1 files changed, 120 insertions, 8 deletions

diff --git a/source/ui/GlanceView.mc b/source/ui/GlanceView.mc
index a7207ce..4540f2a 100644
--- a/source/ui/GlanceView.mc
+++ b/source/ui/GlanceView.mc
@@ -1,23 +1,83 @@
 // Author:  cirakg & claude ai
-// Summary: The glance (widget-list preview): app name and number of entries.
+// Summary: The glance (widget-list preview): the app name and number of entries, or the opt-in favourite code with its countdown.
 //
-// Glances run with very little memory, so this reads only the entry index
-// from storage and opens no vault and no keys. The opt-in favourite code
-// (README 13.1) comes with M8.
+// Glances run with very little memory (64 KB), so this opens no vault: it
+// reads the entry index, and with "Show the favourite code in the glance"
+// on, the one entry the app sealed for it (GlanceCode). The code is
+// computed once per period (one HMAC; SHA-512 once per period too) and
+// redrawn every second for the countdown bar while the glance is visible.
+// The secret is wiped when the glance is hidden.
 
 import Toybox.Application;
 import Toybox.Graphics;
 import Toybox.Lang;
+import Toybox.Math;
+import Toybox.System;
+import Toybox.Timer;
 import Toybox.WatchUi;
 
 (:glance)
 class OtpGlanceView extends WatchUi.GlanceView {
 
+    private var _item as GlanceCode.Item? = null;
+    private var _timer as Timer.Timer? = null;
+    private var _counter as Long = -1l;
+    private var _code as String = "";
+    private var _measured as Boolean = false;
+
     function initialize() {
         GlanceView.initialize();
     }
 
+    function onShow() as Void {
+        var item = GlanceCode.load();
+        _item = item;
+        _counter = -1l;
+        if (item != null) {
+            try {
+                var timer = new Timer.Timer();
+                timer.start(method(:onTick), 1000, true);
+                _timer = timer;
+            } catch (e instanceof Lang.Exception) {
+                // No timers here: the code still updates whenever the system redraws.
+            }
+        }
+    }
+
+    function onHide() as Void {
+        var timer = _timer;
+        if (timer != null) {
+            timer.stop();
+        }
+        _timer = null;
+        var item = _item;
+        if (item != null) {
+            item.wipe();
+        }
+        _item = null;
+        _code = "";
+    }
+
+    function onTick() as Void {
+        WatchUi.requestUpdate();
+    }
+
     function onUpdate(dc as Graphics.Dc) as Void {
+        var item = _item;
+        if (item != null) {
+            drawCode(dc, item);
+        } else {
+            drawCount(dc);
+        }
+        // The simulator starts in the glance; launch scripts open the app from it.
+        if (!_measured) {
+            _measured = true;
+            Diag.glanceMemory();
+        }
+        Diag.shown(item != null ? "glance_code" : "glance");
+    }
+
+    private function drawCount(dc as Graphics.Dc) as Void {
         var count = 0;
         var meta = Application.Storage.getValue("m");
         if (meta instanceof Dictionary) {
@@ -27,11 +87,63 @@ class OtpGlanceView extends WatchUi.GlanceView {
             }
         }
         var h = dc.getHeight();
+        var top = h / 2 - dc.getFontHeight(Graphics.FONT_GLANCE);
+        var x = inset(dc, top);
         dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_TRANSPARENT);
-        dc.drawText(0, h / 2 - dc.getFontHeight(Graphics.FONT_GLANCE), Graphics.FONT_GLANCE, "OTP WALLET", Graphics.TEXT_JUSTIFY_LEFT);
+        dc.drawText(x, top, Graphics.FONT_GLANCE, "OTP WALLET", Graphics.TEXT_JUSTIFY_LEFT);
         dc.setColor(Graphics.COLOR_LT_GRAY, Graphics.COLOR_TRANSPARENT);
-        dc.drawText(0, h / 2, Graphics.FONT_GLANCE, count == 1 ? "1 entry" : count + " entries", Graphics.TEXT_JUSTIFY_LEFT);
-        // The simulator starts in the glance; launch scripts open the app from it.
-        Diag.shown("glance");
+        dc.drawText(x, h / 2, Graphics.FONT_GLANCE, count == 1 ? "1 entry" : count + " entries",
+            Graphics.TEXT_JUSTIFY_LEFT);
+    }
+
+    // How far right to start text whose top is at y, so a round screen's
+    // edge doesn't cut it. A glance doesn't know where it sits, so this
+    // assumes it is centred across the screen and starts at the top, which
+    // overestimates the cut (the Instinct 3's glance reaches into the
+    // screen's top-left curve; on most round watches this is 0 or a few
+    // pixels).
+    private function inset(dc as Graphics.Dc, y as Number) as Number {
+        var screen = System.getDeviceSettings();
+        if (screen.screenShape != System.SCREEN_SHAPE_ROUND) {
+            return 0;
+        }
+        var r = screen.screenWidth / 2;
+        var dy = r - y;
+        var edge = r - Math.sqrt(r * r - dy * dy).toNumber();
+        var left = (screen.screenWidth - dc.getWidth()) / 2;
+        return edge > left ? edge - left : 0;
+    }
+
+    // The label, the code and a bar for the seconds left in the period.
+    private function drawCode(dc as Graphics.Dc, item as GlanceCode.Item) as Void {
+        var now = Clock.nowUnix(0);
+        var counter = item.counter(now);
+        if (counter != _counter) {
+            _code = GlanceCode.grouped(item.code(now));
+            _counter = counter;
+        }
+        var w = dc.getWidth();
+        var h = dc.getHeight();
+        // The label ends at mid-height, like the entry count's first line:
+        // on some watches (Instinct 3) the glance's top corners are cut by
+        // the round screen, and a glance can't know where it sits.
+        var labelH = dc.getFontHeight(Graphics.FONT_GLANCE);
+        var codeFont = Graphics.FONT_GLANCE_NUMBER;
+        if (h / 2 + dc.getFontHeight(codeFont) + 5 > h) {
+            codeFont = Graphics.FONT_GLANCE;
+        }
+        var codeH = dc.getFontHeight(codeFont);
+        var top = h / 2 - labelH;
+        dc.setColor(Graphics.COLOR_LT_GRAY, Graphics.COLOR_TRANSPARENT);
+        // One inset for the block (the top line's), so the lines align.
+        var barX = inset(dc, top);
+        dc.drawText(barX, top, Graphics.FONT_GLANCE, item.label.toUpper(), Graphics.TEXT_JUSTIFY_LEFT);
+        dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_TRANSPARENT);
+        dc.drawText(barX, h / 2, codeFont, _code, Graphics.TEXT_JUSTIFY_LEFT);
+        var barY = h / 2 + codeH + 2;
+        dc.setColor(Graphics.COLOR_DK_GRAY, Graphics.COLOR_TRANSPARENT);
+        dc.fillRectangle(barX, barY, w - barX, 3);
+        dc.setColor(Graphics.COLOR_BLUE, Graphics.COLOR_TRANSPARENT);
+        dc.fillRectangle(barX, barY, (w - barX) * item.secondsLeft(now) / item.periodSeconds(), 3);
     }
 }