From 5cf50f0adfc45ec14102c3910dd2beffe56d6c9a Mon Sep 17 00:00:00 2001
From: luisramos0 <luisramos0@gmail.com>
Date: Mon, 18 Nov 2019 12:05:19 +0000
Subject: [PATCH] Convert the manipulation of arrays into active record
 relations: let the DB do the matching job

---
 app/services/exchange_products_renderer.rb | 53 ++++++++++------------
 1 file changed, 23 insertions(+), 30 deletions(-)

diff --git a/app/services/exchange_products_renderer.rb b/app/services/exchange_products_renderer.rb
index ffdfd1975c..c4e9a1f77e 100644
--- a/app/services/exchange_products_renderer.rb
+++ b/app/services/exchange_products_renderer.rb
@@ -15,43 +15,33 @@ class ExchangeProductsRenderer
   private
 
   def products_for_incoming_exchange(enterprise)
-    supplied_products(enterprise)
+    supplied_products(enterprise.id)
   end
 
-  def supplied_products(enterprise)
+  def supplied_products(enterprises_query_matcher)
+    products_relation = Spree::Product.where(supplier_id: enterprises_query_matcher)
+
     if @order_cycle.present? &&
        @order_cycle.prefers_product_selection_from_coordinator_inventory_only?
-      enterprise.supplied_products.visible_for(@order_cycle.coordinator)
-    else
-      enterprise.supplied_products
+      products_relation = products_relation.visible_for(@order_cycle.coordinator)
     end
+
+    products_relation
   end
 
   def products_for_outgoing_exchange
-    products = []
-    enterprises_for_outgoing_exchange.each do |enterprise|
-      products.push( *supplied_products(enterprise).to_a )
-
-      products.each do |product|
-        unless product_supplied_to_order_cycle?(product)
-          products.delete(product)
-        end
-      end
-    end
-    products
-  end
-
-  def product_supplied_to_order_cycle?(product)
-    (product.variants.map(&:id) & incoming_exchanges_variants).any?
+    supplied_products(enterprises_for_outgoing_exchange.select(:id)).
+      includes(:variants).
+      where("spree_variants.id": incoming_exchanges_variants)
   end
 
   def incoming_exchanges_variants
     return @incoming_exchanges_variants if @incoming_exchanges_variants.present?
 
     @incoming_exchanges_variants = []
-    visible_incoming_exchanges.each do |exchange|
+    visible_incoming_exchanges.each do |incoming_exchange|
       @incoming_exchanges_variants.push(
-        *exchange.variants.merge(visible_incoming_variants(exchange)).map(&:id).to_a
+        *incoming_exchange.variants.merge(visible_incoming_variants(incoming_exchange.sender)).map(&:id).to_a
       )
     end
     @incoming_exchanges_variants
@@ -65,17 +55,20 @@ class ExchangeProductsRenderer
       incoming
   end
 
-  def visible_incoming_variants(exchange)
-    if exchange.order_cycle.prefers_product_selection_from_coordinator_inventory_only?
-      permitted_incoming_variants(exchange).visible_for(exchange.order_cycle.coordinator)
-    else
-      permitted_incoming_variants(exchange)
+  def visible_incoming_variants(incoming_exchange_sender)
+    variants_relation = permitted_incoming_variants(incoming_exchange_sender)
+
+    if @order_cycle.prefers_product_selection_from_coordinator_inventory_only?
+      variants_relation = variants_relation.visible_for(@order_cycle.coordinator)
     end
+
+    variants_relation
   end
 
-  def permitted_incoming_variants(exchange)
-    OpenFoodNetwork::OrderCyclePermissions.new(@user, exchange.order_cycle).
-      visible_variants_for_incoming_exchanges_from(exchange.sender)
+  def permitted_incoming_variants(incoming_exchange_sender)
+    OpenFoodNetwork::OrderCyclePermissions.
+      new(@user, @order_cycle).
+      visible_variants_for_incoming_exchanges_from(incoming_exchange_sender)
   end
 
   def enterprises_for_outgoing_exchange