X-Git-Url: https://git.sesse.net/?p=remoteglot;a=blobdiff_plain;f=remoteglot.pl;h=9cbf820d5dcd336d5e0bff16d118da711462e84f;hp=53d5cab390fca0d907ea732639b1924b9a63c832;hb=94f448c82ea3da610c8aca0030f977d1f54741d6;hpb=68ae519ca55030ec4ee02d3db69fe1368f1737e9

diff --git a/remoteglot.pl b/remoteglot.pl
index 53d5cab..9cbf820 100755
--- a/remoteglot.pl
+++ b/remoteglot.pl
@@ -5,39 +5,46 @@
 #              analysis, or for live analysis of relayed games. (Do not use for
 #              cheating! Cheating is bad for your karma, and your abuser flag.)
 #
-# Copyright 2007 Steinar H. Gunderson <sgunderson@bigfoot.com>
+# Copyright 2007 Steinar H. Gunderson <steinar+remoteglot@gunderson.no>
 # Licensed under the GNU General Public License, version 2.
 #
 
+use AnyEvent;
+use AnyEvent::Handle;
+use AnyEvent::HTTP;
+use Chess::PGN::Parse;
+use EV;
 use Net::Telnet;
-use FileHandle;
+use File::Slurp;
 use IPC::Open2;
 use Time::HiRes;
 use JSON::XS;
+use URI::Escape;
+use DBI;
+use DBD::Pg;
+require 'Position.pm';
+require 'Engine.pm';
+require 'config.pm';
 use strict;
 use warnings;
-
-# Configuration
-my $server = "freechess.org";
-my $target = "GMCarlsen";
-my $engine_cmdline = "'./Deep Rybka 4 SSE42 x64'";
-my $engine2_cmdline = "./stockfish_13111119_x64_modern_sse42";
-my $telltarget = undef;   # undef to be silent
-my @tell_intervals = (5, 20, 60, 120, 240, 480, 960);  # after each move
-my $uci_assume_full_compliance = 0;                    # dangerous :-)
-my $update_max_interval = 2.0;
-my $second_engine_start_depth = 8;
-my @masters = (
-	'Sesse',
-	'Sessse',
-	'Sesssse',
-	'greatestguns',
-	'beuki'
-);
+no warnings qw(once);
 
 # Program starts here
-$SIG{ALRM} = sub { output(); };
 my $latest_update = undef;
+my $output_timer = undef;
+my $http_timer = undef;
+my $stop_pgn_fetch = 0;
+my $tb_retry_timer = undef;
+my %tb_cache = ();
+my $tb_lookup_running = 0;
+my $last_written_json = undef;
+
+# Persisted so we can restart.
+# TODO: Figure out an appropriate way to deal with database restarts
+# and/or Postgres going away entirely.
+my $dbh = DBI->connect($remoteglotconf::dbistr, $remoteglotconf::dbiuser, $remoteglotconf::dbipass)
+	or die DBI->errstr;
+$dbh->{RaiseError} = 1;
 
 $| = 1;
 
@@ -52,168 +59,89 @@ open(UCILOG, ">ucilog.txt")
 print UCILOG "Log starting.\n";
 select(UCILOG);
 $| = 1;
+
+open(TBLOG, ">tblog.txt")
+	or die "tblog.txt: $!";
+print TBLOG "Log starting.\n";
+select(TBLOG);
+$| = 1;
+
 select(STDOUT);
+umask 0022;  # analysis.json should not be served to users.
 
 # open the chess engine
-my $engine = open_engine($engine_cmdline, 'E1');
-my $engine2 = open_engine($engine2_cmdline, 'E2');
-my ($last_move, $last_tell);
+my $engine = open_engine($remoteglotconf::engine_cmdline, 'E1', sub { handle_uci(@_, 1); });
+my $engine2 = open_engine($remoteglotconf::engine2_cmdline, 'E2', sub { handle_uci(@_, 0); });
+my $last_move;
 my $last_text = '';
-my $last_told_text = '';
 my ($pos_waiting, $pos_calculating, $pos_calculating_second_engine);
 
 uciprint($engine, "setoption name UCI_AnalyseMode value true");
-# uciprint($engine, "setoption name NalimovPath value /srv/tablebase");
-uciprint($engine, "setoption name NalimovUsage value Rarely");
-uciprint($engine, "setoption name Hash value 1024");
-# uciprint($engine, "setoption name MultiPV value 2");
+while (my ($key, $value) = each %remoteglotconf::engine_config) {
+	uciprint($engine, "setoption name $key value $value");
+}
 uciprint($engine, "ucinewgame");
 
-uciprint($engine2, "setoption name UCI_AnalyseMode value true");
-# uciprint($engine2, "setoption name NalimovPath value /srv/tablebase");
-uciprint($engine2, "setoption name NalimovUsage value Rarely");
-uciprint($engine2, "setoption name Hash value 1024");
-uciprint($engine2, "setoption name Threads value 8");
-uciprint($engine2, "setoption name MultiPV value 500");
-uciprint($engine2, "ucinewgame");
+if (defined($engine2)) {
+	uciprint($engine2, "setoption name UCI_AnalyseMode value true");
+	while (my ($key, $value) = each %remoteglotconf::engine2_config) {
+		uciprint($engine2, "setoption name $key value $value");
+	}
+	uciprint($engine2, "setoption name MultiPV value 500");
+	uciprint($engine2, "ucinewgame");
+}
 
 print "Chess engine ready.\n";
 
 # now talk to FICS
-my $t = Net::Telnet->new(Timeout => 10, Prompt => '/fics% /');
-$t->input_log(\*FICSLOG);
-$t->open($server);
-$t->print("SesseBOT");
-$t->waitfor('/Press return to enter the server/');
-$t->cmd("");
-
-# set some options
-$t->cmd("set shout 0");
-$t->cmd("set seek 0");
-$t->cmd("set style 12");
-$t->cmd("observe $target");
-
-# main loop
-print "FICS ready.\n";
-while (1) {
-	my $rin = '';
-	my $rout;
-	vec($rin, fileno($engine->{'read'}), 1) = 1;
-	vec($rin, fileno($engine2->{'read'}), 1) = 1;
-	vec($rin, fileno($t), 1) = 1;
-
-	my ($nfound, $timeleft) = select($rout=$rin, undef, undef, 5.0);
-	my $sleep = 1.0;
-
-	while (1) {
-		my $line = $t->getline(Timeout => 0, errmode => 'return');
-		last if (!defined($line));
-
-		chomp $line;
-		$line =~ tr/\r//d;
-		if ($line =~ /^<12> /) {
-			my $pos = style12_to_pos($line);
-			
-			# if this is already in the queue, ignore it
-			next if (defined($pos_waiting) && $pos->{'fen'} eq $pos_waiting->{'fen'});
-
-			# if we're already chewing on this and there's nothing else in the queue,
-			# also ignore it
-			next if (!defined($pos_waiting) && defined($pos_calculating) &&
-			         $pos->{'fen'} eq $pos_calculating->{'fen'});
-
-			# if we're already thinking on something, stop and wait for the engine
-			# to approve
-			if (defined($pos_calculating)) {
-				if (!defined($pos_waiting)) {
-					uciprint($engine, "stop");
-				}
-				if ($uci_assume_full_compliance) {
-					$pos_waiting = $pos;
-				} else {
-					uciprint($engine, "position fen " . $pos->{'fen'});
-					uciprint($engine, "go infinite");
-					$pos_calculating = $pos;
-				}
-			} else {
-				# it's wrong just to give the FEN (the move history is useful,
-				# and per the UCI spec, we should really have sent "ucinewgame"),
-				# but it's easier
-				uciprint($engine, "position fen " . $pos->{'fen'});
-				uciprint($engine, "go infinite");
-				$pos_calculating = $pos;
+my ($t, $ev1);
+if (defined($remoteglotconf::server)) {
+	$t = Net::Telnet->new(Timeout => 10, Prompt => '/fics% /');
+	$t->input_log(\*FICSLOG);
+	$t->open($remoteglotconf::server);
+	$t->print($remoteglotconf::nick);
+	$t->waitfor('/Press return to enter the server/');
+	$t->cmd("");
+
+	# set some options
+	$t->cmd("set shout 0");
+	$t->cmd("set seek 0");
+	$t->cmd("set style 12");
+
+	$ev1 = AnyEvent->io(
+		fh => fileno($t),
+		poll => 'r',
+		cb => sub {    # what callback to execute
+			while (1) {
+				my $line = $t->getline(Timeout => 0, errmode => 'return');
+				return if (!defined($line));
+
+				chomp $line;
+				$line =~ tr/\r//d;
+				handle_fics($line);
 			}
-
-			if (defined($pos_calculating_second_engine)) {
-				uciprint($engine2, "stop");
-			} else {
-				uciprint($engine2, "position fen " . $pos->{'fen'});
-				uciprint($engine2, "go infinite");
-				$pos_calculating_second_engine = $pos;
-			}
-
-			$engine->{'info'} = {};
-			$engine2->{'info'} = {};
-			$last_move = time;
-
-			# 
-			# Output a command every move to note that we're
-			# still paying attention -- this is a good tradeoff,
-			# since if no move has happened in the last half
-			# hour, the analysis/relay has most likely stopped
-			# and we should stop hogging server resources.
-			#
-			$t->cmd("date");
-		}
-		if ($line =~ /^([A-Za-z]+)(?:\([A-Z]+\))* tells you: (.*)$/) {
-			my ($who, $msg) = ($1, $2);
-
-			next if (grep { $_ eq $who } (@masters) == 0);
-	
-			if ($msg =~ /^fics (.*?)$/) {
-				$t->cmd("tell $who Executing '$1' on FICS.");
-				$t->cmd($1);
-			} elsif ($msg =~ /^uci (.*?)$/) {
-				$t->cmd("tell $who Sending '$1' to the engine.");
-				print { $engine->{'write'} } "$1\n";
-			} else {
-				$t->cmd("tell $who Couldn't understand '$msg', sorry.");
-			}
-		}
-		#print "FICS: [$line]\n";
-		$sleep = 0;
-	}
-	
-	# any fun on the UCI channel?
-	if ($nfound > 0 && vec($rout, fileno($engine->{'read'}), 1) == 1) {
-		my @lines = read_lines($engine);
-		for my $line (@lines) {
-			next if $line =~ /(upper|lower)bound/;
-			handle_uci($engine, $line, 1);
 		}
-		$sleep = 0;
-
-		output();
-	}
-	if ($nfound > 0 && vec($rout, fileno($engine2->{'read'}), 1) == 1) {
-		my @lines = read_lines($engine2);
-		for my $line (@lines) {
-			next if $line =~ /(upper|lower)bound/;
-			handle_uci($engine2, $line, 0);
-		}
-		$sleep = 0;
-
-		output();
+	);
+}
+if (defined($remoteglotconf::target)) {
+	if ($remoteglotconf::target =~ /^https?:/) {
+		fetch_pgn($remoteglotconf::target);
+	} elsif (defined($t)) {
+		$t->cmd("observe $remoteglotconf::target");
 	}
-
-	sleep $sleep;
 }
+if (defined($t)) {
+	print "FICS ready.\n";
+}
+
+# Engine events have already been set up by Engine.pm.
+EV::run;
 
 sub handle_uci {
 	my ($engine, $line, $primary) = @_;
 
