cosmic-text/src/edit/editor.rs
2023-06-08 20:04:56 +01:00

874 lines
32 KiB
Rust

// SPDX-License-Identifier: MIT OR Apache-2.0
#[cfg(not(feature = "std"))]
use alloc::string::String;
use core::{
cmp::{self, Ordering},
iter::once,
};
use unicode_segmentation::UnicodeSegmentation;
#[cfg(feature = "swash")]
use crate::Color;
use crate::{
Action, Affinity, AttrsList, Buffer, BufferLine, Cursor, Edit, FontSystem, LayoutCursor,
Shaping,
};
/// A wrapper of [`Buffer`] for easy editing
pub struct Editor {
buffer: Buffer,
cursor: Cursor,
cursor_x_opt: Option<i32>,
select_opt: Option<Cursor>,
cursor_moved: bool,
}
impl Editor {
/// Create a new [`Editor`] with the provided [`Buffer`]
pub fn new(buffer: Buffer) -> Self {
Self {
buffer,
cursor: Cursor::default(),
cursor_x_opt: None,
select_opt: None,
cursor_moved: false,
}
}
/// Create a new [`Editor`] with the provided [`Buffer`] and [`Cursor`]
pub fn new_with_cursor(buffer: Buffer, cursor: Cursor) -> Self {
Self {
buffer,
cursor,
cursor_x_opt: None,
select_opt: None,
cursor_moved: false,
}
}
fn set_layout_cursor(&mut self, font_system: &mut FontSystem, cursor: LayoutCursor) {
let layout = self
.buffer
.line_layout(font_system, cursor.line)
.expect("layout not found");
let layout_line = match layout.get(cursor.layout) {
Some(some) => some,
None => match layout.last() {
Some(some) => some,
None => todo!("layout cursor in line with no layouts"),
},
};
let (new_index, new_affinity) = match layout_line.glyphs.get(cursor.glyph) {
Some(glyph) => (glyph.start, Affinity::After),
None => match layout_line.glyphs.last() {
Some(glyph) => (glyph.end, Affinity::Before),
//TODO: is this correct?
None => (0, Affinity::After),
},
};
if self.cursor.line != cursor.line
|| self.cursor.index != new_index
|| self.cursor.affinity != new_affinity
{
self.cursor.line = cursor.line;
self.cursor.index = new_index;
self.cursor.affinity = new_affinity;
self.buffer.set_redraw(true);
}
}
}
impl Edit for Editor {
fn buffer(&self) -> &Buffer {
&self.buffer
}
fn buffer_mut(&mut self) -> &mut Buffer {
&mut self.buffer
}
fn cursor(&self) -> Cursor {
self.cursor
}
fn select_opt(&self) -> Option<Cursor> {
self.select_opt
}
fn set_select_opt(&mut self, select_opt: Option<Cursor>) {
if self.select_opt != select_opt {
self.select_opt = select_opt;
self.buffer.set_redraw(true);
}
}
fn shape_as_needed(&mut self, font_system: &mut FontSystem) {
if self.cursor_moved {
self.buffer.shape_until_cursor(font_system, self.cursor);
self.cursor_moved = false;
} else {
self.buffer.shape_until_scroll(font_system);
}
}
fn copy_selection(&mut self) -> Option<String> {
let select = self.select_opt?;
let (start, end) = match select.line.cmp(&self.cursor.line) {
cmp::Ordering::Greater => (self.cursor, select),
cmp::Ordering::Less => (select, self.cursor),
cmp::Ordering::Equal => {
/* select.line == self.cursor.line */
if select.index < self.cursor.index {
(select, self.cursor)
} else {
/* select.index >= self.cursor.index */
(self.cursor, select)
}
}
};
let mut selection = String::new();
// Take the selection from the first line
{
// Add selected part of line to string
if start.line == end.line {
selection.push_str(&self.buffer.lines[start.line].text()[start.index..end.index]);
