---
phase: 06-keyboard-ux-filter-pickers
plan: "01"
subsystem: ui
tags: [textual, modalscreen, listview, filter, picker]

# Dependency graph
requires:
  - phase: 05-data-surface-stats-bar-detail-panel
    provides: MainScreen with StatsBar and DetailPanel wired; push_screen pattern for overlay screens
provides:
  - FilterPickerScreen(ModalScreen) reusable VIM-style picker modal for Room/Container/Category filters
affects: [06-02, 06-03, 06-04]

# Tech tracking
tech-stack:
  added: []
  patterns:
    - ModalScreen subclass with dismiss(result) for returning selected value to caller
    - In-memory list filtering with active-item float-to-top pattern
    - j/k programmatic ListView navigation while Input holds focus

key-files:
  created:
    - possession/tui/screens/filter_picker.py
  modified: []

key-decisions:
  - "FilterPickerScreen is fully data-agnostic — receives items as a parameter, never imports possession models"
  - "Focus always stays on Input (type-ahead); j/k call lv.action_cursor_down/up programmatically to avoid key-in-search pitfall"
  - "Active filter item floats to top with checkmark marker via in-memory sort before list rebuild"
  - "Empty-state rows (no items / no matches) are not added to self._filtered so Enter on them is a no-op"

patterns-established:
  - "ModalScreen + dismiss(result) + push_screen(screen, callback) — caller/picker contract for all picker screens in this phase"
  - "_rebuild_list(query) pattern: clear ListView, float active, filter, re-populate — called on mount and on every Input.Changed"

requirements-completed: [FILT-01, FILT-02, FILT-03]

# Metrics
duration: 1min
completed: 2026-02-28
---

# Phase 6 Plan 01: FilterPickerScreen Modal Summary

**Single reusable `FilterPickerScreen(ModalScreen)` with type-ahead filtering, VIM navigation, and active-filter toggle that serves all three picker types (Room, Container, Category)**

## Performance

- **Duration:** ~1 min
- **Started:** 2026-02-28T10:17:40Z
- **Completed:** 2026-02-28T10:18:35Z
- **Tasks:** 1
- **Files modified:** 1

## Accomplishments
- Created `FilterPickerScreen(ModalScreen)` covering all plan requirements in a single file
- Type-ahead Input filters list live while j/k navigate and Enter/Escape confirm/cancel
- Active filter floats to top with "✓" marker; highlighted active item shows "Enter to clear filter" hint
- Empty-state handling for both empty items list and no-matches-after-filter cases

## Task Commits

Each task was committed atomically:

1. **Task 1: Create FilterPickerScreen modal** - `e6d2c19` (feat)

**Plan metadata:** (docs commit follows)

## Files Created/Modified
- `possession/tui/screens/filter_picker.py` - FilterPickerScreen(ModalScreen) with compose, on_mount, _rebuild_list, on_input_changed, on_key, on_list_view_highlighted

## Decisions Made
- FilterPickerScreen receives items list as a parameter (data-agnostic) — never imports possession models; this keeps the picker reusable and avoids circular imports
- Focus stays on Input always; j/k programmatically call lv.action_cursor_down/up — avoids the key-in-search pitfall documented in RESEARCH.md
- Empty-state ListItems are not added to self._filtered so Enter on them does nothing (correct behavior for disabled rows)
- Python 3.9 compatible throughout: Optional[int], List[Dict] — no union syntax

## Deviations from Plan

None — plan executed exactly as written.

## Issues Encountered

None.

## User Setup Required

None — no external service configuration required.

## Next Phase Readiness
- `FilterPickerScreen` is importable and fully functional
- Plan 02 can wire `r`/`c`/`t` bindings in MainScreen and call `app.push_screen(FilterPickerScreen(...), callback)` immediately
- Filter state pattern (Optional[int] fields + name cache) documented in RESEARCH.md ready for implementation

---
*Phase: 06-keyboard-ux-filter-pickers*
*Completed: 2026-02-28*
