#include "CTextItem.h"

#include <QKeyEvent>
#include <QGraphicsSceneMouseEvent>
#include <QTextDocument>
#include <QPainter>
#include <QTextCursor>
#include <QCursor>

#include <QDebug>

CTextItem::CTextItem(QGraphicsItem *parent) : CTextItem(QString(), parent) { }

CTextItem::CTextItem(const QString &text, QGraphicsItem *parent) : QGraphicsTextItem(text, parent)
{
    setFlags(QGraphicsItem::ItemIsFocusable | QGraphicsItem::ItemIsSelectable);
    setTextInteractionFlags(Qt::TextEditorInteraction);
    connect(document(), &QTextDocument::contentsChanged, this, &CTextItem::slotTextChanged);
    connect(document(), &QTextDocument::contentsChange, this, &CTextItem::slotTextChange);
}

void CTextItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {  //左键双击进入可编辑状态并打开焦点
        if (allowEdit()) {
            emit sigWillBeginEditing();
            beginEditing();
        }
        QGraphicsTextItem::mouseDoubleClickEvent(event);
    }
}

void CTextItem::keyPressEvent(QKeyEvent *event)
{
    switch (event->key()) {
    case Qt::Key_Return: {
        endEditing();
    }
    }

    QGraphicsTextItem::keyPressEvent(event);
}

void CTextItem::beginEditing()
{
    setTextInteractionFlags(Qt::TextEditorInteraction);
    setFocus();
    parentItem()->setZValue(-1);
}

void CTextItem::endEditing()
{
    setZValue(0);
    setTextInteractionFlags(Qt::NoTextInteraction);

    setSelected(false);
    clearFocus();

    if (m_textChanged) {
        emit sigTextChanged();
        m_textChanged = false;
    }

    // 没找到取消文字选中状态的方法, 暂且用这个吧
    // 因为这相当于编辑了文字, 会触发数据库保存操作
    setPlainText(toPlainText());
}

bool CTextItem::isEditing() const
{
    return (textInteractionFlags() & Qt::TextEditorInteraction) == Qt::TextEditorInteraction;
}

bool CTextItem::allowEdit() const
{
    return m_allowEdit;
}

void CTextItem::setAllowEdit(bool a)
{
    m_allowEdit = a;
    if (a == false) {
        endEditing();
    }
}

QSizeF CTextItem::textSize(const QString t, qreal width)
{
    static CTextItem *i = nullptr;
    if (i == nullptr) {
        i = new CTextItem(nullptr);
    }

    i->document()->setPlainText(t);
    i->setTextWidth(width);

    return i->document()->size();
}

void CTextItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
    QGraphicsTextItem::paint(painter, option, widget);
}

void CTextItem::slotTextChanged()
{
    m_textChanged = true;
}

void CTextItem::slotTextChange(int from, int charsRemoved, int charsAdded)
{
    Q_UNUSED(from)
    Q_UNUSED(charsRemoved)
    Q_UNUSED(charsAdded)
    QTextCursor c = textCursor();
    if (toPlainText().contains(" ")) {
        setPlainText(toPlainText().remove(QRegExp("\\s")));
        setTextCursor(c);
    }
}