#include "hmieditorwidget.h"
#include "hmibutton.h"
#include "hmiled.h"
#include "hmicontrolitem.h"

#include <QVBoxLayout>
#include <QContextMenuEvent>
#include <QMenu>
#include <QMetaObject>
#include <QGraphicsView>
#include <QApplication>
#include <QClipboard>

HmiEditorWidget::HmiEditorWidget(QWidget* parent)
    : EditorWidget(parent)
{
    // 左侧：在父类 EditorWidget 的左侧工具栏区域追加页面按钮与标签
    QLayoutItem* item = layout()->itemAt(0)->widget()->layout()->itemAt(0);
    auto* leftLayout = dynamic_cast<QVBoxLayout*>(item->layout());

    m_newPageButton    = new QPushButton("新建页面", this);
    m_deletePageButton = new QPushButton("删除页面", this);
    m_prevPageButton   = new QPushButton("上一页", this);
    m_nextPageButton   = new QPushButton("下一页", this);
    m_pageLabel        = new QLabel("无页面", this);

    leftLayout->addWidget(m_newPageButton);
    leftLayout->addWidget(m_deletePageButton);
    leftLayout->addWidget(m_prevPageButton);
    leftLayout->addWidget(m_nextPageButton);
    leftLayout->addWidget(m_pageLabel);
    leftLayout->addStretch();

    connect(m_newPageButton,    &QPushButton::clicked, this, &HmiEditorWidget::onNewPageClicked);
    connect(m_deletePageButton, &QPushButton::clicked, this, &HmiEditorWidget::onDeletePageClicked);
    connect(m_prevPageButton,   &QPushButton::clicked, this, &HmiEditorWidget::onPreviousPageClicked);
    connect(m_nextPageButton,   &QPushButton::clicked, this, &HmiEditorWidget::onNextPageClicked);

    // 工具栏项
    initToolbar();

    // 确保视图已创建（父类提供）
    ensureViewReady();

    // 捕获编辑区鼠标：既监听 QGraphicsView 自身，也监听其 viewport
    if (editArea) {
        editArea->installEventFilter(this);
        if (editArea->viewport())
            editArea->viewport()->installEventFilter(this);
    }
}

HmiEditorWidget::~HmiEditorWidget() {
    clearPages();
}

void HmiEditorWidget::refreshView()
{
    if (m_currentPageIndex >= 0 && !m_pages.isEmpty()) {
        editArea->setScene(nullptr);
        editArea->setScene(m_pages[m_currentPageIndex]);
        initViewScale();
        editArea->viewport()->update();
    }
}

void HmiEditorWidget::initToolbar() {
    // “按钮”
    auto* buttonItem = new QListWidgetItem();
    buttonItem->setIcon(QIcon(":resource/image/button.png"));
    buttonItem->setData(Qt::UserRole, QString("按钮"));
    buttonItem->setToolTip("按钮");
    toolbar->addItem(buttonItem);

    // “指示灯”
    auto* ledItem = new QListWidgetItem();
    ledItem->setIcon(QIcon(":resource/image/light.png"));
    ledItem->setData(Qt::UserRole, QString("指示灯"));
    ledItem->setToolTip("指示灯");
    toolbar->addItem(ledItem);
}

void HmiEditorWidget::onToolbarItemClicked(QListWidgetItem* item) {
    if (!item) return;

    // —— 关键改动 ——：
    // 不再“立即创建到场景中心”，而是进入“放置模式”
    m_pendingType = item->data(Qt::UserRole).toString();
    setPlacingCursor(true);

    appendOutput(QString("已选择控件：%1。请在编辑区点击以放置。").arg(m_pendingType));
}

QGraphicsScene* HmiEditorWidget::getCurrentScene() const {
    if (m_currentPageIndex >= 0 && m_currentPageIndex < m_pages.size())
        return m_pages[m_currentPageIndex];
    return nullptr;
}

void HmiEditorWidget::clearPages() {
    for (QGraphicsScene* scene : m_pages) delete scene;
    m_pages.clear();
    m_currentPageIndex = -1;
    if (editArea) editArea->setScene(nullptr);
    updatePageLabel();
}

void HmiEditorWidget::createNewPage()
{
    auto* newScene = new QGraphicsScene(this);
    QRect viewRect = editArea->viewport()->rect();
    if (viewRect.isEmpty()) {
        viewRect = QRect(0,0,800,600);
        editArea->setSceneRect(viewRect);
    }

    newScene->setSceneRect(viewRect);
    m_pages.append(newScene);
    m_currentPageIndex = m_pages.size() - 1;

