the target directory. The subdirectories must exist
inside your wiki data directory. The default wiki data directory is F<wiki> and
the default source subdirectory is undefined, so the actual files to be
processed are F<wiki/page/*.gmi>; if you're using virtual hosting, the
subdirectory might be your host name; if you're using spaces, those need to be
appended as well.


    phoebe-ctl html-export --wiki_dir=/home/alex/phoebe \
      --source=transjovian.org \
      --source=transjovian.org/phoebe \
      --source=transjovian.org/gemini \
      --source=transjovian.org/titan \

This will create HTML files in F</home/alex/transjovian.org>,
F</home/alex/transjovian.org/phoebe>, F</home/alex/transjovian.org/gemini>, and

Note that the I<links> in these HTML files do not include the F<.html> extension
(e.g. C</test>), so this relies on your web server doing the right thing: if a
visitor requests C</test> the web server must serve F</test.html>. If that
doesn't work, perhaps using C<--no-extension> is your best bet: the HTML files
will be written without the F<.html> extension. This should also work for local
browsing, although it does look strange, all those pages with the F<.html>

B<phoebe-ctl log hits>

If you are using L<App::Phoebe::SpeedBump>, you can find the number of blocked
requests. First, make you you are using the module in your config file:

    use App::Phoebe::DebugIpNumbers;

Make sure you start or start C<phoebe> with C<--log_level=info> or
C<--log_level=debug>. First generate a log file. Better to zip it up and analyse
it elsewhere. This can be pretty big!

    journalctl --unit=phoebe | gzip > phoebe.log.gz

Here's how to see how many requests are blocked:

    zcat phoebe.log.gz | script/phoebe-ctl log hits | head

B<phoebe-ctl log requests [IP number]>

If you are logging IP numbers, this command will offer a little summary. In your
config file, you need the following (or start C<phoebe> with

    package App::Phoebe;
    use Modern::Perl;
    our ($log);

And you need L<App::Phoebe::DebugIpNumbers>, of course:

    use App::Phoebe::DebugIpNumbers;

Example basic usage, feeding it the journal kept by C<systemd>, giving you the
most active IP numbers:

    journalctl --unit phoebe | phoebe-ctl log hits | head

Giving you a summary of the 20 most popular requests (Gopher selectors, Gemini
URLs, or web requests):

    journalctl --unit phoebe | phoebe-ctl log requests

The same, but limited to a particular IP number:

    journalctl --unit phoebe | phoebe-ctl log requests


package Gemini::Wiki::Control;
use Modern::Perl '2018';
use File::Slurper qw(read_dir read_text write_text);
use Encode qw(encode_utf8 decode_utf8);
use Getopt::Long;
use Pod::Text;
use File::Path qw(remove_tree);
use POSIX qw(round);
use utf8;

binmode(STDOUT, ":utf8");

my $log = 2;
my $dir = "./wiki";
my @sources;
my $target;
my $no_extension;
GetOptions (
  "log=i" => \$log,
  "wiki_dir=s" => \$dir,
  "source=s" => \@sources,
  "target=s" => \$target,
  "no-extension" => \$no_extension, );
@sources = ("") unless @sources;

my $subcommands = {
  "help" => 0,
  "update-changes" => \&update_changes,
  "erase-page" => \&erase_page,
  "html-export" => \&html_export,
  "log" => \&log, };

my $subcommand;
$subcommand = shift(@ARGV) if @ARGV;
die "No subcommand\n" unless $subcommand;
$subcommand = $subcommands->{$subcommand};
die "No known subcommand\n" unless defined $subcommand;
if (not $subcommand) {
  my $parser = Pod::Text->new();



