fix(mobile): Only update position state after order submitted

Extract the logic checking whether the order is matching the currently open position
(we fail early if it's exact opposite direction and exact quantity).

Position state is only updated if the order got submitted.

mobile/native/src/trade/order/handler.rs

@@ -7,6 +7,7 @@ use crate::trade::order::FailureReason;
 use crate::trade::order::Order;
 use crate::trade::order::OrderState;
 use crate::trade::position;
+use crate::trade::position::handler::update_position_after_order_submitted;
 use anyhow::bail;
 use anyhow::Context;
 use anyhow::Result;
@@ -17,7 +18,7 @@ pub async fn submit_order(order: Order) -> Result<()> {
     let url = format!("http://{}", config::get_http_endpoint());
     let orderbook_client = OrderbookClient::new(Url::parse(&url)?);
 
-    if let Err(e) = position::handler::update_position_after_order_submitted(order) {
+    if let Err(e) = position::handler::get_position_matching_order(&order) {
         order_failed(Some(order.id), FailureReason::OrderNotAcceptable, e)?;
         bail!("Could not submit order because extending/reducing the position is not part of the MVP scope");
     }
@@ -35,6 +36,7 @@ pub async fn submit_order(order: Order) -> Result<()> {
     }
 
     update_order_state_in_db_and_ui(order.id, OrderState::Open)?;
+    update_position_after_order_submitted(&order)?;
 
     Ok(())
 }

mobile/native/src/trade/position/handler.rs

@@ -66,24 +66,28 @@ pub fn get_positions() -> Result<Vec<Position>> {
 ///
 /// If the new order submitted is an order that closes the current position, then the position will
 /// be updated to `Closing` state.
-pub fn update_position_after_order_submitted(submitted_order: Order) -> Result<()> {
-    if let Some(position) = db::get_positions()?.first() {
-        // closing the position
-        if position.direction == submitted_order.direction.opposite()
-            && position.quantity == submitted_order.quantity
-        {
-            db::update_position_state(position.contract_symbol, PositionState::Closing)?;
-            let mut position = position.clone();
-            position.position_state = PositionState::Closing;
-            event::publish(&EventInternal::PositionUpdateNotification(position));
-        } else {
-            bail!("Currently not possible to extend or reduce a position, you can only close the position with a counter-order");
-        }
+pub fn update_position_after_order_submitted(submitted_order: &Order) -> Result<()> {
+    if let Some(position) = get_position_matching_order(submitted_order) {
+        db::update_position_state(position.contract_symbol, PositionState::Closing)?;
+        let mut position = position.clone();
+        position.position_state = PositionState::Closing;
+        event::publish(&EventInternal::PositionUpdateNotification(position));
     }
-
     Ok(())
 }
 
+/// Returns the position that would be closed by submitted, if there is any
+pub fn get_position_matching_order(order: &Order) -> Result<Option<Position>> {
+    Ok(if let Some(position) = db::get_positions()?.first() {
+        // closing the position
+        ensure!(position.direction == order.direction.opposite()
+                && position.quantity == order.quantity, "Currently not possible to extend or reduce a position, you can only close the position with a counter-order");
+        Some(position.clone())
+    } else {
+        None
+    })
+}
+
 /// Resets the position to open again
 ///
 /// This should be called if a went in a dirty state, e.g. the position is currently in