Add tag_rules logic to main query before pagination

app/services/order_cycle_distributed_products.rb

@@ -2,9 +2,10 @@
 # The stock-checking includes on_demand and stock level overrides from variant_overrides.
 
 class OrderCycleDistributedProducts
-  def initialize(distributor, order_cycle)
+  def initialize(distributor, order_cycle, customer)
     @distributor = distributor
     @order_cycle = order_cycle
+    @customer = customer
   end
 
   def products_relation
@@ -12,26 +13,97 @@ class OrderCycleDistributedProducts
   end
 
   def variants_relation
-    @order_cycle.
-      variants_distributed_by(@distributor).
+    order_cycle.
+      variants_distributed_by(distributor).
       merge(stocked_variants_and_overrides)
   end
 
   private
 
+  attr_reader :distributor, :order_cycle, :customer
+
   def stocked_products
-    @order_cycle.
-      variants_distributed_by(@distributor).
+    order_cycle.
+      variants_distributed_by(distributor).
       merge(stocked_variants_and_overrides).
       select("DISTINCT spree_variants.product_id")
   end
 
   def stocked_variants_and_overrides
-    Spree::Variant.
+    stocked_variants = Spree::Variant.
       joins("LEFT OUTER JOIN variant_overrides ON variant_overrides.variant_id = spree_variants.id
-            AND variant_overrides.hub_id = #{@distributor.id}").
+            AND variant_overrides.hub_id = #{distributor.id}").
       joins(:stock_items).
       where(query_stock_with_overrides)
+
+    if distributor_rules.any?
+      stocked_variants = apply_tag_rules(stocked_variants)
+    end
+
+    stocked_variants
+  end
+
+  def apply_tag_rules(stocked_variants)
+    stocked_variants.where(query_with_tag_rules)
+  end
+
+  def distributor_rules
+    @distributor_rules ||= TagRule::FilterProducts.prioritised.for(distributor)
+  end
+
+  def customer_tag_list
+    customer.andand.tag_list || []
+  end
+
+  def default_rule_tags
+    default_rules.map(&:preferred_variant_tags)
+  end
+
+  def hide_rule_tags
+    hide_rules.map(&:preferred_variant_tags)
+  end
+
+  def show_rule_tags
+    show_rules.map(&:preferred_variant_tags)
+  end
+
+  def overrides_to_hide
+    @overrides_to_hide = VariantOverride.where(hub_id: distributor.id).
+      tagged_with(default_rule_tags + hide_rule_tags, any: true).
+      pluck(:id)
+  end
+
+  def overrides_to_show
+    @overrides_to_show = VariantOverride.where(hub_id: distributor.id).
+      tagged_with(show_rule_tags, any: true).
+      pluck(:id)
+  end
+
+  def customer_applicable_rules
+    # Rules which apply specifically to the current customer
+    @customer_applicable_rules ||= non_default_rules.select{ |rule| customer_tagged?(rule) }
+  end
+
+  def default_rules
+    # These rules hide a variant_override with tag X
+    distributor_rules.select(&:is_default?)
+  end
+
+  def non_default_rules
+    # These rules show or hide a variant_override with tag X for customer with tag Y
+    distributor_rules.reject(&:is_default?)
+  end
+
+  def hide_rules
+    @hide_rules ||= customer_applicable_rules.select{ |rule| rule.preferred_matched_variants_visibility == 'hidden'}
+  end
+
+  def show_rules
+    customer_applicable_rules - hide_rules
+  end
+
+  def customer_tagged?(rule)
+    customer_tag_list.include? rule.preferred_customer_tags
   end
 
   def query_stock_with_overrides
@@ -42,6 +114,22 @@ class OrderCycleDistributedProducts
                                       AND #{variant_not_on_demand} AND #{variant_in_stock} ) )"
   end
 
+  def query_with_tag_rules
+    "#{variant_not_overriden} OR ( #{variant_overriden}
+                                   AND ( #{override_not_hidden_by_rule}
+                                   OR #{override_shown_by_rule} ) )"
+  end
+
+  def override_not_hidden_by_rule
+    return "FALSE" unless overrides_to_hide.any?
+    "variant_overrides.id NOT IN (#{overrides_to_hide.join(',')})"
+  end
+
+  def override_shown_by_rule
+    return "FALSE" unless overrides_to_show.any?
+    "variant_overrides.id IN (#{overrides_to_show.join(',')})"
+  end
+
   def variant_not_overriden
     "variant_overrides.id IS NULL"
   end