kakoune/src/input_handler.cc
Maxime Coste e4fb70ebec Replace ModeChange hooks by ModePush and ModePop
Remove deprecated InsertBegin, InsertEnd, NormalBegin, NormalEnd
hooks.

Closes #2545
2019-10-16 20:45:53 +11:00

1760 lines
60 KiB
C++

#include <utility>
#include "input_handler.hh"
#include "buffer_manager.hh"
#include "buffer_utils.hh"
#include "command_manager.hh"
#include "client.hh"
#include "event_manager.hh"
#include "face_registry.hh"
#include "insert_completer.hh"
#include "normal.hh"
#include "option_types.hh"
#include "regex.hh"
#include "register_manager.hh"
#include "hash_map.hh"
#include "user_interface.hh"
#include "utf8.hh"
#include "window.hh"
namespace Kakoune
{
class InputMode : public RefCountable
{
public:
InputMode(InputHandler& input_handler) : m_input_handler(input_handler) {}
~InputMode() override = default;
InputMode(const InputMode&) = delete;
InputMode& operator=(const InputMode&) = delete;
void handle_key(Key key) { RefPtr<InputMode> keep_alive{this}; on_key(key); }
virtual void on_enabled() {}
virtual void on_disabled(bool temporary) {}
bool enabled() const { return &m_input_handler.current_mode() == this; }
Context& context() const { return m_input_handler.context(); }
virtual DisplayLine mode_line() const = 0;
virtual KeymapMode keymap_mode() const = 0;
virtual StringView name() const = 0;
virtual std::pair<CursorMode, DisplayCoord> get_cursor_info() const
{
const auto cursor = context().selections().main().cursor();
auto coord = context().window().display_position(cursor).value_or(DisplayCoord{});
return {CursorMode::Buffer, coord};
}
using Insertion = InputHandler::Insertion;
Insertion& last_insert() { return m_input_handler.m_last_insert; }
protected:
virtual void on_key(Key key) = 0;
void push_mode(InputMode* new_mode)
{
m_input_handler.push_mode(new_mode);
}
void pop_mode()
{
m_input_handler.pop_mode(this);
}
private:
InputHandler& m_input_handler;
};
namespace InputModes
{
std::chrono::milliseconds get_idle_timeout(const Context& context)
{
return std::chrono::milliseconds{context.options()["idle_timeout"].get<int>()};
}
std::chrono::milliseconds get_fs_check_timeout(const Context& context)
{
return std::chrono::milliseconds{context.options()["fs_check_timeout"].get<int>()};
}
struct MouseHandler
{
bool handle_key(Key key, Context& context)
{
if (not context.has_window())
return false;
Buffer& buffer = context.buffer();
BufferCoord cursor;
auto& selections = context.selections();
constexpr auto modifiers = Key::Modifiers::Control | Key::Modifiers::Alt | Key::Modifiers::Shift;
switch ((key.modifiers & ~modifiers).value)
{
case Key::Modifiers::MousePressRight:
m_dragging = false;
cursor = context.window().buffer_coord(key.coord());
if (key.modifiers & Key::Modifiers::Control)
selections = {{selections.begin()->anchor(), cursor}};
else
selections.main() = {selections.main().anchor(), cursor};
selections.sort_and_merge_overlapping();
return true;
case Key::Modifiers::MousePressLeft:
m_dragging = true;
m_anchor = context.window().buffer_coord(key.coord());
if (not (key.modifiers & Key::Modifiers::Control))
context.selections_write_only() = { buffer, m_anchor};
else
{
size_t main = selections.size();
selections.push_back({m_anchor});
selections.set_main_index(main);
selections.sort_and_merge_overlapping();
}
return true;
case Key::Modifiers::MouseReleaseLeft:
case Key::Modifiers::MouseReleaseRight:
if (not m_dragging)
return true;
m_dragging = false;
cursor = context.window().buffer_coord(key.coord());
selections.main() = {buffer.clamp(m_anchor), cursor};
selections.sort_and_merge_overlapping();
return true;
case Key::Modifiers::MousePos:
if (not m_dragging)
return true;
cursor = context.window().buffer_coord(key.coord());
selections.main() = {buffer.clamp(m_anchor), cursor};
selections.sort_and_merge_overlapping();
return true;
case Key::Modifiers::Scroll:
scroll_window(context, static_cast<int32_t>(key.key), not m_dragging);
return true;
default: return false;
}
}
private:
bool m_dragging = false;
BufferCoord m_anchor;
};
constexpr StringView register_doc =
"Special registers:\n"
"[0-9]: selections capture group\n"
"%: buffer name\n"
".: selection contents\n"
"#: selection index\n"
"_: null register\n"
"\": default yank/paste register\n"
"@: default macro register\n"
"/: default search register\n"
"^: default mark register\n"
"|: default shell command register\n"
":: last entered command\n";
class Normal : public InputMode
{
public:
Normal(InputHandler& input_handler, bool single_command = false)
: InputMode(input_handler),
m_idle_timer{TimePoint::max(),
context().flags() & Context::Flags::Draft ?
Timer::Callback{} : [this](Timer&) {
context().hooks().run_hook(Hook::NormalIdle, "", context());
}},
m_fs_check_timer{TimePoint::max(),
context().flags() & Context::Flags::Draft ?
