kakoune/src/selection.cc

97 lines
2.1 KiB
C++

#include "selection.hh"
namespace Kakoune
{
Selection::Selection(const BufferIterator& first, const BufferIterator& last)
: m_first(first), m_last(last)
{
register_with_buffer();
}
Selection::Selection(const Selection& other)
: m_first(other.m_first), m_last(other.m_last)
{
register_with_buffer();
}
Selection::~Selection()
{
unregister_with_buffer();
}
Selection& Selection::operator=(const Selection& other)
{
const bool new_buffer = &m_first.buffer() != &other.m_first.buffer();
if (new_buffer)
unregister_with_buffer();
m_first = other.m_first;
m_last = other.m_last;
if (new_buffer)
register_with_buffer();
return *this;
}
BufferIterator Selection::begin() const
{
return std::min(m_first, m_last);
}
BufferIterator Selection::end() const
{
return std::max(m_first, m_last) + 1;
}
void Selection::merge_with(const Selection& selection)
{
if (m_first <= m_last)
m_first = std::min(m_first, selection.m_first);
else
m_first = std::max(m_first, selection.m_first);
m_last = selection.m_last;
}
static void update_iterator(const Modification& modification,
BufferIterator& iterator)
{
if (iterator < modification.position)
return;
size_t length = modification.content.length();
if (modification.type == Modification::Erase)
{
// do not move length on the other side of the inequality,
// as modification.position + length may be after buffer end
if (iterator - length <= modification.position)
iterator = modification.position;
else
iterator -= length;
}
else
{
assert(modification.type == Modification::Insert);
iterator += length;
}
}
void Selection::on_modification(const Modification& modification)
{
update_iterator(modification, m_first);
update_iterator(modification, m_last);
}
void Selection::register_with_buffer()
{
const_cast<Buffer&>(m_first.buffer()).register_modification_listener(this);
}
void Selection::unregister_with_buffer()
{
const_cast<Buffer&>(m_first.buffer()).unregister_modification_listener(this);
}
}