Correct independent stock lot activation flow

db/README.md

@@ -18,6 +18,7 @@
 14. `db/migrations/0018_shopify_delta_sync_state.sql`
 15. `db/migrations/0019_allow_multiple_open_stock_lots.sql`
 16. `db/migrations/0020_include_stock_adjustments_in_balance.sql`
+17. `db/migrations/0021_stock_lot_activation_selection.sql`
 
 ## Beispielausfuehrung
 

db/migrations/0021_stock_lot_activation_selection.sql

@@ -0,0 +1,119 @@
+BEGIN;
+
+ALTER TABLE stock_lot
+  ADD COLUMN IF NOT EXISTS next_active BOOLEAN NOT NULL DEFAULT FALSE;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uq_stock_lot_one_next_active_per_product
+  ON stock_lot(product_id)
+  WHERE status = 'open' AND next_active = TRUE;
+
+CREATE OR REPLACE FUNCTION fn_auto_switch_lot_when_depleted()
+RETURNS TRIGGER
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  v_product_id BIGINT;
+  v_open_lot_id BIGINT;
+  v_qualified_count INTEGER;
+  v_current_net NUMERIC;
+  v_event_key TEXT;
+BEGIN
+  SELECT product_id
+  INTO v_product_id
+  FROM stock_lot
+  WHERE id = NEW.lot_id;
+
+  IF NOT EXISTS (
+    SELECT 1 FROM stock_lot WHERE id = NEW.lot_id AND status = 'current'
+  ) THEN
+    RETURN NEW;
+  END IF;
+
+  SELECT qty_net
+  INTO v_current_net
+  FROM v_stock_lot_balance
+  WHERE stock_lot_id = NEW.lot_id;
+
+  IF COALESCE(v_current_net, 0) > 0 THEN
+    RETURN NEW;
+  END IF;
+
+  PERFORM 1
+  FROM stock_lot
+  WHERE product_id = v_product_id
+  FOR UPDATE;
+
+  IF NOT EXISTS (
+    SELECT 1 FROM stock_lot WHERE id = NEW.lot_id AND status = 'current'
+  ) THEN
+    RETURN NEW;
+  END IF;
+
+  SELECT sl.id
+  INTO v_open_lot_id
+  FROM stock_lot sl
+  INNER JOIN v_stock_lot_balance v ON v.stock_lot_id = sl.id
+  WHERE sl.product_id = v_product_id
+    AND sl.status = 'open'
+    AND sl.next_active = TRUE
+    AND NULLIF(TRIM(sl.lot_number), '') IS NOT NULL
+    AND sl.manufacturer_party_id IS NOT NULL
+    AND NULLIF(TRIM(sl.manufacturer_lot_number), '') IS NOT NULL
+    AND sl.mfg_date IS NOT NULL
+    AND sl.expiry_date IS NOT NULL
+    AND sl.purchase_date IS NOT NULL
+    AND v.qty_net > 0
+  LIMIT 1;
+
+  IF v_open_lot_id IS NULL THEN
+    SELECT COUNT(*), MIN(sl.id)
+    INTO v_qualified_count, v_open_lot_id
+    FROM stock_lot sl
+    INNER JOIN v_stock_lot_balance v ON v.stock_lot_id = sl.id
+    WHERE sl.product_id = v_product_id
+      AND sl.status = 'open'
+      AND NULLIF(TRIM(sl.lot_number), '') IS NOT NULL
+      AND sl.manufacturer_party_id IS NOT NULL
+      AND NULLIF(TRIM(sl.manufacturer_lot_number), '') IS NOT NULL
+      AND sl.mfg_date IS NOT NULL
+      AND sl.expiry_date IS NOT NULL
+      AND sl.purchase_date IS NOT NULL
+      AND v.qty_net > 0;
+
+    IF v_qualified_count <> 1 THEN
+      RETURN NEW;
+    END IF;
+
+    UPDATE stock_lot
+    SET next_active = TRUE, updated_at = NOW()
+    WHERE id = v_open_lot_id;
+  END IF;
+
+  UPDATE stock_lot
+  SET status = 'closed', updated_at = NOW()
+  WHERE id = NEW.lot_id;
+
+  UPDATE stock_lot
+  SET status = 'current', next_active = FALSE, updated_at = NOW()
+  WHERE id = v_open_lot_id;
+
+  v_event_key := format('lot.auto_switched:%s:%s', v_product_id, txid_current());
+
+  PERFORM fn_enqueue_event(
+    'lot.auto_switched',
+    v_event_key,
+    'stock_lot',
+    NEW.lot_id::TEXT,
+    jsonb_build_object(
+      'productId', v_product_id,
+      'closedLotId', NEW.lot_id,
+      'newCurrentLotId', v_open_lot_id,
+      'occurredAt', NOW()
+    )
+  );
+
+  RETURN NEW;
+END;
+$$;
+
+COMMIT;