Timer::Callback{} : Timer::Callback{[this](Timer& timer) {
if (context().has_client())
context().client().check_if_buffer_needs_reloading();
timer.set_next_date(Clock::now() + get_fs_check_timeout(context()));
}}},
m_state(single_command ? State::SingleCommand : State::Normal)
{}
void on_enabled() override
{
if (m_state == State::PopOnEnabled)
return pop_mode();
if (not (context().flags() & Context::Flags::Draft))
{
if (context().has_client())
context().client().check_if_buffer_needs_reloading();
m_fs_check_timer.set_next_date(Clock::now() + get_fs_check_timeout(context()));
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
if (m_hooks_disabled and not m_in_on_key)
{
context().hooks_disabled().unset();
m_hooks_disabled = false;
}
}
void on_disabled(bool temporary) override
{
m_idle_timer.set_next_date(TimePoint::max());
m_fs_check_timer.set_next_date(TimePoint::max());
if (not temporary and m_hooks_disabled)
{
context().hooks_disabled().unset();
m_hooks_disabled = false;
}
}
void on_key(Key key) override
{
kak_assert(m_state != State::PopOnEnabled);
ScopedSetBool set_in_on_key{m_in_on_key};
bool do_restore_hooks = false;
auto restore_hooks = on_scope_end([&, this]{
if (m_hooks_disabled and enabled() and do_restore_hooks)
{
context().hooks_disabled().unset();
m_hooks_disabled = false;
}
});
const bool transient = context().flags() & Context::Flags::Draft;
if (m_mouse_handler.handle_key(key, context()))
{
context().print_status({});
if (context().has_client())
context().client().info_hide();
if (not transient)
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
else if (auto cp = key.codepoint(); cp and isdigit(*cp))
{
long long new_val = (long long)m_params.count * 10 + *cp - '0';
if (new_val > std::numeric_limits<int>::max())
context().print_status({ "parameter overflowed", context().faces()["Error"] });
else
m_params.count = new_val;
}
else if (key == Key::Backspace)
m_params.count /= 10;
else if (key == '\\')
{
if (not m_hooks_disabled)
{
m_hooks_disabled = true;
context().hooks_disabled().set();
}
}
else if (key == '"')
{
on_next_key_with_autoinfo(context(), KeymapMode::None,
[this](Key key, Context& context) {
auto cp = key.codepoint();
if (not cp or key == Key::Escape)
return;
if (*cp <= 127)
m_params.reg = *cp;
else
context.print_status(
{ format("invalid register '{}'", *cp),
context.faces()["Error"] });
}, "enter target register", register_doc);
}
else
{
auto pop_if_single_command = on_scope_end([this] {
if (m_state == State::SingleCommand and enabled())
pop_mode();
else if (m_state == State::SingleCommand)
m_state = State::PopOnEnabled;
});
context().print_status({});
if (context().has_client())
context().client().info_hide();
// Hack to parse keys sent by terminals using the 8th bit to mark the
// meta key. In normal mode, give priority to a potential alt-key than
// the accentuated character.
if (key.key >= 127 and key.key < 256)
{
key.modifiers |= Key::Modifiers::Alt;
key.key &= 0x7f;
}
do_restore_hooks = true;
if (auto command = get_normal_command(key))
{
auto autoinfo = context().options()["autoinfo"].get<AutoInfo>();
if (autoinfo & AutoInfo::Normal and context().has_client())
context().client().info_show(key_to_str(key), command->docstring.str(),
{}, InfoStyle::Prompt);
// reset m_params now to be reentrant
NormalParams params = m_params;
m_params = { 0, 0 };
command->func(context(), params);
}
}
context().hooks().run_hook(Hook::NormalKey, key_to_str(key), context());
if (enabled() and not transient) // The hook might have changed mode
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
DisplayLine mode_line() const override
{
AtomList atoms;
auto num_sel = context().selections().size();
auto main_index = context().selections().main_index();
if (num_sel == 1)
atoms.emplace_back(format("{} sel", num_sel), context().faces()["StatusLineInfo"]);
else
atoms.emplace_back(format("{} sels ({})", num_sel, main_index + 1), context().faces()["StatusLineInfo"]);
if (m_params.count != 0)
{
atoms.emplace_back(" param=", context().faces()["StatusLineInfo"]);
atoms.emplace_back(to_string(m_params.count), context().faces()["StatusLineValue"]);
}
if (m_params.reg)
{
atoms.emplace_back(" reg=", context().faces()["StatusLineInfo"]);
atoms.emplace_back(StringView(m_params.reg).str(), context().faces()["StatusLineValue"]);
}
return atoms;
}
KeymapMode keymap_mode() const override { return KeymapMode::Normal; }
StringView name() const override { return "normal"; }
private:
friend struct InputHandler::ScopedForceNormal;
NormalParams m_params = { 0, 0 };
bool m_hooks_disabled = false;
NestedBool m_in_on_key;
Timer m_idle_timer;
Timer m_fs_check_timer;
MouseHandler m_mouse_handler;
enum class State { Normal, SingleCommand, PopOnEnabled };
State m_state;
};
template<WordType word_type>
void to_next_word_begin(CharCount& pos, StringView line)
{
const CharCount len = line.char_length();
if (pos == len)
return;
if (word_type == Word and is_punctuation(line[pos]))
{
while (pos != len and is_punctuation(line[pos]))
++pos;
}
else if (is_word<word_type>(line[pos]))
{
while (pos != len and is_word<word_type>(line[pos]))
++pos;
}
while (pos != len and is_horizontal_blank(line[pos]))
++pos;
}
template<WordType word_type>
void to_next_word_end(CharCount& pos, StringView line)
{
const CharCount len = line.char_length();
if (pos + 1 >= len)
return;
++pos;
while (pos != len and is_horizontal_blank(line[pos]))
++pos;
if (word_type == Word and is_punctuation(line[pos]))
{
while (pos != len and is_punctuation(line[pos]))
++pos;
}
else if (is_word<word_type>(line[pos]))
{
while (pos != len and is_word<word_type>(line[pos]))
++pos;
}
--pos;
}
template<WordType word_type>
void to_prev_word_begin(CharCount& pos, StringView line)
{
if (pos == 0_char)
return;
--pos;
while (pos != 0_char and is_horizontal_blank(line[pos]))
--pos;
if (word_type == Word and is_punctuation(line[pos]))
{
while (pos != 0_char and is_punctuation(line[pos]))
--pos;
if (!is_punctuation(line[pos]))
++pos;
}
else if (is_word<word_type>(line[pos]))
{
while (pos != 0_char and is_word<word_type>(line[pos]))
--pos;
if (!is_word<word_type>(line[pos]))
++pos;
}
}
class LineEditor
{
public:
LineEditor(const FaceRegistry& faces) : m_faces{faces} {}
void handle_key(Key key)
{
auto erase_move = [this](auto&& move_func) {
auto old_pos = m_cursor_pos;
move_func(m_cursor_pos, m_line);
if (m_cursor_pos > old_pos)
std::swap(m_cursor_pos, old_pos);
m_clipboard = m_line.substr(m_cursor_pos, old_pos - m_cursor_pos).str();
m_line = m_line.substr(0, m_cursor_pos) + m_line.substr(old_pos);
};
if (key == Key::Left or key == ctrl('b'))
