#include "operationCommand.h"
#include <QGraphicsItem>

AddItemCommand::AddItemCommand(QGraphicsItem* item, QGraphicsScene* scene, QUndoCommand* parent)
    : QUndoCommand(parent)
{
    m_pItem = item;
    m_itemPos = item->pos();
    m_pGraphicsScene = scene;
}
AddItemCommand::~AddItemCommand()
{
}
void AddItemCommand::undo()
{
    m_pGraphicsScene->removeItem(m_pItem);
    m_pGraphicsScene->update();
}
void AddItemCommand::redo()
{
    if(m_pItem->scene()) //因为添加图元后同步创建一条该指令，平且在push进入stack的时候redo会被触发一次，因此这里加判断，防止重复操作
        return;

    m_pGraphicsScene->addItem(m_pItem);
    m_pItem->setPos(m_itemPos);
    m_pGraphicsScene->update();
}

DeleteItemCommand::DeleteItemCommand(QGraphicsScene* scene, QUndoCommand* parent)
    : QUndoCommand(parent)
{
    m_pGraphicsScene = scene;
    m_listItem = scene->selectedItems();
}
DeleteItemCommand::~DeleteItemCommand()
{
}
void DeleteItemCommand::undo()
{
    foreach(QGraphicsItem* item, m_listItem)
    {
        QGraphicsItemGroup* group = dynamic_cast<QGraphicsItemGroup*>(item->parentItem());
        if(!group)
        {
            m_pGraphicsScene->addItem(item);
        }
    }

    m_pGraphicsScene->update();
}
void DeleteItemCommand::redo()
{
    foreach(QGraphicsItem* item, m_listItem)
    {
        QGraphicsItemGroup* group = dynamic_cast<QGraphicsItemGroup*>(item->parentItem());
        if(!group)
        {
            m_pGraphicsScene->removeItem(item); //remove即可，不要delete，因为会影响撤回（undo）操作
        }
    }

    m_pGraphicsScene->update();
}