-	chomp $line;
-	$line =~ tr/\r//d;
+	return if $line =~ /(upper|lower)bound/;
+
 	$line =~ s/  / /g;  # Sometimes needed for Zappa Mexico
 	print UCILOG localtime() . " $engine->{'tag'} <= $line\n";
 	if ($line =~ /^info/) {
@@ -230,9 +158,9 @@ sub handle_uci {
 	}
 	if ($line =~ /^bestmove/) {
 		if ($primary) {
-			return if (!$uci_assume_full_compliance);
+			return if (!$remoteglotconf::uci_assume_full_compliance);
 			if (defined($pos_waiting)) {
-				uciprint($engine, "position fen " . $pos_waiting->{'fen'});
+				uciprint($engine, "position fen " . $pos_waiting->fen());
 				uciprint($engine, "go infinite");
 
 				$pos_calculating = $pos_waiting;
@@ -241,11 +169,268 @@ sub handle_uci {
 		} else {
 			$engine2->{'info'} = {};
 			my $pos = $pos_waiting // $pos_calculating;
-			uciprint($engine2, "position fen " . $pos->{'fen'});
+			uciprint($engine2, "position fen " . $pos->fen());
 			uciprint($engine2, "go infinite");
 			$pos_calculating_second_engine = $pos;
 		}
 	}
+	output();
+}
+
+my $getting_movelist = 0;
+my $pos_for_movelist = undef;
+my @uci_movelist = ();
+my @pretty_movelist = ();
+
+sub handle_fics {
+	my $line = shift;
+	if ($line =~ /^<12> /) {
+		handle_position(Position->new($line));
+		$t->cmd("moves");
+	}
+	if ($line =~ /^Movelist for game /) {
+		my $pos = $pos_waiting // $pos_calculating;
+		if (defined($pos)) {
+			@uci_movelist = ();
+			@pretty_movelist = ();
+			$pos_for_movelist = Position->start_pos($pos->{'player_w'}, $pos->{'player_b'});
+			$getting_movelist = 1;
+		}
+	}
+	if ($getting_movelist &&
+	    $line =~ /^\s* \d+\. \s+                     # move number
+                       (\S+) \s+ \( [\d:.]+ \) \s*       # first move, then time
+	               (?: (\S+) \s+ \( [\d:.]+ \) )?    # second move, then time 
+	             /x) {
+		eval {
+			my $uci_move;
+			($pos_for_movelist, $uci_move) = $pos_for_movelist->make_pretty_move($1);
+			push @uci_movelist, $uci_move;
+			push @pretty_movelist, $1;
+
+			if (defined($2)) {
+				($pos_for_movelist, $uci_move) = $pos_for_movelist->make_pretty_move($2);
+				push @uci_movelist, $uci_move;
+				push @pretty_movelist, $2;
+			}
+		};
+		if ($@) {
+			warn "Error when getting FICS move history: $@";
+			$getting_movelist = 0;
+		}
+	}
+	if ($getting_movelist &&
+	    $line =~ /^\s+ \{.*\} \s+ (?: \* | 1\/2-1\/2 | 0-1 | 1-0 )/x) {
+		# End of movelist.
+		for my $pos ($pos_waiting, $pos_calculating) {
+			next if (!defined($pos));
+			if ($pos->fen() eq $pos_for_movelist->fen()) {
+				$pos->{'history'} = \@pretty_movelist;
+			}
+		}
+		$getting_movelist = 0;
+	}
+	if ($line =~ /^([A-Za-z]+)(?:\([A-Z]+\))* tells you: (.*)$/) {
+		my ($who, $msg) = ($1, $2);
+
+		next if (grep { $_ eq $who } (@remoteglotconf::masters) == 0);
+
+		if ($msg =~ /^fics (.*?)$/) {
+			$t->cmd("tell $who Executing '$1' on FICS.");
+			$t->cmd($1);
+		} elsif ($msg =~ /^uci (.*?)$/) {
+			$t->cmd("tell $who Sending '$1' to the engine.");
+			print { $engine->{'write'} } "$1\n";
+		} elsif ($msg =~ /^pgn (.*?)$/) {
+			my $url = $1;
+			$t->cmd("tell $who Starting to poll '$url'.");
+			fetch_pgn($url);
+		} elsif ($msg =~ /^stoppgn$/) {
+			$t->cmd("tell $who Stopping poll.");
+			$stop_pgn_fetch = 1;
+			$http_timer = undef;
+		} elsif ($msg =~ /^quit$/) {
+			$t->cmd("tell $who Bye bye.");
+			exit;
+		} else {
+			$t->cmd("tell $who Couldn't understand '$msg', sorry.");
+		}
+	}
+	#print "FICS: [$line]\n";
+}
+
+# Starts periodic fetching of PGNs from the given URL.
+sub fetch_pgn {
+	my ($url) = @_;
+	AnyEvent::HTTP::http_get($url, sub {
+		handle_pgn(@_, $url);
+	});
+}
+
+my ($last_pgn_white, $last_pgn_black);
+my @last_pgn_uci_moves = ();
+my $pgn_hysteresis_counter = 0;
+
+sub handle_pgn {
+	my ($body, $header, $url) = @_;
+
+	if ($stop_pgn_fetch) {
+		$stop_pgn_fetch = 0;
+		$http_timer = undef;
+		return;
+	}
+
+	my $pgn = Chess::PGN::Parse->new(undef, $body);
+	if (!defined($pgn)) {
+		warn "Error in parsing PGN from $url [body='$body']\n";
+	} elsif (!$pgn->read_game()) {
+		warn "Error in reading PGN game from $url [body='$body']\n";
+	} elsif ($body !~ /^\[/) {
+		warn "Malformed PGN from $url [body='$body']\n";
+	} else {
+		eval {
+			# Skip to the right game.
+			while (defined($remoteglotconf::pgn_filter) &&
+			       !&$remoteglotconf::pgn_filter($pgn)) {
+				$pgn->read_game() or die "Out of games during filtering";
+			}
+
+			$pgn->parse_game({ save_comments => 'yes' });
+			my $white = $pgn->white;
+			my $black = $pgn->black;
+			$white =~ s/,.*//;  # Remove first name.
+			$black =~ s/,.*//;  # Remove first name.
+			my $pos = Position->start_pos($white, $black);
+			my $moves = $pgn->moves;
+			my @uci_moves = ();
+			my @repretty_moves = ();
+			for my $move (@$moves) {
+				my ($npos, $uci_move) = $pos->make_pretty_move($move);
+				push @uci_moves, $uci_move;
+
+				# Re-prettyprint the move.
+				my ($from_row, $from_col, $to_row, $to_col, $promo) = parse_uci_move($uci_move);
+				my ($pretty, undef) = $pos->{'board'}->prettyprint_move($from_row, $from_col, $to_row, $to_col, $promo);
+				push @repretty_moves, $pretty;
+				$pos = $npos;
+			}
+			if ($pgn->result eq '1-0' || $pgn->result eq '1/2-1/2' || $pgn->result eq '0-1') {
+				$pos->{'result'} = $pgn->result;
+			}
+			$pos->{'history'} = \@repretty_moves;
+
+			extract_clock($pgn, $pos);
+
+			# Sometimes, PGNs lose a move or two for a short while,
+			# or people push out new ones non-atomically. 
+			# Thus, if we PGN doesn't change names but becomes
+			# shorter, we mistrust it for a few seconds.
+			my $trust_pgn = 1;
+			if (defined($last_pgn_white) && defined($last_pgn_black) &&
+			    $last_pgn_white eq $pgn->white &&
+			    $last_pgn_black eq $pgn->black &&
+			    scalar(@uci_moves) < scalar(@last_pgn_uci_moves)) {
+				if (++$pgn_hysteresis_counter < 3) {
+					$trust_pgn = 0;	
+				}
+			}
+			if ($trust_pgn) {
+				$last_pgn_white = $pgn->white;
+				$last_pgn_black = $pgn->black;
+				@last_pgn_uci_moves = @uci_moves;
+				$pgn_hysteresis_counter = 0;
+				handle_position($pos);
+			}
+		};
+		if ($@) {
+			warn "Error in parsing moves from $url: $@\n";
+		}
+	}
+	
+	$http_timer = AnyEvent->timer(after => 1.0, cb => sub {
+		fetch_pgn($url);
+	});
+}
+
+sub handle_position {
+	my ($pos) = @_;
+	find_clock_start($pos, $pos_calculating);
+		
+	# if this is already in the queue, ignore it (just update the result)
+	if (defined($pos_waiting) && $pos->fen() eq $pos_waiting->fen()) {
+		$pos_waiting->{'result'} = $pos->{'result'};
+		return;
+	}
+
+	# if we're already chewing on this and there's nothing else in the queue,
+	# also ignore it
+	if (!defined($pos_waiting) && defined($pos_calculating) &&
+	    $pos->fen() eq $pos_calculating->fen()) {
+		$pos_calculating->{'result'} = $pos->{'result'};
+		return;
+	}
+
+	# if we're already thinking on something, stop and wait for the engine
+	# to approve
+	if (defined($pos_calculating)) {
+		# Store the final data we have for this position in the history,
+		# with the precise clock information we just got from the new
+		# position. (Historic positions store the clock at the end of
+		# the position.)
+		#
+		# Do not output anything new to the main analysis; that's
+		# going to be obsolete really soon.
+		$pos_calculating->{'white_clock'} = $pos->{'white_clock'};
+		$pos_calculating->{'black_clock'} = $pos->{'black_clock'};
+		delete $pos_calculating->{'white_clock_target'};
+		delete $pos_calculating->{'black_clock_target'};
+		output_json(1);
+
+		if (!defined($pos_waiting)) {
+			uciprint($engine, "stop");
+		}
+		if ($remoteglotconf::uci_assume_full_compliance) {
+			$pos_waiting = $pos;
+		} else {
+			uciprint($engine, "position fen " . $pos->fen());
+			uciprint($engine, "go infinite");
+			$pos_calculating = $pos;
+		}
+	} else {
+		# it's wrong just to give the FEN (the move history is useful,
+		# and per the UCI spec, we should really have sent "ucinewgame"),
+		# but it's easier
+		uciprint($engine, "position fen " . $pos->fen());
+		uciprint($engine, "go infinite");
+		$pos_calculating = $pos;
+	}
+
+	if (defined($engine2)) {
+		if (defined($pos_calculating_second_engine)) {
+			uciprint($engine2, "stop");
+		} else {
+			uciprint($engine2, "position fen " . $pos->fen());
+			uciprint($engine2, "go infinite");
+			$pos_calculating_second_engine = $pos;
+		}
+		$engine2->{'info'} = {};
+	}
+
+	$engine->{'info'} = {};
+	$last_move = time;
+
+	schedule_tb_lookup();
+
+	# 
+	# Output a command every move to note that we're
+	# still paying attention -- this is a good tradeoff,
+	# since if no move has happened in the last half
+	# hour, the analysis/relay has most likely stopped
+	# and we should stop hogging server resources.
+	#
+	if (defined($t)) {
+		$t->cmd("date");
+	}
 }
 
