kakoune/src/buffer.cc
2013-04-30 19:01:20 +02:00

641 lines
19 KiB
C++

#include "buffer.hh"
#include "assert.hh"
#include "buffer_manager.hh"
#include "context.hh"
#include "file.hh"
#include "utils.hh"
#include "window.hh"
#include <algorithm>
namespace Kakoune
{
Buffer::Buffer(String name, Flags flags, std::vector<String> lines)
: m_name(std::move(name)), m_flags(flags | Flags::NoUndo),
m_history(), m_history_cursor(m_history.begin()),
m_last_save_undo_index(0),
m_timestamp(0),
m_hooks(GlobalHooks::instance()),
m_options(GlobalOptions::instance())
{
BufferManager::instance().register_buffer(*this);
if (flags & Flags::File)
m_name = real_path(m_name);
if (lines.empty())
lines.emplace_back("\n");
ByteCount pos = 0;
m_lines.reserve(lines.size());
for (auto& line : lines)
{
kak_assert(not line.empty() and line.back() == '\n');
m_lines.emplace_back(Line{ pos, std::move(line) });
pos += m_lines.back().length();
}
Editor editor_for_hooks(*this);
Context context(editor_for_hooks);
if (flags & Flags::File)
{
if (flags & Flags::New)
m_hooks.run_hook("BufNew", m_name, context);
else
m_hooks.run_hook("BufOpen", m_name, context);
}
m_hooks.run_hook("BufCreate", m_name, context);
// now we may begin to record undo data
m_flags = flags;
}
Buffer::~Buffer()
{
{
Editor hook_editor{*this};
Context hook_context{hook_editor};
m_hooks.run_hook("BufClose", m_name, hook_context);
}
BufferManager::instance().unregister_buffer(*this);
kak_assert(m_change_listeners.empty());
}
String Buffer::display_name() const
{
if (m_flags & Flags::File)
return compact_path(m_name);
return m_name;
}
bool Buffer::set_name(String name)
{
Buffer* other = BufferManager::instance().get_buffer_ifp(name);
if (other == nullptr or other == this)
{
if (m_flags & Flags::File)
m_name = real_path(name);
else
m_name = std::move(name);
return true;
}
return false;
}
BufferIterator Buffer::iterator_at(const BufferCoord& line_and_column,
bool avoid_eol) const
{
return BufferIterator(*this, clamp(line_and_column, avoid_eol));
}
ByteCount Buffer::line_length(LineCount line) const
{
kak_assert(line < line_count());
ByteCount end = (line < line_count() - 1) ?
m_lines[line + 1].start : byte_count();
return end - m_lines[line].start;
}
BufferCoord Buffer::clamp(const BufferCoord& line_and_column,
bool avoid_eol) const
{
if (m_lines.empty())
return BufferCoord();
BufferCoord result(line_and_column.line, line_and_column.column);
result.line = Kakoune::clamp(result.line, 0_line, line_count() - 1);
ByteCount max_col = std::max(0_byte, line_length(result.line) - (avoid_eol ? 2 : 1));
result.column = Kakoune::clamp(result.column, 0_byte, max_col);
return result;
}
BufferIterator Buffer::iterator_at_line_begin(LineCount line) const
{
line = Kakoune::clamp(line, 0_line, line_count()-1);
kak_assert(line_length(line) > 0);
return BufferIterator(*this, { line, 0 });
}
BufferIterator Buffer::iterator_at_line_begin(const BufferIterator& iterator) const
{
return iterator_at_line_begin(iterator.line());
}
BufferIterator Buffer::iterator_at_line_end(LineCount line) const
{
line = Kakoune::clamp(line, 0_line, line_count()-1);
kak_assert(line_length(line) > 0);
return ++BufferIterator(*this, { line, line_length(line) - 1 });
}
BufferIterator Buffer::iterator_at_line_end(const BufferIterator& iterator) const
{
return iterator_at_line_end(iterator.line());
}
BufferIterator Buffer::begin() const
{
return BufferIterator(*this, { 0_line, 0 });
}
BufferIterator Buffer::end() const
{
if (m_lines.empty())
return BufferIterator(*this, { 0_line, 0 });
return BufferIterator(*this, { line_count()-1, m_lines.back().length() });
}
ByteCount Buffer::byte_count() const
{
if (m_lines.empty())
return 0;
return m_lines.back().start + m_lines.back().length();
}
LineCount Buffer::line_count() const
{
return LineCount(m_lines.size());
}
String Buffer::string(const BufferIterator& begin, const BufferIterator& end) const
{
String res;
for (LineCount line = begin.line(); line <= end.line(); ++line)
{
ByteCount start = 0;
if (line == begin.line())
start = begin.column();
ByteCount count = -1;