{
if (m_cursor_pos > 0)
--m_cursor_pos;
}
else if (key == Key::Right or key == ctrl('f'))
{
if (m_cursor_pos < m_line.char_length())
++m_cursor_pos;
}
else if (key == Key::Home or key == ctrl('a'))
m_cursor_pos = 0;
else if (key == Key::End or key == ctrl('e'))
m_cursor_pos = m_line.char_length();
else if (key == Key::Backspace or key == ctrl('h'))
{
if (m_cursor_pos != 0)
{
m_line = m_line.substr(0_char, m_cursor_pos - 1)
+ m_line.substr(m_cursor_pos);
--m_cursor_pos;
}
}
else if (key == Key::Delete or key == ctrl('d'))
{
if (m_cursor_pos != m_line.char_length())
m_line = m_line.substr(0, m_cursor_pos)
+ m_line.substr(m_cursor_pos+1);
}
else if (key == alt('f'))
to_next_word_begin<Word>(m_cursor_pos, m_line);
else if (key == alt('F'))
to_next_word_begin<WORD>(m_cursor_pos, m_line);
else if (key == alt('b'))
to_prev_word_begin<Word>(m_cursor_pos, m_line);
else if (key == alt('B'))
to_prev_word_begin<WORD>(m_cursor_pos, m_line);
else if (key == alt('e'))
to_next_word_end<Word>(m_cursor_pos, m_line);
else if (key == alt('E'))
to_next_word_end<WORD>(m_cursor_pos, m_line);
else if (key == ctrl('k'))
{
m_clipboard = m_line.substr(m_cursor_pos).str();
m_line = m_line.substr(0, m_cursor_pos).str();
}
else if (key == ctrl('u'))
{
m_clipboard = m_line.substr(0, m_cursor_pos).str();
m_line = m_line.substr(m_cursor_pos).str();
m_cursor_pos = 0;
}
else if (key == ctrl('w') or key == alt(Key::Backspace))
erase_move(&to_prev_word_begin<Word>);
else if (key == ctrl('W'))
erase_move(&to_prev_word_begin<WORD>);
else if (key == alt('d'))
erase_move(&to_next_word_begin<Word>);
else if (key == alt('D'))
erase_move(&to_next_word_begin<WORD>);
else if (key == ctrl('y'))
{
m_line = m_line.substr(0, m_cursor_pos) + m_clipboard + m_line.substr(m_cursor_pos);
m_cursor_pos += m_clipboard.char_length();
}
else if (auto cp = key.codepoint())
insert(*cp);
}
void insert(Codepoint cp)
{
m_line = m_line.substr(0, m_cursor_pos) + String{cp}
+ m_line.substr(m_cursor_pos);
++m_cursor_pos;
}
void insert(StringView str)
{
insert_from(m_cursor_pos, str);
}
void insert_from(CharCount start, StringView str)
{
kak_assert(start <= m_cursor_pos);
m_line = m_line.substr(0, start) + str
+ m_line.substr(m_cursor_pos);
m_cursor_pos = start + str.char_length();
}
void reset(String line, StringView empty_text)
{
m_line = std::move(line);
m_empty_text = empty_text;
m_cursor_pos = m_line.char_length();
m_display_pos = 0;
}
const String& line() const { return m_line; }
CharCount cursor_pos() const { return m_cursor_pos; }
ColumnCount cursor_display_column() const
{
return m_line.substr(m_display_pos, m_cursor_pos).column_length();
}
DisplayLine build_display_line(ColumnCount in_width)
{
CharCount width = (int)in_width; // Todo: proper handling of char/column
kak_assert(m_cursor_pos <= m_line.char_length());
if (m_cursor_pos < m_display_pos)
m_display_pos = m_cursor_pos;
if (m_cursor_pos >= m_display_pos + width)
m_display_pos = m_cursor_pos + 1 - width;
const bool empty = m_line.empty();
StringView str = empty ? m_empty_text : m_line;
const Face line_face = m_faces[empty ? "StatusLineInfo" : "StatusLine"];
const Face cursor_face = m_faces["StatusCursor"];
if (m_cursor_pos == str.char_length())
return DisplayLine{{ { fix_atom_text(str.substr(m_display_pos, width-1)), line_face },
{ " "_str, cursor_face} } };
else
return DisplayLine({ { fix_atom_text(str.substr(m_display_pos, m_cursor_pos - m_display_pos)), line_face },
{ fix_atom_text(str.substr(m_cursor_pos,1)), cursor_face },
{ fix_atom_text(str.substr(m_cursor_pos+1, width - m_cursor_pos + m_display_pos - 1)), line_face } });
}
private:
CharCount m_cursor_pos = 0;
CharCount m_display_pos = 0;
String m_line;
StringView m_empty_text = {};
String m_clipboard;
const FaceRegistry& m_faces;
};
class Menu : public InputMode
{
public:
Menu(InputHandler& input_handler, Vector<DisplayLine> choices,
MenuCallback callback)
: InputMode(input_handler),
m_callback(std::move(callback)), m_choices(choices.begin(), choices.end()),
m_selected(m_choices.begin()),
m_filter_editor{context().faces()}
{
if (not context().has_client())
return;
context().client().menu_show(std::move(choices), {}, MenuStyle::Prompt);
context().client().menu_select(0);
}
void on_key(Key key) override
{
auto match_filter = [this](const DisplayLine& choice) {
for (auto& atom : choice)
{
const auto& contents = atom.content();
if (regex_match(contents.begin(), contents.end(), m_filter))
return true;
}
return false;
};
if (key == Key::Return)
{
if (context().has_client())
context().client().menu_hide();
context().print_status(DisplayLine{});
// Maintain hooks disabled in callback if they were before pop_mode
ScopedSetBool disable_hooks(context().hooks_disabled(),
context().hooks_disabled());
pop_mode();
int selected = m_selected - m_choices.begin();
m_callback(selected, MenuEvent::Validate, context());
return;
}
else if (key == Key::Escape or key == ctrl('c'))
{
if (m_edit_filter)
{
m_edit_filter = false;
m_filter = Regex{".*"};
m_filter_editor.reset("", "");
context().print_status(DisplayLine{});
}
else
{
if (context().has_client())
context().client().menu_hide();
// Maintain hooks disabled in callback if they were before pop_mode
ScopedSetBool disable_hooks(context().hooks_disabled(),
context().hooks_disabled());
pop_mode();
int selected = m_selected - m_choices.begin();
m_callback(selected, MenuEvent::Abort, context());
}
}
else if (key == Key::Down or key == Key::Tab or
key == ctrl('n') or (not m_edit_filter and key == 'j'))
{
auto it = std::find_if(m_selected+1, m_choices.end(), match_filter);
if (it == m_choices.end())
it = std::find_if(m_choices.begin(), m_selected, match_filter);
select(it);
}
else if (key == Key::Up or key == shift(Key::Tab) or
key == ctrl('p') or (not m_edit_filter and key == 'k'))
{
ChoiceList::const_reverse_iterator selected(m_selected+1);
auto it = std::find_if(selected+1, m_choices.rend(), match_filter);
if (it == m_choices.rend())
it = std::find_if(m_choices.rbegin(), selected, match_filter);
select(it.base()-1);
}
else if (key == '/' and not m_edit_filter)
{
m_edit_filter = true;
}
else if (m_edit_filter)
{
m_filter_editor.handle_key(key);
auto search = ".*" + m_filter_editor.line() + ".*";
m_filter = Regex{search};
auto it = std::find_if(m_selected, m_choices.end(), match_filter);
if (it == m_choices.end())
it = std::find_if(m_choices.begin(), m_selected, match_filter);
select(it);
}
if (m_edit_filter and context().has_client())
{
auto prompt = "filter:"_str;
auto width = context().client().dimensions().column - prompt.column_length();
