1 files changed, 50 insertions, 1 deletions

diff --git a/source/util/Diag.mc b/source/util/Diag.mc
index aea2a70..a09d3f8 100644
--- a/source/util/Diag.mc
+++ b/source/util/Diag.mc
@@ -1,5 +1,5 @@
 // Author:  cirakg & claude ai
-// Summary: Debug-only diagnostics (start-up time, memory) for `make perf` and `make memtest`.
+// Summary: Debug-only diagnostics: start-up time, memory, screen markers for UI scripts, and the performance overlay.
 //
 // Debug builds print one machine-readable line per event to the simulator
 // console: "DIAG", the event name, then key=value pairs, for example
@@ -10,13 +10,21 @@
 // (:release) versions instead, so a real watch running a release build never
 // logs anything.
 //
+// UI scripts (docker/scripts/screenshots.sh) wait for "DIAG shown <screen>"
+// lines before taking a screenshot, and read the PIN keypad's key positions
+// from "DIAG pin_keys" to tap them.
+//
 // Security rule: only timings and memory counters ever go through here, never
 // secrets, codes or entry names. This is the only file allowed to call
 // System.println outside tests (enforced by tools/lint_project.py).
 
+import Toybox.Graphics;
 import Toybox.Lang;
 import Toybox.System;
 
+// (:glance): the app object calls markStart() before the non-glance code is
+// loaded (apps with a glance load the rest only for the full app).
+(:glance)
 module Diag {
 
     // System.getTimer() value when the app object was created.
@@ -47,4 +55,45 @@ module Diag {
     (:release)
     function firstFrame() as Void {
     }
+
+    // A screen finished its first draw since it was shown.
+    (:debug)
+    function shown(screen as String) as Void {
+        System.println("DIAG shown " + screen);
+    }
+
+    (:release)
+    function shown(screen as String) as Void {
+    }
+
+    // Free-form key=value data for UI scripts (never secrets).
+    (:debug)
+    function data(event as String, values as String) as Void {
+        System.println("DIAG " + event + " " + values);
+    }
+
+    (:release)
+    function data(event as String, values as String) as Void {
+    }
+
+    // The performance overlay (toggled in the debug menu): draw time of the
+    // frame that started at startMs, and memory use.
+    (:debug)
+    var overlayOn as Boolean = false;
+
+    (:debug)
+    function overlay(dc as Graphics.Dc, frameStartMs as Number) as Void {
+        if (!overlayOn) {
+            return;
+        }
+        var stats = System.getSystemStats();
+        var text = (System.getTimer() - frameStartMs) + " ms  " + (stats.usedMemory * 100 / stats.totalMemory) + "% mem";
+        dc.setColor(Graphics.COLOR_YELLOW, Graphics.COLOR_BLACK);
+        dc.drawText(dc.getWidth() / 2, dc.getHeight() - dc.getFontHeight(Graphics.FONT_XTINY) - 2, Graphics.FONT_XTINY,
+            text, Graphics.TEXT_JUSTIFY_CENTER);
+    }
+
+    (:release)
+    function overlay(dc as Graphics.Dc, frameStartMs as Number) as Void {
+    }
 }