From ccae71021a1b4d657c47fbee01f922d15ead00a2 Mon Sep 17 00:00:00 2001
From: Juerd Waalboer <juerd@tnx.nl>
Date: Sat, 11 Jun 2022 16:58:20 +0200
Subject: [PATCH] Get 'cash' working again

Now implemented via a hidden user called '-cash'.

This also introduces the concept of hidden accounts, that begin with '+' or
'-', for result accounts and balance accounts. Future versions can further
use this for more detailed bookkeeping. The idea behind the sign is that
'-' accounts should be inverted to get the intuitive value. So if the account
'-cash' has -13.37, that means there should be +13.37 in the cash box (or,
well, once the rest of this is implemented and the initial values are then set
correctly.)
---
 lib/RevBank/Cart.pm     | 7 +++++++
 lib/RevBank/Messages.pm | 6 ++++++
 lib/RevBank/Users.pm    | 9 +++++++--
 plugins/adduser         | 3 +++
 plugins/stock           | 3 +--
 revbank.accounts        | 3 +++
 6 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/lib/RevBank/Cart.pm b/lib/RevBank/Cart.pm
index 817bbf0..2ff8d9e 100644
--- a/lib/RevBank/Cart.pm
+++ b/lib/RevBank/Cart.pm
@@ -8,6 +8,7 @@ no warnings qw(experimental::signatures);
 use Carp ();
 use List::Util ();
 use RevBank::Global;
+use RevBank::Users;
 use RevBank::Cart::Entry;
 
 sub new($class) {
@@ -65,6 +66,12 @@ sub checkout($self, $user) {
         return;
     }
 
+    if ($user =~ /^[-+]/) {
+        # Hidden internal accounts
+        my $canonical = RevBank::Users::parse_user($user);
+        $user = $canonical // RevBank::Users::create($user);
+    }
+
     my $entries = $self->{entries};
 
     my %deltas;
diff --git a/lib/RevBank/Messages.pm b/lib/RevBank/Messages.pm
index 5f2c692..af39c49 100644
--- a/lib/RevBank/Messages.pm
+++ b/lib/RevBank/Messages.pm
@@ -13,8 +13,10 @@ use base 'RevBank::Plugin';
 
 BEGIN {
     RevBank::Plugins::register("RevBank::Messages");
+    *hidden = \&RevBank::Users::is_hidden;
 }
 
+
 sub command { return NEXT; }
 sub id { 'built in messages' }
 
@@ -53,6 +55,8 @@ sub hook_reject($class, $plugin, $reason, $abort, @) {
 }
 
 sub hook_user_balance($class, $username, $old, $delta, $new, @) {
+    return if hidden $username;
+
     my $sign = $delta->cents >= 0 ? '+' : '-';
     my $rood = $new->cents < 0 ? '31;' : '';
     my $abs  = $delta->abs;
@@ -63,6 +67,8 @@ sub hook_user_balance($class, $username, $old, $delta, $new, @) {
 }
 
 sub hook_user_created($class, $username, @) {
+    return if hidden $username;
+
     say "New account '$username' created.";
 }
 
diff --git a/lib/RevBank/Users.pm b/lib/RevBank/Users.pm
index eb33f80..35fe23b 100644
--- a/lib/RevBank/Users.pm
+++ b/lib/RevBank/Users.pm
@@ -36,13 +36,14 @@ sub create($username) {
     print {$fh} "$username 0.00 $now\n" or die $!;
     close $fh or die $!;
     RevBank::Plugins::call_hooks("user_created", $username);
+    return $username;
 }
 
 sub update($username, $delta, $transaction_id) {
     open my $in,  'revbank.accounts' or die $!;
     open my $out, ">.revbank.$$" or die $!;
-    my $old;
-    my $new;
+    my $old = RevBank::Amount->new(0);
+    my $new = RevBank::Amount->new(0);
     while (defined (my $line = readline $in)) {
         my @a = split " ", $line;
         if (lc $a[0] eq lc $username) {
@@ -82,6 +83,10 @@ sub parse_user($username) {
     return $users->{ lc $username }->[0];
 }
 
+sub is_hidden($username) {
+    return $username =~ /^[-+]/;
+}
+
 1;
 
 
diff --git a/plugins/adduser b/plugins/adduser
index 2a5a592..52234de 100644
--- a/plugins/adduser
+++ b/plugins/adduser
@@ -16,6 +16,9 @@ sub username($self, $cart, $name, @) {
     return REJECT, "Sorry, whitespace is not allowed."
         if $name =~ /\s/;
 
+    return REJECT, "Sorry, invalid first character."
+        if $name =~ /^[-+*]/;
+
     return REJECT, "That's too numeric to be a user name."
         if defined parse_amount($name);
 
diff --git a/plugins/stock b/plugins/stock
index 53c7f15..9f2b5f3 100644
--- a/plugins/stock
+++ b/plugins/stock
@@ -5,8 +5,7 @@ HELP1 "cash" => "Checkout without a user account";
 sub command :Tab(cash) ($self, $cart, $command, @) {
     return NEXT if $command ne 'cash';
 
-    call_hooks("checkout", $cart, 'cash', 0);  # Fake checkout
-    $cart->empty;
+    $cart->checkout('-cash');
 
     return ACCEPT;
 }
diff --git a/revbank.accounts b/revbank.accounts
index 7b3c499..5f92fc7 100644
--- a/revbank.accounts
+++ b/revbank.accounts
@@ -1,2 +1,5 @@
 juerd              +163.48 2022-06-04_02:19:56 +@2021-12-03_18:27:54
 bla                 -36.00 2022-01-19_17:11:25 -@2022-01-19_17:00:43
+ 0.00 2022-06-11_16:47:33
+fooooo 0.00 2022-06-11_16:52:48
+-cash                -0.50 2022-06-11_16:56:36 -@2022-06-11_16:56:36