#pragma once
#include <QtGlobal>

// 界面负责取得当前时间，模型只负责计算；测试可传入确定的毫秒数。
class Countdown {
public:
    enum class State { Ready, Running, Paused, Finished };
    explicit Countdown(qint64 durationMs = 300000);
    bool setDuration(qint64 durationMs);
    void start(qint64 nowMs);
    void pause(qint64 nowMs);
    void reset();
    void update(qint64 nowMs);
    qint64 remaining(qint64 nowMs) const;
    qint64 duration() const { return m_duration; }
    State state() const { return m_state; }
private:
    qint64 m_duration;
    qint64 m_remainingAtStart;
    qint64 m_segmentStarted = 0;
    State m_state = State::Ready;
};