} else {
selection.push_str(&self.buffer.lines[start.line].text()[start.index..]);
selection.push('\n');
}
}
// Take the selection from all interior lines (if they exist)
for line_i in start.line + 1..end.line {
selection.push_str(self.buffer.lines[line_i].text());
selection.push('\n');
}
// Take the selection from the last line
if end.line > start.line {
// Add selected part of line to string
selection.push_str(&self.buffer.lines[end.line].text()[..end.index]);
}
Some(selection)
}
fn delete_selection(&mut self) -> bool {
let select = match self.select_opt.take() {
Some(some) => some,
None => return false,
};
let (start, end) = match select.line.cmp(&self.cursor.line) {
cmp::Ordering::Greater => (self.cursor, select),
cmp::Ordering::Less => (select, self.cursor),
cmp::Ordering::Equal => {
/* select.line == self.cursor.line */
if select.index < self.cursor.index {
(select, self.cursor)
} else {
/* select.index >= self.cursor.index */
(self.cursor, select)
}
}
};
// Reset cursor to start of selection
self.cursor = start;
// Delete the selection from the last line
let end_line_opt = if end.line > start.line {
// Get part of line after selection
let after = self.buffer.lines[end.line].split_off(end.index);
// Remove end line
self.buffer.lines.remove(end.line);
Some(after)
} else {
None
};
// Delete interior lines (in reverse for safety)
for line_i in (start.line + 1..end.line).rev() {
self.buffer.lines.remove(line_i);
}
// Delete the selection from the first line
{
// Get part after selection if start line is also end line
let after_opt = if start.line == end.line {
Some(self.buffer.lines[start.line].split_off(end.index))
} else {
None
};
// Delete selected part of line
self.buffer.lines[start.line].split_off(start.index);
// Re-add part of line after selection
if let Some(after) = after_opt {
self.buffer.lines[start.line].append(after);
}
// Re-add valid parts of end line
if let Some(end_line) = end_line_opt {
self.buffer.lines[start.line].append(end_line);
}
}
true
}
fn insert_string(&mut self, data: &str, attrs_list: Option<AttrsList>) {
self.delete_selection();
let mut remaining_split_len = data.len();
if remaining_split_len == 0 {
return;
}
let line: &mut BufferLine = &mut self.buffer.lines[self.cursor.line];
let insert_line = self.cursor.line + 1;
// Collect text after insertion as a line
let after: BufferLine = line.split_off(self.cursor.index);
let after_len = after.text().len();
// Collect attributes
let mut final_attrs = attrs_list
.unwrap_or_else(|| AttrsList::new(line.attrs_list().get_span(line.text().len())));
// Append the inserted text, line by line
// we want to see a blank entry if the string ends with a newline
let addendum = once("").filter(|_| data.ends_with('\n'));
let mut lines_iter = data.split_inclusive('\n').chain(addendum);
if let Some(data_line) = lines_iter.next() {
let mut these_attrs = final_attrs.split_off(data_line.len());
remaining_split_len -= data_line.len();
core::mem::swap(&mut these_attrs, &mut final_attrs);
line.append(BufferLine::new(
data_line
.strip_suffix(char::is_control)
.unwrap_or(data_line),
these_attrs,
Shaping::Advanced,
));
} else {
panic!("str::lines() did not yield any elements");
}
if let Some(data_line) = lines_iter.next_back() {
remaining_split_len -= data_line.len();
let mut tmp = BufferLine::new(
data_line
.strip_suffix(char::is_control)
.unwrap_or(data_line),
final_attrs.split_off(remaining_split_len),
Shaping::Advanced,
);
tmp.append(after);
self.buffer.lines.insert(insert_line, tmp);
self.cursor.line += 1;
} else {
line.append(after);
}
for data_line in lines_iter.rev() {
remaining_split_len -= data_line.len();
let tmp = BufferLine::new(
data_line
.strip_suffix(char::is_control)
.unwrap_or(data_line),
final_attrs.split_off(remaining_split_len),
Shaping::Advanced,
);
self.buffer.lines.insert(insert_line, tmp);
self.cursor.line += 1;
}
assert_eq!(remaining_split_len, 0);
// Append the text after insertion
self.cursor.index = self.buffer.lines[self.cursor.line].text().len() - after_len;
}
fn action(&mut self, font_system: &mut FontSystem, action: Action) {
let old_cursor = self.cursor;
match action {
Action::Previous => {
let line = &mut self.buffer.lines[self.cursor.line];
if self.cursor.index > 0 {
// Find previous character index
let mut prev_index = 0;
for (i, _) in line.text().grapheme_indices(true) {
if i < self.cursor.index {
prev_index = i;
} else {
break;
}
}
self.cursor.index = prev_index;
self.cursor.affinity = Affinity::After;
self.buffer.set_redraw(true);
} else if self.cursor.line > 0 {
self.cursor.line -= 1;
self.cursor.index = self.buffer.lines[self.cursor.line].text().len();
self.cursor.affinity = Affinity::After;
self.buffer.set_redraw(true);
}
self.cursor_x_opt = None;
}
Action::Next => {
let line = &mut self.buffer.lines[self.cursor.line];
if self.cursor.index < line.text().len() {
for (i, c) in line.text().grapheme_indices(true) {
if i == self.cursor.index {
self.cursor.index += c.len();
self.cursor.affinity = Affinity::Before;
self.buffer.set_redraw(true);
break;
}
}
} else if self.cursor.line + 1 < self.buffer.lines.len() {
self.cursor.line += 1;
self.cursor.index = 0;
self.cursor.affinity = Affinity::Before;
self.buffer.set_redraw(true);
}
self.cursor_x_opt = None;
}
Action::Left => {
let rtl_opt = self.buffer.lines[self.cursor.line]
.shape_opt()
.as_ref()
.map(|shape| shape.rtl);
if let Some(rtl) = rtl_opt {
if rtl {
self.action(font_system, Action::Next);
} else {
self.action(font_system, Action::Previous);
}
}
}
Action::Right => {
let rtl_opt = self.buffer.lines[self.cursor.line]
.shape_opt()
.as_ref()
.map(|shape| shape.rtl);
if let Some(rtl) = rtl_opt {
if rtl {
self.action(font_system, Action::Previous);
} else {
self.action(font_system, Action::Next);
}
}
}
Action::Up => {
//TODO: make this preserve X as best as possible!
let mut cursor = self.buffer.layout_cursor(&self.cursor);
if self.cursor_x_opt.is_none() {
self.cursor_x_opt = Some(
cursor.glyph as i32, //TODO: glyph x position
);
}
if cursor.layout > 0 {
cursor.layout -= 1;
} else if cursor.line > 0 {
cursor.line -= 1;
cursor.layout = usize::max_value();
}
if let Some(cursor_x) = self.cursor_x_opt {
cursor.glyph = cursor_x as usize; //TODO: glyph x position
}
self.set_layout_cursor(font_system, cursor);
}
Action::Down => {
//TODO: make this preserve X as best as possible!