 sub parse_infos {
@@ -256,26 +441,28 @@ sub parse_infos {
 
 	# Search for "multipv" first of all, since e.g. Stockfish doesn't put it first.
 	for my $i (0..$#x - 1) {
-		if ($x[$i] =~ 'multipv') {
+		if ($x[$i] eq 'multipv') {
 			$mpv = $x[$i + 1];
 			next;
 		}
 	}
 
 	while (scalar @x > 0) {
-		if ($x[0] =~ 'multipv') {
+		if ($x[0] eq 'multipv') {
 			# Dealt with above
 			shift @x;
 			shift @x;
 			next;
 		}
-		if ($x[0] =~ /^(currmove|currmovenumber|cpuload)$/) {
+		if ($x[0] eq 'currmove' || $x[0] eq 'currmovenumber' || $x[0] eq 'cpuload') {
 			my $key = shift @x;
 			my $value = shift @x;
 			$info->{$key} = $value;
 			next;
 		}
-		if ($x[0] =~ /^(depth|seldepth|hashfull|time|nodes|nps|tbhits)$/) {
+		if ($x[0] eq 'depth' || $x[0] eq 'seldepth' || $x[0] eq 'hashfull' ||
+		    $x[0] eq 'time' || $x[0] eq 'nodes' || $x[0] eq 'nps' ||
+		    $x[0] eq 'tbhits') {
 			my $key = shift @x;
 			my $value = shift @x;
 			$info->{$key . $mpv} = $value;
@@ -287,7 +474,7 @@ sub parse_infos {
 			delete $info->{'score_cp' . $mpv};
 			delete $info->{'score_mate' . $mpv};
 
-			while ($x[0] =~ /^(cp|mate|lowerbound|upperbound)$/) {
+			while ($x[0] eq 'cp' || $x[0] eq 'mate') {
 				if ($x[0] eq 'cp') {
 					shift @x;
 					$info->{'score_cp' . $mpv} = shift @x;
@@ -319,10 +506,9 @@ sub parse_ids {
 	my ($engine, @x) = @_;
 
 	while (scalar @x > 0) {
-		if ($x[0] =~ /^(name|author)$/) {
-			my $key = shift @x;
+		if ($x[0] eq 'name') {
 			my $value = join(' ', @x);
-			$engine->{'id'}{$key} = $value;
+			$engine->{'id'}{'author'} = $value;
 			last;
 		}
 
@@ -331,190 +517,7 @@ sub parse_ids {
 	}
 }
 
-sub style12_to_pos {
-	my $str = shift;
-	my %pos = ();
-	my (@x) = split / /, $str;
-	
-	$pos{'board'} = [ @x[1..8] ];
-	$pos{'toplay'} = $x[9];
-	$pos{'ep_file_num'} = $x[10];
-	$pos{'white_castle_k'} = $x[11];
-	$pos{'white_castle_q'} = $x[12];
-	$pos{'black_castle_k'} = $x[13];
-	$pos{'black_castle_q'} = $x[14];
-	$pos{'time_to_100move_rule'} = $x[15];
-	$pos{'move_num'} = $x[26];
-	if ($x[27] =~ /([a-h][1-8])-([a-h][1-8])/) {
-		$pos{'last_move_uci'} = $1 . $2;
-	} else {
-		$pos{'last_move_uci'} = undef;
-	}
-	$pos{'last_move'} = $x[29];
-	$pos{'fen'} = make_fen(\%pos);
-
-	return \%pos;
-}
-
-sub make_fen {
-	my $pos = shift;
-
-	# the board itself
-	my (@board) = @{$pos->{'board'}};
-	for my $rank (0..7) {
-		$board[$rank] =~ s/(-+)/length($1)/ge;
-	}
-	my $fen = join('/', @board);
-
-	# white/black to move
-	$fen .= " ";
-	$fen .= lc($pos->{'toplay'});
-
-	# castling
-	my $castling = "";
-	$castling .= "K" if ($pos->{'white_castle_k'} == 1);
-	$castling .= "Q" if ($pos->{'white_castle_q'} == 1);
-	$castling .= "k" if ($pos->{'black_castle_k'} == 1);
-	$castling .= "q" if ($pos->{'black_castle_q'} == 1);
-	$castling = "-" if ($castling eq "");
-	# $castling = "-"; # chess960
-	$fen .= " ";
-	$fen .= $castling;
-
-	# en passant
-	my $ep = "-";
-	if ($pos->{'ep_file_num'} != -1) {
-		my $col = $pos->{'ep_file_num'};
-		my $nep = (qw(a b c d e f g h))[$col];
-
-		if ($pos->{'toplay'} eq 'B') {
-			$nep .= "3";
-		} else {
-			$nep .= "6";
-		}
-
-		#
-		# Showing the en passant square when actually no capture can be made
-		# seems to confuse at least Rybka. Thus, check if there's actually
-		# a pawn of the opposite side that can do the en passant move, and if
-		# not, just lie -- it doesn't matter anyway. I'm unsure what's the
-		# "right" thing as per the standard, though.
-		#
-		if ($pos->{'toplay'} eq 'B') {
-			$ep = $nep if ($col > 0 && substr($pos->{'board'}[4], $col-1, 1) eq 'p');
-			$ep = $nep if ($col < 7 && substr($pos->{'board'}[4], $col+1, 1) eq 'p');
-		} else {
-			$ep = $nep if ($col > 0 && substr($pos->{'board'}[3], $col-1, 1) eq 'P');
-			$ep = $nep if ($col < 7 && substr($pos->{'board'}[3], $col+1, 1) eq 'P');
-		}
-	}
-	$fen .= " ";
-	$fen .= $ep;
-
-	# half-move clock
-	$fen .= " ";
-	$fen .= $pos->{'time_to_100move_rule'};
-
-	# full-move clock
-	$fen .= " ";
-	$fen .= $pos->{'move_num'};
-
-	return $fen;
-}
-
-sub make_move {
-	my ($board, $from_row, $from_col, $to_row, $to_col, $promo) = @_;
-	my $move = move_to_uci_notation($from_row, $from_col, $to_row, $to_col, $promo);
-	my $piece = substr($board->[$from_row], $from_col, 1);
-	my @nb = @$board;
-
-	if ($piece eq '-') {
-		die "Invalid move $move";
-	}
-
-	# white short castling
-	if ($move eq 'e1g1' && $piece eq 'K') {
-		# king
-		substr($nb[7], 4, 1, '-');
-		substr($nb[7], 6, 1, $piece);
-		
-		# rook
-		substr($nb[7], 7, 1, '-');
-		substr($nb[7], 5, 1, 'R');
-				
-		return \@nb;
-	}
-
-	# white long castling
-	if ($move eq 'e1c1' && $piece eq 'K') {
-		# king
-		substr($nb[7], 4, 1, '-');
-		substr($nb[7], 2, 1, $piece);
-		
-		# rook
-		substr($nb[7], 0, 1, '-');
-		substr($nb[7], 3, 1, 'R');
-				
-		return \@nb;
-	}
-
-	# black short castling
-	if ($move eq 'e8g8' && $piece eq 'k') {
-		# king
-		substr($nb[0], 4, 1, '-');
-		substr($nb[0], 6, 1, $piece);
-		
-		# rook
-		substr($nb[0], 7, 1, '-');
-		substr($nb[0], 5, 1, 'r');
-				
-		return \@nb;
-	}
-
-	# black long castling
-	if ($move eq 'e8c8' && $piece eq 'k') {
-		# king
-		substr($nb[0], 4, 1, '-');
-		substr($nb[0], 2, 1, $piece);
-		
-		# rook
-		substr($nb[0], 0, 1, '-');
-		substr($nb[0], 3, 1, 'r');
-				
-		return \@nb;
-	}
-
-	# check if the from-piece is a pawn
-	if (lc($piece) eq 'p') {
-		# attack?
-		if ($from_col != $to_col) {
-			# en passant?
-			if (substr($board->[$to_row], $to_col, 1) eq '-') {
-				if ($piece eq 'p') {
-					substr($nb[$to_row + 1], $to_col, 1, '-');
-				} else {
-					substr($nb[$to_row - 1], $to_col, 1, '-');
-				}
-			}
-		} else {
-			if ($promo ne '') {
-				if ($piece eq 'p') {
-					$piece = $promo;
-				} else {
-					$piece = uc($promo);
-				}
-			}
-		}
-	}
-
-	# update the board
-	substr($nb[$from_row], $from_col, 1, '-');
-	substr($nb[$to_row], $to_col, 1, $piece);
-
-	return \@nb;
-}
-
-sub prettyprint_pv {
+sub prettyprint_pv_no_cache {
 	my ($board, @pvs) = @_;
 
