give partially unused order articles a distinct colour

app/assets/javascripts/ordering.js

@@ -119,7 +119,7 @@ function update(item, quantity, tolerance) {
 
     // update missing units
     var missing_units = unit[item] - (((quantityOthers[item] + Number(quantity)) % unit[item]) + Number(tolerance) + toleranceOthers[item])
-    if (missing_units < 0) {
+    if (missing_units < 0 || missing_units == unit[item]) {
         missing_units = 0;
     }
     $('#missing_units_' + item).html(String(missing_units));

app/assets/stylesheets/bootstrap_and_overrides.css.less

@@ -38,6 +38,7 @@ body {
 
 // article status
 @articleUsedColor: green;
+@articlePartusedColor: #d50;
 @articleUnusedColor: red;
 @articleUnavailColor: #999;
 @articleUpdatedColor: #468847;
@@ -158,6 +159,9 @@ table {
 .unused {
   color: @articleUnusedColor;
 }
+.partused {
+  color: @articlePartusedColor;
+}
 
 #order-footer, .article-info {
   text-align: left;
@@ -253,6 +257,7 @@ td.symbol, th.symbol {
 .symbol              { color: tint(@textColor, @nonessentialDim); }
 .used        .symbol { color: tint(@articleUsedColor, @nonessentialDim); }
 .unused      .symbol { color: tint(@articleUnusedColor, @nonessentialDim); }
+.partused    .symbol { color: tint(@articlePartusedColor, @nonessentialDim); }
 .unavailable .symbol { color: @articleUnavailColor; }
 
 // hide symbols completely on small screens to save space
@@ -359,6 +364,7 @@ i.package.icon-only {
 .package              { color: tint(@textColor, @nonessentialDim); }
 .used        .package { color: tint(@articleUsedColor, @nonessentialDim); }
 .unused      .package { color: tint(@articleUnusedColor, @nonessentialDim); }
+.partused    .package { color: tint(@articlePartusedColor, @nonessentialDim); }
 .unavailable .package { color: @articleUnavailColor; }
 
 // very small inputs - need !important for responsive selectors

app/helpers/orders_helper.rb

@@ -125,10 +125,14 @@ module OrdersHelper
   end
 
   # @param order_article [OrderArticle]
-  # @return [String] CSS class for +OrderArticle+ in table for admins
+  # @return [String] CSS class for +OrderArticle+ in table for admins (+used+, +partused+, +unused+ or +unavailable+).
   def order_article_class(order_article)
     if order_article.units > 0
-      'used'
+      if order_article.missing_units == 0
+        'used'
+      else
+        'partused'
+      end
     elsif order_article.quantity > 0
       'unused'
     else

app/models/order_article.rb

@@ -184,10 +184,11 @@ class OrderArticle < ActiveRecord::Base
     @update_global_price = (value == true or value == '1') ?  true : false
   end
 
-  # Units missing for the next full unit_quantity of the article
+  # @return [Number] Units missing for the last +unit_quantity+ of the article.
   def missing_units
     units = article.unit_quantity - ((quantity  % article.unit_quantity) + tolerance)
     units = 0 if units < 0
+    units = 0 if units == article.unit_quantity
     units
   end