Improve delivery validation: StockArticles must not be associated more than once

app/helpers/application_helper.rb

@@ -158,5 +158,13 @@ module ApplicationHelper
     end
     flash_messages.join("\n").html_safe
   end
+  
+  # render base errors in a form after failed validation
+  # http://railsapps.github.io/twitter-bootstrap-rails.html
+  def base_errors resource
+    return '' if (resource.errors.empty?) or (resource.errors[:base].empty?)
+    messages = resource.errors[:base].map { |msg| content_tag(:li, msg) }.join
+    render :partial => 'shared/base_errors', :locals => {:error_messages => messages}
+  end
 
 end

app/models/delivery.rb

@@ -10,6 +10,7 @@ class Delivery < ActiveRecord::Base
   scope :recent, :order => 'created_at DESC', :limit => 10
 
   validates_presence_of :supplier_id, :delivered_on
+  validate :stock_articles_must_be_unique
 
   accepts_nested_attributes_for :stock_changes, :allow_destroy => :true
 
@@ -23,6 +24,14 @@ class Delivery < ActiveRecord::Base
     self.stock_changes.map{|stock_change| stock_change.stock_article.id}.include? article.id
   end
   
+  protected
+  
+  def stock_articles_must_be_unique
+    unless stock_changes.reject{|sc| sc.marked_for_destruction?}.map {|sc| sc.stock_article.id}.uniq!.nil?
+      errors.add(:base, I18n.t('model.delivery.each_stock_article_must_be_unique'))
+    end
+  end
+  
 end
 
 

app/views/deliveries/_form.html.haml

@@ -6,14 +6,15 @@
         
         var stock_change = $(this).closest('tr');
         stock_change.hide(); // do not remove (to ensure destruction)
-        unmark_article_unavailable_for_delivery( stock_change.data('id') );
+        stock_change.removeAttr('id'); // remove id to allow re-adding
+        mark_article_for_delivery( stock_change.data('id') );
         return false;
       });
 
       $('.remove_new_stock_change').live('click', function() {
         var stock_change = $(this).closest('tr');
         stock_change.remove();
-        unmark_article_unavailable_for_delivery( stock_change.data('id') );
+        mark_article_for_delivery( stock_change.data('id') );
         return false;
       })
       
@@ -62,23 +63,26 @@
       });
     });
     
-    function mark_article_unavailable_for_delivery(stock_article_id) {
+    function mark_article_for_delivery(stock_article_id) {
       var articleTr = $('#stock_article_' + stock_article_id);
-      articleTr.addClass('unavailable');
-      $('.button-add-stock-change', articleTr).attr('disabled', 'disabled');
+      if( is_article_available_for_delivery(stock_article_id) ) {
+        articleTr.removeClass('unavailable');
+        $('.button-add-stock-change', articleTr).removeAttr('disabled');
+      }
+      else {
+        articleTr.addClass('unavailable');
+        $('.button-add-stock-change', articleTr).attr('disabled', 'disabled');
+      }
     }
-    function unmark_article_unavailable_for_delivery(stock_article_id) {
-      var articleTr = $('#stock_article_' + stock_article_id);
-      articleTr.removeClass('unavailable');
-      $('.button-add-stock-change', articleTr).removeAttr('disabled');
-    }
-    function is_article_unavailable_for_delivery(stock_article_id) {
-      var articleTr = $('#stock_article_' + stock_article_id);
-      return articleTr.hasClass('unavailable');
+    function is_article_available_for_delivery(stock_article_id) {
+      return ( 0 == $('#stock_change_stock_article_' + stock_article_id).length );
     }
 
 = simple_form_for [@supplier, @delivery], validate: true do |f|
-  = f.hidden_field :supplier_id
+  = f.error_notification
+  = base_errors f.object
+  = f.association :supplier, :as => :hidden
+  
   %h2= t '.title_select_stock_articles'
   .well.well-small
     .btn-toolbar

app/views/deliveries/add_stock_change.js.erb

@@ -1,13 +1,5 @@
 (function(w) {
-  if(is_article_unavailable_for_delivery(<%= @stock_change.stock_article.id %>)) {
-    return false;
-  }
-  
-  mark_article_unavailable_for_delivery(<%= @stock_change.stock_article.id %>);
-  
-  var quantity = w.prompt('<%= j(t('.how_many_units', :unit => @stock_change.stock_article.unit, :name => @stock_change.stock_article.name)) %>'); <%# how to properly escape here? %>
-  if(null === quantity) {
-    unmark_article_unavailable_for_delivery(<%= @stock_change.stock_article.id %>); // think wisely before changing this: What about double clicks on "deliver" button?
+  if(!is_article_available_for_delivery(<%= @stock_change.stock_article.id %>)) {
     return false;
   }
   
@@ -17,8 +9,16 @@
     '<%= j(render(:partial => 'stock_change', :locals => {:stock_change => @stock_change})) %>'
   ).addClass('success');
   
+  $('#stock_changes').append(stock_change);
+  mark_article_for_delivery(<%= @stock_change.stock_article.id %>);
+  updateSort('#stock_changes');
+  
+  var quantity = w.prompt('<%= j(t('.how_many_units', :unit => @stock_change.stock_article.unit, :name => @stock_change.stock_article.name)) %>'); <%# how to properly escape here? %>
+  if(null === quantity) {
+    stock_change.remove();
+    mark_article_for_delivery(<%= @stock_change.stock_article.id %>);
+    return false;
+  }
   $('input.stock-change-quantity', stock_change).val(quantity);
   
-  $('#stock_changes').append(stock_change);
-  updateSort('#stock_changes');
 })(window);

app/views/shared/_base_errors.haml

@@ -0,0 +1,5 @@
+.alert.alert-error.alert-block
+  %a.close{:href => '#', :data => {:dismiss => 'alert'}}
+    = t('ui.marks.close').html_safe
+  %ul
+    = error_messages.html_safe

config/locales/de.yml

@@ -1163,6 +1163,8 @@ de:
       subject: ! 'Betreff:'
       title: Nachricht anzeigen
   model:
+    delivery:
+      each_stock_article_must_be_unique: Lieferung darf jeden Lagerartikel höchstens einmal auflisten.
     membership:
       no_admin_delete: Mitgliedschaft kann nicht beendet werden. Du bist die letzte Administratorin
     order_article:

config/locales/en.yml

@@ -1166,6 +1166,8 @@ en:
       subject: ! 'Subject:'
       title: Show message
   model:
+    delivery:
+      each_stock_article_must_be_unique: Each stock article must not be listed more than once.
     membership:
       no_admin_delete: Membership can not be withdrawn as you are the last administrator.
     order_article: