cold_display_guard/task_plan.md

Cold Display Guard Task Plan

Goal

Create an independent git project under ~/Code for monitoring food batches in a refrigerated display cabinet. The system tracks each configured display zone, starts a batch timer when food appears, ends it when the zone clears, and raises compliance alerts for over-3-hour removal without trash disposal or for over-3-hour food being put back.

Confirmed Decisions

• The trash bin is visible in the same camera frame.
• The display cabinet starts as a 4-column by 2-row layout, but zones must be configurable.
• A zone may contain multiple food items.
• Items in the same zone are treated as one batch.
• Mixed batches are not allowed; a zone must clear before a new batch can start.
• The first implementation is a standalone project, not a modification of store_dwell_alert.

Phases

Phase	Status	Notes
Create project skeleton	complete	Built under ~/Code/cold_display_guard.
Write design and implementation plan	complete	Saved in docs/plans/.
Implement core state engine	complete	Pure Python, no camera dependency.
Add config, CLI, README	complete	TOML config and JSONL event CLI skeleton.
Add tests	complete	python3 -m unittest discover -s tests -v passes.
Initialize git and commit	complete	Independent repository created.

Errors Encountered

Error	Attempt	Resolution
Ended batches reported 0 dwell seconds	First unittest run	Calculate dwell seconds before assigning ended_at.