mikenrafter · Nov 7, 2026 · Nov 7, 2026 · Nov 7, 2026 · Nov 7, 2026 · Nov 7, 2026
diff --git a/lib/compute/vendor_sleep.dart b/lib/compute/vendor_sleep.dart
@@ -47,6 +47,27 @@ const String kOurRingNightSource = 'hr_5min_stager';
 /// ('auto_fallback'), not the device's.
 const String kHrWindowNightSource = 'hr_5min_window';
 
+/// The point list a night is drawn and read from: each epoch's stage from its
+/// start, closed by a final point at wake. A stretch no epoch covers gets an
+/// `unobserved` boundary where the epoch before it ends, so a reader of the
+/// list never carries that epoch's stage across the hole.
+List<Map<String, Object?>> vendorHypnogram(
+    List<VendorEpoch> epochs, int wakeSec) {
+  final out = <Map<String, Object?>>[];
+  for (var i = 0; i < epochs.length; i++) {
+    final e = epochs[i];
+    out.add({'t': e.startSec, 'stage': e.stage});
+    final next = i + 1 < epochs.length ? epochs[i + 1].startSec : wakeSec;
+    if (next > e.endSec) out.add({'t': e.endSec, 'stage': 'unobserved'});
+  }
+  final last = epochs.last;
+  out.add({
+    't': wakeSec,
+    'stage': last.endSec < wakeSec ? 'unobserved' : last.stage,
+  });
+  return out;
+}
+
 /// One night of one device's epochs, as `vendor_sleep_epoch` groups them.
 class VendorNight {
   final String deviceId;

diff --git a/lib/data/local_repository_impl.dart b/lib/data/local_repository_impl.dart
@@ -29,6 +29,7 @@ import '../compute/manual_session.dart';
 import '../compute/onehz_pipeline.dart' show kUnknownAbsenceNote, needInputNote;
 import '../compute/profile.dart';
 import '../compute/quiet_level.dart';
+import '../compute/vendor_sleep.dart' show vendorHypnogram;
 import 'package:openstrap_protocol/openstrap_protocol.dart' as proto;
 import 'package:openstrap_analytics/onehz.dart' as ana;
 
@@ -2316,10 +2317,7 @@ class LocalRepositoryImpl extends LocalRepository {
         'stage_min': minutes,
         // Same point shape as our own night: each stage from its start,
         // closed by a final point at wake.
-        'hypnogram': [
-          for (final e in n.epochs) {'t': e.startSec, 'stage': e.stage},
-          {'t': n.offsetSec, 'stage': n.epochs.last.stage},
-        ],
+        'hypnogram': vendorHypnogram(n.epochs, n.offsetSec),
       });
     }
     return out;

diff --git a/lib/l10n/app_de.arb b/lib/l10n/app_de.arb
@@ -1176,6 +1176,10 @@
   "metricDetailSlotNoValueRecording": "{day}, kein Wert · {who}",
   "metricDetailSlotNothingRecording": "{day}, keine Aufzeichnung",
   "metricDetailOpenDay": "{day} öffnen",
+  "chartPanelLatest": "ZULETZT",
+  "chartPanelSelected": "AUSGEWÄHLT",
+  "chartPanelSevenDayAvg": "7-Tage-Schnitt",
+  "chartPanelVsAvg": "ggü. Schnitt",
   "metricDetailNoRecordLabel": "Kein Eintrag",
   "metricDetailLowest": "Niedrigster",
   "metricDetailTypical": "Typisch",

diff --git a/lib/l10n/app_en.arb b/lib/l10n/app_en.arb
@@ -5668,6 +5668,22 @@
       }
     }
   },
+  "chartPanelLatest": "LATEST",
+  "@chartPanelLatest": {
+    "description": "Caption prefix on the panel under a chart when nothing is selected: the newest reading. Shown upper-case where the script has case. It is not a judgement such as best."
+  },
+  "chartPanelSelected": "SELECTED",
+  "@chartPanelSelected": {
+    "description": "Caption prefix on the panel under a chart while a finger is on the chart: the reading the finger is on."
+  },
+  "chartPanelSevenDayAvg": "7-day avg",
+  "@chartPanelSevenDayAvg": {
+    "description": "Metric-detail panel stat: the last 7 days up to today, the same figure whichever day is shown."
+  },
+  "chartPanelVsAvg": "vs avg",
+  "@chartPanelVsAvg": {
+    "description": "Metric-detail panel stat: the shown value minus that 7-day average."
+  },
   "metricDetailNoRecordLabel": "No record",
   "@metricDetailNoRecordLabel": {
     "description": "Value text shown in the touched-day row when that day has no record."