 	if (scalar @pvs == 0 || !defined($pvs[0])) {
@@ -522,112 +525,88 @@ sub prettyprint_pv {
 	}
 
 	my $pv = shift @pvs;
-	my $from_col = col_letter_to_num(substr($pv, 0, 1));
-	my $from_row = row_letter_to_num(substr($pv, 1, 1));
-	my $to_col   = col_letter_to_num(substr($pv, 2, 1));
-	my $to_row   = row_letter_to_num(substr($pv, 3, 1));
-	my $promo    = substr($pv, 4, 1);
-
-	my $nb = make_move($board, $from_row, $from_col, $to_row, $to_col, $promo);
-	my $piece = substr($board->[$from_row], $from_col, 1);
-
-	if ($piece eq '-') {
-		die "Invalid move $pv";
-	}
+	my ($from_row, $from_col, $to_row, $to_col, $promo) = parse_uci_move($pv);
+	my ($pretty, $nb) = $board->prettyprint_move($from_row, $from_col, $to_row, $to_col, $promo);
+	return ( $pretty, prettyprint_pv_no_cache($nb, @pvs) );
+}
 
-	# white short castling
-	if ($pv eq 'e1g1' && $piece eq 'K') {
-		return ('0-0', prettyprint_pv($nb, @pvs));
-	}
+sub prettyprint_pv {
+	my ($pos, @pvs) = @_;
 
-	# white long castling
-	if ($pv eq 'e1c1' && $piece eq 'K') {
-		return ('0-0-0', prettyprint_pv($nb, @pvs));
+	my $cachekey = $pos->fen() . join('', @pvs);
+	if (exists($pos->{'prettyprint_cache'}{$cachekey})) {
+		return @{$pos->{'prettyprint_cache'}{$cachekey}};
+	} else {
+		my @res = prettyprint_pv_no_cache($pos->{'board'}, @pvs);
+		$pos->{'prettyprint_cache'}{$cachekey} = \@res;
+		return @res;
 	}
+}
 
-	# black short castling
-	if ($pv eq 'e8g8' && $piece eq 'k') {
-		return ('0-0', prettyprint_pv($nb, @pvs));
-	}
+my %tbprobe_cache = ();
 
-	# black long castling
-	if ($pv eq 'e8c8' && $piece eq 'k') {
-		return ('0-0-0', prettyprint_pv($nb, @pvs));
-	}
+sub complete_using_tbprobe {
+	my ($pos, $info, $mpv) = @_;
 
-	my $pretty;
+	# We need Fathom installed to do standalone TB probes.
+	return if (!defined($remoteglotconf::fathom_cmdline));
 
-	# check if the from-piece is a pawn
-	if (lc($piece) eq 'p') {
-		# attack?
-		if ($from_col != $to_col) {
-			$pretty = substr($pv, 0, 1) . 'x' . substr($pv, 2, 2);
-		} else {
-			$pretty = substr($pv, 2, 2);
+	# If we already have a mate, don't bother; in some cases, it would even be
+	# better than a tablebase score.
+	return if defined($info->{'score_mate' . $mpv});
 
-			if (length($pv) == 5) {
-				# promotion
-				$pretty .= "=";
-				$pretty .= uc(substr($pv, 4, 1));
+	# If we have a draw or near-draw score, there's also not much interesting
+	# we could add from a tablebase. We only really want mates.
+	return if ($info->{'score_cp' . $mpv} >= -12250 && $info->{'score_cp' . $mpv} <= 12250);
 
-				if ($piece eq 'p') {
-					$piece = substr($pv, 4, 1);
-				} else {
-					$piece = uc(substr($pv, 4, 1));
-				}
-			}
-		}
+	# Run through the PV until we are at a 6-man position.
+	# TODO: We could in theory only have 5-man data.
+	my @pv = @{$info->{'pv' . $mpv}};
+	my $key = $pos->fen() . " " . join('', @pv);
+	my @moves = ();
+	if (exists($tbprobe_cache{$key})) {
+		@moves = @{$tbprobe_cache{$key}};
 	} else {
-		$pretty = uc($piece);
-
-		# see how many of these pieces could go here, in all
-		my $num_total = 0;
-		for my $col (0..7) {
-			for my $row (0..7) {
-				next unless (substr($board->[$row], $col, 1) eq $piece);
-				++$num_total if (can_reach($board, $piece, $row, $col, $to_row, $to_col));
-			}
+		if ($mpv ne '') {
+			# Force doing at least one move of the PV.
+			my $move = shift @pv;
+			push @moves, $move;
+			$pos = $pos->make_move(parse_uci_move($move));
 		}
 
-		# see how many of these pieces from the given row could go here
-		my $num_row = 0;
-		for my $col (0..7) {
-			next unless (substr($board->[$from_row], $col, 1) eq $piece);
-			++$num_row if (can_reach($board, $piece, $from_row, $col, $to_row, $to_col));
-		}
-		
-		# and same for columns
-		my $num_col = 0;
-		for my $row (0..7) {
-			next unless (substr($board->[$row], $from_col, 1) eq $piece);
-			++$num_col if (can_reach($board, $piece, $row, $from_col, $to_row, $to_col));
-		}
-		
-		# see if we need to disambiguate
-		if ($num_total > 1) {
-			if ($num_col == 1) {
-				$pretty .= substr($pv, 0, 1);
-			} elsif ($num_row == 1) {
-				$pretty .= substr($pv, 1, 1);
-			} else {
-				$pretty .= substr($pv, 0, 2);
-			}
+		while ($pos->num_pieces() > 6 && $#pv > -1) {
+			my $move = shift @pv;
+			push @moves, $move;
+			$pos = $pos->make_move(parse_uci_move($move));
 		}
 
-		# attack?
-		if (substr($board->[$to_row], $to_col, 1) ne '-') {
-			$pretty .= 'x';
+		return if ($pos->num_pieces() > 6);
+
+		my $fen = $pos->fen();
+		my $pgn_text = `fathom --path=/srv/syzygy "$fen"`;
+		my $pgn = Chess::PGN::Parse->new(undef, $pgn_text);
+		return if (!defined($pgn) || !$pgn->read_game() || ($pgn->result ne '0-1' && $pgn->result ne '1-0'));
+		$pgn->quick_parse_game;
+		$info->{'pv' . $mpv} = \@moves;
+
+		# Splice the PV from the tablebase onto what we have so far.
+		for my $move (@{$pgn->moves}) {
+			my $uci_move;
+			($pos, $uci_move) = $pos->make_pretty_move($move);
+			push @moves, $uci_move;
 		}
 
-		$pretty .= substr($pv, 2, 2);
+		$tbprobe_cache{$key} = \@moves;
 	}
 
-	if (in_mate($nb)) {
-		$pretty .= '#';
-	} elsif (in_check($nb) ne 'none') {
-		$pretty .= '+';
+	$info->{'pv' . $mpv} = \@moves;
+
+	my $matelen = int((1 + scalar @moves) / 2);
+	if ((scalar @moves) % 2 == 0) {
+		$info->{'score_mate' . $mpv} = -$matelen;
+	} else {
+		$info->{'score_mate' . $mpv} = $matelen;
 	}
-	return ($pretty, prettyprint_pv($nb, @pvs));
 }
 
 sub output {
@@ -637,12 +616,53 @@ sub output {
 
 	# Don't update too often.
 	my $age = Time::HiRes::tv_interval($latest_update);
-	if ($age < $update_max_interval) {
-		Time::HiRes::alarm($update_max_interval + 0.01 - $age);
+	if ($age < $remoteglotconf::update_max_interval) {
+		my $wait = $remoteglotconf::update_max_interval + 0.01 - $age;
+		$output_timer = AnyEvent->timer(after => $wait, cb => \&output);
 		return;
 	}
 	
 	my $info = $engine->{'info'};
+
+	#
+	# If we have tablebase data from a previous lookup, replace the
+	# engine data with the data from the tablebase.
+	#
+	my $fen = $pos_calculating->fen();
+	if (exists($tb_cache{$fen})) {
+		for my $key (qw(pv score_cp score_mate nodes nps depth seldepth tbhits)) {
+			delete $info->{$key . '1'};
+			delete $info->{$key};
+		}
+		$info->{'nodes'} = 0;
+		$info->{'nps'} = 0;
+		$info->{'depth'} = 0;
+		$info->{'seldepth'} = 0;
+		$info->{'tbhits'} = 0;
+
+		my $t = $tb_cache{$fen};
+		my $pv = $t->{'pv'};
+		my $matelen = int((1 + $t->{'score'}) / 2);
+		if ($t->{'result'} eq '1/2-1/2') {
+			$info->{'score_cp'} = 0;
+		} elsif ($t->{'result'} eq '1-0') {
+			if ($pos_calculating->{'toplay'} eq 'B') {
+				$info->{'score_mate'} = -$matelen;
+			} else {
+				$info->{'score_mate'} = $matelen;
+			}
+		} else {
+			if ($pos_calculating->{'toplay'} eq 'B') {
+				$info->{'score_mate'} = $matelen;
+			} else {
+				$info->{'score_mate'} = -$matelen;
+			}
+		}
+		$info->{'pv'} = $pv;
+		$info->{'tablebase'} = 1;
+	} else {
+		$info->{'tablebase'} = 0;
+	}
 	
