Add tariff_dkk + total_dkk to elprice

Each hourly row now carries the N1 time-of-use tariff (øre/kWh × 10
to match the DKK/MWh unit of price_dkk) and the combined consumer
price (spot + tariff). Existing rows are backfilled in the migration
with a CASE expression mirroring tariffs/tariff-for-hour; new writes
compute it in the controller. API response exposes both fields.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

resources/migrations/20260419020000-add-elprice-tariff-total.down.sql

@@ -0,0 +1,3 @@
+ALTER TABLE elprice DROP COLUMN total_dkk;
+--;;
+ALTER TABLE elprice DROP COLUMN tariff_dkk;

resources/migrations/20260419020000-add-elprice-tariff-total.up.sql

@@ -0,0 +1,21 @@
+ALTER TABLE elprice ADD COLUMN tariff_dkk NUMERIC(10,2);
+--;;
+ALTER TABLE elprice ADD COLUMN total_dkk NUMERIC(10,2);
+--;;
+UPDATE elprice
+   SET tariff_dkk = CASE
+     WHEN EXTRACT(MONTH FROM time_dk) BETWEEN 4 AND 9 THEN
+       CASE
+         WHEN EXTRACT(HOUR FROM time_dk) < 6                              THEN 109.80
+         WHEN EXTRACT(HOUR FROM time_dk) >= 17 AND EXTRACT(HOUR FROM time_dk) < 21 THEN 428.30
+         ELSE                                                                  164.70
+       END
+     ELSE
+       CASE
+         WHEN EXTRACT(HOUR FROM time_dk) < 6                              THEN 109.80
+         WHEN EXTRACT(HOUR FROM time_dk) >= 17 AND EXTRACT(HOUR FROM time_dk) < 21 THEN 988.40
+         ELSE                                                                  329.50
+       END
+   END;
+--;;
+UPDATE elprice SET total_dkk = price_dkk + tariff_dkk WHERE tariff_dkk IS NOT NULL;

resources/queries.sql

@@ -67,14 +67,16 @@ VALUES (:time-start, :hour, :kwh)
 ON CONFLICT (time_start, hour) DO NOTHING;
 
 -- :name insert-elprice! :! :n
--- :doc Insert an hourly el-price row; keep first value on conflict
-INSERT INTO elprice (time_dk, price_area, price_dkk)
-VALUES (:time-dk, :price-area, :price-dkk)
-ON CONFLICT (time_dk, price_area) DO NOTHING;
+-- :doc Upsert an hourly el-price row; refresh tariff/total on conflict
+INSERT INTO elprice (time_dk, price_area, price_dkk, tariff_dkk, total_dkk)
+VALUES (:time-dk, :price-area, :price-dkk, :tariff-dkk, :total-dkk)
+ON CONFLICT (time_dk, price_area) DO UPDATE SET
+  tariff_dkk = EXCLUDED.tariff_dkk,
+  total_dkk  = EXCLUDED.total_dkk;
 
 -- :name get-elprice-for-date :? :*
 -- :doc Hourly prices for a DK local date, both areas
-SELECT time_dk, price_area, price_dkk
+SELECT time_dk, price_area, price_dkk, tariff_dkk, total_dkk
 FROM elprice
 WHERE time_dk::date = :date
 ORDER BY time_dk, price_area;

src/clj/pmagnus/elprice/web/controllers/elprice.clj

@@ -1,7 +1,8 @@
 (ns pmagnus.elprice.web.controllers.elprice
   (:require
     [clojure.data.json :as json]
-    [clojure.tools.logging :as log])
+    [clojure.tools.logging :as log]
+    [pmagnus.elprice.web.controllers.tariffs :as tariffs])
   (:import
     (java.net
       URI
@@ -14,6 +15,7 @@
       Timestamp)
     (java.time
       LocalDate
+      LocalDateTime
       ZoneId)
     (java.time.format
       DateTimeFormatter)))
@@ -68,14 +70,25 @@
     (:records (fetch-json url))))
 
 
+(defn- tariff-dkk-mwh
+  "N1 time-of-use tariff converted from øre/kWh to DKK/MWh (×10)."
+  [^LocalDateTime dt]
+  (* 10.0 (tariffs/tariff-for-hour (.getMonthValue dt) (.getHour dt))))
+
+
 (defn- save-records!
   [query-fn records]
   (doseq [rec records]
     (when-let [dkk (dkk-price (:DayAheadPriceDKK rec) (:DayAheadPriceEUR rec))]
+      (let [ts     (parse-timestamp (:TimeDK rec))
+            tariff (tariff-dkk-mwh (.toLocalDateTime ^Timestamp ts))
+            total  (+ (double dkk) tariff)]
         (query-fn :insert-elprice!
-                {:time-dk    (parse-timestamp (:TimeDK rec))
+                  {:time-dk    ts
                    :price-area (:PriceArea rec)
-                 :price-dkk  dkk}))))
+                   :price-dkk  dkk
+                   :tariff-dkk tariff
+                   :total-dkk  total})))))
 
 
 (defn get-or-fetch!

src/clj/pmagnus/elprice/web/routes/api.clj

@@ -49,7 +49,9 @@
         {:date   date
          :prices (mapv (fn [r] {:time_dk    (str (:time_dk r))
                                 :price_area (:price_area r)
-                                :price_dkk  (:price_dkk r)})
+                                :price_dkk  (:price_dkk r)
+                                :tariff_dkk (:tariff_dkk r)
+                                :total_dkk  (:total_dkk r)})
                        rows)}))
     (catch DateTimeParseException _
       (http-response/bad-request {:error "date must be YYYY-MM-DD"}))))