History and copies

tilttek/deck-builder

Versions

Decks::save($deck, $at, $note = null) saves the deck as its next version, from 1: a DeckVersion with the deck as it was, the moment in UTC and an optional note of up to 500 characters — "after the regional". A version is never rewritten. A deck that has not changed since its latest version keeps that version, so saving on each change of a form is safe.

Two requests that save the same deck at once ask the store to add the same version: the store keeps the first, and the second throws DeckConflict, for the application to read the deck again.

Method	Gives
`latest($deck)`	The latest version
`version($deck, $version)`	A given version
`history($deck)`	Every version, from the first to the latest

A deck with no saved version, or without the version asked, throws UnknownDeck.

Differences

Decks::diff($deck, $from, $to) gives the DeckDiff between two versions, in either order; DeckDiff::between() compares any two decks. It lists the cards added, removed and changed in quantity, and whether the name or the format changed; lines() writes them for people to read:

+2 ember-fox
-1 fox-den
storm-call: 2 → 1
Name: "Foxes" → "Foxes II"

Copies

Decks::copy($deck, $as, $name, $at, $version = null) copies a version of a deck — its latest by default — as the first version of a new deck of identifier $as, whose copiedFrom is a DeckReference to the original deck and version. The copy keeps the original's format and cards; the original is never changed. An identifier already used throws DeckConflict.

The link stays with the copy and its later versions, so an application can show where a deck comes from and count the copies of a published deck.