WIP: Add lowest_value_test to WeightedAverage

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Resource_zGetAssetPrice.sql

@@ -7,13 +7,16 @@ since they rely on the same kind of "split by period" model.
 First split timeframe into Year (or Month) periods, and fold all movements
 during each period.
 Then perform a weighted average over all periods.
+
+Parameter lowest_value_test compares latest price and WeightedAverage average price and takes the
+smallest one.
 */
 
 set @total_asset_price=0.0, @total_quantity=0.0
 <dtml-var sql_delimiter>
 select
     byperiod.*,
-    (@unit_price:=(@total_asset_price+incoming_total_price)/(@total_quantity+incoming_total_quantity)) as unit_price,
+    (@unit_price:=MIN((@total_asset_price+incoming_total_price)/(@total_quantity+incoming_total_quantity)), last_price) as unit_price,
     (@total_asset_price:=
         @total_asset_price +
         incoming_total_price +
@@ -27,11 +30,21 @@ from
             SUM(IF(quantity>0, total_price, 0)) as incoming_total_price,
             SUM(IF(quantity>0, quantity, 0)) as incoming_total_quantity,
             SUM(IF(quantity>0, 0, quantity)) as outgoing_total_quantity,
-            SUM(quantity) as quantity_diff
+            SUM(quantity) as quantity_diff,
+            MAX(last_price) as last_price
         from
-            stock, catalog
-        where
-          <dtml-var where_expression>
+            (
+                select
+                    date,
+                    total_price,
+                    quantity,
+                    IF(date=MAX(IF(quantity>0, date, 0)) OVER (PARTITION BY year(date)), total_price, 0) as last_price
+                    <dtml-if "'Monthly' in valuation_method">, IF(date=MAX(IF(quantity>0, date, 0)) OVER (PARTITION BY month(date)), total_price, 0) as last_price</dtml-if>
+                from
+                    stock, catalog
+                where
+                  <dtml-var where_expression>
+            ) as last_price_per_period
         group by
             d_year<dtml-if "'Monthly' in valuation_method">, d_month</dtml-if>
         order by