1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
use crate::{backend::Backend, buffer::Cell};
use crossterm::{
cursor::{CursorShape, Hide, MoveTo, SetCursorShape, Show},
execute, queue,
style::{
Attribute as CAttribute, Color as CColor, Print, SetAttribute, SetBackgroundColor,
SetForegroundColor, SetUnderlineColor,
},
terminal::{self, Clear, ClearType},
};
use helix_view::graphics::{Color, CursorKind, Modifier, Rect};
use std::io::{self, Write};
pub struct CrosstermBackend<W: Write> {
buffer: W,
}
impl<W> CrosstermBackend<W>
where
W: Write,
{
pub fn new(buffer: W) -> CrosstermBackend<W> {
CrosstermBackend { buffer }
}
}
impl<W> Write for CrosstermBackend<W>
where
W: Write,
{
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.buffer.write(buf)
}
fn flush(&mut self) -> io::Result<()> {
self.buffer.flush()
}
}
impl<W> Backend for CrosstermBackend<W>
where
W: Write,
{
fn draw<'a, I>(&mut self, content: I) -> io::Result<()>
where
I: Iterator<Item = (u16, u16, &'a Cell)>,
{
let mut fg = Color::Reset;
let mut bg = Color::Reset;
let mut underline = Color::Reset;
let mut modifier = Modifier::empty();
let mut last_pos: Option<(u16, u16)> = None;
for (x, y, cell) in content {
// Move the cursor if the previous location was not (x - 1, y)
if !matches!(last_pos, Some(p) if x == p.0 + 1 && y == p.1) {
map_error(queue!(self.buffer, MoveTo(x, y)))?;
}
last_pos = Some((x, y));
if cell.modifier != modifier {
let diff = ModifierDiff {
from: modifier,
to: cell.modifier,
};
diff.queue(&mut self.buffer)?;
modifier = cell.modifier;
}
if cell.fg != fg {
let color = CColor::from(cell.fg);
map_error(queue!(self.buffer, SetForegroundColor(color)))?;
fg = cell.fg;
}
if cell.bg != bg {
let color = CColor::from(cell.bg);
map_error(queue!(self.buffer, SetBackgroundColor(color)))?;
bg = cell.bg;
}
if cell.underline != underline {
let color = CColor::from(cell.underline);
map_error(queue!(self.buffer, SetUnderlineColor(color)))?;
underline = cell.underline;
}
map_error(queue!(self.buffer, Print(&cell.symbol)))?;
}
map_error(queue!(
self.buffer,
SetForegroundColor(CColor::Reset),
SetBackgroundColor(CColor::Reset),
SetAttribute(CAttribute::Reset)
))
}
fn hide_cursor(&mut self) -> io::Result<()> {
map_error(execute!(self.buffer, Hide))
}
fn show_cursor(&mut self, kind: CursorKind) -> io::Result<()> {
let shape = match kind {
CursorKind::Block => CursorShape::Block,
CursorKind::Bar => CursorShape::Line,
CursorKind::Underline => CursorShape::UnderScore,
CursorKind::Hidden => unreachable!(),
};
map_error(execute!(self.buffer, Show, SetCursorShape(shape)))
}
fn get_cursor(&mut self) -> io::Result<(u16, u16)> {
crossterm::cursor::position()
.map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))
}
fn set_cursor(&mut self, x: u16, y: u16) -> io::Result<()> {
map_error(execute!(self.buffer, MoveTo(x, y)))
}
fn clear(&mut self) -> io::Result<()> {
map_error(execute!(self.buffer, Clear(ClearType::All)))
}
fn size(&self) -> io::Result<Rect> {
let (width, height) =
terminal::size().map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?;
Ok(Rect::new(0, 0, width, height))
}
fn flush(&mut self) -> io::Result<()> {
self.buffer.flush()
}
}
fn map_error(error: crossterm::Result<()>) -> io::Result<()> {
error.map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))
}
#[derive(Debug)]
struct ModifierDiff {
pub from: Modifier,
pub to: Modifier,
}
impl ModifierDiff {
fn queue<W>(&self, mut w: W) -> io::Result<()>
where
W: io::Write,
{
//use crossterm::Attribute;
let removed = self.from - self.to;
if removed.contains(Modifier::REVERSED) {
map_error(queue!(w, SetAttribute(CAttribute::NoReverse)))?;
}
if removed.contains(Modifier::BOLD) {
map_error(queue!(w, SetAttribute(CAttribute::NormalIntensity)))?;
if self.to.contains(Modifier::DIM) {
map_error(queue!(w, SetAttribute(CAttribute::Dim)))?;
}
}
if removed.contains(Modifier::ITALIC) {
map_error(queue!(w, SetAttribute(CAttribute::NoItalic)))?;
}
if removed.intersects(Modifier::ANY_UNDERLINE) {
map_error(queue!(w, SetAttribute(CAttribute::NoUnderline)))?;
}
if removed.contains(Modifier::DIM) {
map_error(queue!(w, SetAttribute(CAttribute::NormalIntensity)))?;
}
if removed.contains(Modifier::CROSSED_OUT) {
map_error(queue!(w, SetAttribute(CAttribute::NotCrossedOut)))?;
}
if removed.contains(Modifier::SLOW_BLINK) || removed.contains(Modifier::RAPID_BLINK) {
map_error(queue!(w, SetAttribute(CAttribute::NoBlink)))?;
}
let added = self.to - self.from;
if added.contains(Modifier::REVERSED) {
map_error(queue!(w, SetAttribute(CAttribute::Reverse)))?;
}
if added.contains(Modifier::BOLD) {
map_error(queue!(w, SetAttribute(CAttribute::Bold)))?;
}
if added.contains(Modifier::ITALIC) {
map_error(queue!(w, SetAttribute(CAttribute::Italic)))?;
}
if added.contains(Modifier::UNDERLINED) {
map_error(queue!(w, SetAttribute(CAttribute::Underlined)))?;
}
if added.contains(Modifier::UNDERCURLED) {
map_error(queue!(w, SetAttribute(CAttribute::Undercurled)))?;
}
if added.contains(Modifier::UNDERDOTTED) {
map_error(queue!(w, SetAttribute(CAttribute::Underdotted)))?;
}
if added.contains(Modifier::UNDERDASHED) {
map_error(queue!(w, SetAttribute(CAttribute::Underdashed)))?;
}
if added.contains(Modifier::DOUBLE_UNDERLINED) {
map_error(queue!(w, SetAttribute(CAttribute::DoubleUnderlined)))?;
}
if added.contains(Modifier::DIM) {
map_error(queue!(w, SetAttribute(CAttribute::Dim)))?;
}
if added.contains(Modifier::CROSSED_OUT) {
map_error(queue!(w, SetAttribute(CAttribute::CrossedOut)))?;
}
if added.contains(Modifier::SLOW_BLINK) {
map_error(queue!(w, SetAttribute(CAttribute::SlowBlink)))?;
}
if added.contains(Modifier::RAPID_BLINK) {
map_error(queue!(w, SetAttribute(CAttribute::RapidBlink)))?;
}
Ok(())
}
}
|