let mut cursor = self.buffer.layout_cursor(&self.cursor);
let layout_len = self
.buffer
.line_layout(font_system, cursor.line)
.expect("layout not found")
.len();
if self.cursor_x_opt.is_none() {
self.cursor_x_opt = Some(
cursor.glyph as i32, //TODO: glyph x position
);
}
if cursor.layout + 1 < layout_len {
cursor.layout += 1;
} else if cursor.line + 1 < self.buffer.lines.len() {
cursor.line += 1;
cursor.layout = 0;
}
if let Some(cursor_x) = self.cursor_x_opt {
cursor.glyph = cursor_x as usize; //TODO: glyph x position
}
self.set_layout_cursor(font_system, cursor);
}
Action::Home => {
let mut cursor = self.buffer.layout_cursor(&self.cursor);
cursor.glyph = 0;
self.set_layout_cursor(font_system, cursor);
self.cursor_x_opt = None;
}
Action::End => {
let mut cursor = self.buffer.layout_cursor(&self.cursor);
cursor.glyph = usize::max_value();
self.set_layout_cursor(font_system, cursor);
self.cursor_x_opt = None;
}
Action::ParagraphStart => {
self.cursor.index = 0;
self.cursor_x_opt = None;
self.buffer.set_redraw(true);
}
Action::ParagraphEnd => {
self.cursor.index = self.buffer.lines[self.cursor.line].text().len();
self.cursor_x_opt = None;
self.buffer.set_redraw(true);
}
Action::PageUp => {
self.action(font_system, Action::Vertical(-self.buffer.size().1 as i32));
}
Action::PageDown => {
self.action(font_system, Action::Vertical(self.buffer.size().1 as i32));
}
Action::Vertical(px) => {
// TODO more efficient
let lines = px / self.buffer.metrics().line_height as i32;
match lines.cmp(&0) {
Ordering::Less => {
for _ in 0..-lines {
self.action(font_system, Action::Up);
}
}
Ordering::Greater => {
for _ in 0..lines {
self.action(font_system, Action::Down);
}
}
Ordering::Equal => {}
}
}
Action::Escape => {
if self.select_opt.take().is_some() {
self.buffer.set_redraw(true);
}
}
Action::Insert(character) => {
if character.is_control() && !['\t', '\n', '\u{92}'].contains(&character) {
// Filter out special chars (except for tab), use Action instead
log::debug!("Refusing to insert control character {:?}", character);
} else if character == '\n' {
self.action(font_system, Action::Enter);
} else {
let mut str_buf = [0u8; 8];
let str_ref = character.encode_utf8(&mut str_buf);
self.insert_string(str_ref, None);
}
}
Action::Enter => {
self.delete_selection();
let new_line = self.buffer.lines[self.cursor.line].split_off(self.cursor.index);
self.cursor.line += 1;
self.cursor.index = 0;
self.buffer.lines.insert(self.cursor.line, new_line);
}
Action::Backspace => {
if self.delete_selection() {
// Deleted selection
} else if self.cursor.index > 0 {
let line = &mut self.buffer.lines[self.cursor.line];
// Get text line after cursor
let after = line.split_off(self.cursor.index);
// Find previous character index
let mut prev_index = 0;
for (i, _) in line.text().char_indices() {
if i < self.cursor.index {
prev_index = i;
} else {
break;
}
}
self.cursor.index = prev_index;
// Remove character
line.split_off(self.cursor.index);
// Add text after cursor
line.append(after);
} else if self.cursor.line > 0 {
let mut line_index = self.cursor.line;
let old_line = self.buffer.lines.remove(line_index);
line_index -= 1;
let line = &mut self.buffer.lines[line_index];
self.cursor.line = line_index;
self.cursor.index = line.text().len();
line.append(old_line);
}
}
Action::Delete => {
if self.delete_selection() {
// Deleted selection
} else if self.cursor.index < self.buffer.lines[self.cursor.line].text().len() {
let line = &mut self.buffer.lines[self.cursor.line];
let range_opt = line
.text()
.grapheme_indices(true)
.take_while(|(i, _)| *i <= self.cursor.index)
.last()
.map(|(i, c)| i..(i + c.len()));
if let Some(range) = range_opt {
self.cursor.index = range.start;
// Get text after deleted EGC
let after = line.split_off(range.end);
// Delete EGC
line.split_off(range.start);
// Add text after deleted EGC
line.append(after);
}
} else if self.cursor.line + 1 < self.buffer.lines.len() {
let old_line = self.buffer.lines.remove(self.cursor.line + 1);
self.buffer.lines[self.cursor.line].append(old_line);
}
}
Action::Click { x, y } => {
self.select_opt = None;
if let Some(new_cursor) = self.buffer.hit(x as f32, y as f32) {