if (line == end.line())
count = end.column() - start;
res += m_lines[line].content.substr(start, count);
}
return res;
}
// A Modification holds a single atomic modification to Buffer
struct Buffer::Modification
{
enum Type { Insert, Erase };
Type type;
BufferCoord coord;
String content;
Modification(Type type, BufferCoord coord, String content)
: type(type), coord(coord), content(std::move(content)) {}
Modification inverse() const
{
Type inverse_type = Insert;
switch (type)
{
case Insert: inverse_type = Erase; break;
case Erase: inverse_type = Insert; break;
default: kak_assert(false);
}
return {inverse_type, coord, content};
}
};
class UndoGroupOptimizer
{
static constexpr auto Insert = Buffer::Modification::Type::Insert;
static constexpr auto Erase = Buffer::Modification::Type::Erase;
static BufferCoord advance(BufferCoord coord, const String& str)
{
for (auto c : str)
{
if (c == '\n')
{
++coord.line;
coord.column = 0;
}
else
++coord.column;
}
return coord;
}
static ByteCount count_byte_to(BufferCoord pos, const BufferCoord& endpos, const String& str)
{
ByteCount count = 0;
for (auto it = str.begin(); it != str.end() and pos != endpos; ++it)
{
if (*it == '\n')
{
++pos.line;
pos.column = 0;
}
else
++pos.column;
++count;
}
assert(pos == endpos);
return count;
}
static const ByteCount overlaps(const String& lhs, const String& rhs)
{
if (lhs.empty() or rhs.empty())
return -1;
char c = rhs.front();
ByteCount pos = 0;
while ((pos = (int)lhs.find_first_of(c, (int)pos)) != -1)
{
ByteCount i = pos, j = 0;
while (i != lhs.length() and j != rhs.length() and lhs[i] == rhs[j])
++i, ++j;
if (i == lhs.length())
break;
++pos;
}
return pos;
}
static bool merge_contiguous(Buffer::UndoGroup& undo_group)
{
bool progress = false;
auto it = undo_group.begin();
auto it_next = it+1;
while (it_next != undo_group.end())
{
ByteCount pos;
auto& coord = it->coord;
auto& next_coord = it_next->coord;
// reorders modification doing a kind of custom bubble sort
// so we have a O(n²) worst case complexity of the undo group optimization
if (next_coord < coord)
{
BufferCoord next_end = advance(next_coord, it_next->content);
if (it_next->type == Insert)
{
if (coord.line == next_coord.line)
coord.column += next_end.column - next_coord.column;
coord.line += next_end.line - next_coord.line;
}
else if (it->type == Insert)
{
if (next_end > coord)
{
ByteCount start = count_byte_to(next_coord, coord, it_next->content);
ByteCount len = std::min(it->content.length(), it_next->content.length() - start);
it->coord = it_next->coord;
it->content = it->content.substr(len);
it_next->content = it_next->content.substr(0,start) + it_next->content.substr(start + len);
}
else
{
if (next_end.line == coord.line)
{
coord.line = next_coord.line;
coord.column = next_coord.column + coord.column - next_end.column;
}
else
coord.line -= next_end.line - next_coord.line;
}
}
else if (it->type == Erase and next_end >= coord)
{
ByteCount start = count_byte_to(next_coord, coord, it_next->content);
it_next->content = it_next->content.substr(0, start) + it->content + it_next->content.substr(start);
it->coord = it_next->coord;
it->content.clear();
}
std::swap(*it, *it_next);
progress = true;
}
if (it->type == Erase and it_next->type == Erase and coord == next_coord)
{
it->content += it_next->content;
it_next = undo_group.erase(it_next);
progress = true;
}
else if (it->type == Insert and it_next->type == Insert and
is_in_range(next_coord, coord, advance(coord, it->content)))
{
ByteCount prefix_len = count_byte_to(coord, next_coord, it->content);
it->content = it->content.substr(0, prefix_len) + it_next->content
+ it->content.substr(prefix_len);
it_next = undo_group.erase(it_next);
progress = true;
}
else if (it->type == Insert and it_next->type == Erase and
coord <= next_coord and next_coord < advance(coord, it->content))
{
ByteCount insert_len = it->content.length();
ByteCount erase_len = it_next->content.length();
ByteCount prefix_len = count_byte_to(coord, next_coord, it->content);
it->content = it->content.substr(0, prefix_len) +
((prefix_len + erase_len < insert_len) ?
