From e2463128a74fd2007dfbb9807cd3b2ff4b7f97d9 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ian@liberator.relativity.greenend.org.uk>
Date: Sun, 23 Aug 2009 11:22:29 +0100
Subject: [PATCH] Runs glpsol, calculates optimal solution

---
 yarrg/web/routetrade | 81 +++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 77 insertions(+), 4 deletions(-)

diff --git a/yarrg/web/routetrade b/yarrg/web/routetrade
index 1924503..a52531c 100644
--- a/yarrg/web/routetrade
+++ b/yarrg/web/routetrade
@@ -55,18 +55,38 @@ my $sd_condition= sub {
 	}
 };
 
+my %islandpair;
+# $islandpair{$a,$b}= [ $start_island_ix, $end_island_ix ]
+
+my $specific= !grep { !defined $_ } @islandids;
+my $confusing= 0;
+
 foreach my $src_i (0..$#islandids) {
+	my $src_isle= $islandids[$src_i];
 	my $src_cond= $sd_condition->('sell',$src_i);
 	my @dst_conds;
 	foreach my $dst_i ($src_i..$#islandids) {
+		my $dst_isle= $islandids[$dst_i];
 		my $dst_cond= $sd_condition->('buy',$dst_i);
-		if ($dst_i==$src_i and !defined $islandids[$src_i]) {
+		if ($dst_i==$src_i and !defined $src_isle) {
 			# we always want arbitrage, but mentioning an arch
 			# once shouldn't produce intra-arch trades
 			$dst_cond=
 				"($dst_cond AND sell.islandid = buy.islandid)";
 		}
 		push @dst_conds, $dst_cond;
+
+		if ($specific && !$confusing &&
+		    # With a circular route, do not carry goods round the loop
+		    !($src_i==0 && $dst_i==$#islandids &&
+		      $src_isle == $islandids[$dst_i])) {
+			if ($islandpair{$src_isle,$dst_isle}) {
+				$confusing= 1;
+			} else {
+				$islandpair{$src_isle,$dst_isle}=
+					[ $src_i, $dst_i ];
+			}
+		}
 	}
 	push @flow_conds, "$src_cond AND (
 			".join("
@@ -85,8 +105,8 @@ my $stmt= "
 		sum(buy.qty) 					dst_qty,
 		commods.commodname				commodname,
 		commods.commodid				commodid,
-		commods.unitmass				mass,
-		commods.unitvolume				volume,
+		commods.unitmass				unitmass,
+		commods.unitvolume				unitvolume,
 		buy.price - sell.price				unitprofit,
 		min(sell.qty,buy.qty)				tqty,
 		min(sell.qty,buy.qty) * (buy.price-sell.price)	profit
@@ -130,6 +150,22 @@ my @flows;
 <& dumpqueryresults:end &>
 % }
 
+% if (!$specific || $confusing || @islandids<=1) {
+
+<p>
+% if (@islandids<=1) {
+Route is trivial.
+% }
+% if (!$specific) {
+Route contains archipelago(es), not just specific islands.
+% }
+% if ($confusing) {
+Route is complex - it visits the same island several times
+and isn't a simple loop.
+% }
+Therefore, optimal trade pattern not calculated.
+
+% } else { # ========== OPTMISATION ==========
 <%perl>
 
 my $cplex= "
@@ -170,13 +206,50 @@ Bounds
 
 End
 ";
-# glpsol --cpxlp /dev/stdin <t.cplex -o /dev/stdout
 
+if ($qa->{'debug'}) {
 </%perl>
 <pre>
 <% $cplex |h %>
 </pre>
+<%perl>
+}
+
+{
+	my $input= pipethrough_prep();
+	print $input $cplex or die $!;
+	my $output= pipethrough_run_along($input, undef, 'glpsol',
+		qw(glpsol --cpxlp /dev/stdin -o /dev/stdout));
+	print "<pre>\n" if $qa->{'debug'};
+	my $found_section= 0;
+	while (<$output>) {
+		print encode_entities($_) if $qa->{'debug'};
+		if (m/^\s*No\.\s+Column name\s+St\s+Activity\s/) {
+			die if $found_section>0;
+			$found_section= 1;
+			next;
+		}
+		next unless $found_section==1;
+		next if m/^[- ]+$/;
+		if (!/\S/) {
+			$found_section= 2;
+			next;
+		}
+		m/^\s*\d+\s+f(\d+)\s+\S+\s+(\d+)\s/ or die "$_ ?";
+		die if $1 >= @flows;
+		$flows[$1]{Optimal}= $2;
+	}
+	print "</pre>\n" if $qa->{'debug'};
+	pipethrough_run_finish($output, 'glpsol');
+	die unless $found_section;
+};
+
+print join ' ', map { $_->{Optimal} } @flows;
+
+</%perl>
+% } # ========== OPTIMISATION ==========
 
 <%init>
 use CommodsWeb;
+use Commods;
 </%init>
-- 
2.30.2