if new_cursor != self.cursor {
let color = self.cursor.color;
self.cursor = new_cursor;
self.cursor.color = color;
self.buffer.set_redraw(true);
}
}
}
Action::Drag { x, y } => {
if self.select_opt.is_none() {
self.select_opt = Some(self.cursor);
self.buffer.set_redraw(true);
}
if let Some(new_cursor) = self.buffer.hit(x as f32, y as f32) {
if new_cursor != self.cursor {
let color = self.cursor.color;
self.cursor = new_cursor;
self.cursor.color = color;
self.buffer.set_redraw(true);
}
}
}
Action::Scroll { lines } => {
let mut scroll = self.buffer.scroll();
scroll += lines;
self.buffer.set_scroll(scroll);
}
Action::PreviousWord => {
let line: &mut BufferLine = &mut self.buffer.lines[self.cursor.line];
if self.cursor.index > 0 {
let mut prev_index = 0;
for (i, _) in line.text().unicode_word_indices() {
if i < self.cursor.index {
prev_index = i;
} else {
break;
}
}
self.cursor.index = prev_index;
self.buffer.set_redraw(true);
} else if self.cursor.line > 0 {
self.cursor.line -= 1;
self.cursor.index = self.buffer.lines[self.cursor.line].text().len();
self.buffer.set_redraw(true);
}
self.cursor_x_opt = None;
}
Action::NextWord => {
let line: &mut BufferLine = &mut self.buffer.lines[self.cursor.line];
if self.cursor.index < line.text().len() {
for (i, word) in line.text().unicode_word_indices() {
let i = i + word.len();
if i > self.cursor.index {
self.cursor.index = i;
self.buffer.set_redraw(true);
break;
}
}
} else if self.cursor.line + 1 < self.buffer.lines.len() {
self.cursor.line += 1;
self.cursor.index = 0;
self.buffer.set_redraw(true);
}
self.cursor_x_opt = None;
}
Action::LeftWord => {
let rtl_opt = self.buffer.lines[self.cursor.line]
.shape_opt()
.as_ref()
.map(|shape| shape.rtl);
if let Some(rtl) = rtl_opt {
if rtl {
self.action(font_system, Action::NextWord);
} else {
self.action(font_system, Action::PreviousWord);
}
}
}
Action::RightWord => {
let rtl_opt = self.buffer.lines[self.cursor.line]
.shape_opt()
.as_ref()
.map(|shape| shape.rtl);
if let Some(rtl) = rtl_opt {
if rtl {
self.action(font_system, Action::PreviousWord);
} else {
self.action(font_system, Action::NextWord);
}
}
}
Action::BufferStart => {
self.cursor.line = 0;
self.cursor.index = 0;
self.cursor_x_opt = None;
}
Action::BufferEnd => {
self.cursor.line = self.buffer.lines.len() - 1;
self.cursor.index = self.buffer.lines[self.cursor.line].text().len();
self.cursor_x_opt = None;
}
}
if old_cursor != self.cursor {
self.cursor_moved = true;
/*TODO
if let Some(glyph) = run.glyphs.get(new_cursor_glyph) {
let font_opt = self.buffer.font_system().get_font(glyph.cache_key.font_id);
let text_glyph = &run.text[glyph.start..glyph.end];
log::debug!(
"{}, {}: '{}' ('{}'): '{}' ({:?})",
self.cursor.line,
self.cursor.index,
font_opt.as_ref().map_or("?", |font| font.info.family.as_str()),
font_opt.as_ref().map_or("?", |font| font.info.post_script_name.as_str()),
text_glyph,
text_glyph
);
}
*/
}
}
/// Draw the editor
#[cfg(feature = "swash")]
fn draw<F>(
&self,
font_system: &mut FontSystem,
cache: &mut crate::SwashCache,
color: Color,
mut f: F,
) where
F: FnMut(i32, i32, u32, u32, Color),
{
let font_size = self.buffer.metrics().font_size;
let line_height = self.buffer.metrics().line_height;
for run in self.buffer.layout_runs() {
let line_i = run.line_i;
let line_y = run.line_y;
let cursor_glyph_opt = |cursor: &Cursor| -> Option<(usize, f32)> {
if cursor.line == line_i {
for (glyph_i, glyph) in run.glyphs.iter().enumerate() {
if cursor.index == glyph.start {
return Some((glyph_i, 0.0));
} else if cursor.index > glyph.start && cursor.index < glyph.end {
// Guess x offset based on characters
let mut before = 0;
let mut total = 0;
let cluster = &run.text[glyph.start..glyph.end];
for (i, _) in cluster.grapheme_indices(true) {
if glyph.start + i < cursor.index {
before += 1;
}
total += 1;
}
let offset = glyph.w * (before as f32) / (total as f32);
return Some((glyph_i, offset));
}
}
match run.glyphs.last() {
Some(glyph) => {
if cursor.index == glyph.end {
return Some((run.glyphs.len(), 0.0));
}
}
None => {
return Some((0, 0.0));
}
}
}
None
};
// Highlight selection (TODO: HIGHLIGHT COLOR!)
