web/src/played.ts

// Played-case memory: ids of every case this browser has STARTED, oldest first.
// Sent with New Case so the server never deals this player a mystery they've seen.
const KEY = 'cz-played'
const CAP = 200

interface Stored {
  v: 1
  ids: string[]
}

export function getPlayed(): string[] {
  try {
    const raw = localStorage.getItem(KEY)
    if (!raw) return []
    const data = JSON.parse(raw) as Stored
    if (data?.v !== 1 || !Array.isArray(data.ids)) return []
    return data.ids.filter((x) => typeof x === 'string')
  } catch {
    return []
  }
}

export function markPlayed(id: string): void {
  if (!id) return
  try {
    const ids = getPlayed().filter((x) => x !== id)
    ids.push(id) // most recent last; the server uses order for its repeat-of-last-resort
    localStorage.setItem(KEY, JSON.stringify({ v: 1, ids: ids.slice(-CAP) }))
  } catch {
    /* private mode etc. — repeats become possible, nothing breaks */
  }
}