# Clock UI: Symmetry, Auto-Update, and System-Wide Header Clock

**Date**: 2026-02-17

## Task Description

Three improvements to clock display:
1. Make clock positioning symmetric with battery icon in headers
2. Auto-update the clock without requiring a button press
3. Show the clock everywhere the battery appears in system UI headers

## Changes Made

### 1. Moved clock rendering into `drawHeader` (BaseTheme + LyraTheme)

Previously the clock was drawn only in `HomeActivity::render()` with ad-hoc positioning (`contentSidePadding`, `topPadding`). Now it's rendered inside `drawHeader()` in both theme implementations, using the same positioning pattern as the battery:

- **Battery** (right): icon at `rect.x + rect.width - 12 - batteryWidth`, text at `rect.y + 5`
- **Clock** (left): text at `rect.x + 12`, `rect.y + 5`

Both use `SMALL_FONT_ID`, so the font matches. The 12px margin from the edge is now symmetric on both sides.

**Files changed:**
- `src/components/themes/BaseTheme.cpp` -- added clock block in `drawHeader()`, added `#include <ctime>` and `#include "CrossPointSettings.h"`
- `src/components/themes/lyra/LyraTheme.cpp` -- same changes for Lyra theme's `drawHeader()`

### 2. Clock now appears on all header screens automatically

Since `drawHeader()` is called by: HomeActivity, MyLibraryActivity, RecentBooksActivity, SettingsActivity, LookedUpWordsActivity, DictionarySuggestionsActivity -- the clock now appears on all of these screens when enabled. No per-activity code needed.

### 3. Removed standalone clock code from HomeActivity

- `src/activities/home/HomeActivity.cpp` -- removed the 15-line clock rendering block that was separate from `drawHeader()`

### 4. Added auto-update (once per minute) on home screen

- `src/activities/home/HomeActivity.h` -- added `lastRenderedMinute` field to track the currently displayed minute
- `src/activities/home/HomeActivity.cpp` -- added minute-change detection in `loop()` that calls `requestUpdate()` when the minute rolls over, triggering a screen refresh

## Build Verification

- `pio run -e mod` -- SUCCESS (RAM: 31.0%, Flash: 78.8%)

## Follow-up Items

- The auto-update only applies to HomeActivity. Other screens (Settings, Library, etc.) will show the current time when they render but won't auto-refresh purely for clock updates, which is appropriate for e-ink.
- The DictionarySuggestionsActivity and LookedUpWordsActivity pass a non-zero `contentX` offset in their header rect, so the clock position adjusts correctly via `rect.x + 12`.