auto display_line = m_filter_editor.build_display_line(width);
display_line.insert(display_line.begin(), { prompt, context().faces()["Prompt"] });
context().print_status(display_line);
}
}
DisplayLine mode_line() const override
{
return { "menu", context().faces()["StatusLineMode"] };
}
KeymapMode keymap_mode() const override { return KeymapMode::Menu; }
StringView name() const override { return "menu"; }
private:
MenuCallback m_callback;
using ChoiceList = Vector<DisplayLine>;
const ChoiceList m_choices;
ChoiceList::const_iterator m_selected;
void select(ChoiceList::const_iterator it)
{
m_selected = it;
int selected = m_selected - m_choices.begin();
if (context().has_client())
context().client().menu_select(selected);
m_callback(selected, MenuEvent::Select, context());
}
Regex m_filter = Regex{".*"};
bool m_edit_filter = false;
LineEditor m_filter_editor;
};
static Optional<Codepoint> get_raw_codepoint(Key key)
{
if (auto cp = key.codepoint())
return cp;
else if (key.modifiers == Key::Modifiers::Control and
((key.key >= '@' and key.key <= '_') or
(key.key >= 'a' and key.key <= 'z')))
return {(Codepoint)(to_upper((char)key.key) - '@')};
return {};
}
class Prompt : public InputMode
{
public:
Prompt(InputHandler& input_handler, StringView prompt,
String initstr, String emptystr, Face face, PromptFlags flags,
char history_register, PromptCompleter completer, PromptCallback callback)
: InputMode(input_handler), m_callback(std::move(callback)), m_completer(std::move(completer)),
m_prompt(prompt.str()), m_prompt_face(face),
m_empty_text{std::move(emptystr)},
m_line_editor{context().faces()}, m_flags(flags),
m_history{RegisterManager::instance()[history_register]},
m_current_history{m_history.get(context()).size()},
m_auto_complete{context().options()["autocomplete"].get<AutoComplete>() & AutoComplete::Prompt},
m_idle_timer{TimePoint::max(), context().flags() & Context::Flags::Draft ?
Timer::Callback{} : [this](Timer&) {
if (m_auto_complete and m_refresh_completion_pending)
refresh_completions(CompletionFlags::Fast);
if (m_line_changed)
{
m_callback(m_line_editor.line(), PromptEvent::Change, context());
m_line_changed = false;
}
context().hooks().run_hook(Hook::PromptIdle, "", context());
}}
{
m_line_editor.reset(std::move(initstr), m_empty_text);
}
void on_key(Key key) override
{
const String& line = m_line_editor.line();
if (key == Key::Return)
{
if ((m_completions.flags & Completions::Flags::Menu) and
m_current_completion == -1 and
not m_completions.candidates.empty())
{
const String& completion = m_completions.candidates.front();
m_line_editor.insert_from(line.char_count_to(m_completions.start),
completion);
}
history_push(line);
context().print_status(DisplayLine{});
if (context().has_client())
context().client().menu_hide();
// Maintain hooks disabled in callback if they were before pop_mode
ScopedSetBool disable_hooks(context().hooks_disabled(),
context().hooks_disabled());
pop_mode();
// call callback after pop_mode so that callback
// may change the mode
m_callback(line, PromptEvent::Validate, context());
return;
}
else if (key == Key::Escape or key == ctrl('c'))
{
history_push(line);
context().print_status(DisplayLine{});
if (context().has_client())
context().client().menu_hide();
// Maintain hooks disabled in callback if they were before pop_mode
ScopedSetBool disable_hooks(context().hooks_disabled(),
context().hooks_disabled());
pop_mode();
m_callback(line, PromptEvent::Abort, context());
return;
}
else if (key == ctrl('r'))
{
on_next_key_with_autoinfo(context(), KeymapMode::None,
[this](Key key, Context&) {
auto cp = key.codepoint();
if (not cp or key == Key::Escape)
return;
StringView reg = context().main_sel_register_value(String{*cp});
m_line_editor.insert(reg);
display();
m_line_changed = true;
m_refresh_completion_pending = true;
}, "enter register name", register_doc);
display();
return;
}
else if (key == ctrl('v'))
{
on_next_key_with_autoinfo(context(), KeymapMode::None,
[this](Key key, Context&) {
if (auto cp = get_raw_codepoint(key))
{
m_line_editor.insert(*cp);
display();
m_line_changed = true;
m_refresh_completion_pending = true;
}
}, "raw insert", "enter key to insert");
display();
return;
}
else if (key == Key::Up or key == ctrl('p'))
{
if (m_current_history != 0)
{
auto history = m_history.get(context());
// The history register might have been mutated in the mean time
m_current_history = std::min(history.size(), m_current_history);
if (m_current_history == history.size())
m_prefix = line;
auto index = m_current_history;
// search for the previous history entry matching typed prefix
do
{
--index;
if (prefix_match(history[index], m_prefix))
{
m_current_history = index;
m_line_editor.reset(history[index], m_empty_text);
break;
}
} while (index != 0);
clear_completions();
m_refresh_completion_pending = true;
}
}
else if (key == Key::Down or key == ctrl('n')) // next
{
auto history = m_history.get(context());
// The history register might have been mutated in the mean time
m_current_history = std::min(history.size(), m_current_history);
if (m_current_history < history.size())
{
// search for the next history entry matching typed prefix
++m_current_history;
while (m_current_history != history.size() and
not prefix_match(history[m_current_history], m_prefix))
++m_current_history;
if (m_current_history != history.size())
m_line_editor.reset(history[m_current_history], m_empty_text);
else
m_line_editor.reset(m_prefix, m_empty_text);
clear_completions();
m_refresh_completion_pending = true;
}
}
else if (key == Key::Tab or key == shift(Key::Tab) or key.modifiers == Key::Modifiers::MenuSelect) // completion
{
CandidateList& candidates = m_completions.candidates;
// first try, we need to ask our completer for completions
if (candidates.empty())
{
refresh_completions(CompletionFlags::None);
if ((not m_prefix_in_completions and candidates.size() > 1) or
candidates.size() > 2)
return;
}
if (candidates.empty())
return;
const bool reverse = (key == shift(Key::Tab));
if (key.modifiers == Key::Modifiers::MenuSelect)
m_current_completion = clamp<int>(key.key, 0, candidates.size() - 1);
else if (not reverse and ++m_current_completion >= candidates.size())
m_current_completion = 0;
else if (reverse and --m_current_completion < 0)
m_current_completion = candidates.size()-1;
const String& completion = candidates[m_current_completion];
if (context().has_client())
context().client().menu_select(m_current_completion);
m_line_editor.insert_from(line.char_count_to(m_completions.start),
completion);
// when we have only one completion candidate, make next tab complete
// from the new content.
