#include "faulttable.h"
#include <QVBoxLayout>
#include <QHBoxLayout>
#include <QTableWidget>
#include <QHeaderView>
#include <QLabel>
#include <QPushButton>
#include <QKeyEvent>
#include "global.h"

FaultTable::FaultTable(QWidget* parent)
    : QWidget(parent)
{
    QVBoxLayout* lay = new QVBoxLayout(this);
    lay->setContentsMargins(0, 0, 0, 0);
    lay->setSpacing(10);

    // 分页行（上一页 / 页码 / 下一页）——水平居中，字号与按钮加大
    QHBoxLayout* nav = new QHBoxLayout();
    nav->setSpacing(50);
    nav->addStretch(1);

    m_prev = new QPushButton("上一页", this);
    m_prev->setFixedSize(240, 100);
    m_prev->setStyleSheet("font-size:50px;");
    connect(m_prev, &QPushButton::clicked, this, [this]() {
        if (m_page > 0) { setPage(m_page - 1); emit pageChanged(m_page); }
    });

    m_pageLabel = new QLabel("1/1", this);
    m_pageLabel->setAlignment(Qt::AlignCenter);
    m_pageLabel->setStyleSheet(QString("color:%1;font-size:40px;").arg(C::TEXT));
    m_pageLabel->setFixedWidth(180);

    m_next = new QPushButton("下一页", this);
    m_next->setFixedSize(240, 100);
    m_next->setStyleSheet("font-size:50px;");
    connect(m_next, &QPushButton::clicked, this, [this]() {
        if (m_page < pageCount() - 1) { setPage(m_page + 1); emit pageChanged(m_page); }
    });

    nav->addWidget(m_prev);
    nav->addWidget(m_pageLabel);
    nav->addWidget(m_next);
    nav->addStretch(1);   // 尾部也留弹性 → 整行居中
    lay->addLayout(nav);

    // 表格
    m_table = new QTableWidget(this);
    m_table->setColumnCount(3);
    m_table->setHorizontalHeaderLabels(QStringList() << "序号" << "故障时间" << "故障名称");
    m_table->setEditTriggers(QAbstractItemView::NoEditTriggers);
    m_table->setSelectionBehavior(QAbstractItemView::SelectRows);
    m_table->setSelectionMode(QAbstractItemView::SingleSelection);
    m_table->setTabKeyNavigation(false);   // 关掉视图自带的 Tab 导航，改由下方 eventFilter 按行切换
    m_table->verticalHeader()->setVisible(false);
    m_table->horizontalHeader()->setFocusPolicy(Qt::NoFocus);   // 表头不参与 Tab
    m_table->verticalHeader()->setFocusPolicy(Qt::NoFocus);
    m_table->setAlternatingRowColors(true);
    m_table->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch);
    m_table->horizontalHeader()->setSectionResizeMode(0, QHeaderView::Fixed);
    m_table->setColumnWidth(0, 120);
    m_table->horizontalHeader()->setSectionResizeMode(2, QHeaderView::Stretch);
    m_table->horizontalHeader()->setFixedHeight(kHeaderHeight);   // 固定表头高度（供对齐）
    // 每页 6 行等分填满表格可用高度，行高由视口高度直接算出（见 updateRowHeights）。
    // 不能用 Stretch：它不会把行压到 minimumSectionSize 之下，而该值默认取自字体度量，
    // 主板上 QSS 指定的中文字体（微软雅黑等）都不存在、回退字体的行高更大，6 行塞不进
    // 视口就会出滚动条、只看得到 5 行。改为固定行高后与字体无关。
    m_table->verticalHeader()->setSectionResizeMode(QHeaderView::Fixed);
    m_table->verticalHeader()->setMinimumSectionSize(1);
    m_table->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    connect(m_table, &QTableWidget::cellClicked, this, [this](int row, int) {
        int global = m_page * m_pageSize + row;
        if (global >= 0 && global < m_data.size())
            emit rowClicked(global);
    });
    m_table->installEventFilter(this);   // 拦截 Tab，实现按行切换
    m_table->viewport()->setMouseTracking(true);      // 悬停整行高亮
    m_table->viewport()->installEventFilter(this);    // 鼠标移出视口 → 取消高亮
    connect(m_table, &QAbstractItemView::entered, this,
            [this](const QModelIndex& idx) { setHoverRow(idx.row()); });
    lay->addWidget(m_table, 1);

    refresh();
}

QWidget* FaultTable::view() const       { return m_table; }
QWidget* FaultTable::prevButton() const { return m_prev; }
QWidget* FaultTable::nextButton() const { return m_next; }

bool FaultTable::eventFilter(QObject* obj, QEvent* ev)
{
    // 视口尺寸变化（含首次布局）后重算行高，保证 6 行恰好铺满。
    // 必须挂在 viewport 上：m_table 收到 Resize 时它的 viewport 还没重排，
    // 那时读到的 viewport 高度是旧值（首次为 0）。
    if (obj == m_table->viewport() && ev->type() == QEvent::Resize) {
        updateRowHeights();
        return QWidget::eventFilter(obj, ev);
    }
    if (obj == m_table->viewport() && ev->type() == QEvent::Leave) {
        setHoverRow(-1);   // 鼠标移出表格 → 取消悬停高亮
        return QWidget::eventFilter(obj, ev);
    }
    if (obj != m_table)
        return QWidget::eventFilter(obj, ev);