 	#
 	# Some programs _always_ report MultiPV, even with only one PV.
@@ -653,6 +673,8 @@ sub output {
 		for my $key (qw(pv score_cp score_mate nodes nps depth seldepth tbhits)) {
 			if (exists($info->{$key . '1'})) {
 				$info->{$key} = $info->{$key . '1'};
+			} else {
+				delete $info->{$key};
 			}
 		}
 	}
@@ -665,12 +687,12 @@ sub output {
 	eval {
 		my $dummy;
 		if (exists($info->{'pv'})) {
-			$dummy = prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv'}});
+			$dummy = prettyprint_pv($pos_calculating, @{$info->{'pv'}});
 		}
 	
 		my $mpv = 1;
 		while (exists($info->{'pv' . $mpv})) {
-			$dummy = prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv' . $mpv}});
+			$dummy = prettyprint_pv($pos_calculating, @{$info->{'pv' . $mpv}});
 			++$mpv;
 		}
 	};
@@ -679,8 +701,19 @@ sub output {
 		return;
 	}
 
+	# Now do our own Syzygy tablebase probes to convert scores like +123.45 to mate.
+	if (exists($info->{'pv'})) {
+		complete_using_tbprobe($pos_calculating, $info, '');
+	}
+
+	my $mpv = 1;
+	while (exists($info->{'pv' . $mpv})) {
+		complete_using_tbprobe($pos_calculating, $info, $mpv);
+		++$mpv;
+	}
+
 	output_screen();
-	output_json();
+	output_json(0);
 	$latest_update = [Time::HiRes::gettimeofday];
 }
 
@@ -731,7 +764,7 @@ sub output_screen {
 			}
 
 			$text .= ":\n";
-			$text .= "  " . join(', ', prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv' . $mpv}})) . "\n";
+			$text .= "  " . join(', ', prettyprint_pv($pos_calculating, @{$info->{'pv' . $mpv}})) . "\n";
 			$text .= "\n";
 			++$mpv;
 		}
@@ -739,7 +772,7 @@ sub output_screen {
 		# single-PV
 		my $score = long_score($info, $pos_calculating, '');
 		$text .= "  $score\n" if defined($score);
-		$text .=  "  PV: " . join(', ', prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv'}}));
+		$text .=  "  PV: " . join(', ', prettyprint_pv($pos_calculating, @{$info->{'pv'}}));
 		$text .=  "\n";
 
 		if (exists($info->{'nodes'}) && exists($info->{'nps'}) && exists($info->{'depth'})) {
@@ -751,37 +784,39 @@ sub output_screen {
 		}
 		if (exists($info->{'tbhits'}) && $info->{'tbhits'} > 0) {
 			if ($info->{'tbhits'} == 1) {
-				$text .= ", one Nalimov hit";
+				$text .= ", one Syzygy hit";
 			} else {
-				$text .= sprintf ", %u Nalimov hits", $info->{'tbhits'};
+				$text .= sprintf ", %u Syzygy hits", $info->{'tbhits'};
 			}
 		}
 		$text .= "\n\n";
 	}
 
-	#$text .= book_info($pos_calculating->{'fen'}, $pos_calculating->{'board'}, $pos_calculating->{'toplay'});
+	#$text .= book_info($pos_calculating->fen(), $pos_calculating->{'board'}, $pos_calculating->{'toplay'});
 
 	my @refutation_lines = ();
-	for (my $mpv = 1; $mpv < 500; ++$mpv) {
-		my $info = $engine2->{'info'};
-		last if (!exists($info->{'pv' . $mpv}));
-		eval {
-			my $pv = $info->{'pv' . $mpv};
-
-			my $pretty_move = join('', prettyprint_pv($pos_calculating_second_engine->{'board'}, $pv->[0]));
-			my @pretty_pv = prettyprint_pv($pos_calculating_second_engine->{'board'}, @$pv);
-			if (scalar @pretty_pv > 5) {
-				@pretty_pv = @pretty_pv[0..4];
-				push @pretty_pv, "...";
-			}
-			my $key = $pretty_move;
-			my $line = sprintf("  %-6s %6s %3s  %s",
-				$pretty_move,
-				short_score($info, $pos_calculating_second_engine, $mpv, 1),
-				"d" . $info->{'depth' . $mpv},
-				join(', ', @pretty_pv));
-			push @refutation_lines, [ $key, $line ];
-		};
+	if (defined($engine2)) {
+		for (my $mpv = 1; $mpv < 500; ++$mpv) {
+			my $info = $engine2->{'info'};
+			last if (!exists($info->{'pv' . $mpv}));
+			eval {
+				complete_using_tbprobe($pos_calculating_second_engine, $info, $mpv);
+				my $pv = $info->{'pv' . $mpv};
+				my $pretty_move = join('', prettyprint_pv($pos_calculating_second_engine, $pv->[0]));
+				my @pretty_pv = prettyprint_pv($pos_calculating_second_engine, @$pv);
+				if (scalar @pretty_pv > 5) {
+					@pretty_pv = @pretty_pv[0..4];
+					push @pretty_pv, "...";
+				}
+				my $key = $pretty_move;
+				my $line = sprintf("  %-6s %6s %3s  %s",
+					$pretty_move,
+					short_score($info, $pos_calculating_second_engine, $mpv),
+					"d" . $info->{'depth' . $mpv},
+					join(', ', @pretty_pv));
+				push @refutation_lines, [ $key, $line ];
+			};
+		}
 	}
 
 	if ($#refutation_lines >= 0) {
@@ -797,327 +832,233 @@ sub output_screen {
 		print $text;
 		$last_text = $text;
 	}
-
-	# Now construct the tell text, if any
-	return if (!defined($telltarget));
-
-	my $tell_text = '';
-
-	if (exists($id->{'name'})) {
-		$tell_text .= "Analysis by $id->{'name'} -- see http://analysis.sesse.net/ for more information\n";
-	} else {
-		$tell_text .= "Computer analysis -- http://analysis.sesse.net/ for more information\n";
-	}
-
-	if (exists($info->{'pv1'}) && exists($info->{'pv2'})) {
-		# multi-PV
-		my $mpv = 1;
-		while (exists($info->{'pv' . $mpv})) {
-			$tell_text .= sprintf "  PV%2u", $mpv;
-			my $score = short_score($info, $pos_calculating, $mpv);
-			$tell_text .= "  ($score)" if (defined($score));
-
-			if (exists($info->{'depth' . $mpv})) {
-				$tell_text .= sprintf " (%2u ply)", $info->{'depth' . $mpv};
-			}
-
-			$tell_text .= ": ";
-			$tell_text .= join(', ', prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv' . $mpv}}));
-			$tell_text .= "\n";
-			++$mpv;
-		}
-	} else {
-		# single-PV
-		my $score = long_score($info, $pos_calculating, '');
-		$tell_text .= "  $score\n" if defined($score);
-		$tell_text .= "  PV: " . join(', ', prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv'}}));
-		if (exists($info->{'depth'})) {
-			$tell_text .= sprintf " (depth %u ply)", $info->{'depth'};
-		}
-		$tell_text .=  "\n";
-	}
-
-	# see if a new tell is called for -- it is if the delay has expired _and_
-	# this is not simply a repetition of the last one
-	if ($last_told_text ne $tell_text) {
-		my $now = time;
-		for my $iv (@tell_intervals) {
-			last if ($now - $last_move < $iv);
-			next if ($last_tell - $last_move >= $iv);
-
-			for my $line (split /\n/, $tell_text) {
-				$t->print("tell $telltarget [$target] $line");
-			}
-
-			$last_told_text = $text;
-			$last_tell = $now;
-
-			last;
-		}
-	}
 }
 
 sub output_json {
+	my $historic_json_only = shift;
 	my $info = $engine->{'info'};
 
 	my $json = {};
-	$json->{'position'} = $pos_calculating;
-	$json->{'id'} = $engine->{'id'};
-	$json->{'score'} = long_score($info, $pos_calculating, '');
+	$json->{'position'} = $pos_calculating->to_json_hash();
+	$json->{'engine'} = $engine->{'id'};
+	if (defined($remoteglotconf::engine_url)) {
+		$json->{'engine'}{'url'} = $remoteglotconf::engine_url;
+	}
+	if (defined($remoteglotconf::engine_details)) {
+		$json->{'engine'}{'details'} = $remoteglotconf::engine_details;
+	}
+	my @grpc_backends = ();
+	if (defined($remoteglotconf::engine_grpc_backend)) {
+		push @grpc_backends, $remoteglotconf::engine_grpc_backend;
+	}
+	if (defined($remoteglotconf::engine2_grpc_backend)) {
+		push @grpc_backends, $remoteglotconf::engine2_grpc_backend;
+	}
+	$json->{'internal'}{'grpc_backends'} = \@grpc_backends;
+	if (defined($remoteglotconf::move_source)) {
+		$json->{'move_source'} = $remoteglotconf::move_source;
+	}
+	if (defined($remoteglotconf::move_source_url)) {
+		$json->{'move_source_url'} = $remoteglotconf::move_source_url;
+	}
+	$json->{'score'} = score_digest($info, $pos_calculating, '');
+	$json->{'using_lomonosov'} = defined($remoteglotconf::tb_serial_key);
 
