allow to edit GroupOrderArticle result from orders screen

Conflicts:
	app/assets/javascripts/application.js

app/controllers/group_order_articles_controller.rb

@@ -0,0 +1,75 @@
+class GroupOrderArticlesController < ApplicationController
+
+  before_filter :authenticate_finance
+  before_filter :find_group_order_article, except: [:new, :create]
+
+  layout false  # We only use this controller to server js snippets, no need for layout rendering
+
+  def new
+    @order_article = OrderArticle.find(params[:order_article_id])
+    @group_order_article = GroupOrderArticle.new(order_article: @order_article)
+  end
+
+  def create
+    # XXX when ordergroup_id appears before order_article_id in the parameters, you
+    #     can get `NoMethodError - undefined method 'order_id' for nil:NilClass`
+    @group_order_article = GroupOrderArticle.new(params[:group_order_article])
+    @order_article = @group_order_article.order_article
+
+    # As we hide group_order_articles with a result of 0, we should not complain, when an existing group_order_article is found
+    goa = GroupOrderArticle.where(group_order_id: @group_order_article.group_order_id,
+                                  order_article_id: @order_article.id).first
+
+    if goa and goa.update_attributes(params[:group_order_article])
+      @group_order_article = goa
+
+      update_summaries(@group_order_article)
+      render :create
+
+    elsif @group_order_article.save
+      update_summaries(@group_order_article)
+      render :create
+
+    else  # Validation failed, show form
+      render :new
+    end
+  end
+
+  def update
+    if params[:delta]
+      @group_order_article.update_attribute :result, [@group_order_article.result + params[:delta].to_f, 0].max
+    else
+      @group_order_article.update_attributes(params[:group_order_article])
+    end
+
+    update_summaries(@group_order_article)
+
+    render :update
+  end
+
+  def destroy
+    # only destroy if quantity and tolerance was zero already, so that we don't
+    # lose what the user ordered, if any
+    if @group_order_article.quantity > 0 or @group_order_article.tolerance >0
+      @group_order_article.update_attribute(:result, 0)
+    else
+      @group_order_article.destroy
+    end
+    update_summaries(@group_order_article)
+
+    render :update
+  end
+
+  protected
+
+  def update_summaries(group_order_article)
+    # Update the price attribute of new GroupOrder
+    group_order_article.group_order.update_price!
+    # Update units_to_order of order_article
+    group_order_article.order_article.update_results! if group_order_article.order_article.article.is_a?(StockArticle)
+  end
+
+  def find_group_order_article
+    @group_order_article = GroupOrderArticle.find(params[:id])
+  end
+end