From b92b277c80e007b8aa4e4f2687b2557032ccdcac Mon Sep 17 00:00:00 2001
From: Alex Karle <alex@karle.co>
Date: Fri, 10 Apr 2020 23:07:35 -0400
Subject: [PATCH] Euchre::Dealer: Make dealer track player hands

This is a large conceptual update in that we used to think we wouldn't
care about player hands.

The main motivation for this is to make the server robust to bad
connections. If you close a tab, refresh the page, etc, you'll need to
rejoin. The ONLY way to make this work is to keep track of the hand.

There are a few side benefits to this too:

    1) Simplifies writing clients (they don't need their own
       hand-management)
    2) Verifies clients don't cheat ;)

The actual overhead to make this happen is pretty minimal, so this is a
win all around.
---
 lib/Euchre/Dealer.pm | 47 ++++++++++++++++++++++++++++-------------------
 public/debug.html    | 12 ++++++------
 2 files changed, 34 insertions(+), 25 deletions(-)

diff --git a/lib/Euchre/Dealer.pm b/lib/Euchre/Dealer.pm
index 03da972..3c7ae61 100644
--- a/lib/Euchre/Dealer.pm
+++ b/lib/Euchre/Dealer.pm
@@ -52,7 +52,8 @@ our @EXPORT = qw(
 #           game => reference to current game object,
 #           name => username,
 #           seat => 0-3,
-#           ws   => websocket obj
+#           ws   => websocket obj,
+#           hand => cards in hand
 #       }
 #
 #   The players keyed on ws id is key (pun) because the closure in
@@ -165,10 +166,10 @@ sub join_game {
         # Add player object to Game
         # All players start as spectators and have to take a seat explicitly
         $p->{name} = $msg->{player_name};
+        $p->{hand} = [];
         $p->{game} = $GAMES{$id};
         push @{$GAMES{$id}->{spectators}}, $p;
 
-        # XXX: for fast prototyping we just broadcast gamestate
         broadcast_gamestate($GAMES{$id});
     }
 }
@@ -255,8 +256,7 @@ sub start_new_round {
     broadcast_gamestate($game); # includes trump_nominee
 }
 
-# Hands need to be sent as private messages. For now, we don't
-# keep them in the game state to simplify server logic
+# Deal the hands, leave the messaging to broadcast
 sub deal_players_hands {
     my ($game) = @_;
 
@@ -264,12 +264,7 @@ sub deal_players_hands {
     $game->{trump_nominee} = shift @$kiddeyA;
     for my $p (@{$game->{players}}) {
         my @hand = map { cid_to_name($_) } @{shift @$handsA};
-        $p->{ws}->send({ json =>
-            {
-                msg_type => 'deal',
-                hand => \@hand,
-            }
-        });
+        $p->{hand} = \@hand;
     }
 }
 
@@ -311,6 +306,20 @@ sub play_card {
     my $game = $p->{game};
     my $seat = $p->{seat};
 
+    # Make sure they have the card, and update their hand
+    my $found = 0;
+    for (my $i = 0; $i < scalar @{$p->{hand}}; $i++) {
+        if ($p->{hand}->[$i] eq $msg->{card}) {
+            splice(@{$p->{hand}}, $i, 1);
+            $found = 1;
+            last;
+        }
+    }
+    if (!$found) {
+        send_error($p, "You don't have that card!");
+        return;
+    }
+
     # Update the table and current player
     push @{$game->{table}}, $msg->{card};
     next_turn($game);
@@ -342,7 +351,6 @@ sub play_card {
         }
     }
 
-    # XXX: for fast prototyping we just broadcast gamestate
     broadcast_gamestate($game);
 }
 
@@ -362,11 +370,6 @@ sub signal_game_end {
 sub broadcast_gamestate {
     my ($game) = @_;
 
-    # Get all players in the game
-    my @all_ws = map { $_->{ws} }
-                 grep { defined }
-                 (@{$game->{players}}, @{$game->{spectators}});
-
     # Translate to human readable names for clients
     my @pnames = map { defined($_) ? $_->{name} : 'Empty' } @{$game->{players}};
     my @snames = map { $_->{name} } @{$game->{spectators}};
@@ -380,9 +383,15 @@ sub broadcast_gamestate {
         $msg->{trump_nominee} = cid_to_name($game->{trump_nominee});
     }
 
-    my $json = { msg_type => 'game_state', game => $msg };
-    for my $ws (@all_ws) {
-        $ws->send({ json => $json});
+    for my $p (@{$game->{players}}, @{$game->{spectators}}) {
+        next unless defined $p;
+
+        my $json = {
+            msg_type => 'game_state',
+            game => $msg,
+            hand => $p->{hand},
+        };
+        $p->{ws}->send({ json => $json });
     }
 }
 
diff --git a/public/debug.html b/public/debug.html
index 2783612..23740b9 100644
--- a/public/debug.html
+++ b/public/debug.html
@@ -33,6 +33,12 @@
           vote_trump_suit = msg.game.trump_nominee.substring(1,2);
         }
 
+        document.getElementById('hand').innerHTML = 'HAND: <br>'
+        for (var i = 0; i < msg.hand.length; i++) {
+          var c = msg.hand[i]
+          document.getElementById('hand').innerHTML += '<img onclick="play(' + "'" +  c + "'" + ')" class="card" src="cards/' + c + '.svg">'
+        }
+
         if (msg.game.table.length) {
           document.getElementById('table').innerHTML = ''
           for (var i = 0; i < msg.game.table.length; i++) {
@@ -45,12 +51,6 @@
         document.getElementById('game').innerHTML = gameState
       } else if (msg.msg_type === 'error') {
         document.getElementById('error').innerHTML += msg.msg + '<br>'
-      } else if (msg.msg_type === 'deal') {
-        document.getElementById('hand').innerHTML = 'HAND: <br>'
-        for (var i = 0; i < msg.hand.length; i++) {
-          var c = msg.hand[i]
-          document.getElementById('hand').innerHTML += '<img onclick="play(' + "'" +  c + "'" + ')" class="card" src="cards/' + c + '.svg">'
-        }
       //} else if (msg.msg_type === 'pong') {
       //  console.log('pong!');
       }
--
libgit2 1.1.1