diff --git a/lib/l10n/app_es.arb b/lib/l10n/app_es.arb
@@ -1133,6 +1133,10 @@
   "metricDetailSlotNoRecord": "{day}, sin registro",
   "metricDetailSlotWithValue": "{day}, {value} {unit}",
   "metricDetailOpenDay": "Abrir {day}",
+  "chartPanelLatest": "ÚLTIMO",
+  "chartPanelSelected": "SELECCIONADO",
+  "chartPanelSevenDayAvg": "Media de 7 días",
+  "chartPanelVsAvg": "vs. media",
   "metricDetailNoRecordLabel": "Sin registro",
   "metricDetailLowest": "Mínimo",
   "metricDetailTypical": "Típico",

diff --git a/lib/l10n/app_fr.arb b/lib/l10n/app_fr.arb
@@ -1133,6 +1133,10 @@
   "metricDetailSlotNoRecord": "{day}, aucun enregistrement",
   "metricDetailSlotWithValue": "{day}, {value} {unit}",
   "metricDetailOpenDay": "Ouvrir {day}",
+  "chartPanelLatest": "DERNIER",
+  "chartPanelSelected": "SÉLECTIONNÉ",
+  "chartPanelSevenDayAvg": "Moy. sur 7 jours",
+  "chartPanelVsAvg": "vs moy.",
   "metricDetailNoRecordLabel": "Aucun enregistrement",
   "metricDetailLowest": "Minimum",
   "metricDetailTypical": "Typique",

diff --git a/lib/l10n/app_hi.arb b/lib/l10n/app_hi.arb
@@ -1133,6 +1133,10 @@
   "metricDetailSlotNoRecord": "{day}, कोई रिकॉर्ड नहीं",
   "metricDetailSlotWithValue": "{day}, {value} {unit}",
   "metricDetailOpenDay": "{day} खोलें",
+  "chartPanelLatest": "नवीनतम",
+  "chartPanelSelected": "चुना गया",
+  "chartPanelSevenDayAvg": "7 दिन का औसत",
+  "chartPanelVsAvg": "औसत से अंतर",
   "metricDetailNoRecordLabel": "कोई रिकॉर्ड नहीं",
   "metricDetailLowest": "न्यूनतम",
   "metricDetailTypical": "सामान्य",

diff --git a/lib/l10n/app_ru.arb b/lib/l10n/app_ru.arb
@@ -2507,6 +2507,10 @@
       }
     }
   },
+  "chartPanelLatest": "ПОСЛЕДНЕЕ",
+  "chartPanelSelected": "ВЫБРАНО",
+  "chartPanelSevenDayAvg": "Среднее за 7 дн.",
+  "chartPanelVsAvg": "от среднего",
   "metricDetailNoRecordLabel": "Нет записи",
   "metricDetailLowest": "Наименьшее",
   "metricDetailTypical": "Обычное",

diff --git a/lib/l10n/app_th.arb b/lib/l10n/app_th.arb
@@ -5668,6 +5668,10 @@
       }
     }
   },
+  "chartPanelLatest": "ล่าสุด",
+  "chartPanelSelected": "ที่เลือก",
+  "chartPanelSevenDayAvg": "ค่าเฉลี่ย 7 วัน",
+  "chartPanelVsAvg": "เทียบค่าเฉลี่ย",
   "metricDetailNoRecordLabel": "ไม่มีข้อมูลบันทึก",
   "@metricDetailNoRecordLabel": {
     "description": "Value text shown in the touched-day row when that day has no record."