 	$json->{'nodes'} = $info->{'nodes'};
 	$json->{'nps'} = $info->{'nps'};
 	$json->{'depth'} = $info->{'depth'};
 	$json->{'tbhits'} = $info->{'tbhits'};
 	$json->{'seldepth'} = $info->{'seldepth'};
-
-	# single-PV only for now
-	$json->{'pv_uci'} = $info->{'pv'};
-	$json->{'pv_pretty'} = [ prettyprint_pv($pos_calculating->{'board'}, @{$info->{'pv'}}) ];
+	$json->{'tablebase'} = $info->{'tablebase'};
+	$json->{'pv'} = [ prettyprint_pv($pos_calculating, @{$info->{'pv'}}) ];
 
 	my %refutation_lines = ();
 	my @refutation_lines = ();
-	for (my $mpv = 1; $mpv < 500; ++$mpv) {
-		my $info = $engine2->{'info'};
-		my $pretty_move = "";
-		my @pretty_pv = ();
-		last if (!exists($info->{'pv' . $mpv}));
-
-		eval {
-			my $pv = $info->{'pv' . $mpv};
-			my $pretty_move = join('', prettyprint_pv($pos_calculating->{'board'}, $pv->[0]));
-			my @pretty_pv = prettyprint_pv($pos_calculating->{'board'}, @$pv);
-			$refutation_lines{$pv->[0]} = {
-				sort_key => $pretty_move,
-				depth => $info->{'depth' . $mpv},
-				score_sort_key => score_sort_key($info, $pos_calculating, $mpv, 0),
-				pretty_score => short_score($info, $pos_calculating, $mpv, 0),
-				pretty_move => $pretty_move,
-				pv_pretty => \@pretty_pv,
+	if (defined($engine2)) {
+		for (my $mpv = 1; $mpv < 500; ++$mpv) {
+			my $info = $engine2->{'info'};
+			my $pretty_move = "";
+			my @pretty_pv = ();
+			last if (!exists($info->{'pv' . $mpv}));
+
+			eval {
+				complete_using_tbprobe($pos_calculating, $info, $mpv);
+				my $pv = $info->{'pv' . $mpv};
+				my $pretty_move = join('', prettyprint_pv($pos_calculating, $pv->[0]));
+				my @pretty_pv = prettyprint_pv($pos_calculating, @$pv);
+				$refutation_lines{$pretty_move} = {
+					depth => $info->{'depth' . $mpv},
+					score => score_digest($info, $pos_calculating, $mpv),
+					move => $pretty_move,
+					pv => \@pretty_pv,
+				};
 			};
-			$refutation_lines{$pv->[0]}->{'pv_uci'} = $pv;
-		};
+		}
 	}
 	$json->{'refutation_lines'} = \%refutation_lines;
 
-	open my $fh, ">analysis.json.tmp"
-		or return;
-	print $fh JSON::XS::encode_json($json);
-	close $fh;
-	rename("analysis.json.tmp", "analysis.json");	
-}
-
-sub find_kings {
-	my $board = shift;
-	my ($wkr, $wkc, $bkr, $bkc);
-
-	for my $row (0..7) {
-		for my $col (0..7) {
-			my $piece = substr($board->[$row], $col, 1);
-			if ($piece eq 'K') {
-				($wkr, $wkc) = ($row, $col);
-			} elsif ($piece eq 'k') {
-				($bkr, $bkc) = ($row, $col);
+	# Piece together historic score information, to the degree we have it.
+	if (!$historic_json_only && exists($pos_calculating->{'history'})) {
+		my %score_history = ();
+
+		my $q = $dbh->prepare('SELECT * FROM scores WHERE id=?');
+		my $pos = Position->start_pos('white', 'black');
+		my $halfmove_num = 0;
+		for my $move (@{$pos_calculating->{'history'}}) {
+			my $id = id_for_pos($pos, $halfmove_num);
+			my $ref = $dbh->selectrow_hashref($q, undef, $id);
+			if (defined($ref)) {
+				$score_history{$halfmove_num} = [
+					$ref->{'score_type'},
+					$ref->{'score_value'}
+				];
 			}
+			++$halfmove_num;
+			($pos) = $pos->make_pretty_move($move);
 		}
-	}
-
-	return ($wkr, $wkc, $bkr, $bkc);
-}
-
-sub in_mate {
-	my $board = shift;
-	my $check = in_check($board);
-	return 0 if ($check eq 'none');
-
-	# try all possible moves for the side in check
-	for my $row (0..7) {
-		for my $col (0..7) {
-			my $piece = substr($board->[$row], $col, 1);
-			next if ($piece eq '-');
-
-			if ($check eq 'white') {
-				next if ($piece eq lc($piece));
+		$q->finish;
+
+		# If at any point we are missing 10 consecutive moves,
+		# truncate the history there. This is so we don't get into
+		# a situation where we e.g. start analyzing at move 45,
+		# but we have analysis for 1. e4 from some completely different game
+		# and thus show a huge hole.
+		my $consecutive_missing = 0;
+		my $truncate_until = 0;
+		for (my $i = $halfmove_num; $i --> 0; ) {
+			if ($consecutive_missing >= 10) {
+				delete $score_history{$i};
+				next;
+			}
+			if (exists($score_history{$i})) {
+				$consecutive_missing = 0;
 			} else {
-				next if ($piece eq uc($piece));
+				++$consecutive_missing;
 			}
+		}
 
-			for my $dest_row (0..7) {
-				for my $dest_col (0..7) {
-					next if ($row == $dest_row && $col == $dest_col);
-					next unless (can_reach($board, $piece, $row, $col, $dest_row, $dest_col));
-
-					my @nb = @$board;
-					substr($nb[$row], $col, 1, '-');
-					substr($nb[$dest_row], $dest_col, 1, $piece);
+		$json->{'score_history'} = \%score_history;
+	}
 
-					my $new_check = in_check(\@nb);
-					return 0 if ($new_check ne $check && $new_check ne 'both');
+	# Give out a list of other games going on. (Empty is fine.)
+	# TODO: Don't bother reading our own file, the data will be stale anyway.
+	if (!$historic_json_only) {
+		my @games = ();
+
+		my $q = $dbh->prepare('SELECT * FROM current_games ORDER BY priority DESC, id');
+		$q->execute;
+		while (my $ref = $q->fetchrow_hashref) {
+			eval {
+				my $other_game_contents = File::Slurp::read_file($ref->{'json_path'});
+				my $other_game_json = JSON::XS::decode_json($other_game_contents);
+
+				die "Missing position" if (!exists($other_game_json->{'position'}));
+				my $white = $other_game_json->{'position'}{'player_w'} // die 'Missing white';
+				my $black = $other_game_json->{'position'}{'player_b'} // die 'Missing black';
+
+				my $game = {
+					id => $ref->{'id'},
+					name => "$white–$black",
+					url => $ref->{'url'},
+					hashurl => $ref->{'hash_url'},
+				};
+				if (defined($other_game_json->{'position'}{'result'})) {
+					$game->{'result'} = $other_game_json->{'position'}{'result'};
+				} else {
+					$game->{'score'} = $other_game_json->{'score'};
 				}
+				push @games, $game;
+			};
+			if ($@) {
+				warn "Could not add external game " . $ref->{'json_path'} . ": $@";
 			}
 		}
-	}
-
-	# nothing to do; mate
-	return 1;
-}
 
-sub in_check {
-	my $board = shift;
-	my ($black_check, $white_check) = (0, 0);
-
-	my ($wkr, $wkc, $bkr, $bkc) = find_kings($board);
-
-	# check all pieces for the possibility of threatening the two kings
-	for my $row (0..7) {
-		for my $col (0..7) {
-			my $piece = substr($board->[$row], $col, 1);
-			next if ($piece eq '-');
-		
-			if (uc($piece) eq $piece) {
-				# white piece
-				$black_check = 1 if (can_reach($board, $piece, $row, $col, $bkr, $bkc));
-			} else {
-				# black piece
-				$white_check = 1 if (can_reach($board, $piece, $row, $col, $wkr, $wkc));
-			}
+		if (scalar @games > 0) {
+			$json->{'games'} = \@games;
 		}
 	}
 
-	if ($black_check && $white_check) {
-		return 'both';
-	} elsif ($black_check) {
-		return 'black';
-	} elsif ($white_check) {
-		return 'white';
-	} else {
-		return 'none';
-	}
-}
-
-sub can_reach {
-	my ($board, $piece, $from_row, $from_col, $to_row, $to_col) = @_;
-	
-	# can't eat your own piece
-	my $dest_piece = substr($board->[$to_row], $to_col, 1);
-	if ($dest_piece ne '-') {
-		return 0 if (($piece eq lc($piece)) == ($dest_piece eq lc($dest_piece)));
-	}
-
-	if (lc($piece) eq 'k') {
-		return (abs($from_row - $to_row) <= 1 && abs($from_col - $to_col) <= 1);
+	my $json_enc = JSON::XS->new;
+	$json_enc->canonical(1);
+	my $encoded = $json_enc->encode($json);
+	unless ($historic_json_only || !defined($remoteglotconf::json_output) ||
+	        (defined($last_written_json) && $last_written_json eq $encoded)) {
+		atomic_set_contents($remoteglotconf::json_output, $encoded);
+		$last_written_json = $encoded;
 	}
-	if (lc($piece) eq 'r') {
-		return 0 unless ($from_row == $to_row || $from_col == $to_col);
-
-		# check that there's a clear passage
-		if ($from_row == $to_row) {
-			if ($from_col > $to_col) {
-				($to_col, $from_col) = ($from_col, $to_col);
-			}
-
-			for my $c (($from_col+1)..($to_col-1)) {
-				my $middle_piece = substr($board->[$to_row], $c, 1);
-				return 0 if ($middle_piece ne '-');	
-			}
-
-			return 1;
-		} else {
-			if ($from_row > $to_row) {
-				($to_row, $from_row) = ($from_row, $to_row);
-			}
 
