【框架设计】答题活动：题库轮换与防作弊

function Quiz.pushQuestion(plr, qid)
    local q = QUIZ_POOL[qid]
    local order = shuffle({ 1, 2, 3, 4 })
    plr.quizState = { qid = qid, askedAt = os.time(), order = order }
    QF_SendQuiz(plr, {
        text = q.text,
        options = { q.opts[order[1]], q.opts[order[2]], q.opts[order[3]], q.opts[order[4]] },
    })
end

function Quiz.answer(plr, optIndex)
    local st = plr.quizState
    if not st then return false end
    if os.time() - st.askedAt < 2 then
        QF_AlarmQuiz(plr.id, "作答过快")
        return false
    end
    local q = QUIZ_POOL[st.qid]
    local correct = st.order[optIndex] == q.answer
    if correct then plr.quizScore = (plr.quizScore or 0) + 1 end
    plr.quizState = nil
    return correct
end