if (candidates.size() == 1 or
(m_prefix_in_completions and candidates.size() == 2))
{
m_current_completion = -1;
candidates.clear();
m_refresh_completion_pending = true;
}
}
else if (key == ctrl('o'))
{
m_auto_complete = not m_auto_complete;
if (m_auto_complete)
refresh_completions(CompletionFlags::Fast);
else if (context().has_client())
{
clear_completions();
context().client().menu_hide();
}
}
else if (key == alt('!'))
{
try
{
m_line_editor.reset(expand(m_line_editor.line(), context()), m_empty_text);
}
catch (std::runtime_error& error)
{
context().print_status({error.what(), context().faces()["Error"]});
return;
}
}
else if (key == alt(';'))
{
push_mode(new Normal(context().input_handler(), true));
return;
}
else
{
m_line_editor.handle_key(key);
clear_completions();
m_refresh_completion_pending = true;
}
display();
m_line_changed = true;
if (enabled() and not (context().flags() & Context::Flags::Draft)) // The callback might have disabled us
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
void set_prompt_face(Face face)
{
if (face != m_prompt_face)
{
m_prompt_face = face;
display();
}
}
DisplayLine mode_line() const override
{
return { "prompt", context().faces()["StatusLineMode"] };
}
KeymapMode keymap_mode() const override { return KeymapMode::Prompt; }
StringView name() const override { return "prompt"; }
std::pair<CursorMode, DisplayCoord> get_cursor_info() const override
{
DisplayCoord coord{0_line, m_prompt.column_length() + m_line_editor.cursor_display_column()};
return { CursorMode::Prompt, coord };
}
private:
void refresh_completions(CompletionFlags flags)
{
try
{
m_refresh_completion_pending = false;
if (not m_completer)
return;
m_current_completion = -1;
const String& line = m_line_editor.line();
m_completions = m_completer(context(), flags, line,
line.byte_count_to(m_line_editor.cursor_pos()));
const bool menu = (bool)(m_completions.flags & Completions::Flags::Menu);
if (context().has_client())
{
if (m_completions.candidates.empty())
return context().client().menu_hide();
Vector<DisplayLine> items;
for (auto& candidate : m_completions.candidates)
items.push_back({ candidate, {} });
const auto menu_style = (m_flags & PromptFlags::Search) ? MenuStyle::Search : MenuStyle::Prompt;
context().client().menu_show(items, {}, menu_style);
if (menu)
context().client().menu_select(0);
auto prefix = line.substr(m_completions.start, m_completions.end - m_completions.start);
if (not menu and not contains(m_completions.candidates, prefix))
{
m_current_completion = m_completions.candidates.size();
m_completions.candidates.push_back(prefix.str());
m_prefix_in_completions = true;
}
else
m_prefix_in_completions = false;
}
} catch (runtime_error&) {}
}
void clear_completions()
{
m_current_completion = -1;
m_completions.candidates.clear();
}
void display()
{
if (not context().has_client())
return;
auto width = context().client().dimensions().column - m_prompt.column_length();
DisplayLine display_line;
if (not (m_flags & PromptFlags::Password))
display_line = m_line_editor.build_display_line(width);
display_line.insert(display_line.begin(), { m_prompt, m_prompt_face });
context().print_status(display_line);
}
void on_enabled() override
{
display();
m_line_changed = true;
if (not (context().flags() & Context::Flags::Draft))
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
void on_disabled(bool temporary) override
{
if (not temporary)
context().print_status({});
m_idle_timer.set_next_date(TimePoint::max());
if (context().has_client())
context().client().menu_hide();
}
PromptCallback m_callback;
PromptCompleter m_completer;
const String m_prompt;
Face m_prompt_face;
Completions m_completions;
int m_current_completion = -1;
bool m_prefix_in_completions = false;
String m_prefix;
String m_empty_text;
LineEditor m_line_editor;
bool m_line_changed = false;
PromptFlags m_flags;
Register& m_history;
size_t m_current_history;
bool m_auto_complete;
bool m_refresh_completion_pending = true;
Timer m_idle_timer;
void history_push(StringView entry)
{
if (entry.empty() or context().history_disabled() or
(m_flags & PromptFlags::DropHistoryEntriesWithBlankPrefix and
is_horizontal_blank(entry[0_byte])))
return;
m_history.set(context(), {entry.str()});
}
};
class NextKey : public InputMode
{
public:
NextKey(InputHandler& input_handler, KeymapMode keymap_mode, KeyCallback callback)
: InputMode(input_handler), m_callback(std::move(callback)), m_keymap_mode(keymap_mode) {}
void on_key(Key key) override
{
// maintain hooks disabled in the callback if they were before pop_mode
ScopedSetBool disable_hooks(context().hooks_disabled(),
context().hooks_disabled());
pop_mode();
m_callback(key, context());
}
DisplayLine mode_line() const override
{
return { "enter key", context().faces()["StatusLineMode"] };
}
KeymapMode keymap_mode() const override { return m_keymap_mode; }
StringView name() const override { return "next-key"; }
private:
KeyCallback m_callback;
KeymapMode m_keymap_mode;
};
class Insert : public InputMode
{
public:
Insert(InputHandler& input_handler, InsertMode mode, int count)
: InputMode(input_handler),
m_edition(context()),
m_completer(context()),
m_restore_cursor(mode == InsertMode::Append),
m_auto_complete{context().options()["autocomplete"].get<AutoComplete>() & AutoComplete::Insert},
m_idle_timer{TimePoint::max(), context().flags() & Context::Flags::Draft ?