diff --git a/lib/l10n/app_zh.arb b/lib/l10n/app_zh.arb
@@ -1133,6 +1133,10 @@
   "metricDetailSlotNoRecord": "{day}，无记录",
   "metricDetailSlotWithValue": "{day}，{value} {unit}",
   "metricDetailOpenDay": "打开{day}",
+  "chartPanelLatest": "最新",
+  "chartPanelSelected": "已选",
+  "chartPanelSevenDayAvg": "7 天平均",
+  "chartPanelVsAvg": "与平均相比",
   "metricDetailNoRecordLabel": "无记录",
   "metricDetailLowest": "最低",
   "metricDetailTypical": "典型",

diff --git a/lib/ui2/README.md b/lib/ui2/README.md
@@ -121,6 +121,53 @@ that did not exist.
 `Scrubber` is the only drag: it carries the slider role, so increase/decrease
 reach it without a pointer, and `describe` is what those steps say out loud.
 
+### ChartPanel — what a chart reads, always on screen
+
+```dart
+ChartPanel({required String? time, required bool scrubbed, required Color color,
+            required List<ChartPanelCell> cells, List<ChartPanelCell> stats = const [],
+            List<String> timeSpan = const [], VoidCallback? onOpen, String? openLabel})
+ChartPanelCell(String label, {Color? color, String? value, Color? valueColor})
+```
+
+Put it under a chart that has a `Scrubber`, in the same card. It is there at
+rest and while a finger is on the chart, so the chart never changes height under
+the thumb and nothing is readable only while it is held. There is no pop-in.
+
+- **Caption.** `LATEST · <time>` at rest (the newest reading, or on a night the
+  stage at wake), `SELECTED · <time>` while scrubbing. Neither is a judgement.
+  While scrubbing the caption and a 1.5 pt border take the series colour
+  (`p.on(...)`, so they clear 4.5:1 on `card2`); at rest there is no border.
+- **Box.** `card2` fill, `R.rMd`, no shadow, inset in the chart's card. Its rect
+  is the same at rest, scrubbing, on a gap and at any text size. The caption
+  reserves the height of the tallest of `timeSpan` (every time the panel can
+  show), measured once per span, width, scale and locale, so a day name that
+  wraps in one language cannot move the panel.
+- **Cells.** One per series, each its label and the value at that instant.
+  A series with nothing there reads `—`: never a neighbour's value, never an
+  interpolation. One cell is drawn large; several are equal width, one row when
+  they fit and wrapped when they do not.
+- **Stats.** Summary figures of the one series (`7-day avg`, `vs avg` on metric
+  detail), spoken as one `label value` node. A stat with no value is a dash and
+  is not spoken.
+- **Spoken once, by one owner at a time.** While a finger is on the chart the
+  `Scrubber` speaks the whole selected reading (`describe` carries every value
+  the panel shows, a missing one as "No record") and the panel's caption and
+  cells are excluded. At rest nothing is selected, so the panel speaks the
+  `LATEST · <day>, label value, …` reading itself, as one node, and the slider
+  says only "Nothing selected". `Scrubber.describe` and the panel must read the
+  same thing at every position. A screen with two panels for one instant (the
+  sleep night) speaks each chart's reading once, so each value is heard once per
+  chart.
+- **Open the day.** `onOpen` makes the whole panel an `Open <day>` button of at
+  least 48 dp. Pass it only for a day with a value: an action is a promise, and
+  an empty day has no screen behind it.
+
+The caller owns the reading. Metric detail, readiness and the two sleep charts
+each build the cells from the series the painter draws; the sleep charts read
+the stage from the night's timestamped boundaries (not the resample the painter
+draws) and a signal from its nearest sample within 15 minutes, else a dash.
+
 ### Layout primitives
 
 ```dart
@@ -373,7 +420,8 @@ Five rules:
    curve, and it does not take taps. **A mark without a `footnote` is a line
    nobody can read**: the footnote is the mark's only screen-reader form and
    the only thing that can say what it is. Keep the wording flat — a version
-   change is provenance, not something that happened to the user.
+   change is provenance, not something that happened to the user. Multi-day
+   charts (metric detail) use `xMarks`.
 4. **More than one colour means a `legend`.** Use the painters' own, never
    retyped: `Hypnogram.legend(p, l)`, `IntervalLadder.legend` (instance).
    The swatch is the mark's *solved* colour, so the key and the plot can never