Skip to content

Commit

Permalink
GTextEditor: Refactor selection into a GTextRange class.
Browse files Browse the repository at this point in the history 
This is a bit more expressive than "selection start + current cursor".
  • Loading branch information
@awesomekling
awesomekling committed Mar 8, 2019
1 parent f40d11f commit 032549d
Show file tree
Hide file tree
Showing 3 changed files with 95 additions and 51 deletions.
5 changes: 3 additions & 2 deletions Applications/TextEditor/main.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -29,8 +29,9 @@ int main(int argc, char** argv)
text_editor->on_cursor_change = [statusbar] (GTextEditor& editor) {
StringBuilder builder;
builder.appendf("Line: %d, Column: %d", editor.cursor().line(), editor.cursor().column());
if (editor.selection_start().is_valid()) {
builder.appendf(" Selection: [%d,%d]-[%d,%d]", editor.selection_start().line(), editor.selection_start().column(), editor.cursor().line(), editor.cursor().column());
auto selection = editor.normalized_selection();
if (selection.is_valid()) {
builder.appendf(" Selection: [%d,%d]-[%d,%d]", selection.start().line(), selection.start().column(), selection.end().line(), selection.end().column());
}
statusbar->set_text(builder.to_string());
};
Expand Down
107 changes: 61 additions & 46 deletions LibGUI/GTextEditor.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -110,9 +110,9 @@ void GTextEditor::mousedown_event(GMouseEvent& event)
if (event.button() == GMouseButton::Left) {
if (event.modifiers() & Mod_Shift) {
if (!has_selection())
m_selection_start = m_cursor;
m_selection.set(m_cursor, { });
} else {
m_selection_start = { };
m_selection.clear();
}

m_in_drag_select = true;
Expand All @@ -122,9 +122,12 @@ void GTextEditor::mousedown_event(GMouseEvent& event)

if (!(event.modifiers() & Mod_Shift)) {
if (!has_selection())
m_selection_start = m_cursor;
m_selection.set(m_cursor, { });
}

if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);

// FIXME: Only update the relevant rects.
update();
return;
Expand All @@ -146,6 +149,7 @@ void GTextEditor::mousemove_event(GMouseEvent& event)
{
if (m_in_drag_select) {
set_cursor(text_position_at(event.position()));
m_selection.set_end(m_cursor);
update();
return;
}
Expand Down Expand Up @@ -184,11 +188,8 @@ void GTextEditor::paint_event(GPaintEvent& event)
int first_visible_line = text_position_at(event.rect().top_left()).line();
int last_visible_line = text_position_at(event.rect().bottom_right()).line();

auto normalized_selection_start = m_selection_start;
auto normalized_selection_end = m_cursor;
if (m_cursor < m_selection_start)
swap(normalized_selection_start, normalized_selection_end);
bool has_selection = m_selection_start.is_valid();
auto selection = normalized_selection();
bool has_selection = selection.is_valid();

painter.set_font(Font::default_font());
for (int i = first_visible_line; i <= last_visible_line; ++i) {
Expand All @@ -214,10 +215,10 @@ void GTextEditor::paint_event(GPaintEvent& event)
if (i == m_cursor.line())
painter.fill_rect(line_rect, Color(230, 230, 230));
painter.draw_text(line_rect, line.characters(), line.length(), TextAlignment::CenterLeft, Color::Black);
bool line_has_selection = has_selection && i >= normalized_selection_start.line() && i <= normalized_selection_end.line();
bool line_has_selection = has_selection && i >= selection.start().line() && i <= selection.end().line();
if (line_has_selection) {
int selection_start_column_on_line = normalized_selection_start.line() == i ? normalized_selection_start.column() : 0;
int selection_end_column_on_line = normalized_selection_end.line() == i ? normalized_selection_end.column() : line.length();
int selection_start_column_on_line = selection.start().line() == i ? selection.start().column() : 0;
int selection_end_column_on_line = selection.end().line() == i ? selection.end().column() : line.length();
int selection_left = selection_start_column_on_line * font().glyph_width('x');
int selection_right = line_rect.left() + selection_end_column_on_line * font().glyph_width('x');
Rect selection_rect { selection_left, line_rect.y(), selection_right - selection_left, line_rect.height() };
Expand All @@ -244,13 +245,13 @@ void GTextEditor::paint_event(GPaintEvent& event)

