Add first pane movement for MoveFocus/SwapPane. (#11044)

This commit adds the ability to target the first pane in the tree,
always.

I wasn't able to find an existing issue for this, it is just a personal
feature for me. I won't be heartbroken if it does not get merged.

As motivation, I frequently have setups where the thing I am primarily
working on is a large pane on the left and everything else is in smaller
panes positioned elsewhere. I like to have one hotkey where I can go to
any pane and then make it the "primary" pane if I am changing what I am
working on or need to focus on another set of code/documentation/etc.

## Validation Steps Performed
Confirmed that the move focus and swap pane variants both affect the
correct pane.

doc/cascadia/profiles.schema.json

@@ -299,7 +299,8 @@
         "down",
         "previous",
         "nextInOrder",
-        "previousInOrder"
+        "previousInOrder",
+        "first"
       ],
       "type": "string"
     },

src/cascadia/TerminalApp/AppCommandlineArgs.cpp

@@ -399,8 +399,10 @@ static const std::map<std::string, FocusDirection> focusDirectionMap = {
     { "right", FocusDirection::Right },
     { "up", FocusDirection::Up },
     { "down", FocusDirection::Down },
+    { "previous", FocusDirection::Previous },
     { "nextInOrder", FocusDirection::NextInOrder },
     { "previousInOrder", FocusDirection::PreviousInOrder },
+    { "first", FocusDirection::First },
 };
 
 // Method Description:

src/cascadia/TerminalApp/Pane.cpp

@@ -251,6 +251,27 @@ std::shared_ptr<Pane> Pane::NavigateDirection(const std::shared_ptr<Pane> source
         return PreviousPane(sourcePane);
     }
 
+    if (direction == FocusDirection::First)
+    {
+        std::shared_ptr<Pane> firstPane = nullptr;
+        WalkTree([&](auto p) {
+            if (p->_IsLeaf())
+            {
+                firstPane = p;
+                return true;
+            }
+
+            return false;
+        });
+
+        // Don't need to do any movement if we are the source and target pane.
+        if (firstPane == sourcePane)
+        {
+            return nullptr;
+        }
+        return firstPane;
+    }
+
     // We are left with directional traversal now
     // If the focus direction does not match the split direction, the source pane
     // and its neighbor must necessarily be contained within the same child.

src/cascadia/TerminalSettingsModel/ActionArgs.cpp

@@ -296,7 +296,10 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
             return RS_(L"MoveFocusNextInOrder");
         case FocusDirection::PreviousInOrder:
             return RS_(L"MoveFocusPreviousInOrder");
+        case FocusDirection::First:
+            return RS_(L"MoveFocusFirstPane");
         }
+
         return winrt::hstring{
             fmt::format(std::wstring_view(RS_(L"MoveFocusWithArgCommandKey")),
                         directionString)
@@ -326,7 +329,10 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
             return RS_(L"SwapPaneNextInOrder");
         case FocusDirection::PreviousInOrder:
             return RS_(L"SwapPanePreviousInOrder");
+        case FocusDirection::First:
+            return RS_(L"SwapPaneFirstPane");
         }
+
         return winrt::hstring{
             fmt::format(std::wstring_view(RS_(L"SwapPaneWithArgCommandKey")),
                         directionString)

src/cascadia/TerminalSettingsModel/ActionArgs.idl

@@ -35,7 +35,8 @@ namespace Microsoft.Terminal.Settings.Model
         Down,
         Previous,
         PreviousInOrder,
-        NextInOrder
+        NextInOrder,
+        First
     };
 
