import { parseStamp } from './statusPush.js'

/** Reject stale updates per order; different orders may share a scan timestamp. */
export function acceptWorkOrderDelta(seen, event) {
    const stamp = parseStamp(event && event.serverUpdatedAt)
    const current = seen || {}
    if (stamp === null || !event || !Array.isArray(event.items)) return { seen: current, items: [] }
    const next = Object.assign(Object.create(null), current)
    const items = event.items.filter((item) => {
        if (!item || !item.code || (next[item.code] !== undefined && stamp <= next[item.code])) return false
        next[item.code] = stamp
        return true
    })
    return { seen: items.length ? next : current, items }
}