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use {
super::utils::{coerce_crlf, line_width},
crate::{
menu::{Menu, ReedlineMenu},
painting::PromptLines,
LineBuffer, Prompt,
},
crossterm::{
cursor::{self, MoveTo, MoveUp, RestorePosition, SavePosition},
style::{Attribute, Print, ResetColor, SetAttribute, SetForegroundColor},
terminal::{self, Clear, ClearType, ScrollUp},
QueueableCommand, Result,
},
std::io::Write,
};
fn skip_buffer_lines(string: &str, skip: usize, offset: Option<usize>) -> &str {
let mut matches = string.match_indices('\n');
let index = if skip == 0 {
0
} else {
matches
.clone()
.nth(skip - 1)
.map(|(index, _)| index + 1)
.unwrap_or(string.len())
};
let limit = match offset {
Some(offset) => {
let offset = skip + offset;
matches
.nth(offset)
.map(|(index, _)| index)
.unwrap_or(string.len())
}
None => string.len(),
};
string[index..limit].trim_end_matches('\n')
}
pub type W = std::io::BufWriter<std::io::Stderr>;
pub struct Painter {
stdout: W,
prompt_start_row: u16,
terminal_size: (u16, u16),
last_required_lines: u16,
large_buffer: bool,
}
impl Painter {
pub(crate) fn new(stdout: W) -> Self {
Painter {
stdout,
prompt_start_row: 0,
terminal_size: (0, 0),
last_required_lines: 0,
large_buffer: false,
}
}
pub fn screen_height(&self) -> u16 {
self.terminal_size.1
}
pub fn screen_width(&self) -> u16 {
self.terminal_size.0
}
pub fn remaining_lines(&self) -> u16 {
self.screen_height() - self.prompt_start_row
}
pub(crate) fn initialize_prompt_position(&mut self) -> Result<()> {
self.terminal_size = {
let size = terminal::size()?;
if size == (0, 0) {
(80, 24)
} else {
size
}
};
let (column, row) = cursor::position()?;
let new_row = if column > 0 { row + 1 } else { row };
let new_row = if new_row == self.screen_height() {
self.print_crlf()?;
new_row.saturating_sub(1)
} else {
new_row
};
self.prompt_start_row = new_row;
Ok(())
}
pub(crate) fn repaint_buffer(
&mut self,
prompt: &dyn Prompt,
lines: &PromptLines,
menu: Option<&ReedlineMenu>,
use_ansi_coloring: bool,
) -> Result<()> {
self.stdout.queue(cursor::Hide)?;
let screen_width = self.screen_width();
let screen_height = self.screen_height();
let remaining_lines = self.remaining_lines();
let required_lines = lines.required_lines(screen_width, menu);
self.large_buffer = required_lines >= screen_height;
if self.large_buffer {
self.prompt_start_row = 0;
} else if required_lines >= remaining_lines {
let extra = required_lines.saturating_sub(remaining_lines);
self.stdout.queue(ScrollUp(extra))?;
self.prompt_start_row = self.prompt_start_row.saturating_sub(extra);
}
self.stdout
.queue(cursor::MoveTo(0, self.prompt_start_row))?
.queue(Clear(ClearType::FromCursorDown))?;
if self.large_buffer {
self.print_large_buffer(prompt, lines, menu, use_ansi_coloring)?;
} else {
self.print_small_buffer(prompt, lines, menu, use_ansi_coloring)?;
}
self.last_required_lines = required_lines;
self.stdout.queue(RestorePosition)?.queue(cursor::Show)?;
self.stdout.flush()
}
fn print_right_prompt(&mut self, lines: &PromptLines) -> Result<()> {
let prompt_length_right = line_width(&lines.prompt_str_right);
let start_position = self
.screen_width()
.saturating_sub(prompt_length_right as u16);
let input_width = lines.estimate_first_input_line_width();
if input_width <= start_position {
self.stdout
.queue(SavePosition)?
.queue(cursor::MoveTo(start_position, self.prompt_start_row))?
.queue(Print(&coerce_crlf(&lines.prompt_str_right)))?
.queue(RestorePosition)?;
}
Ok(())
}
fn print_menu(
&mut self,
menu: &dyn Menu,
lines: &PromptLines,
use_ansi_coloring: bool,
) -> Result<()> {
let screen_width = self.screen_width();
let screen_height = self.screen_height();
let cursor_distance = lines.distance_from_prompt(screen_width);
let starting_row = if cursor_distance >= screen_height.saturating_sub(1) {
screen_height.saturating_sub(menu.min_rows())
} else {
self.prompt_start_row + cursor_distance + 1
};
let remaining_lines = screen_height.saturating_sub(starting_row);
let menu_string = menu.menu_string(remaining_lines, use_ansi_coloring);
self.stdout
.queue(cursor::MoveTo(0, starting_row))?