-			for my $r (($from_row+1)..($to_row-1)) {
-				my $middle_piece = substr($board->[$r], $to_col, 1);
-				return 0 if ($middle_piece ne '-');	
+	if (exists($pos_calculating->{'history'}) &&
+	    defined($remoteglotconf::json_history_dir)) {
+		my $id = id_for_pos($pos_calculating);
+		my $filename = $remoteglotconf::json_history_dir . "/" . $id . ".json";
+
+		# Overwrite old analysis (assuming it exists at all) if we're
+		# using a different engine, or if we've calculated deeper.
+		# nodes is used as a tiebreaker. Don't bother about Multi-PV
+		# data; it's not that important.
+		my ($old_engine, $old_depth, $old_nodes) = get_json_analysis_stats($id);
+		my $new_depth = $json->{'depth'} // 0;
+		my $new_nodes = $json->{'nodes'} // 0;
+		if (!defined($old_engine) ||
+		    $old_engine ne $json->{'engine'}{'name'} ||
+		    $new_depth > $old_depth ||
+		    ($new_depth == $old_depth && $new_nodes >= $old_nodes)) {
+			atomic_set_contents($filename, $encoded);
+			if (defined($json->{'score'})) {
+				$dbh->do('INSERT INTO scores (id, score_type, score_value, engine, depth, nodes) VALUES (?,?,?,?,?,?) ' .
+				         '    ON CONFLICT (id) DO UPDATE SET ' .
+				         '        score_type=EXCLUDED.score_type, ' .
+					 '        score_value=EXCLUDED.score_value, ' .
+					 '        engine=EXCLUDED.engine, ' .
+					 '        depth=EXCLUDED.depth, ' .
+					 '        nodes=EXCLUDED.nodes',
+					undef,
+					$id, $json->{'score'}[0], $json->{'score'}[1],
+					$json->{'engine'}{'name'}, $new_depth, $new_nodes);
 			}
-
-			return 1;
 		}
 	}
-	if (lc($piece) eq 'b') {
-		return 0 unless (abs($from_row - $to_row) == abs($from_col - $to_col));
+}
 
-		my $dr = ($to_row - $from_row) / abs($to_row - $from_row);
-		my $dc = ($to_col - $from_col) / abs($to_col - $from_col);
+sub atomic_set_contents {
+	my ($filename, $contents) = @_;
 
-		my $r = $from_row + $dr;
-		my $c = $from_col + $dc;
+	open my $fh, ">", $filename . ".tmp"
+		or return;
+	print $fh $contents;
+	close $fh;
+	rename($filename . ".tmp", $filename);
+}
 
-		while ($r != $to_row) {
-			my $middle_piece = substr($board->[$r], $c, 1);
-			return 0 if ($middle_piece ne '-');
-			
-			$r += $dr;
-			$c += $dc;
-		}
+sub id_for_pos {
+	my ($pos, $halfmove_num) = @_;
 
-		return 1;
-	}
-	if (lc($piece) eq 'n') {
-		my $diff_r = abs($from_row - $to_row);
-		my $diff_c = abs($from_col - $to_col);
-		return 1 if ($diff_r == 2 && $diff_c == 1);
-		return 1 if ($diff_r == 1 && $diff_c == 2);
-		return 0;
-	}
-	if ($piece eq 'q') {
-		return (can_reach($board, 'r', $from_row, $from_col, $to_row, $to_col) ||
-		        can_reach($board, 'b', $from_row, $from_col, $to_row, $to_col));
-	}
-	if ($piece eq 'Q') {
-		return (can_reach($board, 'R', $from_row, $from_col, $to_row, $to_col) ||
-		        can_reach($board, 'B', $from_row, $from_col, $to_row, $to_col));
-	}
+	$halfmove_num //= scalar @{$pos->{'history'}};
+	(my $fen = $pos->fen()) =~ tr,/ ,-_,;
+	return "move$halfmove_num-$fen";
+}
 
-	# TODO: en passant
-	if ($piece eq 'p') {
-		# black pawn
-		if ($to_col == $from_col && $to_row == $from_row + 1) {
-			return ($dest_piece eq '-');
-		}
-		if ($to_col == $from_col && $from_row == 1 && $to_row == 3) {
-			my $middle_piece = substr($board->[2], $to_col, 1);
-			return ($dest_piece eq '-' && $middle_piece eq '-');
-		}
-		if (abs($to_col - $from_col) == 1 && $to_row == $from_row + 1) {
-			return ($dest_piece ne '-');
-		}
-		return 0;
-	}
-	if ($piece eq 'P') {
-		# white pawn
-		if ($to_col == $from_col && $to_row == $from_row - 1) {
-			return ($dest_piece eq '-');
-		}
-		if ($to_col == $from_col && $from_row == 6 && $to_row == 4) {
-			my $middle_piece = substr($board->[5], $to_col, 1);
-			return ($dest_piece eq '-' && $middle_piece eq '-');
-		}
-		if (abs($to_col - $from_col) == 1 && $to_row == $from_row - 1) {
-			return ($dest_piece ne '-');
-		}
-		return 0;
+sub get_json_analysis_stats {
+	my $id = shift;
+	my $ref = $dbh->selectrow_hashref('SELECT * FROM scores WHERE id=?', undef, $id);
+	if (defined($ref)) {
+		return ($ref->{'engine'}, $ref->{'depth'}, $ref->{'nodes'});
+	} else {
+		return ('', 0, 0);
 	}
-	
-	# unknown piece
-	return 0;
 }
 
 sub uciprint {
 	my ($engine, $msg) = @_;
-	print { $engine->{'write'} } "$msg\n";
+	$engine->print($msg);
 	print UCILOG localtime() . " $engine->{'tag'} => $msg\n";
 }
 
 sub short_score {
-	my ($info, $pos, $mpv, $invert) = @_;
-
-	$invert //= 0;
-	if ($pos->{'toplay'} eq 'B') {
-		$invert = !$invert;
-	}
+	my ($info, $pos, $mpv) = @_;
 
+	my $invert = ($pos->{'toplay'} eq 'B');
 	if (defined($info->{'score_mate' . $mpv})) {
 		if ($invert) {
 			return sprintf "M%3d", -$info->{'score_mate' . $mpv};
@@ -1128,7 +1069,11 @@ sub short_score {
 		if (exists($info->{'score_cp' . $mpv})) {
 			my $score = $info->{'score_cp' . $mpv} * 0.01;
 			if ($score == 0) {
-				return " 0.00";
+				if ($info->{'tablebase'}) {
+					return "TB draw";
+				} else {
+					return " 0.00";
+				}
 			}
 			if ($invert) {
 				$score = -$score;
@@ -1140,22 +1085,28 @@ sub short_score {
 	return undef;
 }
 
-sub score_sort_key {
-	my ($info, $pos, $mpv, $invert) = @_;
+# Sufficient for computing long_score, short_score, plot_score and
+# (with side-to-play information) score_sort_key.
+sub score_digest {
+	my ($info, $pos, $mpv) = @_;
 
 	if (defined($info->{'score_mate' . $mpv})) {
-		if ($invert) {
-			return -(99999 - $info->{'score_mate' . $mpv});
-		} else {
-			return 99999 - $info->{'score_mate' . $mpv};
+		my $mate = $info->{'score_mate' . $mpv};
+		if ($pos->{'toplay'} eq 'B') {
+			$mate = -$mate;
 		}
+		return ['m', $mate];
 	} else {
 		if (exists($info->{'score_cp' . $mpv})) {
 			my $score = $info->{'score_cp' . $mpv};
-			if ($invert) {
+			if ($pos->{'toplay'} eq 'B') {
 				$score = -$score;
 			}
-			return $score;
+			if ($score == 0 && $info->{'tablebase'}) {
+				return ['d', undef];
+			} else {
+				return ['cp', int($score)];
+			}
 		}
 	}
 
@@ -1178,6 +1129,13 @@ sub long_score {
 	} else {
 		if (exists($info->{'score_cp' . $mpv})) {
 			my $score = $info->{'score_cp' . $mpv} * 0.01;
+			if ($score == 0) {
+				if ($info->{'tablebase'}) {
+					return "Theoretical draw";
+				} else {
+					return "Score:  0.00";
+				}
+			}
 			if ($pos->{'toplay'} eq 'B') {
 				$score = -$score;
 			}
@@ -1188,6 +1146,36 @@ sub long_score {
 	return undef;
 }
 
+# For graphs; a single number in centipawns, capped at +/- 500.
+sub plot_score {
+	my ($info, $pos, $mpv) = @_;
+
+	my $invert = ($pos->{'toplay'} eq 'B');
+	if (defined($info->{'score_mate' . $mpv})) {
+		my $mate = $info->{'score_mate' . $mpv};
+		if ($invert) {
+			$mate = -$mate;
+		}
+		if ($mate > 0) {
+			return 500;
+		} else {
+			return -500;
+		}
+	} else {
+		if (exists($info->{'score_cp' . $mpv})) {
+			my $score = $info->{'score_cp' . $mpv};
+			if ($invert) {
+				$score = -$score;
+			}
+			$score = 500 if ($score > 500);
+			$score = -500 if ($score < -500);
+			return int($score);
+		}
+	}
+
+	return undef;
+}
+
 my %book_cache = ();
 sub book_info {
 	my ($fen, $board, $toplay) = @_;
@@ -1208,7 +1196,7 @@ sub book_info {
 		if ($move eq '')  {
 			$pmove = '(current)';
 		} else {
-			($pmove) = prettyprint_pv($board, $move);
+			($pmove) = prettyprint_pv_no_cache($board, $move);
 			$pmove .= $annotation;
 		}
 
@@ -1240,62 +1228,206 @@ sub book_info {
 	return $text;
 }
 
-sub open_engine {
-	my ($cmdline, $tag) = @_;
-	my ($uciread, $uciwrite);
-	my $pid = IPC::Open2::open2($uciread, $uciwrite, $cmdline);
-
-	my $engine = {
-		pid => $pid,
-		read => $uciread,
-		readbuf => '',
-		write => $uciwrite,
-		info => {},
-		ids => {},
-		tag => $tag,
-	};
+sub extract_clock {
+	my ($pgn, $pos) = @_;
 
-	uciprint($engine, "uci");
+	# Look for extended PGN clock tags.
+	my $tags = $pgn->tags;
+	if (exists($tags->{'WhiteClock'}) && exists($tags->{'BlackClock'})) {
+		$pos->{'white_clock'} = hms_to_sec($tags->{'WhiteClock'});
+		$pos->{'black_clock'} = hms_to_sec($tags->{'BlackClock'});
+		return;
+	}
 