sub update_changes {
  my %pages;
  my $now = time;
  $pages{decode_utf8($_)} = modified("$dir/page/$_.gmi") for map { s/\.gmi$//; $_ } grep /\.gmi$/, read_dir("$dir/page");
  say "Read " . scalar(keys %pages) . " pages" if $log >= 3;
  say join("\n", map { $_ . "\t" . $pages{$_} } sort keys %pages) if $log >= 4;
  my %files;
  $files{decode_utf8($_)} = modified("$dir/file/$_") for read_dir("$dir/file");
  say "Read " . scalar(keys %files) . " files" if $log >= 3;
  say join("\n", map { $_ . "\t" . $files{$_} } sort keys %files) if $log >= 4;
  my %revisions;
  my %changes;
  for (split /\n/, read_text "$dir/changes.log") {
    my ($ts, $id, $revision) = split(/\x1f/);
    $revisions{$id} = $revision;
    if ($revision) {
      $changes{$id} = $ts;
    } else {
      $changes{$id . "\x1c"} = $ts;
  say "Read " . scalar(keys %changes) . " changes" if $log >= 3;
  say join("\n", map { $_ . "\t" . $changes{$_} } sort keys %changes) if $log >= 4;
  open(my $fh, ">>:encoding(UTF-8)", "$dir/changes.log") or die "Cannot write $dir/changes.log: $!";
  for (keys %pages) {
    if (not $changes{$_} or $pages{$_} > $changes{$_}) {
      say "Page $_ is added to changes" if $log >= 4;
      my $revision = $revisions{$_} || 0;
      say $fh join("\x1f", $now, $_, 1 + $revision, "0000");
      utime($now, $now, "$dir/page/$_.gmi") or warn "Could not set utime for $dir/page/$_.gmi\n";
  for (keys %files) {
    if (not $changes{$_ . "\x1c"} or $files{$_} > $changes{$_ . "\x1c"}) {
      say "File $_ is added to changes" if $log >= 4;
      say $fh join("\x1f", $now, $_, 0, "0000");
      utime($now, $now, "$dir/file/$_") or warn "Could not set utime for $dir/file/$_\n";

sub modified {
  my $ts = (stat(shift))[9];
  return $ts;

sub erase_page {
  my @page = @_;
  die "You need to list the pages to erase\n" unless @page;
  for my $page (@page) {
    if (not -f "$dir/page/$page.gmi") {
      warn "$page does not exist\n";
  my $n = unlink map { "$dir/page/$_.gmi" } @page;
  warn "Deleted $n pages: $!\n" if $n < @page;
  my @dirs = grep { -d } map { "$dir/keep/$_" } @page;
  remove_tree(@dirs, { safe => 1});
  if (-f "$dir/changes.log") {
    my @log = grep {
      my ($ts, $id, $revision, $code) = split(/\x1f/);
      0 == grep { $id eq $_ } @page; # only keep log lines that are not mentioned
    } split /\n/, read_text "$dir/changes.log";
    rename("$dir/changes.log", "$dir/changes.log~")
	or die "Cannot rename $dir/changes.log to changes.log~: $!";
    write_text("$dir/changes.log", join("\n", @log));
  if (-f "$dir/index") {
    my @index = grep {
      my $id = $_;
      0 == grep { $id eq $_ } @page; # only keep index pages that are not mentioned
    } split /\n/, read_text "$dir/index";
    rename("$dir/index", "$dir/index~")
	or die "Cannot rename $dir/index to index~: $!";
    write_text("$dir/index", join("\n", @index));

sub html_export {
  die "You need to provide a target directory for the HTML files using --target=directory\n" unless $target;
  for my $source (@sources) {
    my $source_dir = "$dir$source";
    die "Source directory $source_dir does not exist\n" unless -d $source_dir;
    my $target_dir = "$target$source";
    mkdir $target_dir or die "Cannot create target directory $target_dir: $!\n"
	unless -d $target_dir;
    for my $page (map { s/\.gmi$//; $_ } grep /\.gmi$/, read_dir("$source_dir/page")) {
      my $id = decode_utf8 $page;
      my $text = read_text "$source_dir/page/$page.gmi"; # fatal if it does not exist
      say "Converting $id";
      my $filename = "$target_dir/$page";
      $filename .= ".html" unless $no_extension;
      open(my $fh, ">:utf8", $filename)
	  or die "Cannot write $filename: $!\n";
      say $fh "<!DOCTYPE html>";
      say $fh "<html>";
      say $fh "<head>";
      say $fh "<meta charset=\"utf-8\">";
      say $fh "<title>" . quote_html($id) . "</title>";
      say $fh "<link type=\"text/css\" rel=\"stylesheet\" href=\"/default.css\"/>";
      say $fh "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">";
      say $fh "</head>";
      say $fh "<body>";
      say $fh "<h1>" . quote_html($id) . "</h1>";
      say $fh to_html($text);
      # skipping footers
      say $fh "</body>";
      say $fh "</html>";