     enum SplitState

src/cascadia/TerminalSettingsModel/Resources/en-US/Resources.resw

@@ -246,6 +246,15 @@
   <data name="MoveFocusToLastUsedPane" xml:space="preserve">
     <value>Move focus to the last used pane</value>
   </data>
+  <data name="MoveFocusNextInOrder" xml:space="preserve">
+    <value>Move focus to the next pane in order</value>
+  </data>
+  <data name="MoveFocusPreviousInOrder" xml:space="preserve">
+    <value>Move focus to the previous pane in order</value>
+  </data>
+  <data name="MoveFocusFirstPane" xml:space="preserve">
+    <value>Move focus to the first pane</value>
+  </data>
   <data name="SwapPaneCommandKey" xml:space="preserve">
     <value>Swap pane</value>
   </data>
@@ -256,6 +265,15 @@
   <data name="SwapPaneToLastUsedPane" xml:space="preserve">
     <value>Swap panes with the last used pane</value>
   </data>
+  <data name="SwapPaneNextInOrder" xml:space="preserve">
+    <value>Swap panes with the next pane in order</value>
+  </data>
+  <data name="SwapPanePreviousInOrder" xml:space="preserve">
+    <value>Swap panes with the previous pane in order</value>
+  </data>
+  <data name="SwapPaneFirstPane" xml:space="preserve">
+    <value>Swap panes with the first pane</value>
+  </data>
   <data name="NewTabCommandKey" xml:space="preserve">
     <value>New tab</value>
   </data>
@@ -436,18 +454,6 @@
     <value>Windows Console Host</value>
     <comment>Name describing the usage of the classic windows console as the terminal UI. (`conhost.exe`)</comment>
   </data>
-  <data name="MoveFocusNextInOrder" xml:space="preserve">
-    <value>Move focus to the next pane in order</value>
-  </data>
-  <data name="MoveFocusPreviousInOrder" xml:space="preserve">
-    <value>Move focus to the previous pane in order</value>
-  </data>
-  <data name="SwapPaneNextInOrder" xml:space="preserve">
-    <value>Swap panes with the next pane in order</value>
-  </data>
-  <data name="SwapPanePreviousInOrder" xml:space="preserve">
-    <value>Swap panes with the previous pane in order</value>
-  </data>
   <data name="MinimizeToTrayCommandKey" xml:space="preserve">
     <value>Minimize current window to tray</value>
   </data>

src/cascadia/TerminalSettingsModel/TerminalSettingsSerializationHelpers.h

@@ -337,7 +337,7 @@ struct ::Microsoft::Terminal::Settings::Model::JsonUtils::ConversionTrait<::winr
 // Possible FocusDirection values
 JSON_ENUM_MAPPER(::winrt::Microsoft::Terminal::Settings::Model::FocusDirection)
 {
-    JSON_MAPPINGS(7) = {
+    JSON_MAPPINGS(8) = {
         pair_type{ "left", ValueType::Left },
         pair_type{ "right", ValueType::Right },
         pair_type{ "up", ValueType::Up },
@@ -345,6 +345,7 @@ JSON_ENUM_MAPPER(::winrt::Microsoft::Terminal::Settings::Model::FocusDirection)
         pair_type{ "previous", ValueType::Previous },
         pair_type{ "previousInOrder", ValueType::PreviousInOrder },
         pair_type{ "nextInOrder", ValueType::NextInOrder },
+        pair_type{ "first", ValueType::First },
     };
 };
 

src/cascadia/TerminalSettingsModel/defaults.json

@@ -348,6 +348,7 @@
         { "command": { "action": "moveFocus", "direction": "previous" }, "keys": "ctrl+alt+left"},
         { "command": { "action": "moveFocus", "direction": "previousInOrder" } },
         { "command": { "action": "moveFocus", "direction": "nextInOrder" } },
+        { "command": { "action": "moveFocus", "direction": "first" } },
         { "command": { "action": "swapPane", "direction": "down" } },
         { "command": { "action": "swapPane", "direction": "left" } },
         { "command": { "action": "swapPane", "direction": "right" } },
@@ -355,6 +356,7 @@
         { "command": { "action": "swapPane", "direction": "previous"} },
         { "command": { "action": "swapPane", "direction": "previousInOrder"} },
         { "command": { "action": "swapPane", "direction": "nextInOrder"} },
+        { "command": { "action": "swapPane", "direction": "first" } },
         { "command": "togglePaneZoom" },
         { "command": "toggleSplitOrientation" },
         { "command": "toggleReadOnlyMode" },