void GTextEditor::toggle_selection_if_needed_for_event(const GKeyEvent& event)
{
if (event.shift() && !m_selection_start.is_valid()) {
m_selection_start = m_cursor;
if (event.shift() && !m_selection.is_valid()) {
m_selection.set(m_cursor, { });
update();
return;
}
if (!event.shift() && m_selection_start.is_valid()) {
m_selection_start = { };
if (!event.shift() && m_selection.is_valid()) {
m_selection.clear();
update();
return;
}
Expand All @@ -264,6 +265,8 @@ void GTextEditor::keydown_event(GKeyEvent& event)
int new_column = min(m_cursor.column(), m_lines[new_line]->length());
toggle_selection_if_needed_for_event(event);
set_cursor(new_line, new_column);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
}
return;
}
Expand All @@ -273,6 +276,8 @@ void GTextEditor::keydown_event(GKeyEvent& event)
int new_column = min(m_cursor.column(), m_lines[new_line]->length());
toggle_selection_if_needed_for_event(event);
set_cursor(new_line, new_column);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
}
return;
}
Expand All @@ -282,6 +287,8 @@ void GTextEditor::keydown_event(GKeyEvent& event)
int new_column = min(m_cursor.column(), m_lines[new_line]->length());
toggle_selection_if_needed_for_event(event);
set_cursor(new_line, new_column);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
}
return;
}
Expand All @@ -291,6 +298,8 @@ void GTextEditor::keydown_event(GKeyEvent& event)
int new_column = min(m_cursor.column(), m_lines[new_line]->length());
toggle_selection_if_needed_for_event(event);
set_cursor(new_line, new_column);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
}
return;
}
Expand All @@ -299,6 +308,8 @@ void GTextEditor::keydown_event(GKeyEvent& event)
int new_column = m_cursor.column() - 1;
toggle_selection_if_needed_for_event(event);
set_cursor(m_cursor.line(), new_column);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
}
return;
}
Expand All @@ -307,32 +318,44 @@ void GTextEditor::keydown_event(GKeyEvent& event)
int new_column = m_cursor.column() + 1;
toggle_selection_if_needed_for_event(event);
set_cursor(m_cursor.line(), new_column);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
}
return;
}
if (!event.ctrl() && event.key() == KeyCode::Key_Home) {
toggle_selection_if_needed_for_event(event);
set_cursor(m_cursor.line(), 0);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
return;
}
if (!event.ctrl() && event.key() == KeyCode::Key_End) {
toggle_selection_if_needed_for_event(event);
set_cursor(m_cursor.line(), current_line().length());
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
return;
}
if (event.ctrl() && event.key() == KeyCode::Key_Home) {
toggle_selection_if_needed_for_event(event);
set_cursor(0, 0);
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
return;
}
if (event.ctrl() && event.key() == KeyCode::Key_End) {
toggle_selection_if_needed_for_event(event);
set_cursor(line_count() - 1, m_lines[line_count() - 1]->length());
if (m_selection.start().is_valid())
m_selection.set_end(m_cursor);
return;
}
if (event.modifiers() == Mod_Ctrl && event.key() == KeyCode::Key_A) {
m_selection_start = { 0, 0 };
set_cursor(line_count() - 1, m_lines[line_count() - 1]->length());
GTextPosition start_of_document { 0, 0 };
GTextPosition end_of_document { line_count() - 1, m_lines[line_count() - 1]->length() };
m_selection.set(start_of_document, end_of_document);
set_cursor(end_of_document);
update();
return;
}
Expand Down Expand Up @@ -650,19 +673,14 @@ String GTextEditor::selected_text() const
if (!has_selection())
return { };

auto normalized_selection_start = m_selection_start;
auto normalized_selection_end = m_cursor;
if (m_cursor < m_selection_start)
swap(normalized_selection_start, normalized_selection_end);

auto selection = normalized_selection();
StringBuilder builder;

for (int i = normalized_selection_start.line(); i <= normalized_selection_end.line(); ++i) {
for (int i = selection.start().line(); i <= selection.end().line(); ++i) {
auto& line = *m_lines[i];
int selection_start_column_on_line = normalized_selection_start.line() == i ? normalized_selection_start.column() : 0;
int selection_end_column_on_line = normalized_selection_end.line() == i ? normalized_selection_end.column() : line.length();
int selection_start_column_on_line = selection.start().line() == i ? selection.start().column() : 0;
int selection_end_column_on_line = selection.end().line() == i ? selection.end().column() : line.length();
builder.append(line.characters() + selection_start_column_on_line, selection_end_column_on_line - selection_start_column_on_line);
if (i != normalized_selection_end.line())
if (i != selection.end().line())
builder.append('\n');
}

Expand All @@ -674,50 +692,47 @@ void GTextEditor::delete_selection()
if (!has_selection())
return;

auto normalized_selection_start = m_selection_start;
auto normalized_selection_end = m_cursor;
if (m_cursor < m_selection_start)
swap(normalized_selection_start, normalized_selection_end);
auto selection = normalized_selection();

