find a solution for two best orders

model.py

@@ -564,6 +564,17 @@ def delete_order(order_id):
         ''', (order_id,))
 
 
+def current_value(ownable_id):
+    connect()
+    cursor.execute('''SELECT price 
+                      FROM transactions
+                      WHERE ownable_id = ?
+                      ORDER BY dt DESC 
+                      LIMIT 1
+        ''', (ownable_id,))
+    return cursor.fetchone()[0]
+
+
 def execute_orders(ownable_id):
     connect()
     while True:
@@ -599,12 +610,12 @@ def execute_orders(ownable_id):
             break
 
         buy_ownership_id, _, buy_limit, _, buy_order_amount, buy_executed_amount, buy_expiry_dt, \
-            sell_ownership_id, _, sell_limit, _, sell_order_amount, sell_executed_amount, sell_expiry_dt, \
-            buyer_id, seller_id, buy_order_id, sell_order_id \
+        sell_ownership_id, _, sell_limit, _, sell_order_amount, sell_executed_amount, sell_expiry_dt, \
+        buyer_id, seller_id, buy_order_id, sell_order_id \
             = matching_orders
 
         if buy_limit is None and sell_limit is None:
-            raise AssertionError()  # TODO use last transaction price
+            price = current_value(ownable_id)
         elif buy_limit is None:
             price = sell_limit
         elif sell_limit is None:
@@ -941,4 +952,4 @@ def delete_ownable(ownable_id):
     cursor.execute('''
         DELETE FROM ownables
         WHERE rowid = ?
-        ''', (ownable_id,))
+        ''', (ownable_id,))