Timer::Callback{} : [this](Timer&) {
m_completer.update(m_auto_complete);
context().hooks().run_hook(Hook::InsertIdle, "", context());
}},
m_disable_hooks{context().hooks_disabled(), context().hooks_disabled()}
{
context().buffer().throw_if_read_only();
last_insert().recording.set();
last_insert().mode = mode;
last_insert().keys.clear();
last_insert().disable_hooks = context().hooks_disabled();
last_insert().count = count;
prepare(mode, count);
}
void on_enabled() override
{
if (not (context().flags() & Context::Flags::Draft))
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
void on_disabled(bool temporary) override
{
m_idle_timer.set_next_date(TimePoint::max());
if (not temporary)
{
last_insert().recording.unset();
auto& selections = context().selections();
if (m_restore_cursor)
{
for (auto& sel : selections)
{
if (sel.cursor() > sel.anchor() and sel.cursor() > BufferCoord{0, 0})
sel.cursor() = context().buffer().char_prev(sel.cursor());
}
}
}
}
void on_key(Key key) override
{
auto& buffer = context().buffer();
const bool transient = context().flags() & Context::Flags::Draft;
bool update_completions = true;
bool moved = false;
if (m_mouse_handler.handle_key(key, context()))
{
if (not transient)
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
else if (key == Key::Escape or key == ctrl('c'))
{
m_completer.reset();
pop_mode();
}
else if (key == Key::Backspace)
{
Vector<Selection> sels;
for (auto& sel : context().selections())
{
if (sel.cursor() == BufferCoord{0,0})
continue;
auto pos = sel.cursor();
sels.emplace_back(buffer.char_prev(pos));
}
auto& main = context().selections().main();
String main_char;
if (main.cursor() != BufferCoord{0, 0})
main_char = buffer.string(buffer.char_prev(main.cursor()),
main.cursor());
if (not sels.empty())
SelectionList{buffer, std::move(sels)}.erase();
if (not main_char.empty())
context().hooks().run_hook(Hook::InsertDelete, main_char, context());
context().selections_write_only().update(false);
}
else if (key == Key::Delete)
{
Vector<Selection> sels;
for (auto& sel : context().selections())
sels.emplace_back(sel.cursor());
SelectionList{buffer, std::move(sels)}.erase();
}
else if (key == Key::Left)
{
move(-1_char);
moved = true;
}
else if (key == Key::Right)
{
move(1_char);
moved = true;
}
else if (key == Key::Up)
{
move(-1_line);
moved = true;
}
else if (key == Key::Down)
{
move(1_line);
moved = true;
}
else if (key == Key::Home)
{
auto& selections = context().selections();
for (auto& sel : selections)
sel.anchor() = sel.cursor() = BufferCoord{sel.cursor().line, 0};
selections.sort_and_merge_overlapping();
}
else if (key == Key::End)
{
auto& buffer = context().buffer();
auto& selections = context().selections();
for (auto& sel : selections)
{
const LineCount line = sel.cursor().line;
sel.anchor() = sel.cursor() = buffer.clamp({line, buffer[line].length()});
}
selections.sort_and_merge_overlapping();
}
else if (auto cp = key.codepoint())
insert(*cp);
else if (key == ctrl('r'))
{
on_next_key_with_autoinfo(context(), KeymapMode::None,
[this](Key key, Context&) {
auto cp = key.codepoint();
if (not cp or key == Key::Escape)
return;
insert(RegisterManager::instance()[*cp].get(context()));
}, "enter register name", register_doc);
update_completions = false;
}
else if (key == ctrl('n'))
{
last_insert().keys.pop_back();
m_completer.select(1, true, last_insert().keys);
update_completions = false;
}
else if (key == ctrl('p'))
{
last_insert().keys.pop_back();
m_completer.select(-1, true, last_insert().keys);
update_completions = false;
}
else if (key.modifiers == Key::Modifiers::MenuSelect)
{
last_insert().keys.pop_back();
m_completer.select(key.key, false, last_insert().keys);
update_completions = false;
}
else if (key == ctrl('x'))
{
on_next_key_with_autoinfo(context(), KeymapMode::None,
[this](Key key, Context&) {
if (key.key == 'f')
m_completer.explicit_file_complete();
if (key.key == 'w')
m_completer.explicit_word_buffer_complete();
if (key.key == 'W')
m_completer.explicit_word_all_complete();
if (key.key == 'l')
m_completer.explicit_line_buffer_complete();
if (key.key == 'L')
m_completer.explicit_line_all_complete();
}, "enter completion type",
"f: filename\n"
"w: word (current buffer)\n"
"W: word (all buffers)\n"
"l: line (current buffer)\n"
"L: line (all buffers)\n");
update_completions = false;
}
else if (key == ctrl('o'))
{
m_auto_complete = not m_auto_complete;
m_completer.reset();
}
else if (key == ctrl('u'))
{
context().buffer().commit_undo_group();
context().print_status({ format("committed change #{}",
(size_t)context().buffer().current_history_id()),
context().faces()["Information"] });
}
else if (key == ctrl('v'))
{
on_next_key_with_autoinfo(context(), KeymapMode::None,
[this, transient](Key key, Context&) {
if (auto cp = get_raw_codepoint(key))
{
insert(*cp);
context().hooks().run_hook(Hook::InsertKey, key_to_str(key), context());
if (enabled() and not transient)
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
}, "raw insert", "enter key to insert");
update_completions = false;
}
else if (key == alt(';'))
{
push_mode(new Normal(context().input_handler(), true));
return;
}
context().hooks().run_hook(Hook::InsertKey, key_to_str(key), context());
if (moved)
context().hooks().run_hook(Hook::InsertMove, key_to_str(key), context());
if (update_completions and enabled() and not transient) // Hooks might have disabled us
m_idle_timer.set_next_date(Clock::now() + get_idle_timeout(context()));
