core: add input binding to control terminal inspector

src/Surface.zig

@@ -2278,6 +2278,12 @@ pub fn performBindingAction(self: *Surface, action: input.Binding.Action) !bool
             } else log.warn("runtime doesn't implement toggleFullscreen", .{});
         },
 
+        .inspector => |mode| {
+            if (@hasDecl(apprt.Surface, "controlInspector")) {
+                self.rt_surface.controlInspector(mode);
+            } else log.warn("runtime doesn't implement controlInspector", .{});
+        },
+
         .close_surface => self.close(),
 
         .close_window => try self.app.closeSurface(self),

src/apprt/embedded.zig

@@ -73,6 +73,9 @@ pub const App = struct {
         /// New window with options.
         new_window: ?*const fn (SurfaceUD, apprt.Surface.Options) callconv(.C) void = null,
 
+        /// Control the inspector visibility
+        control_inspector: ?*const fn (SurfaceUD, input.InspectorMode) callconv(.C) void = null,
+
         /// Close the current surface given by this function.
         close_surface: ?*const fn (SurfaceUD, bool) callconv(.C) void = null,
 
@@ -326,6 +329,15 @@ pub const Surface = struct {
         }
     }
 
+    pub fn controlInspector(self: *const Surface, mode: input.InspectorMode) void {
+        const func = self.app.opts.control_inspector orelse {
+            log.info("runtime embedder does not support the terminal inspector", .{});
+            return;
+        };
+
+        func(self.opts.userdata, mode);
+    }
+
     pub fn newSplit(self: *const Surface, direction: input.SplitDirection) !void {
         const func = self.app.opts.new_split orelse {
             log.info("runtime embedder does not support splits", .{});

src/input.zig

@@ -8,6 +8,7 @@ pub const keycodes = @import("input/keycodes.zig");
 pub const kitty = @import("input/kitty.zig");
 pub const Binding = @import("input/Binding.zig");
 pub const KeyEncoder = @import("input/KeyEncoder.zig");
+pub const InspectorMode = Binding.Action.InspectorMode;
 pub const SplitDirection = Binding.Action.SplitDirection;
 pub const SplitFocusDirection = Binding.Action.SplitFocusDirection;
 

src/input/Binding.zig

@@ -176,6 +176,10 @@ pub const Action = union(enum) {
     /// zoom/unzoom the current split.
     toggle_split_zoom: void,
 
+    /// Show, hide, or toggle the terminal inspector for the currently
+    /// focused terminal.
+    inspector: InspectorMode,
+
     /// Reload the configuration. The exact meaning depends on the app runtime
     /// in use but this usually involves re-reading the configuration file
     /// and applying any changes. Note that not all changes can be applied at
@@ -220,6 +224,13 @@ pub const Action = union(enum) {
         right,
     };
 
+    // Extern because it is used in the embedded runtime ABI.
+    pub const InspectorMode = enum(c_int) {
+        toggle,
+        show,
+        hide,
+    };
+
     /// Parse an action in the format of "key=value" where key is the
     /// action name and value is the action parameter. The parameter
     /// is optional depending on the action.