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
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
use crossterm::{
cursor::MoveTo,
event::{self, Event, KeyCode, KeyEvent, KeyEventKind, KeyModifiers},
execute,
style::Print,
terminal::{Clear, ClearType, disable_raw_mode, enable_raw_mode},
};
use rasteroid::image_extended::ZoomPanViewport;
use std::{
io::{self, Write},
time::Duration,
};
pub fn show_help_prompt(
out: &mut impl Write,
term_width: u16,
term_height: u16,
state: &ZoomPanViewport,
) -> io::Result<()> {
let help_text = "[Arrow/hjkl] Move [g/G] Start/End [+/-] Zoom [0] Reset [q/ESC] Quit";
let status_text = format!(
"Position: ({}, {}) | Zoom: {}x",
state.pan_x(),
state.pan_y(),
state.zoom()
);
// Calculate positions (bottom of screen)
let separator_line = 2; // Lines reserved for status/help
let status_line = term_height.saturating_sub(separator_line);
let help_line = term_height.saturating_sub(1);
// Center the text horizontally
let help_pos = term_width.saturating_sub(help_text.len() as u16) / 2;
let status_pos = term_width.saturating_sub(status_text.len() as u16) / 2;
// Add separator line
execute!(
out,
MoveTo(0, status_line.saturating_sub(1)),
Print(format!("{:━^width$}", "", width = term_width as usize)),
)?;
// Write status text
execute!(out, MoveTo(status_pos, status_line), Print(&status_text),)?;
// Write help text
execute!(out, MoveTo(help_pos, help_line), Print(&help_text),)?;
Ok(())
}
pub fn clear_screen(stdout: &mut impl std::io::Write) -> std::io::Result<()> {
execute!(stdout, Clear(ClearType::All), MoveTo(0, 0))?;
Ok(())
}
pub fn run_interactive_viewer(
container_width: u32,
container_height: u32,
image_width: u32,
image_height: u32,
mut callback: impl FnMut(&ZoomPanViewport) -> Option<()>,
) -> std::io::Result<()> {
enable_raw_mode()?;
let mut viewport =
ZoomPanViewport::new(container_width, container_height, image_width, image_height);
// Initial callback
let mut should_quit = callback(&viewport);
let mut last_callback_time = std::time::Instant::now();
let callback_throttle = std::time::Duration::from_millis(50);
while should_quit.is_some() {
if event::poll(Duration::from_millis(16))? {
// ~60fps
if let Event::Key(key) = event::read()? {
if key.kind == KeyEventKind::Release {
continue;
}
let mut clicked_correct_key = false;
match key {
// Quit (q or ESC)
KeyEvent {
code: KeyCode::Char('q'),
modifiers: KeyModifiers::NONE,
..
}
| KeyEvent {
code: KeyCode::Esc, ..
} => break,
//left
KeyEvent {
code: KeyCode::Left,
..
}
| KeyEvent {
code: KeyCode::Char('h'),
modifiers: KeyModifiers::NONE,
..
} => {
if viewport.adjust_pan(-50, 0) {
clicked_correct_key = true;
}
}
// right
KeyEvent {
code: KeyCode::Right,
modifiers: KeyModifiers::NONE,
..
}
| KeyEvent {
code: KeyCode::Char('l'),
modifiers: KeyModifiers::NONE,
..
} => {
if viewport.adjust_pan(50, 0) {
clicked_correct_key = true;
}
}
// up
KeyEvent {
code: KeyCode::Up,
modifiers: KeyModifiers::NONE,
..
}
| KeyEvent {
code: KeyCode::Char('k'),
modifiers: KeyModifiers::NONE,
..
} => {
if viewport.adjust_pan(0, -50) {
clicked_correct_key = true;
}
}
// down
KeyEvent {
code: KeyCode::Down,
modifiers: KeyModifiers::NONE,
..
}
| KeyEvent {
code: KeyCode::Char('j'),
modifiers: KeyModifiers::NONE,
..
} => {
if viewport.adjust_pan(0, 50) {
clicked_correct_key = true;
}
}
// stronger up
KeyEvent {
code: KeyCode::Char('u'),
modifiers: KeyModifiers::CONTROL,
..
} => {
if viewport.adjust_pan(0, -200) {
clicked_correct_key = true;
}
}
// stronger down
KeyEvent {
code: KeyCode::Char('d'),
modifiers: KeyModifiers::CONTROL,
..
} => {
if viewport.adjust_pan(0, 200) {
clicked_correct_key = true;
}
}
// Zoom (+, - or =)
KeyEvent {
code: KeyCode::Char('+'),
modifiers: KeyModifiers::NONE,
..
}
| KeyEvent {
code: KeyCode::Char('='),
modifiers: KeyModifiers::NONE,
..
} => {
clicked_correct_key = true;
viewport.set_zoom(viewport.zoom() + 1);
}
KeyEvent {
code: KeyCode::Char('-'),
modifiers: KeyModifiers::NONE,
..
} => {
if viewport.zoom() > 1 {
clicked_correct_key = true;
viewport.set_zoom(viewport.zoom() - 1);
}
}
KeyEvent {
code: KeyCode::Char('g'),
modifiers: KeyModifiers::NONE,
..
} => {
let (_, _, y, _) = viewport.get_pan_limits();
if viewport.pan_y() != y {
clicked_correct_key = true;
viewport.set_pan(viewport.pan_x(), y);
}
}
KeyEvent {
code: KeyCode::Char('G'),
modifiers: KeyModifiers::SHIFT,
..
} => {
let (_, _, _, y) = viewport.get_pan_limits();
if viewport.pan_y() != y {
clicked_correct_key = true;
viewport.set_pan(viewport.pan_x(), y);
}
}
// Reset (0)
KeyEvent {
code: KeyCode::Char('0'),
modifiers: KeyModifiers::NONE,
..
} => {
clicked_correct_key = true;
viewport.set_zoom(1);
viewport.set_pan(0, 0);
}
_ => {}
}
// Callback after each key press, but throttled
if clicked_correct_key {
let now = std::time::Instant::now();
if now.duration_since(last_callback_time) >= callback_throttle {
should_quit = callback(&viewport);
last_callback_time = now;
}
}
}
}
}
disable_raw_mode()?;
Ok(())
}