    QMetaObject::invokeMethod(this, [this, newScene](){
        editArea->setScene(newScene);
        initViewScale();
        updatePageLabel();
        editArea->viewport()->update();
    }, Qt::QueuedConnection);
}

void HmiEditorWidget::switchToPage(int index) {
    if (index >= 0 && index < m_pages.size()) {
        m_currentPageIndex = index;
        editArea->resetTransform();
        editArea->setScene(m_pages[index]);
        updatePageLabel();
        QMetaObject::invokeMethod(this, [this](){
            initViewScale();
            editArea->viewport()->update();
        }, Qt::QueuedConnection);
    }
}

void HmiEditorWidget::initViewScale()
{
    if (!editArea || m_currentPageIndex < 0 || m_pages.isEmpty()) return;

    QRect viewRect = editArea->viewport()->rect();
    if (viewRect.isEmpty()) viewRect = QRect(0,0,800,600);

    auto* currentScene = m_pages[m_currentPageIndex];
    QRectF currentRect = currentScene->sceneRect();
    const qreal newW = qMax(currentRect.width(),  qreal(viewRect.width()));
    const qreal newH = qMax(currentRect.height(), qreal(viewRect.height()));
    currentScene->setSceneRect(0,0,newW,newH);

    editArea->viewport()->update();
}

void HmiEditorWidget::updatePageLabel()
{
    if (m_pages.isEmpty()) {
        m_pageLabel->setText("无页面");
        m_deletePageButton->setEnabled(false);
        m_prevPageButton->setEnabled(false);
        m_nextPageButton->setEnabled(false);
    } else {
        m_pageLabel->setText(QString("第 %1/%2 页").arg(m_currentPageIndex+1).arg(m_pages.size()));
        m_deletePageButton->setEnabled(m_pages.size()>1);
        m_prevPageButton->setEnabled(m_currentPageIndex>0);
        m_nextPageButton->setEnabled(m_currentPageIndex<m_pages.size()-1);
    }
}

bool HmiEditorWidget::eventFilter(QObject* obj, QEvent* event)
{
    // —— 右键空白处：弹出“粘贴”菜单（保留原逻辑） —— //
    if (obj == editArea && event->type() == QEvent::ContextMenu) {
        auto* contextEvent = static_cast<QContextMenuEvent*>(event);
        if (m_currentPageIndex >= 0 && m_pages[m_currentPageIndex]) {
            QGraphicsItem* hit = editArea->itemAt(contextEvent->pos());
            if (!hit) {
                QMenu menu;
                QAction* pasteAction = new QAction("粘贴", &menu);
                pasteAction->setEnabled(HmiControlItem::hasClipboardData());
                connect(pasteAction, &QAction::triggered, [this, contextEvent](){
                    if (m_currentPageIndex >= 0 && m_pages[m_currentPageIndex] &&
                        HmiControlItem::hasClipboardData()) {

                        const QPointF scenePos = editArea->mapToScene(contextEvent->pos());
                        HmiControlItem* newItem =
                            HmiControlItem::createFromClipboard(HmiControlItem::getClipboardData(), scenePos);
                        if (newItem) {
                            m_pages[m_currentPageIndex]->addItem(newItem);
                            m_pages[m_currentPageIndex]->clearSelection();
                            newItem->setSelected(true);
                            editArea->viewport()->update();
                        }
                    }
                });
                menu.addAction(pasteAction);
                menu.exec(contextEvent->globalPos());
            }
        }
        return true;
    }

    // —— 关键改动：放置模式下，点击编辑区创建 —— //
    // 捕获 QGraphicsView 的 viewport 左键按下
    if (obj == (editArea ? editArea->viewport() : nullptr)
        && event->type() == QEvent::MouseButtonPress && !m_pendingType.isEmpty()) {

        auto* me = static_cast<QMouseEvent*>(event);
        if (me->button() == Qt::LeftButton
            && m_currentPageIndex >= 0
            && m_pages[m_currentPageIndex]) {

            const QPointF scenePos = editArea->mapToScene(me->pos());
            HmiControlItem* item = createItemByType(m_pendingType, scenePos);
            if (item) {
                m_pages[m_currentPageIndex]->addItem(item);
                m_pages[m_currentPageIndex]->clearSelection();
                item->setSelected(true);
                editArea->viewport()->update();
            }
            // 一次放一个：退出放置模式（如需连续放置，注释掉两行）
            m_pendingType.clear();
            setPlacingCursor(false);

            return true; // 已处理
        }
    }

    return EditorWidget::eventFilter(obj, event);
}

void HmiEditorWidget::resizeEvent(QResizeEvent* e) {
    EditorWidget::resizeEvent(e);
    if (m_currentPageIndex >= 0 && !m_pages.isEmpty()) initViewScale();
}

void HmiEditorWidget::showEvent(QShowEvent* e) {
    EditorWidget::showEvent(e);
    if (m_pages.isEmpty()) createNewPage();
}

void HmiEditorWidget::keyPressEvent(QKeyEvent* event)
{
    // Ctrl+C：复制（保留原逻辑——复制首个选中项至静态剪贴板）
    if (event->matches(QKeySequence::Copy)) {
        if (m_currentPageIndex >= 0 && m_pages[m_currentPageIndex]) {
            auto selectedItems = m_pages[m_currentPageIndex]->selectedItems();
            if (!selectedItems.isEmpty()) {
                if (auto* item = dynamic_cast<HmiControlItem*>(selectedItems.first())) {
                    HmiControlItem::copyToClipboard(item->saveToClipboard());
                }
            }
        }
        return;
    }

