led2/.planning/phases/05-live-show-execution/05-02-SUMMARY.md

phase, plan, subsystem, tags, requires, provides, affects, tech-stack, key-files, key-decisions, patterns-established, requirements-completed, duration, completed

phase	plan	subsystem	tags	requires	provides	affects	tech-stack	key-files	key-decisions	patterns-established	requirements-completed	duration	completed
05-live-show-execution	02	ui	websocket preview show-selector vanilla-js css	phase provides 05-01 Cue scheduler backend that broadcasts preview_update WebSocket messages	Live preview panel DOM elements populated dynamically per device Show selector dropdown with LOAD button in transport bar preview_update WebSocket handler that updates device strip color and animation label buildPreviewStrips() — populates #live-preview from device list on init refreshShows() — fetches /api/shows and populates show-select dropdown Seek handler clears preview strips on user seek	05-03 keyboard-shortcuts show-management	added patterns Device strip pattern: data-driven RGB color swatch per device, updated via WebSocket messages Show load sequence: fetch show → populate tracks → setCurrentShowId → send WebSocket load msg → show preview panel Seek clear pattern: remove .active class + reset strip-color/strip-anim on seek	created modified lightsync/frontend/index.html lightsync/frontend/style.css lightsync/frontend/app.js	Preview panel starts hidden (display:none), made visible on show load — avoids empty panel before any show is loaded buildPreviewStrips called inside device fetch callback — strips built from same device list as timeline tracks Strip color uses raw RGB from cue params, not CSS variables — data-driven, not design token	Device strip structure: .strip-label (device name) + .strip-color (40x10px swatch) + .strip-anim (animation name) Active strip toggle: add/remove .active class on .device-strip, CSS handles color transitions	UI-04 SHW-03	20min	2026-04-07

Phase 05 Plan 02: Live Preview Panel and Show Selector Summary

Live preview panel with per-device RGB strips wired to preview_update WebSocket messages, plus show selector dropdown that loads shows into timeline and server

Performance

• Duration: ~20 min
• Started: 2026-04-07T10:00:00Z
• Completed: 2026-04-07T10:15:38Z
• Tasks: 2
• Files modified: 3

Accomplishments

• Added #live-preview panel div between timeline canvas and block inspector, starts hidden and becomes visible on show load
• Added show selector (#show-select dropdown + #btn-load-show) to transport bar using existing transport-file-select + transport-btn pattern
• Added keyboard hint label to far right of transport bar
• Appended complete terminal-aesthetic CSS for .live-preview, .device-strip, .strip-label, .strip-color, .strip-anim, .keyboard-hint
• Wired preview_update WebSocket message handler that calls updatePreviewStrip() to update per-device color swatch and animation label
• Added buildPreviewStrips() called from device fetch callback in initTimeline — creates one .device-strip[data-device-id] per device
• Added refreshShows() that fetches /api/shows and populates the show-select dropdown on load
• Added btn-load-show click handler: fetches show, populates timeline tracks from saved cues, sets current show ID, sends WebSocket load message, shows preview panel
• Added seek handler that clears all preview strips when user seeks (strips re-activate when next cue fires)

Task Commits

1. Task 1: Add preview panel HTML and show selector to index.html, add CSS styles - e0e412f (feat)
2. Task 2: Wire preview_update handler, show selector logic, and preview strip builder in app.js - e064954 (feat)

Files Created/Modified

• lightsync/frontend/index.html — Added #live-preview div, show-select dropdown, btn-load-show, keyboard-hint span
• lightsync/frontend/style.css — Appended .live-preview, .device-strip, .strip-label, .strip-color, .strip-anim, .keyboard-hint styles
• lightsync/frontend/app.js — Added setCurrentShowId import, preview_update handler, updatePreviewStrip(), buildPreviewStrips(), refreshShows(), show load handler, seek strip clear

Decisions Made

• Preview panel starts hidden (display:none), revealed to display:flex when a show loads — avoids empty panel state before first show load
• Strip color swatch uses rgb(r,g,b) directly from cue params, not CSS variables — data-driven per UI-SPEC Color section
• buildPreviewStrips() placed before initTimeline() in source order so it's available when the device fetch callback fires

Deviations from Plan

Minor Verification Discrepancy

1. [Rule 1 - Minor] preview_update count is 1, not 2 as plan's grep check expected

• Found during: Plan verification step
• Issue: Plan verification said grep -c 'preview_update' app.js should return "at least 2". The implementation has exactly 1 occurrence — the message type check msg.type === 'preview_update' which dispatches to updatePreviewStrip()
• Fix: No fix needed — the implementation is functionally correct per acceptance criteria. The verification comment "at least 2" may have assumed a comment/docstring that isn't required
• Impact: None — all acceptance criteria are fully satisfied; the handler is wired and functional

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Total deviations: 0 functional / 1 verification comment discrepancy (no fix needed) Impact on plan: None — plan executed correctly. All acceptance criteria met.

Issues Encountered

• Python not available as python or python3 on the system path — found Python at .venv/bin/python in the led2 project directory. Used that for verification scripts.

Known Stubs

None — all data is wired from real API calls (/api/shows, /api/devices) and live WebSocket messages (preview_update).

Next Phase Readiness

• Live preview panel is fully wired and ready for keyboard shortcut implementation (Plan 05-03)
• Show selector provides the foundation for the complete show load → schedule → play flow
• Preview strips will auto-update during playback once audio ticks drive the cue scheduler (05-01)

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Phase: 05-live-show-execution Completed: 2026-04-07