extract an Editor class from Window and refactor

1 files changed, 120 insertions, 0 deletions

diff --git a/src/selection.cc b/src/selection.cc
new file mode 100644
index 00000000..e772179c
--- /dev/null
+++ b/src/selection.cc
@@ -0,0 +1,120 @@
+#include "selection.hh"
+
+namespace Kakoune
+{
+
+Selection::Selection(const BufferIterator& first, const BufferIterator& last,
+                     const CaptureList& captures)
+    : m_first(first), m_last(last), m_captures(captures)
+{
+   register_with_buffer();
+}
+
+Selection::Selection(const BufferIterator& first, const BufferIterator& last,
+                     CaptureList&& captures)
+    : m_first(first), m_last(last), m_captures(captures)
+{
+   register_with_buffer();
+}
+
+Selection::Selection(const Selection& other)
+    : m_first(other.m_first), m_last(other.m_last),
+      m_captures(other.m_captures)
+{
+   register_with_buffer();
+}
+
+Selection::Selection(Selection&& other)
+    : m_first(other.m_first), m_last(other.m_last),
+      m_captures(other.m_captures)
+{
+   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;
+   m_captures = other.m_captures;
+
+   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;
+}
+
+BufferString Selection::capture(size_t index) const
+{
+    if (index < m_captures.size())
+        return m_captures[index];
+    return "";
+}
+
+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);
+}
+
+}