    // Ctrl+V：粘贴（关键改动：若有选中源控件 → 旁边粘贴；否则 → 场景中心）
    if (event->matches(QKeySequence::Paste)) {
        if (m_currentPageIndex >= 0 &&
            m_pages[m_currentPageIndex] &&
            HmiControlItem::hasClipboardData()) {

            QPointF pastePos;
            auto selectedItems = m_pages[m_currentPageIndex]->selectedItems();
            static int s_pasteIndex = 0; // 连续多次粘贴时，用来轻微错行

            if (!selectedItems.isEmpty()) {
                if (auto* src = dynamic_cast<HmiControlItem*>(selectedItems.first())) {
                    pastePos = calcPasteBesidePos(src, s_pasteIndex++);
                }
            } else {
                // 无选中项：仍按原逻辑 → 场景中心
                QRectF rect = m_pages[m_currentPageIndex]->sceneRect();
                pastePos = QPointF(rect.width()/2, rect.height()/2);
                s_pasteIndex = 0;
            }

            HmiControlItem* newItem =
                HmiControlItem::createFromClipboard(HmiControlItem::getClipboardData(), pastePos);
            if (newItem) {
                m_pages[m_currentPageIndex]->addItem(newItem);
                m_pages[m_currentPageIndex]->clearSelection();
                newItem->setSelected(true);
                editArea->viewport()->update();
            }
        }
        return;
    }

    // Delete：删除（保留原逻辑）
    if (event->matches(QKeySequence::Delete)) {
        if (m_currentPageIndex >= 0 && m_pages[m_currentPageIndex]) {
            auto selectedItems = m_pages[m_currentPageIndex]->selectedItems();
            for (QGraphicsItem* gi : selectedItems) {
                if (auto* ci = dynamic_cast<HmiControlItem*>(gi)) ci->deleteItem();
            }
            editArea->viewport()->update();
        }
        return;
    }

    EditorWidget::keyPressEvent(event);
}

void HmiEditorWidget::onNewPageClicked() { createNewPage(); }

void HmiEditorWidget::onDeletePageClicked() {
    if (m_currentPageIndex >= 0 && m_pages.size() > 1) {
        QGraphicsScene* scene = m_pages[m_currentPageIndex];
        m_pages.removeAt(m_currentPageIndex);
        delete scene;

        m_currentPageIndex = qMin(m_currentPageIndex, m_pages.size()-1);
        editArea->setScene(m_pages[m_currentPageIndex]);
        initViewScale();
        updatePageLabel();
        editArea->viewport()->update();
        appendOutput(QString("删除页面，剩余页面数: %1").arg(m_pages.size()));
    }
}

void HmiEditorWidget::onPreviousPageClicked() { switchToPage(m_currentPageIndex - 1); }
void HmiEditorWidget::onNextPageClicked()     { switchToPage(m_currentPageIndex + 1); }

// —— 私有辅助 —— //

HmiControlItem* HmiEditorWidget::createItemByType(const QString& type, const QPointF& scenePos)
{
    HmiControlItem* item = nullptr;
    if (type == "按钮") {
        item = new HmiButton();
        appendOutput("添加按钮控件");
    } else if (type == "指示灯") {
        item = new HmiLed();
        appendOutput("添加指示灯控件");
    }
    if (item) item->setPos(scenePos);
    return item;
}

void HmiEditorWidget::setPlacingCursor(bool on)
{
    if (!editArea) return;
    if (on) {
        editArea->setCursor(Qt::CrossCursor);
        if (editArea->viewport()) editArea->viewport()->setCursor(Qt::CrossCursor);
    } else {
        editArea->unsetCursor();
        if (editArea->viewport()) editArea->viewport()->unsetCursor();
    }
}

QPointF HmiEditorWidget::calcPasteBesidePos(HmiControlItem* src, int pasteIndex) const
{
    if (!src) return QPointF();

    // 使用“映射到场景后的边界框”来获取可视宽度，避免缩放带来的误差
    QRectF sceneRect = src->mapToScene(src->boundingRect()).boundingRect();
    const qreal w = qMax<qreal>(sceneRect.width(), 24.0); // 保底宽度
    const qreal gap = 12.0;   // 与原件的水平间隔
    const qreal stepY = 8.0;  // 连续粘贴时的竖向微调

    QPointF base = src->pos();
    return QPointF(base.x() + w + gap, base.y() + pasteIndex * stepY);
}