#include "PrinterStateManager.h"
#include <QDebug>

PrinterStateManager* PrinterStateManager::s_instance = nullptr;

PrinterStateManager* PrinterStateManager::instance()
{
    if (!s_instance) {
        s_instance = new PrinterStateManager();
    }
    return s_instance;
}

PrinterStateManager::PrinterStateManager()
{
    initTransitions();
    m_currentState = PrinterState::IDLE;
}

PrinterStateManager::~PrinterStateManager()
{
}

QString PrinterStateManager::stateName() const
{
    switch (m_currentState) {
    case PrinterState::IDLE: return "空闲";
    case PrinterState::SELF_CHECK: return "自检中";
    case PrinterState::READY: return "就绪";
    case PrinterState::PRINTING: return "打印中";
    case PrinterState::STOPPING: return "停止中";
    case PrinterState::ERROR: return "故障";
    case PrinterState::POWER_OFF: return "关机中";
    default: return "未知";
    }
}

// ============ 初始化状态（开机时调用一次） ============
void PrinterStateManager::initFromSysPara()
{
    setState(PrinterState::SELF_CHECK, "Init from sysPara");
}

// ============ 状态转移表 ============
void PrinterStateManager::initTransitions()
{
    m_transitions = {
        // 开机流程
        {PrinterState::IDLE, PrinterEvent::PowerOn,
         PrinterState::SELF_CHECK, "IDLE → SELF_CHECK", nullptr},
        {PrinterState::SELF_CHECK, PrinterEvent::SelfCheckDone,
         PrinterState::READY, "SELF_CHECK → READY", nullptr},
        {PrinterState::SELF_CHECK, PrinterEvent::SelfCheckFailed,
         PrinterState::ERROR, "SELF_CHECK → ERROR", nullptr},

        // 打印流程
        {PrinterState::READY, PrinterEvent::StartPrint,
         PrinterState::PRINTING, "READY → PRINTING",
        [this]() -> bool { return guardCanStartPrint(); }},

        {PrinterState::PRINTING, PrinterEvent::StopPrint,
         PrinterState::STOPPING, "PRINTING → STOPPING", nullptr},
        {PrinterState::STOPPING, PrinterEvent::StopComplete,
         PrinterState::READY, "STOPPING → READY", nullptr},

        // 错误处理
        {PrinterState::READY, PrinterEvent::ErrorOccurred,
         PrinterState::ERROR, "READY → ERROR", nullptr},
        {PrinterState::PRINTING, PrinterEvent::ErrorOccurred,
         PrinterState::ERROR, "PRINTING → ERROR", nullptr},
        {PrinterState::STOPPING, PrinterEvent::ErrorOccurred,
         PrinterState::ERROR, "STOPPING → ERROR", nullptr},
        {PrinterState::ERROR, PrinterEvent::ErrorCleared,
         PrinterState::READY, "ERROR → READY", nullptr},

        // 关机
        {PrinterState::READY, PrinterEvent::PowerOff,
         PrinterState::POWER_OFF, "READY → POWER_OFF", nullptr},
        {PrinterState::PRINTING, PrinterEvent::PowerOff,
         PrinterState::POWER_OFF, "PRINTING → POWER_OFF", nullptr},
        {PrinterState::STOPPING, PrinterEvent::PowerOff,
         PrinterState::POWER_OFF, "STOPPING → POWER_OFF", nullptr},
        {PrinterState::ERROR, PrinterEvent::PowerOff,
         PrinterState::POWER_OFF, "ERROR → POWER_OFF", nullptr},
        {PrinterState::POWER_OFF, PrinterEvent::PowerOffDone,
         PrinterState::IDLE, "POWER_OFF → IDLE", nullptr},
    };
}

// ============ 查找转移 ============
PrinterStateManager::Transition* PrinterStateManager::findTransition(PrinterEvent event)
{
    for (Transition& trans : m_transitions) {
        if (trans.fromState == m_currentState && trans.event == event) {
            return &trans;
        }
    }
    return nullptr;
}

// ============ 请求切换状态（外部唯一接口） ============
void PrinterStateManager::requestTransition(PrinterEvent event)
{
    qDebug() << "Request event:" << static_cast<int>(event)
             << "Current:" << stateName();

    m_currentState = PrinterState::READY;
    Transition* trans = findTransition(event);
    if (!trans) {
        qDebug() << "Invalid transition, ignored";
        return;
    }

    // 检查守卫条件
    if (trans->guard) {
        bool result = trans->guard();
        if (!result) {
            qDebug() << "Guard condition failed for:" << trans->description;
            return;
        }
    }

    // 执行状态切换（内部管理）
    setState(trans->toState, trans->description);
}

// ============ 内部状态切换 ============
void PrinterStateManager::setState(PrinterState newState, const QString& reason)
{
    if (m_currentState == newState) {
        qDebug() << "State already:" << stateName();
        return;
    }

    m_previousState = m_currentState;
    m_currentState = newState;

    qDebug() << "State changed:" << stateName() << "Reason:" << reason;

    // 发送信号通知外部
    emit sig_stateChanged(newState, m_previousState, reason);
}

// ============ 辅助函数 ============
QString PrinterStateManager::stateNameFromEnum(PrinterState state) const
{
    switch (state) {
    case PrinterState::IDLE: return "IDLE";
    case PrinterState::SELF_CHECK: return "SELF_CHECK";
    case PrinterState::READY: return "READY";
    case PrinterState::PRINTING: return "PRINTING";
    case PrinterState::STOPPING: return "STOPPING";
    case PrinterState::ERROR: return "ERROR";
    case PrinterState::POWER_OFF: return "POWER_OFF";
    default: return "UNKNOWN";
    }
}

// ============ 守卫条件函数 ============

bool PrinterStateManager::guardReclaimTankOpen()
{
    if (!m_sysPara) return false;
    return m_sysPara->status.reclainTankReachEnd == true;
}

bool PrinterStateManager::guardInkSwintOpen()
{
    if (!m_sysPara) return false;
    return !(m_sysPara->status.statWarn & WARN_STATUS_INK_SWINT);
}

bool PrinterStateManager::guardNoError()
{
    if (!m_sysPara) return false;
    return m_sysPara->status.statWarn == 0;
}

bool PrinterStateManager::guardNoInkWarn()
{
    if (!m_sysPara) return false;
    return !(m_sysPara->status.statWarn & WARN_STATUS_INK_WARN);
}

bool PrinterStateManager::guardNoSolventWarn()
{
    if (!m_sysPara) return false;
    return !(m_sysPara->status.statWarn & WARN_STATUS_SOLV_WARN);
}

bool PrinterStateManager::guardSelfCheckDone()
{
    if (!m_sysPara) return false;
    return m_sysPara->status.selfCheckDone == true;
}

bool PrinterStateManager::guardCanStartPrint()
{
    if (!m_sysPara) return false;

    // 自检完成，开回收槽，开墨线，无异常报错
    return guardReclaimTankOpen() && guardInkSwintOpen() &&
            guardNoError() && guardSelfCheckDone();
}