.queue(Clear(ClearType::FromCursorDown))?
.queue(Print(menu_string.trim_end_matches('\n')))?;
Ok(())
}
fn print_small_buffer(
&mut self,
prompt: &dyn Prompt,
lines: &PromptLines,
menu: Option<&ReedlineMenu>,
use_ansi_coloring: bool,
) -> Result<()> {
if use_ansi_coloring {
self.stdout
.queue(SetForegroundColor(prompt.get_prompt_color()))?
.queue(SetAttribute(Attribute::Bold))?;
}
self.stdout
.queue(Print(&coerce_crlf(&lines.prompt_str_left)))?;
let prompt_indicator = match menu {
Some(menu) => menu.indicator(),
None => &lines.prompt_indicator,
};
if use_ansi_coloring {
self.stdout
.queue(SetForegroundColor(prompt.get_indicator_color()))?
.queue(SetAttribute(Attribute::Bold))?;
}
self.stdout.queue(Print(&coerce_crlf(prompt_indicator)))?;
if use_ansi_coloring {
self.stdout
.queue(SetForegroundColor(prompt.get_prompt_right_color()))?
.queue(SetAttribute(Attribute::Bold))?;
}
self.print_right_prompt(lines)?;
if use_ansi_coloring {
self.stdout.queue(ResetColor)?;
}
self.stdout
.queue(Print(&lines.before_cursor))?
.queue(SavePosition)?
.queue(Print(&lines.after_cursor))?;
if let Some(menu) = menu {
self.print_menu(menu, lines, use_ansi_coloring)?;
} else {
self.stdout.queue(Print(&lines.hint))?;
}
Ok(())
}
fn print_large_buffer(
&mut self,
prompt: &dyn Prompt,
lines: &PromptLines,
menu: Option<&ReedlineMenu>,
use_ansi_coloring: bool,
) -> Result<()> {
let screen_width = self.screen_width();
let screen_height = self.screen_height();
let cursor_distance = lines.distance_from_prompt(screen_width);
let remaining_lines = screen_height.saturating_sub(cursor_distance);
let prompt_lines = lines.prompt_lines_with_wrap(screen_width) as usize;
let prompt_indicator = match menu {
Some(menu) => menu.indicator(),
None => &lines.prompt_indicator,
};
let prompt_indicator_lines = prompt_indicator.lines().count();
let before_cursor_lines = lines.before_cursor.lines().count();
let total_lines_before = prompt_lines + prompt_indicator_lines + before_cursor_lines - 1;
let extra_rows = (total_lines_before).saturating_sub(screen_height as usize);
if use_ansi_coloring {
self.stdout
.queue(SetForegroundColor(prompt.get_prompt_color()))?;
}
let prompt_skipped = skip_buffer_lines(&lines.prompt_str_left, extra_rows, None);
self.stdout.queue(Print(&coerce_crlf(prompt_skipped)))?;
if extra_rows == 0 {
self.print_right_prompt(lines)?;
}
let extra_rows = extra_rows.saturating_sub(prompt_lines);
let indicator_skipped = skip_buffer_lines(prompt_indicator, extra_rows, None);
self.stdout.queue(Print(&coerce_crlf(indicator_skipped)))?;
if use_ansi_coloring {
self.stdout.queue(ResetColor)?;
}
let offset = menu.and_then(|menu| {
if cursor_distance >= screen_height.saturating_sub(1) {
let rows = lines
.before_cursor
.lines()
.count()
.saturating_sub(extra_rows)
.saturating_sub(menu.min_rows() as usize);
Some(rows)
} else {
None
}
});
let before_cursor_skipped = skip_buffer_lines(&lines.before_cursor, extra_rows, offset);
self.stdout.queue(Print(before_cursor_skipped))?;
self.stdout.queue(SavePosition)?;
if let Some(menu) = menu {
self.print_menu(menu, lines, use_ansi_coloring)?;
} else {
let offset = remaining_lines.saturating_sub(1) as usize;
let after_cursor_skipped = skip_buffer_lines(&lines.after_cursor, 0, Some(offset));
self.stdout.queue(Print(after_cursor_skipped))?;
let hint_skipped = skip_buffer_lines(&lines.hint, 0, Some(offset));
self.stdout.queue(Print(hint_skipped))?;
}
Ok(())
}
pub(crate) fn handle_resize(&mut self, width: u16, height: u16) {
let prev_terminal_size = self.terminal_size;
let prev_prompt_row = self.prompt_start_row;
self.terminal_size = (width, height);
if prev_prompt_row >= (height - 1) {
self.prompt_start_row = height - 2;
} else if prev_terminal_size.1 < height {
self.prompt_start_row = prev_prompt_row + (height - prev_terminal_size.1);
}
}
pub(crate) fn paint_line(&mut self, line: &str) -> Result<()> {
self.stdout.queue(Print(line))?.queue(Print("\r\n"))?;
self.stdout.flush()
}
pub(crate) fn print_crlf(&mut self) -> Result<()> {
self.stdout.queue(Print("\r\n"))?;
self.stdout.flush()
}
pub(crate) fn clear_screen(&mut self) -> Result<()> {
self.stdout.queue(cursor::Hide)?;
let (_, num_lines) = terminal::size()?;
for _ in 0..2 * num_lines {
self.stdout.queue(Print("\n"))?;
}
self.stdout.queue(MoveTo(0, 0))?;
self.stdout.queue(cursor::Show)?;
self.stdout.flush()?;
self.initialize_prompt_position()
}
pub(crate) fn clear_scrollback(&mut self) -> Result<()> {
self.stdout
.queue(crossterm::terminal::Clear(ClearType::All))?
