ladybird/Userland/Libraries/LibGUI/UndoStack.cpp
2021-01-12 12:17:46 +01:00

103 lines
3 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <LibGUI/Command.h>
#include <LibGUI/UndoStack.h>
namespace GUI {
UndoStack::UndoStack()
{
}
UndoStack::~UndoStack()
{
}
void UndoStack::undo()
{
if (!can_undo())
return;
auto pop_container_and_undo = [this]() {
for (;;) {
if (m_stack_index >= m_stack.size())
break;
auto& container = m_stack[m_stack_index++];
if (container.m_undo_vector.size() == 0)
continue;
for (auto& command : container.m_undo_vector)
command.undo();
break;
}
};
// If this is the first undo, finish off our current combo
if (m_stack_index == 0)
finalize_current_combo();
pop_container_and_undo();
}
void UndoStack::redo()
{
if (!can_redo())
return;
m_stack_index -= 1;
auto& vector = m_stack[m_stack_index].m_undo_vector;
for (int i = vector.size() - 1; i >= 0; i--)
vector[i].redo();
}
void UndoStack::push(NonnullOwnPtr<Command>&& command)
{
if (m_stack.is_empty())
finalize_current_combo();
if (m_stack_index > 0) {
for (size_t i = 0; i < m_stack_index; i++)
m_stack.remove(0);
m_stack_index = 0;
finalize_current_combo();
}
auto& current_vector = m_stack.first().m_undo_vector;
current_vector.prepend(move(command));
}
void UndoStack::finalize_current_combo()
{
if (m_stack_index > 0)
return;
if (m_stack.size() != 0 && m_stack.first().m_undo_vector.size() == 0)
return;
auto undo_commands_container = make<UndoCommandsContainer>();
m_stack.prepend(move(undo_commands_container));
}
}