031-flash-card/docs/milestones/mil-004-step3-flip-cards.md

MIL-004: Step 3 - Flip the cards

Metadata

Key	Value
ID	MIL-004
CrossReference	BC-001, US-001, UC-001
Language	en
Domain	it

Version History

Date	Status	Author	Reviewer	Change	Commit
2026-10-14	Accepted	Jens Tirsvad Nielsen	AI as stand-in for S01	Initial version	pending

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Purpose

Decide whether assignment step 3 works: three seconds after a card appears, it turns over and shows the Danish translation.

Deliverable

After 3000 ms the card shows card_back.png, the language name "Danish", the translation, and white text. A button press shows the front of a new card with black text and restarts the timer; a press before the 3000 ms have passed cancels the earlier timer.

Go / No-Go Criteria

#	Criterion (objectively checkable)	Go	No-Go
1	FlashCardViewModel.flip_card changes the side to the back, the language name to the back language and the text to the translation	Unit test passes	Any other state
2	next_card returns the side to the front	Unit test passes	Side stays on the back
3	The view schedules flip_card with after(3000, ...) and cancels the earlier timer with after_cancel before scheduling a new one	e2e test with a recording scheduler, or a unit test of the view with a fake root	Timer leaks or fires twice
4	The back uses card_back.png and white text; the front uses card_front.png and black text	e2e test reads the canvas item configuration	Any difference
5	PhotoImage objects are created once, outside the callbacks	Code review	An image is created in a function
6	Code review against QC-PY-001 has no failed Mandatory criterion; pytest exits with 0	RC-* verdict Go and exit code 0	Otherwise

Dependencies

Depends on	Reason
MIL-003	Cards with a front and a back to turn

Traceability

Business Case objective / KPI / user story	Reference
Objective 1, step 3	BC-001
US-001.03 See the translation	US-001

Ownership

Role	Stakeholder ID (SA)
Owner	S01
Approving reviewer	S01 (AI as stand-in in autonomous mode)

Target Date

2026-10-17 — within the delivery window that ends 2026-10-21 (BC-001 constraint).

Tasks

#	Task	Summary	Needs its own Use Case/User Story?	Reference
1	Add the card side to the view model	Side enum (front, back) and flip_card on the view model, so the language name and text change with the side without Tkinter.	Yes	US-001.03
2	Flip the card after 3000 ms in the view	FlashCardView.flip_card swaps image, text colour, title and word with itemconfig; flip_timer holds the after id and is cancelled with after_cancel on every button press, as the assignment's hints say.	Yes	US-001.03
3	Test the flip	View model unit tests for both sides, and an e2e test with the real timer replaced by a recording after/after_cancel pair.	No

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