it->content.substr(prefix_len + erase_len) : "");
it_next->content = (insert_len - prefix_len < erase_len) ?
it_next->content.substr(insert_len - prefix_len) : "";
++it, ++it_next;
progress = true;
}
else if (it->type == Erase and it_next->type == Insert and coord == next_coord and
(pos = overlaps(it->content, it_next->content)) != -1)
{
ByteCount overlaps_len = it->content.length() - pos;
it->content = it->content.substr(0, pos);
it_next->coord = advance(it_next->coord, it_next->content.substr(0, overlaps_len));
it_next->content = it_next->content.substr(overlaps_len);
++it, ++it_next;
progress = true;
}
else
++it, ++it_next;
}
return progress;
}
static bool erase_empty(Buffer::UndoGroup& undo_group)
{
auto it = std::remove_if(begin(undo_group), end(undo_group),
[](Buffer::Modification& m) { return m.content.empty(); });
if (it != end(undo_group))
{
undo_group.erase(it, end(undo_group));
return true;
}
return false;
}
public:
static void optimize(Buffer::UndoGroup& undo_group)
{
while (undo_group.size() > 1)
{
bool progress = false;
progress |= merge_contiguous(undo_group);
progress |= erase_empty(undo_group);
if (not progress)
break;
}
}
};
void Buffer::commit_undo_group()
{
if (m_flags & Flags::NoUndo)
return;
UndoGroupOptimizer::optimize(m_current_undo_group);
if (m_current_undo_group.empty())
return;
m_history.erase(m_history_cursor, m_history.end());
m_history.push_back(std::move(m_current_undo_group));
m_current_undo_group.clear();
m_history_cursor = m_history.end();
if (m_history.size() < m_last_save_undo_index)
m_last_save_undo_index = -1;
}
bool Buffer::undo()
{
commit_undo_group();
if (m_history_cursor == m_history.begin())
return false;
--m_history_cursor;
for (const Modification& modification : reversed(*m_history_cursor))
apply_modification(modification.inverse());
return true;
}
bool Buffer::redo()
{
if (m_history_cursor == m_history.end())
return false;
kak_assert(m_current_undo_group.empty());
for (const Modification& modification : *m_history_cursor)
apply_modification(modification);
++m_history_cursor;
return true;
}
void Buffer::check_invariant() const
{
#ifdef KAK_DEBUG
ByteCount start = 0;
kak_assert(not m_lines.empty());
for (auto& line : m_lines)
{
kak_assert(line.start == start);
kak_assert(line.length() > 0);
kak_assert(line.content.back() == '\n');
start += line.length();
}
#endif
}
void Buffer::do_insert(const BufferIterator& pos, const String& content)
{
kak_assert(pos.is_valid());
if (content.empty())
return;
++m_timestamp;
ByteCount offset = pos.offset();
// all following lines advanced by length
for (LineCount i = pos.line()+1; i < line_count(); ++i)
m_lines[i].start += content.length();
BufferIterator begin_it;
BufferIterator end_it;
// if we inserted at the end of the buffer, we have created a new
// line without inserting a '\n'
if (pos.is_end())
{
ByteCount start = 0;
for (ByteCount i = 0; i < content.length(); ++i)
{
if (content[i] == '\n')
{
m_lines.push_back({ offset + start, content.substr(start, i + 1 - start) });
start = i + 1;
}
}
if (start != content.length())
m_lines.push_back({ offset + start, content.substr(start) });
begin_it = pos.column() == 0 ? pos : BufferIterator{*this, { pos.line() + 1, 0 }};
end_it = end();
}
else
{
String prefix = m_lines[pos.line()].content.substr(0, pos.column());
String suffix = m_lines[pos.line()].content.substr(pos.column());
std::vector<Line> new_lines;
ByteCount start = 0;
for (ByteCount i = 0; i < content.length(); ++i)
{
if (content[i] == '\n')
{
String line_content = content.substr(start, i + 1 - start);
if (start == 0)
{
line_content = prefix + line_content;
new_lines.push_back({ offset + start - prefix.length(),