    // 焦点进入表格时选中一行：正向(Tab)进末行→回首行、否则选首行；反向(Shift+Tab)同理选末行
    if (ev->type() == QEvent::FocusIn) {
        QFocusEvent* fe = static_cast<QFocusEvent*>(ev);
        const int last = m_table->rowCount() - 1;
        const int col  = qMax(0, m_table->currentColumn());
        int row = -1;
        if (fe->reason() == Qt::TabFocusReason) {
            if (last >= 0 && (m_table->currentRow() < 0 || m_table->currentRow() >= last))
                row = 0;
        } else if (fe->reason() == Qt::BacktabFocusReason) {
            if (last >= 0 && (m_table->currentRow() < 0 || m_table->currentRow() <= 0))
                row = last;
        }
        if (row >= 0) {
            m_table->setCurrentCell(row, col);
            m_table->selectRow(row);   // 显式整行选中（只设当前单元格时可能只高亮一格）
        }
    }

    // 仅键盘(Tab/Shift+Tab)移走焦点时清除选中；鼠标点击/弹窗抢焦点时保留，便于看清当前行
    if (ev->type() == QEvent::FocusOut) {
        QFocusEvent* fe = static_cast<QFocusEvent*>(ev);
        if (fe->reason() == Qt::TabFocusReason || fe->reason() == Qt::BacktabFocusReason)
            m_table->clearSelection();
        return QWidget::eventFilter(obj, ev);
    }

    // Tab / Shift+Tab：按行切换选中（每一行作为一个单位）；空格：等同鼠标点击
    if (ev->type() == QEvent::KeyPress) {
        QKeyEvent* ke = static_cast<QKeyEvent*>(ev);
        const int k = ke->key();
        // 上/下方向键在本机是"旋钮"键位（只给 ParamControl 调值），表格里不参与导航：
        // 换行只走 Tab/Shift+Tab，激活只走空格
        if (Keys::up(k) || Keys::down(k))
            return true;

        if (Keys::tab(k) || Keys::backtab(k)) {
            const bool back = Keys::backtab(k) || Keys::shifted(ke->modifiers());
            const int next = m_table->currentRow() + (back ? -1 : 1);
            if (next >= 0 && next < m_table->rowCount()) {
                m_table->setCurrentCell(next, qMax(0, m_table->currentColumn()));
                m_table->selectRow(next);   // 整行选中
                return true;   // 消费事件，焦点留在表格内
            }
            // 已在首/末行：不拦截，焦点按 Tab 顺序移到下一个控件
        } else if (Keys::space(k)) {
            // 键盘激活：与鼠标 cellClicked 走同一个信号，弹窗逻辑只有一份
            const int row = m_table->currentRow();
            const int global = m_page * m_pageSize + row;
            if (row >= 0 && global >= 0 && global < m_data.size()) {
                emit rowClicked(global);
                return true;
            }
        }
    }
    return QWidget::eventFilter(obj, ev);
}

// 鼠标悬停的整行高亮：颜色与“选中”一致（主色蓝底白字）
void FaultTable::setHoverRow(int row)
{
    if (row == m_hoverRow)
        return;
    if (m_hoverRow >= 0) {
        for (int c = 0; c < m_table->columnCount(); ++c)
            if (QTableWidgetItem* it = m_table->item(m_hoverRow, c)) {
                it->setData(Qt::BackgroundRole, QVariant());
                it->setData(Qt::ForegroundRole, QVariant());
            }
    }
    m_hoverRow = row;
    if (m_hoverRow >= 0) {
        for (int c = 0; c < m_table->columnCount(); ++c)
            if (QTableWidgetItem* it = m_table->item(m_hoverRow, c)) {
                it->setData(Qt::BackgroundRole, QColor(C::PRIMARY));
                it->setData(Qt::ForegroundRole, QColor("#FFFFFF"));
            }
    }
}

void FaultTable::setData(const QVector<FaultRecord>& data)
{
    m_data = data;
    if (m_page >= pageCount() && pageCount() > 0)
        m_page = pageCount() - 1;
    refresh();
}

void FaultTable::setPage(int p)
{
    m_page = qBound(0, p, qMax(0, pageCount() - 1));
    refresh();
}

int FaultTable::pageCount() const
{
    if (m_data.isEmpty()) return 1;
    return (m_data.size() + m_pageSize - 1) / m_pageSize;
}

void FaultTable::refresh()
{
    m_hoverRow = -1;   // 单元格会重建，悬停行失效
    m_table->setRowCount(0);
    m_table->setRowCount(m_pageSize);

    int start = m_page * m_pageSize;
    for (int r = 0; r < m_pageSize; ++r) {
        int idx = start + r;
        bool has = idx < m_data.size();
        for (int c = 0; c < 3; ++c) {
            QTableWidgetItem* it = new QTableWidgetItem();
            it->setTextAlignment(Qt::AlignCenter);
            if (has) {
                const FaultRecord& rec = m_data[idx];
                if (c == 0) it->setText(QString::number(idx + 1));
                else if (c == 1) it->setText(rec.time);
                else it->setText(rec.desc);
            }
            m_table->setItem(r, c, it);
        }
    }

    // 空数据显示提示
    if (m_data.isEmpty()) {
        m_table->clearSelection();
    }

    m_pageLabel->setText(QString("%1/%2").arg(m_page + 1).arg(pageCount()));
    m_prev->setEnabled(m_page > 0);
    m_next->setEnabled(m_page < pageCount() - 1);
}

// 行高 = 视口高度 / 每页行数：6 行恰好铺满，不出现滚动条，也不受字体度量影响
void FaultTable::updateRowHeights()
{
    const int h = m_table->viewport()->height();
    if (h <= 0 || m_pageSize <= 0)
        return;
    m_table->verticalHeader()->setDefaultSectionSize(qMax(1, h / m_pageSize));
}