.queue(crossterm::terminal::Clear(ClearType::Purge))?
.queue(cursor::MoveTo(0, 0))?
.flush()?;
self.initialize_prompt_position()
}
pub(crate) fn move_cursor_to_end(&mut self) -> Result<()> {
let final_row = self.prompt_start_row + self.last_required_lines;
let scroll = final_row.saturating_sub(self.screen_height() - 1);
if scroll != 0 {
self.stdout.queue(ScrollUp(scroll))?;
}
self.stdout
.queue(MoveTo(0, final_row.min(self.screen_height() - 1)))?;
self.stdout.flush()
}
pub fn print_external_message(
&mut self,
messages: Vec<String>,
line_buffer: &LineBuffer,
prompt: &dyn Prompt,
) -> Result<()> {
let prompt_len = prompt.render_prompt_right().len() + 3;
let mut buffer_num_lines = 0_u16;
for (i, line) in line_buffer.get_buffer().lines().enumerate() {
let screen_lines = match i {
0 => {
let first_line_len = line.len() + prompt_len;
((first_line_len as u16) / (self.screen_width())) + 1
}
_ => {
((line.len() as u16) / self.screen_width()) + 1
}
};
buffer_num_lines = buffer_num_lines.saturating_add(screen_lines);
}
if buffer_num_lines > 1 {
self.stdout.queue(MoveUp(buffer_num_lines - 1))?;
}
let erase_line = format!("\r{}\r", " ".repeat(self.screen_width().into()));
for line in messages {
self.stdout.queue(Print(&erase_line))?;
self.paint_line(&line)?;
let new_start = self.prompt_start_row.saturating_add(1);
let height = self.screen_height();
if new_start >= height {
self.prompt_start_row = height - 1;
} else {
self.prompt_start_row = new_start;
}
}
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::*;
use pretty_assertions::assert_eq;
#[test]
fn test_skip_lines() {
let string = "sentence1\nsentence2\nsentence3\n";
assert_eq!(skip_buffer_lines(string, 1, None), "sentence2\nsentence3");
assert_eq!(skip_buffer_lines(string, 2, None), "sentence3");
assert_eq!(skip_buffer_lines(string, 3, None), "");
assert_eq!(skip_buffer_lines(string, 4, None), "");
}
#[test]
fn test_skip_lines_no_newline() {
let string = "sentence1";
assert_eq!(skip_buffer_lines(string, 0, None), "sentence1");
assert_eq!(skip_buffer_lines(string, 1, None), "");
}
#[test]
fn test_skip_lines_with_limit() {
let string = "sentence1\nsentence2\nsentence3\nsentence4\nsentence5";
assert_eq!(
skip_buffer_lines(string, 1, Some(1)),
"sentence2\nsentence3",
);
assert_eq!(
skip_buffer_lines(string, 1, Some(2)),
"sentence2\nsentence3\nsentence4",
);
assert_eq!(
skip_buffer_lines(string, 2, Some(1)),
"sentence3\nsentence4",
);
assert_eq!(
skip_buffer_lines(string, 1, Some(10)),
"sentence2\nsentence3\nsentence4\nsentence5",
);
assert_eq!(
skip_buffer_lines(string, 0, Some(1)),
"sentence1\nsentence2",
);
assert_eq!(skip_buffer_lines(string, 0, Some(0)), "sentence1",);
assert_eq!(skip_buffer_lines(string, 1, Some(0)), "sentence2",);
}
}