#include "chatview.h"
#include "qdebug.h"
#include "qmenu.h"
#include "widgets/chatView/chat1/chatmessage.h"

#include <QApplication>
#include <QClipboard>
#include <QMouseEvent>
#include <QPixmap>
#include <QTimer>
#include <utility>

// 在构造函数中添加
ChatView::ChatView(QWidget *parent)
    : QListView(parent)
    , m_selecting(false)
{
    m_model = new ChatMessageModel(this);
    m_delegate = new ChatMessageDelegate(this);

    setModel(m_model);
    setItemDelegate(m_delegate);

    setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
    setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
    setSpacing(0);

    // 启用文本选择
    setSelectionMode(QAbstractItemView::ExtendedSelection);
    setTextElideMode(Qt::ElideNone);

    // 优化性能
    setUniformItemSizes(false);

    // 设置鼠标追踪，以支持文本选择
    setMouseTracking(true);
    
    // 创建右键菜单
    m_contextMenu = new QMenu(this);
    QAction *copyAction = m_contextMenu->addAction("复制");
    connect(copyAction, &QAction::triggered, this, &ChatView::copySelectedText);

    connect(this,
            &ChatView::viewportWidthChanged,
            m_delegate,
            &ChatMessageDelegate::setViewportWidth);

    setMinimumWidth(ChatConstants::BUBBLE_PADDING + ChatConstants::AVATAR_SIZE + 150
                    + ChatConstants::AVATAR_SIZE + ChatConstants::BUBBLE_PADDING);
}

void ChatView::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        m_selecting = true;
        QModelIndex index = indexAt(event->pos());
        if (index.isValid()) {
            const ChatMessage &message = index.data().value<ChatMessage>();

            // 系统消息不支持选择
            if (message.type == MessageType::System) {
                m_selecting = false;
                QListView::mousePressEvent(event);
                return;
            }

            m_currentMessageIndex = index;
            QRect itemRect = visualRect(index);
            QPoint relativePos = event->pos() - itemRect.topLeft();

            // 计算文本区域的偏移
            if (message.type == MessageType::Left) {
                relativePos.rx() -= (ChatConstants::AVATAR_SIZE + 2 * ChatConstants::BUBBLE_SPACING);
            } else {
                // 右侧消息需要特殊处理
                QSize textSize = m_delegate->calculateTextSize(fontMetrics(), message.text);
                int bubbleWidth = textSize.width() + 2 * ChatConstants::BUBBLE_PADDING;
                relativePos.rx() -= (itemRect.width() - bubbleWidth - ChatConstants::AVATAR_SIZE
                                     - 2 * ChatConstants::BUBBLE_SPACING);
            }

            // 调整相对于文本的位置
            relativePos.rx() -= ChatConstants::BUBBLE_PADDING;
            relativePos.ry() -= ChatConstants::BUBBLE_PADDING;

            // 通过委托计算文本位置
            int pos = m_delegate->getPositionFromPoint(relativePos, message.text, fontMetrics());

            // 优化：如果点击位置在气泡内但不在文本上，或者位置小于等于0，则选择从第一个字符开始
            if (pos <= 0                                             //
                && relativePos.x() >= -ChatConstants::BUBBLE_PADDING //
                && relativePos.y() >= -ChatConstants::BUBBLE_PADDING //
                && relativePos.x() <= message.text.length() * 8 &&   // 粗略估计文本宽度
                relativePos.y() <= fontMetrics().height() * (message.text.count('\n') + 1)) {
                pos = 0; // 从第一个字符开始选择
            }

            // 确保点击位置有效，才设置选择起点
            if (pos >= 0 && pos <= message.text.length()) {
                m_selectionStartPos = pos;
                m_selectionEndPos = pos;

                // 更新委托的选择信息
                m_delegate->setSelectionRange(m_selectionStartPos, m_selectionEndPos);
                m_delegate->setCurrentMessageIndex(m_currentMessageIndex);

                // 设置当前选中项
                setCurrentIndex(index);
                update(index); // 重绘当前项
            } else {
                // 点击在文本区域外，不进行选择
                m_selecting = false;
            }
        } else {
            // 点击空白区域，清除选择
            m_selectionStartPos = -1;
            m_selectionEndPos = -1;
            m_currentMessageIndex = QModelIndex();
            m_delegate->setSelectionRange(-1, -1);
            m_delegate->setCurrentMessageIndex(QModelIndex());
        }
    }
    QListView::mousePressEvent(event);
}

void ChatView::mouseMoveEvent(QMouseEvent *event)
{
    if (m_selecting && m_currentMessageIndex.isValid()) {
        QRect itemRect = visualRect(m_currentMessageIndex);
        QPoint relativePos = event->pos() - itemRect.topLeft();

        // 计算文本区域的偏移
        const ChatMessage &message = m_currentMessageIndex.data().value<ChatMessage>();

        // 系统消息不支持选择
        if (message.type == MessageType::System) {
            return;
        }

        if (message.type == MessageType::Left) {
            relativePos.rx() -= (ChatConstants::AVATAR_SIZE + 2 * ChatConstants::BUBBLE_SPACING);
        } else {
            // 右侧消息需要特殊处理
            QSize textSize = m_delegate->calculateTextSize(fontMetrics(), message.text);
            int bubbleWidth = textSize.width() + 2 * ChatConstants::BUBBLE_PADDING;
            relativePos.rx() -= (itemRect.width() - bubbleWidth - ChatConstants::AVATAR_SIZE
                                 - 2 * ChatConstants::BUBBLE_SPACING);
        }