sub quote_html {
  my $html = shift;
  $html =~ s/&/&amp;/g;
  $html =~ s/</&lt;/g;
  $html =~ s/>/&gt;/g;
  $html =~ s/[\x00-\x08\x0b\x0c\x0e-\x1f]/ /g; # legal xml: #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]
  return $html;

# returns lines!
sub to_html {
  my $text = shift;
  my @lines;
  my $list;
  my $code;
  for (split /\n/, quote_html($text)) {
    if (/^```(?:type=([a-z]+))?/) {
      my $type = $1||"default";
      if ($code) {
	push @lines, "</pre>";
	$code = 0;
      } else {
	push @lines, "</ul>" if $list;
	$list = 0;
	push @lines, "<pre class=\"$type\">";
	$code = 1;
    } elsif ($code) {
      push @lines, $_;
    } elsif (/^\* +(.*)/) {
      push @lines, "<ul>" unless $list;
      push @lines, "<li>$1";
      $list = 1;
    } elsif (my ($url, $text) = /^=&gt;\s*(\S+)\s*(.*)/) { # quoted HTML!
      push @lines, "<ul>" unless $list;
      $text ||= $url;
      push @lines, "<li><a href=\"$url\">$text</a>";
      $list = 1;
    } elsif (/^(#{1,6})\s*(.*)/) {
      push @lines, "</ul>" if $list;
      $list = 0;
      my $level = length($1);
      push @lines, "<h$level>$2</h$level>";
    } elsif (/^&gt;\s*(.*)/) { # quoted HTML!
      push @lines, "</ul>" if $list;
      $list = 0;
      push @lines, "<blockquote>$1</blockquote>";
    } else {
      push @lines, "</ul>" if $list;
      $list = 0;
      push @lines, "<p>$_";
  push @lines, "</pre>" if $code;
  push @lines, "</ul>" if $list;
  return join("\n", @lines);

sub log {
  my ($type, $filter) = @ARGV;
  if (not $type or $type ne "hits" and $type ne "requests") {
    die "No known log type (one of: hits, requests)\n";
  my ($ip, %ip, %block, $n, $blocks, %request);
  while (<STDIN>) {
    if (/\[debug\] Visitor: (\S+)$/) {
      $ip = $1;
    } elsif ((not $filter or $ip and $filter eq $ip) and /\[info\] Looking at (.*)/) {
      $ip //= "anon";
    } elsif ($ip and (not $filter or $filter eq $ip) and /\[info\] (Net range (\S+) is blocked|IP is blocked)/) {
  die("No hits (you must run the server on --log_level=info or --log_level=debug\n") unless $n;
  say("Total hits:   $n");
  say("Total blocks: $blocks");
  say("Bot level:    " . round($blocks / $n * 100) . "%") if $blocks;
  say("-" x length("Total blocks: $blocks"));
  if ($type eq "hits") {
    printf("%5s %4s%% %5s %s\n", "Hits", "Hits", "Block", "IP Number");
    for (sort { $ip{$b} <=> $ip{$a} } keys %ip) {
      printf("%5d %4d%% %4d%% %s\n", $ip{$_}, int(100*$ip{$_}/$n), exists $block{$_} ? int(100*$block{$_}/$n) : 0, $_);
  } elsif ($type eq "requests") {
    printf("%5s %4s%% %s\n", "Hits", "Hits", "Request");
    for (sort { $request{$b} <=> $request{$a} } keys %request) {
      printf("%5d %4d%% %s\n", $request{$_}, int(100*$request{$_}/$n), $_);