Show correct account label on loaded order lines

Quite a simple fix, we just assign the account-specific
`PositionTracker` to the level line's `._on_level_change()` handler
instead of whatever the current `OrderMode.current_pp` is set to.

Further this adds proper pane switching support such that when a user
modifies an order line from an account which is not the currently
selected one, the settings pane is changed to reflect the
account and thus corresponding position info for that account and
instrument B)

piker/ui/order_mode.py

@@ -79,38 +79,6 @@ class Dialog(Struct):
     fills: Dict[str, Any] = {}
 
 
-def on_level_change_update_next_order_info(
-
-    level: float,
-
-    # these are all ``partial``-ed in at callback assignment time.
-    line: LevelLine,
-    order: Order,
-    tracker: PositionTracker,
-
-) -> None:
-    '''
-    A callback applied for each level change to the line
-    which will recompute the order size based on allocator
-    settings. this is assigned inside
-    ``OrderMode.line_from_order()``
-
-    '''
-    # NOTE: the ``Order.account`` is set at order stage time
-    # inside ``OrderMode.line_from_order()``.
-    order_info = tracker.alloc.next_order_info(
-        startup_pp=tracker.startup_pp,
-        live_pp=tracker.live_pp,
-        price=level,
-        action=order.action,
-    )
-    line.update_labels(order_info)
-
-    # update bound-in staged order
-    order.price = level
-    order.size = order_info['size']
-
-
 @dataclass
 class OrderMode:
     '''
@@ -155,6 +123,42 @@ class OrderMode:
     }
     _staged_order: Optional[Order] = None
 
+    def on_level_change_update_next_order_info(
+        self,
+        level: float,
+
+        # these are all ``partial``-ed in at callback assignment time.
+        line: LevelLine,
+        order: Order,
+        tracker: PositionTracker,
+
+    ) -> None:
+        '''
+        A callback applied for each level change to the line
+        which will recompute the order size based on allocator
+        settings. this is assigned inside
+        ``OrderMode.line_from_order()``
+
+        '''
+        # NOTE: the ``Order.account`` is set at order stage time inside
+        # ``OrderMode.line_from_order()`` or is inside ``Order`` msg
+        # field for loaded orders.
+        order_info = tracker.alloc.next_order_info(
+            startup_pp=tracker.startup_pp,
+            live_pp=tracker.live_pp,
+            price=level,
+            action=order.action,
+        )
+        line.update_labels(order_info)
+
+        # update bound-in staged order
+        order.price = level
+        order.size = order_info['size']
+
+        # when an order is changed we flip the settings side-pane to
+        # reflect the corresponding account and pos info.
+        self.pane.on_ui_settings_change('account', order.account)
+
     def line_from_order(
         self,
         order: Order,
@@ -186,10 +190,12 @@ class OrderMode:
         # immediately
         if order.action != 'alert':
             line._on_level_change = partial(
-                on_level_change_update_next_order_info,
+                self.on_level_change_update_next_order_info,
                 line=line,
                 order=order,
-                tracker=self.current_pp,
+                # use the corresponding position tracker for the
+                # order's account.
+                tracker=self.trackers[order.account],
             )
 
         else:
@@ -238,7 +244,6 @@ class OrderMode:
 
         line = self.line_from_order(
             order,
-
             show_markers=True,
             # just for the stage line to avoid
             # flickering while moving the cursor
@@ -250,7 +255,6 @@ class OrderMode:
             # prevent flickering of marker while moving/tracking cursor
             only_show_markers_on_hover=False,
         )
-
         line = self.lines.stage_line(line)
 
         # hide crosshair y-line and label
@@ -274,10 +278,8 @@ class OrderMode:
         '''
         if not order:
             staged = self._staged_order
+            # apply order fields for ems
             oid = str(uuid.uuid4())
-            # symbol: Symbol = staged.symbol
-
-            # format order data for ems
             order = staged.copy()
             order.oid = oid
 
@@ -528,10 +530,9 @@ class OrderMode:
         msg: Status,
 
     ) -> Dialog:
-
         # NOTE: the `.order` attr **must** be set with the
         # equivalent order msg in order to be loaded.
-        order = Order(**msg.req)
+        order = msg.req
         oid = str(msg.oid)
         symbol = order.symbol
 
@@ -900,7 +901,6 @@ async def process_trade_msg(
                 mode.on_submit(oid)
 
             else:
-                # await tractor.breakpoint()
                 log.warning(
                     f'received msg for untracked dialog:\n{fmsg}'
                 )
@@ -922,6 +922,7 @@ async def process_trade_msg(
                         )
                     )
                 ):
+                    msg.req = order
                     dialog = mode.load_unknown_dialog_from_msg(msg)
                     mode.on_submit(oid)
                     # return dialog, msg