        // 调整相对于文本的位置
        relativePos.rx() -= ChatConstants::BUBBLE_PADDING;
        relativePos.ry() -= ChatConstants::BUBBLE_PADDING;

        int newPos = m_delegate->getPositionFromPoint(relativePos, message.text, fontMetrics());

        // 确保新位置有效
        if (newPos >= 0 && newPos <= message.text.length()) {
            m_selectionEndPos = newPos;
            // 更新委托的选择信息
            m_delegate->setSelectionRange(m_selectionStartPos, m_selectionEndPos);
            update(m_currentMessageIndex); // 重绘当前项
        }
    }

    QListView::mouseMoveEvent(event);
}

// 新增上下文菜单事件
void ChatView::contextMenuEvent(QContextMenuEvent *event)
{
    if (m_currentMessageIndex.isValid() && m_selectionStartPos >= 0 && m_selectionEndPos >= 0
        && m_selectionStartPos != m_selectionEndPos) {
        m_contextMenu->exec(event->globalPos());
    } else {
        QListView::contextMenuEvent(event);
    }
}

void ChatView::resizeEvent(QResizeEvent *event)
{
    QListView::resizeEvent(event);
    // 当视图大小改变时，通知委托视图宽度已更改
    emit viewportWidthChanged(viewport()->width());

    // 强制更新所有项目的布局，解决重叠问题
    for (int i = 0; i < m_model->rowCount(); ++i) {
        QModelIndex index = m_model->index(i);
        update(index);
    }
    // 强制模型发出数据变化信号，触发重新布局
    if (m_model->rowCount() > 0) {
        m_model->dataChanged(m_model->index(0), m_model->index(m_model->rowCount() - 1));
    }
    // 当视图大小改变时，保持滚动到底部
    if (m_model->rowCount() > 0) {
        QModelIndex lastIndex = m_model->index(m_model->rowCount() - 1);
        scrollTo(lastIndex);
    }
}

// 新增文本获取方法
QString ChatView::getSelectedText() const
{
    if (m_currentMessageIndex.isValid() && m_selectionStartPos >= 0 && m_selectionEndPos >= 0) {
        const ChatMessage message = m_currentMessageIndex.data().value<ChatMessage>();

        // 系统消息不支持选择
        if (message.type == MessageType::System) {
            return QString();
        }

        const QString text = message.text;
        int start = qMin(m_selectionStartPos, m_selectionEndPos);
        int end = qMax(m_selectionStartPos, m_selectionEndPos);

        if (start != end && start >= 0 && end <= text.length()) {
            // 直接提取选中的文本，保留原始格式包括换行符
            return text.mid(start, end - start);
        }
    }
    return QString();
}

// 新增复制方法
void ChatView::copySelectedText()
{
    QString text = getSelectedText();
    if (!text.isEmpty()) {
        QClipboard *clipboard = QApplication::clipboard();
        clipboard->setText(text);
    }
}

void ChatView::scrollToBottom()
{
    QTimer::singleShot(0, this, [this]() {
        if (m_model->rowCount() > 0) {
            scrollTo(m_model->index(m_model->rowCount() - 1), QAbstractItemView::PositionAtBottom);
        }
    });
}
void ChatView::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        m_selecting = false;
    }
    QListView::mouseReleaseEvent(event);
}

void ChatView::keyPressEvent(QKeyEvent *event)
{
    // 处理复制操作
    if (event->matches(QKeySequence::Copy)) {
        QStringList selectedTexts;
        QModelIndexList selection = selectionModel()->selectedIndexes();

        for (const QModelIndex &index : std::as_const(selection)) {
            ChatMessage message = index.data().value<ChatMessage>();
            selectedTexts << message.text;
        }

        if (!selectedTexts.isEmpty()) {
            QClipboard *clipboard = QApplication::clipboard();
            clipboard->setText(selectedTexts.join("\n"));
        }
        event->accept();
        return;
    }
    QListView::keyPressEvent(event);
}
void ChatView::addMessage(const QString &text, const QString &avatar, const QString &senderName, bool isLeft)
{
    ChatMessage message;
    message.text = text;
    message.avatar = avatar;
    message.senderName = senderName;
    message.type = isLeft ? MessageType::Left : MessageType::Right;
    m_model->addMessage(message);
    scrollToBottom();
}

void ChatView::addSystemMessage(const QString &text)
{
    ChatMessage message(text, MessageType::System);
    m_model->addMessage(message);
    scrollToBottom();
}

void ChatView::addImageMessage(const QString &imagePath, const QString &avatar, const QString &senderName, bool isLeft, const QString &text)
{
    // 获取图片尺寸
    QPixmap image(imagePath);
    QSize imageSize = image.isNull() ? QSize(100, 100) : image.size();
    
    ChatMessage message(imagePath, imageSize, isLeft ? MessageType::Left : MessageType::Right, text);
    message.avatar = avatar;
    message.senderName = senderName;
    
    m_model->addMessage(message);
    scrollToBottom();
}

void ChatView::clear()
{
    m_model->clear();
}