From 3b70d2a0bcd5b89df940495f1431f66eabe0a21e Mon Sep 17 00:00:00 2001
From: Moritz Bunkus <m.bunkus@linet-services.de>
Date: Wed, 17 Nov 2010 10:38:00 +0100
Subject: [PATCH] Helfermodul zur Aktualisierung von Preisen in Belegen

---
 SL/DB/Helper/PriceUpdater.pm | 111 +++++++++++++++++++++++++++++++++++
 1 file changed, 111 insertions(+)
 create mode 100644 SL/DB/Helper/PriceUpdater.pm

diff --git a/SL/DB/Helper/PriceUpdater.pm b/SL/DB/Helper/PriceUpdater.pm
new file mode 100644
index 000000000..a927f0e19
--- /dev/null
+++ b/SL/DB/Helper/PriceUpdater.pm
@@ -0,0 +1,111 @@
+package SL::DB::Helper::PriceUpdater;
+
+use strict;
+
+use parent qw(Exporter);
+our @EXPORT = qw(update_prices);
+
+use Carp;
+
+sub update_prices {
+  my $self   = shift;
+  my %params = @_;
+
+  croak('Missing parameters amount/percent') unless $params{amount} || $params{percent};
+
+  my @prices = ref $params{prices} eq 'ARRAY' ? @{ $params{prices} } : ( $params{prices} || 'sellprice' );
+
+  foreach my $field (@prices) {
+    my $rounding_error = 0;
+
+    foreach my $item (@{ $self->items }) {
+      my $new_price;
+      if ($params{amount}) {
+        $new_price = $item->$field + $params{amount}        + $rounding_error;
+      } else {
+        $new_price = $item->$field * $params{percent} / 100 + $rounding_error;
+      }
+
+      $item->$field($::form->round_amount($new_price, 2));
+      $rounding_error += $new_price - $item->$field;
+
+      _dbg("new_price $new_price new_price_no_err " . ($new_price - $rounding_error) . " rounded " . $item->$field .
+           " error_old " . ($rounding_error - $new_price + $item->$field) . " error_new $rounding_error");
+    }
+  }
+
+  return $self->calculate_prices_and_taxes if $params{calculate};
+  return $self;
+}
+
+sub _dbg {
+  # $::lxdebug->message(0, __PACKAGE__ . ': ' . join(' ', @_));
+}
+
+1;
+
+__END__
+
+=encoding utf8
+
+=head1 NAME
+
+SL::DB::Helper::PriceUpdater - Mixin for updating all prices by a fixed amount or by a percentage
+
+=head1 FUNCTIONS
+
+=over 4
+
+=item C<update_prices %params>
+
+Updates the prices of all items as returned by the function C<items>
+provided by the mixing class.
+
+Supported arguments via C<%params> are:
+
+=over 2
+
+=item C<amount>
+
+Absolute amount to add or subtract. Either C<amount> or C<percent>
+must be given. Resulting prices are rounded to two significant places.
+
+=item C<percent>
+
+Percentage to set the prices to (with 100 meaning "no
+change"). Resulting prices are rounded to two significant
+places. Rounding errors are carried over to the next item.
+
+Either C<amount> or C<percent> must be given.
+
+=item C<prices>
+
+A string or an array of strings naming the prices to update. If
+missing only the C<sellprice> field will be updated.
+
+=item C<calculate>
+
+If trueish the all prices, taxes and amounts are re-calculated by
+calling
+L<SL::DB::Helper::PriceTaxCalculator::calculate_prices_and_taxes>.
+Returns that function's result.
+
+=back
+
+Returns C<$self> unless C<$params{calculate}> is trueish.
+
+=back
+
+=head1 EXPORTS
+
+This mixin exports the function L</update_prices>.
+
+=head1 BUGS
+
+Nothing here yet.
+
+=head1 AUTHOR
+
+Moritz Bunkus E<lt>m.bunkus@linet-services.deE<gt>
+
+=cut
-- 
2.20.1