if let Some(select) = self.select_opt {
let (start, end) = match select.line.cmp(&self.cursor.line) {
cmp::Ordering::Greater => (self.cursor, select),
cmp::Ordering::Less => (select, self.cursor),
cmp::Ordering::Equal => {
/* select.line == self.cursor.line */
if select.index < self.cursor.index {
(select, self.cursor)
} else {
/* select.index >= self.cursor.index */
(self.cursor, select)
}
}
};
if line_i >= start.line && line_i <= end.line {
let mut range_opt = None;
for glyph in run.glyphs.iter() {
// Guess x offset based on characters
let cluster = &run.text[glyph.start..glyph.end];
let total = cluster.grapheme_indices(true).count();
let mut c_x = glyph.x;
let c_w = glyph.w / total as f32;
for (i, c) in cluster.grapheme_indices(true) {
let c_start = glyph.start + i;
let c_end = glyph.start + i + c.len();
if (start.line != line_i || c_end > start.index)
&& (end.line != line_i || c_start < end.index)
{
range_opt = match range_opt.take() {
Some((min, max)) => Some((
cmp::min(min, c_x as i32),
cmp::max(max, (c_x + c_w) as i32),
)),
None => Some((c_x as i32, (c_x + c_w) as i32)),
};
} else if let Some((min, max)) = range_opt.take() {
f(
min,
(line_y - font_size) as i32,
cmp::max(0, max - min) as u32,
line_height as u32,
Color::rgba(color.r(), color.g(), color.b(), 0x33),
);
}
c_x += c_w;
}
}
if run.glyphs.is_empty() && end.line > line_i {
// Highlight all of internal empty lines
range_opt = Some((0, self.buffer.size().0 as i32));
}
if let Some((mut min, mut max)) = range_opt.take() {
if end.line > line_i {
// Draw to end of line
if run.rtl {
min = 0;
} else {
max = self.buffer.size().0 as i32;
}
}
f(
min,
(line_y - font_size) as i32,
cmp::max(0, max - min) as u32,
line_height as u32,
Color::rgba(color.r(), color.g(), color.b(), 0x33),
);
}
}
}
// Draw cursor
if let Some((cursor_glyph, cursor_glyph_offset)) = cursor_glyph_opt(&self.cursor) {
let x = match run.glyphs.get(cursor_glyph) {
Some(glyph) => {
// Start of detected glyph
if glyph.level.is_rtl() {
(glyph.x + glyph.w - cursor_glyph_offset) as i32
} else {
(glyph.x + cursor_glyph_offset) as i32
}
}
None => match run.glyphs.last() {
Some(glyph) => {
// End of last glyph
if glyph.level.is_rtl() {
glyph.x as i32
} else {
(glyph.x + glyph.w) as i32
}
}
None => {
// Start of empty line
0
}
},
};
f(
x,
(line_y - font_size) as i32,
1,
line_height as u32,
self.cursor.color.unwrap_or(color),
);
}
for glyph in run.glyphs.iter() {
let (cache_key, x_int, y_int) = (glyph.cache_key, glyph.x_int, glyph.y_int);
let glyph_color = match glyph.color_opt {
Some(some) => some,
None => color,
};
cache.with_pixels(font_system, cache_key, glyph_color, |x, y, color| {
f(x_int + x, line_y as i32 + y_int + y, 1, 1, color);
});
}
}
}
}