std::move(line_content) });
}
else
new_lines.push_back({ offset + start, std::move(line_content) });
start = i + 1;
}
}
if (start == 0)
new_lines.push_back({ offset + start - prefix.length(), prefix + content + suffix });
else if (start != content.length() or not suffix.empty())
new_lines.push_back({ offset + start, content.substr(start) + suffix });
LineCount last_line = pos.line() + new_lines.size() - 1;
auto line_it = m_lines.begin() + (int)pos.line();
*line_it = std::move(*new_lines.begin());
m_lines.insert(line_it+1, std::make_move_iterator(new_lines.begin() + 1),
std::make_move_iterator(new_lines.end()));
begin_it = pos;
end_it = BufferIterator{*this, { last_line, m_lines[last_line].length() - suffix.length() }};
}
for (auto listener : m_change_listeners)
listener->on_insert(begin_it, end_it);
}
void Buffer::do_erase(const BufferIterator& begin, const BufferIterator& end)
{
kak_assert(begin.is_valid());
kak_assert(end.is_valid());
++m_timestamp;
const ByteCount length = end - begin;
String prefix = m_lines[begin.line()].content.substr(0, begin.column());
String suffix = m_lines[end.line()].content.substr(end.column());
Line new_line = { m_lines[begin.line()].start, prefix + suffix };
if (new_line.length() != 0)
{
m_lines.erase(m_lines.begin() + (int)begin.line(), m_lines.begin() + (int)end.line());
m_lines[begin.line()] = std::move(new_line);
}
else
m_lines.erase(m_lines.begin() + (int)begin.line(), m_lines.begin() + (int)end.line() + 1);
for (LineCount i = begin.line()+1; i < line_count(); ++i)
m_lines[i].start -= length;
for (auto listener : m_change_listeners)
listener->on_erase(begin, end);
}
void Buffer::apply_modification(const Modification& modification)
{
const String& content = modification.content;
BufferCoord coord = modification.coord;
// this may happen when a modification applied at the
// end of the buffer has been inverted for an undo.
if (coord.line < line_count()-1 and coord.column == m_lines[coord.line].length())
coord = { coord.line + 1, 0 };
BufferIterator pos{*this, coord};
switch (modification.type)
{
case Modification::Insert:
{
do_insert(pos, content);
break;
}
case Modification::Erase:
{
ByteCount count = content.length();
BufferIterator end = pos + count;
kak_assert(string(pos, end) == content);
do_erase(pos, end);
break;
}
default:
kak_assert(false);
}
}
void Buffer::insert(BufferIterator pos, String content)
{
if (content.empty())
return;
if (pos.is_end() and content.back() != '\n')
content += '\n';
if (not (m_flags & Flags::NoUndo))
m_current_undo_group.emplace_back(Modification::Insert, pos.coord(), content);
do_insert(pos, content);
}
void Buffer::erase(BufferIterator begin, BufferIterator end)
{
if (end.is_end() and (begin.column() != 0 or begin.is_begin()))
--end;
if (begin == end)
return;
if (not (m_flags & Flags::NoUndo))
m_current_undo_group.emplace_back(Modification::Erase, begin.coord(),
string(begin, end));
do_erase(begin, end);
}
bool Buffer::is_modified() const
{
size_t history_cursor_index = m_history_cursor - m_history.begin();
return m_last_save_undo_index != history_cursor_index
or not m_current_undo_group.empty();
}
void Buffer::notify_saved()
{
if (not m_current_undo_group.empty())
commit_undo_group();
m_flags &= ~Flags::New;
size_t history_cursor_index = m_history_cursor - m_history.begin();
if (m_last_save_undo_index != history_cursor_index)
{
++m_timestamp;
m_last_save_undo_index = history_cursor_index;
}
}
bool Buffer::is_valid(const BufferCoord& c) const
{
return (c.line < line_count() and c.column < m_lines[c.line].length()) or
(c.line == line_count() - 1 and c.column == m_lines.back().length()) or
(c.line == line_count() and c.column == 0);
}
}