// First delete all the lines in between the first and last one.
for (int i = normalized_selection_start.line() + 1; i < normalized_selection_end.line();) {
for (int i = selection.start().line() + 1; i < selection.end().line();) {
m_lines.remove(i);
normalized_selection_end.set_line(normalized_selection_end.line() - 1);
selection.end().set_line(selection.end().line() - 1);
}

if (normalized_selection_start.line() == normalized_selection_end.line()) {
if (selection.start().line() == selection.end().line()) {
// Delete within same line.
auto& line = *m_lines[normalized_selection_start.line()];
bool whole_line_is_selected = normalized_selection_start.column() == 0 && normalized_selection_end.column() == line.length();
auto& line = *m_lines[selection.start().line()];
bool whole_line_is_selected = selection.start().column() == 0 && selection.end().column() == line.length();
if (whole_line_is_selected) {
line.clear();
} else {
auto before_selection = String(line.characters(), line.length()).substring(0, normalized_selection_start.column());
auto after_selection = String(line.characters(), line.length()).substring(normalized_selection_end.column(), line.length() - normalized_selection_end.column());
auto before_selection = String(line.characters(), line.length()).substring(0, selection.start().column());
auto after_selection = String(line.characters(), line.length()).substring(selection.end().column(), line.length() - selection.end().column());
StringBuilder builder(before_selection.length() + after_selection.length());
builder.append(before_selection);
builder.append(after_selection);
line.set_text(builder.to_string());
}
} else {
// Delete across a newline, merging lines.
ASSERT(normalized_selection_start.line() == normalized_selection_end.line() - 1);
auto& first_line = *m_lines[normalized_selection_start.line()];
auto& second_line = *m_lines[normalized_selection_end.line()];
auto before_selection = String(first_line.characters(), first_line.length()).substring(0, normalized_selection_start.column());
auto after_selection = String(second_line.characters(), second_line.length()).substring(normalized_selection_end.column(), second_line.length() - normalized_selection_end.column());
ASSERT(selection.start().line() == selection.end().line() - 1);
auto& first_line = *m_lines[selection.start().line()];
auto& second_line = *m_lines[selection.end().line()];
auto before_selection = String(first_line.characters(), first_line.length()).substring(0, selection.start().column());
auto after_selection = String(second_line.characters(), second_line.length()).substring(selection.end().column(), second_line.length() - selection.end().column());
StringBuilder builder(before_selection.length() + after_selection.length());
builder.append(before_selection);
builder.append(after_selection);
first_line.set_text(builder.to_string());
m_lines.remove(normalized_selection_end.line());
m_lines.remove(selection.end().line());
}

if (m_lines.is_empty())
m_lines.append(make<Line>());

m_selection_start = { };
set_cursor(normalized_selection_start);
m_selection.clear();
set_cursor(selection.start());
update();
}

Expand Down
34 changes: 31 additions & 3 deletions LibGUI/GTextEditor.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,34 @@ class GTextPosition {
int m_column { -1 };
};

class GTextRange {
public:
GTextRange() { }
GTextRange(const GTextPosition& start, const GTextPosition& end) : m_start(start) , m_end(end) { }

bool is_valid() const { return m_start.is_valid() && m_end.is_valid(); }
void clear() { m_start = { }; m_end = { }; }

GTextPosition& start() { return m_start; }
GTextPosition& end() { return m_end; }
const GTextPosition& start() const { return m_start; }
const GTextPosition& end() const { return m_end; }

GTextRange normalized() const { return GTextRange(normalized_start(), normalized_end()); }

void set_start(const GTextPosition& position) { m_start = position; }
void set_end(const GTextPosition& position) { m_end = position; }

void set(const GTextPosition& start, const GTextPosition& end) { m_start = start; m_end = end; }

private:
GTextPosition normalized_start() const { return m_start < m_end ? m_start : m_end; }
GTextPosition normalized_end() const { return m_start < m_end ? m_end : m_start; }

GTextPosition m_start;
GTextPosition m_end;
};

class GTextEditor : public GWidget {
public:
explicit GTextEditor(GWidget* parent);
Expand All @@ -49,12 +77,12 @@ class GTextEditor : public GWidget {
int line_height() const { return font().glyph_height() + m_line_spacing; }
int padding() const { return 3; }
GTextPosition cursor() const { return m_cursor; }
GTextPosition selection_start() const { return m_selection_start; }
GTextRange normalized_selection() const { return m_selection.normalized(); }
int glyph_width() const { return font().glyph_width('x'); }

bool write_to_file(const String& path);

bool has_selection() const { return m_selection_start.is_valid(); }
bool has_selection() const { return m_selection.is_valid(); }
String selected_text() const;

void cut();
Expand Down Expand Up @@ -121,5 +149,5 @@ class GTextEditor : public GWidget {
bool m_cursor_state { true };
bool m_in_drag_select { false };
int m_line_spacing { 2 };
GTextPosition m_selection_start;
GTextRange m_selection;
};

0 comments on commit 032549d

Please sign in to comment.