-	# gobble the options
-	while (<$uciread>) {
-		/uciok/ && last;
-		handle_uci($engine, $_);
+	# Look for TCEC-style time comments.
+	my $moves = $pgn->moves;
+	my $comments = $pgn->comments;
+	my $last_black_move = int((scalar @$moves) / 2);
+	my $last_white_move = int((1 + scalar @$moves) / 2);
+
+	my $black_key = $last_black_move . "b";
+	my $white_key = $last_white_move . "w";
+
+	if (exists($comments->{$white_key}) &&
+	    exists($comments->{$black_key}) &&
+	    $comments->{$white_key} =~ /(?:tl=|clk )(\d+:\d+:\d+)/ &&
+	    $comments->{$black_key} =~ /(?:tl=|clk )(\d+:\d+:\d+)/) {
+		$comments->{$white_key} =~ /(?:tl=|clk )(\d+:\d+:\d+)/;
+		$pos->{'white_clock'} = hms_to_sec($1);
+		$comments->{$black_key} =~ /(?:tl=|clk )(\d+:\d+:\d+)/;
+		$pos->{'black_clock'} = hms_to_sec($1);
+		return;
 	}
-	
-	return $engine;
+
+	delete $pos->{'white_clock'};
+	delete $pos->{'black_clock'};
 }
 
-sub read_lines {
-	my $engine = shift;
+sub hms_to_sec {
+	my $hms = shift;
+	return undef if (!defined($hms));
+	$hms =~ /(\d+):(\d+):(\d+)/;
+	return $1 * 3600 + $2 * 60 + $3;
+}
 
-	# 
-	# Read until we've got a full line -- if the engine sends part of
-	# a line and then stops we're pretty much hosed, but that should
-	# never happen.
-	#
-	while ($engine->{'readbuf'} !~ /\n/) {
-		my $tmp;
-		my $ret = sysread $engine->{'read'}, $tmp, 4096;
-
-		if (!defined($ret)) {
-			next if ($!{EINTR});
-			die "error in reading from the UCI engine: $!";
-		} elsif ($ret == 0) {
-			die "EOF from UCI engine";
+sub find_clock_start {
+	my ($pos, $prev_pos) = @_;
+
+	# If the game is over, the clock is stopped.
+	if (exists($pos->{'result'}) &&
+	    ($pos->{'result'} eq '1-0' ||
+	     $pos->{'result'} eq '1/2-1/2' ||
+	     $pos->{'result'} eq '0-1')) {
+		return;
+	}
+
+	# When we don't have any moves, we assume the clock hasn't started yet.
+	if ($pos->{'move_num'} == 1 && $pos->{'toplay'} eq 'W') {
+		if (defined($remoteglotconf::adjust_clocks_before_move)) {
+			&$remoteglotconf::adjust_clocks_before_move(\$pos->{'white_clock'}, \$pos->{'black_clock'}, 1, 'W');
+		}
+		return;
+	}
+
+	# TODO(sesse): Maybe we can get the number of moves somehow else for FICS games.
+	# The history is needed for id_for_pos.
+	if (!exists($pos->{'history'})) {
+		return;
+	}
+
+	my $id = id_for_pos($pos);
+	my $clock_info = $dbh->selectrow_hashref('SELECT * FROM clock_info WHERE id=?', undef, $id);
+	if (defined($clock_info)) {
+		$pos->{'white_clock'} //= $clock_info->{'white_clock'};
+		$pos->{'black_clock'} //= $clock_info->{'black_clock'};
+		if ($pos->{'toplay'} eq 'W') {
+			$pos->{'white_clock_target'} = $clock_info->{'white_clock_target'};
+		} else {
+			$pos->{'black_clock_target'} = $clock_info->{'black_clock_target'};
+		}
+		return;
+	}
+
+	# OK, we haven't seen this position before, so we assume the move
+	# happened right now.
+
+	# See if we should do our own clock management (ie., clock information
+	# is spurious or non-existent).
+	if (defined($remoteglotconf::adjust_clocks_before_move)) {
+		my $wc = $pos->{'white_clock'} // $prev_pos->{'white_clock'};
+		my $bc = $pos->{'black_clock'} // $prev_pos->{'black_clock'};
+		if (defined($prev_pos->{'white_clock_target'})) {
+			$wc = $prev_pos->{'white_clock_target'} - time;
+		}
+		if (defined($prev_pos->{'black_clock_target'})) {
+			$bc = $prev_pos->{'black_clock_target'} - time;
 		}
+		&$remoteglotconf::adjust_clocks_before_move(\$wc, \$bc, $pos->{'move_num'}, $pos->{'toplay'});
+		$pos->{'white_clock'} = $wc;
+		$pos->{'black_clock'} = $bc;
+	}
 
-		$engine->{'readbuf'} .= $tmp;
+	my $key = ($pos->{'toplay'} eq 'W') ? 'white_clock' : 'black_clock';
+	if (!exists($pos->{$key})) {
+		# No clock information.
+		return;
+	}
+	my $time_left = $pos->{$key};
+	my ($white_clock_target, $black_clock_target);
+	if ($pos->{'toplay'} eq 'W') {
+		$white_clock_target = $pos->{'white_clock_target'} = time + $time_left;
+	} else {
+		$black_clock_target = $pos->{'black_clock_target'} = time + $time_left;
 	}
+	local $dbh->{AutoCommit} = 0;
+	$dbh->do('DELETE FROM clock_info WHERE id=?', undef, $id);
+	$dbh->do('INSERT INTO clock_info (id, white_clock, black_clock, white_clock_target, black_clock_target) VALUES (?, ?, ?, ?, ?)', undef,
+		$id, $pos->{'white_clock'}, $pos->{'black_clock'}, $white_clock_target, $black_clock_target);
+	$dbh->commit;
+}
+
+sub schedule_tb_lookup {
+	return if (!defined($remoteglotconf::tb_serial_key));
+	my $pos = $pos_waiting // $pos_calculating;
+	return if (exists($tb_cache{$pos->fen()}));
+
+	# If there's more than seven pieces, there's not going to be an answer,
+	# so don't bother.
+	return if ($pos->num_pieces() > 7);
+
+	# Max one at a time. If it's still relevant when it returns,
+	# schedule_tb_lookup() will be called again.
+	return if ($tb_lookup_running);
+
+	$tb_lookup_running = 1;
+	my $url = 'http://158.250.18.203:6904/tasks/addtask?auth.login=' .
+		$remoteglotconf::tb_serial_key .
+		'&auth.password=aquarium&type=0&fen=' . 
+		URI::Escape::uri_escape($pos->fen());
+	print TBLOG "Downloading $url...\n";
+	AnyEvent::HTTP::http_get($url, sub {
+		handle_tb_lookup_return(@_, $pos, $pos->fen());
+	});
+}
+
+sub handle_tb_lookup_return {
+	my ($body, $header, $pos, $fen) = @_;
+	print TBLOG "Response for [$fen]:\n";
+	print TBLOG $header . "\n\n";
+	print TBLOG $body . "\n\n";
+	eval {
+		my $response = JSON::XS::decode_json($body);
+		if ($response->{'ErrorCode'} != 0) {
+			die "Unknown tablebase server error: " . $response->{'ErrorDesc'};
+		}
+		my $state = $response->{'Response'}{'StateString'};
+		if ($state eq 'COMPLETE') {
+			my $pgn = Chess::PGN::Parse->new(undef, $response->{'Response'}{'Moves'});
+			if (!defined($pgn) || !$pgn->read_game()) {
+				warn "Error in parsing PGN\n";
+			} else {
+				$pgn->quick_parse_game;
+				my $pvpos = $pos;
+				my $moves = $pgn->moves;
+				my @uci_moves = ();
+				for my $move (@$moves) {
+					my $uci_move;
+					($pvpos, $uci_move) = $pvpos->make_pretty_move($move);
+					push @uci_moves, $uci_move;
+				}
+				$tb_cache{$fen} = {
+					result => $pgn->result,
+					pv => \@uci_moves,
+					score => $response->{'Response'}{'Score'},
+				};
+				output();
+			}
+		} elsif ($state =~ /QUEUED/ || $state =~ /PROCESSING/) {
+			# Try again in a second. Note that if we have changed
+			# position in the meantime, we might query a completely
+			# different position! But that's fine.
+		} else {
+			die "Unknown response state " . $state;
+		}
 
-	# Blah.
-	my @lines = ();
-	while ($engine->{'readbuf'} =~ s/^([^\n]*)\n//) {
-		my $line = $1;
-		$line =~ tr/\r\n//d;
-		push @lines, $line;
+		# Wait a second before we schedule another one.
+		$tb_retry_timer = AnyEvent->timer(after => 1.0, cb => sub {
+			$tb_lookup_running = 0;
+			schedule_tb_lookup();
+		});
+	};
+	if ($@) {
+		warn "Error in tablebase lookup: $@";
+
+		# Don't try this one again, but don't block new lookups either.
+		$tb_lookup_running = 0;
 	}
-	return @lines;
+}
+
+sub open_engine {
+	my ($cmdline, $tag, $cb) = @_;
+	return undef if (!defined($cmdline));
+	return Engine->open($cmdline, $tag, $cb);
 }
 
 sub col_letter_to_num {
@@ -1306,8 +1438,12 @@ sub row_letter_to_num {
 	return 7 - (ord(shift) - ord('1'));
 }
 
-sub move_to_uci_notation {
-	my ($from_row, $from_col, $to_row, $to_col, $promo) = @_;
-	$promo //= "";
-	return sprintf("%c%d%c%d%s", ord('a') + $from_col, 8 - $from_row, ord('a') + $to_col, 8 - $to_row, $promo);
+sub parse_uci_move {
+	my $move = shift;
+	my $from_col = col_letter_to_num(substr($move, 0, 1));
+	my $from_row = row_letter_to_num(substr($move, 1, 1));
+	my $to_col   = col_letter_to_num(substr($move, 2, 1));
+	my $to_row   = row_letter_to_num(substr($move, 3, 1));
+	my $promo    = substr($move, 4, 1);
+	return ($from_row, $from_col, $to_row, $to_col, $promo);
 }