}
DisplayLine mode_line() const override
{
auto num_sel = context().selections().size();
auto main_index = context().selections().main_index();
return {AtomList{ { "insert", context().faces()["StatusLineMode"] },
{ " ", context().faces()["StatusLine"] },
{ format( "{} sels ({})", num_sel, main_index + 1),
context().faces()["StatusLineInfo"] } }};
}
KeymapMode keymap_mode() const override { return KeymapMode::Insert; }
StringView name() const override { return "insert"; }
private:
template<typename Type>
void move(Type offset)
{
auto& selections = context().selections();
const ColumnCount tabstop = context().options()["tabstop"].get<int>();
for (auto& sel : selections)
{
auto cursor = context().buffer().offset_coord(sel.cursor(), offset, tabstop, false);
sel.anchor() = sel.cursor() = cursor;
}
selections.sort_and_merge_overlapping();
}
void insert(ConstArrayView<String> strings)
{
context().selections().insert(strings, InsertMode::InsertCursor);
}
void insert(Codepoint key)
{
String str{key};
context().selections().insert(str, InsertMode::InsertCursor);
context().hooks().run_hook(Hook::InsertChar, str, context());
}
void prepare(InsertMode mode, int count)
{
SelectionList& selections = context().selections();
Buffer& buffer = context().buffer();
switch (mode)
{
case InsertMode::Insert:
for (auto& sel : selections)
sel.set(sel.max(), sel.min());
break;
case InsertMode::Replace:
selections.erase();
break;
case InsertMode::Append:
for (auto& sel : selections)
{
sel.set(sel.min(), buffer.char_next(sel.max()));
if (sel.cursor() == buffer.end_coord())
buffer.insert(buffer.end_coord(), "\n");
}
break;
case InsertMode::AppendAtLineEnd:
for (auto& sel : selections)
sel.set({sel.max().line, buffer[sel.max().line].length() - 1});
break;
case InsertMode::OpenLineBelow:
{
Vector<Selection> new_sels;
count = count > 0 ? count : 1;
LineCount inserted_count = 0;
for (auto sel : selections)
{
buffer.insert(sel.max().line + inserted_count + 1,
String{'\n', CharCount{count}});
for (int i = 0; i < count; ++i)
new_sels.push_back({sel.max().line + inserted_count + i + 1});
inserted_count += count;
}
selections.set(std::move(new_sels),
selections.main_index() * count + count - 1);
context().hooks().run_hook(Hook::InsertChar, "\n", context());
break;
}
case InsertMode::OpenLineAbove:
{
Vector<Selection> new_sels;
count = count > 0 ? count : 1;
LineCount inserted_count = 0;
for (auto sel : selections)
{
buffer.insert(sel.min().line + inserted_count,
String{'\n', CharCount{count}});
for (int i = 0; i < count; ++i)
new_sels.push_back({sel.min().line + inserted_count + i});
inserted_count += count;
}
selections.set(std::move(new_sels),
selections.main_index() * count + count - 1);
context().hooks().run_hook(Hook::InsertChar, "\n", context());
break;
}
case InsertMode::InsertAtLineBegin:
for (auto& sel : selections)
{
BufferCoord pos = sel.min().line;
auto pos_non_blank = buffer.iterator_at(pos);
while (*pos_non_blank == ' ' or *pos_non_blank == '\t')
++pos_non_blank;
if (*pos_non_blank != '\n')
pos = pos_non_blank.coord();
sel.set(pos);
}
break;
case InsertMode::InsertAtNextLineBegin:
case InsertMode::InsertCursor:
kak_assert(false); // invalid for interactive insert
break;
}
if (mode != InsertMode::Append and mode != InsertMode::Replace)
selections.sort_and_merge_overlapping();
selections.check_invariant();
buffer.check_invariant();
}
ScopedEdition m_edition;
InsertCompleter m_completer;
const bool m_restore_cursor;
bool m_auto_complete;
Timer m_idle_timer;
MouseHandler m_mouse_handler;
ScopedSetBool m_disable_hooks;
};
}
InputHandler::InputHandler(SelectionList selections, Context::Flags flags, String name)
: m_context(*this, std::move(selections), flags, std::move(name))
{
m_mode_stack.emplace_back(new InputModes::Normal(*this));
current_mode().on_enabled();
}
InputHandler::~InputHandler() = default;
void InputHandler::push_mode(InputMode* new_mode)
{
StringView prev_name = current_mode().name();
current_mode().on_disabled(true);
m_mode_stack.emplace_back(new_mode);
new_mode->on_enabled();
context().hooks().run_hook(Hook::ModeChange, format("push:{}:{}", prev_name, new_mode->name()), context());
}
void InputHandler::pop_mode(InputMode* mode)
{
kak_assert(m_mode_stack.back().get() == mode);
kak_assert(m_mode_stack.size() > 1);
StringView prev_name = mode->name();
current_mode().on_disabled(false);
m_mode_stack.pop_back();
current_mode().on_enabled();
context().hooks().run_hook(Hook::ModeChange, format("pop:{}:{}", prev_name, current_mode().name()), context());
}
void InputHandler::reset_normal_mode()
{
kak_assert(dynamic_cast<InputModes::Normal*>(m_mode_stack[0].get()) != nullptr);
if (m_mode_stack.size() == 1)
return;
while (m_mode_stack.size() > 1)
pop_mode(m_mode_stack.back().get());
}
void InputHandler::insert(InsertMode mode, int count)
{
push_mode(new InputModes::Insert(*this, mode, count));
}
void InputHandler::repeat_last_insert()
{
if (m_last_insert.keys.empty())
return;
if (dynamic_cast<InputModes::Normal*>(&current_mode()) == nullptr or
m_last_insert.recording)
throw runtime_error{"repeating last insert not available in this context"};
Vector<Key> keys;
swap(keys, m_last_insert.keys);
ScopedSetBool disable_hooks(context().hooks_disabled(),
m_last_insert.disable_hooks);
push_mode(new InputModes::Insert(*this, m_last_insert.mode, m_last_insert.count));
for (auto& key : keys)
{
// refill last_insert, this is very inefficient, but necessary at the moment
// to properly handle insert completion
m_last_insert.keys.push_back(key);
current_mode().handle_key(key);
}
kak_assert(dynamic_cast<InputModes::Normal*>(&current_mode()) != nullptr);
}
void InputHandler::prompt(StringView prompt, String initstr, String emptystr,
Face prompt_face, PromptFlags flags, char history_register,
PromptCompleter completer, PromptCallback callback)
{
push_mode(new InputModes::Prompt(*this, prompt, std::move(initstr), std::move(emptystr),
prompt_face, flags, history_register,
std::move(completer), std::move(callback)));
}
void InputHandler::set_prompt_face(Face prompt_face)
{
InputModes::Prompt* prompt = dynamic_cast<InputModes::Prompt*>(&current_mode());
if (prompt)
prompt->set_prompt_face(prompt_face);
}
void InputHandler::menu(Vector<DisplayLine> choices, MenuCallback callback)
{
push_mode(new InputModes::Menu(*this, std::move(choices), std::move(callback)));
}
void InputHandler::on_next_key(KeymapMode keymap_mode, KeyCallback callback)
{
push_mode(new InputModes::NextKey(*this, keymap_mode, std::move(callback)));
}
InputHandler::ScopedForceNormal::ScopedForceNormal(InputHandler& handler, NormalParams params)
: m_handler(handler), m_mode(nullptr)
{
if (handler.m_mode_stack.size() != 1)
{
handler.push_mode(new InputModes::Normal(handler));
m_mode = handler.m_mode_stack.back().get();
}
static_cast<InputModes::Normal*>(handler.m_mode_stack.back().get())->m_params = params;
}
InputHandler::ScopedForceNormal::~ScopedForceNormal()
{
if (not m_mode)
return;
kak_assert(m_handler.m_mode_stack.size() > 1);
if (m_mode == m_handler.m_mode_stack.back().get())
m_handler.pop_mode(m_mode);
else
{
auto it = find_if(m_handler.m_mode_stack,
[this](const RefPtr<InputMode>& m)
{ return m.get() == m_mode; });
kak_assert(it != m_handler.m_mode_stack.end());
m_handler.m_mode_stack.erase(it);
}
}
static bool is_valid(Key key)
{
constexpr Key::Modifiers valid_mods = (Key::Modifiers::Control | Key::Modifiers::Alt | Key::Modifiers::Shift);
return key != Key::Invalid and
((key.modifiers & ~valid_mods) or key.key <= 0x10FFFF);
}
void InputHandler::handle_key(Key key)
{
if (not is_valid(key))
return;
const bool was_recording = is_recording();
++m_handle_key_level;
auto dec = on_scope_end([this]{ --m_handle_key_level; });
auto process_key = [&](Key key) {
if (m_last_insert.recording)
m_last_insert.keys.push_back(key);
current_mode().handle_key(key);
};
const auto keymap_mode = current_mode().keymap_mode();
KeymapManager& keymaps = m_context.keymaps();
if (keymaps.is_mapped(key, keymap_mode) and not m_context.keymaps_disabled())
{
ScopedSetBool disable_history{context().history_disabled()};
for (auto& k : keymaps.get_mapping(key, keymap_mode).keys)
process_key(k);
}
else
process_key(key);
// do not record the key that made us enter or leave recording mode,
// and the ones that are triggered recursively by previous keys.
if (was_recording and is_recording() and m_handle_key_level == m_recording_level)
m_recorded_keys += key_to_str(key);
if (m_handle_key_level < m_recording_level)
{
write_to_debug_buffer("Macro recording started but not finished");
m_recording_reg = 0;
m_recording_level = -1;
}
}
void InputHandler::start_recording(char reg)
{
kak_assert(m_recording_reg == 0);
m_recording_level = m_handle_key_level;
m_recorded_keys = "";
m_recording_reg = reg;
}
bool InputHandler::is_recording() const
{
return m_recording_reg != 0;
}
void InputHandler::stop_recording()
{
kak_assert(m_recording_reg != 0);
if (not m_recorded_keys.empty())
RegisterManager::instance()[m_recording_reg].set(
context(), {m_recorded_keys});
m_recording_reg = 0;
m_recording_level = -1;
}
DisplayLine InputHandler::mode_line() const
{
return current_mode().mode_line();
}
std::pair<CursorMode, DisplayCoord> InputHandler::get_cursor_info() const
{
return current_mode().get_cursor_info();
}
bool show_auto_info_ifn(StringView title, StringView info, AutoInfo mask, const Context& context)
{
if (not (context.options()["autoinfo"].get<AutoInfo>() & mask) or
not context.has_client())
return false;
context.client().info_show(title.str(), info.str(), {}, InfoStyle::Prompt);
return true;
}
void hide_auto_info_ifn(const Context& context, bool hide)
{
if (hide)
context.client().info_hide();
}
void scroll_window(Context& context, LineCount offset, bool adapt_cursor)
{
Window& window = context.window();
Buffer& buffer = context.buffer();
DisplayCoord win_pos = window.position();
DisplayCoord win_dim = window.dimensions();
const DisplayCoord max_offset{(win_dim.line - 1)/2, (win_dim.column - 1)/2};
const DisplayCoord scrolloff =
std::min(context.options()["scrolloff"].get<DisplayCoord>(), max_offset);
const LineCount line_count = buffer.line_count();
win_pos.line = clamp(win_pos.line + offset, 0_line, line_count-1);
window.set_position(win_pos);
if (not adapt_cursor)
return;
SelectionList& selections = context.selections();
const BufferCoord cursor = selections.main().cursor();
auto line = clamp(cursor.line, win_pos.line + scrolloff.line,
win_pos.line + win_dim.line - 1 - scrolloff.line);
line = clamp(line, 0_line, line_count-1);
using std::min; using std::max;
// This is not exactly a clamp, and must be done in this order as
// byte_count_to could return line length
auto col = min(max(cursor.column, buffer[line].byte_count_to(win_pos.column)),
buffer[line].length()-1);
selections = SelectionList{buffer, BufferCoord{line, col}};
}
}