1use anyhow::anyhow;
2use serde::Deserialize;
3use smallvec::SmallVec;
4use std::fmt::Write;
5
6/// A keystroke and associated metadata generated by the platform
7#[derive(Clone, Debug, Eq, PartialEq, Default, Deserialize, Hash)]
8pub struct Keystroke {
9 /// the state of the modifier keys at the time the keystroke was generated
10 pub modifiers: Modifiers,
11
12 /// key is the character printed on the key that was pressed
13 /// e.g. for option-s, key is "s"
14 pub key: String,
15
16 /// ime_key is the character inserted by the IME engine when that key was pressed.
17 /// e.g. for option-s, ime_key is "ß"
18 pub ime_key: Option<String>,
19}
20
21impl Keystroke {
22 /// When matching a key we cannot know whether the user intended to type
23 /// the ime_key or the key itself. On some non-US keyboards keys we use in our
24 /// bindings are behind option (for example `$` is typed `alt-ç` on a Czech keyboard),
25 /// and on some keyboards the IME handler converts a sequence of keys into a
26 /// specific character (for example `"` is typed as `" space` on a brazilian keyboard).
27 ///
28 /// This method generates a list of potential keystroke candidates that could be matched
29 /// against when resolving a keybinding.
30 pub(crate) fn match_candidates(&self) -> SmallVec<[Keystroke; 2]> {
31 let mut possibilities = SmallVec::new();
32 match self.ime_key.as_ref() {
33 Some(ime_key) => {
34 if ime_key != &self.key {
35 possibilities.push(Keystroke {
36 modifiers: Modifiers {
37 control: self.modifiers.control,
38 alt: false,
39 shift: false,
40 command: false,
41 function: false,
42 },
43 key: ime_key.to_string(),
44 ime_key: None,
45 });
46 }
47 possibilities.push(Keystroke {
48 ime_key: None,
49 ..self.clone()
50 });
51 }
52 None => possibilities.push(self.clone()),
53 }
54 possibilities
55 }
56
57 /// key syntax is:
58 /// [ctrl-][alt-][shift-][cmd-][fn-]key[->ime_key]
59 /// ime_key syntax is only used for generating test events,
60 /// when matching a key with an ime_key set will be matched without it.
61 pub fn parse(source: &str) -> anyhow::Result<Self> {
62 let mut control = false;
63 let mut alt = false;
64 let mut shift = false;
65 let mut command = false;
66 let mut function = false;
67 let mut key = None;
68 let mut ime_key = None;
69
70 let mut components = source.split('-').peekable();
71 while let Some(component) = components.next() {
72 match component {
73 "ctrl" => control = true,
74 "alt" => alt = true,
75 "shift" => shift = true,
76 "cmd" => command = true,
77 "fn" => function = true,
78 _ => {
79 if let Some(next) = components.peek() {
80 if next.is_empty() && source.ends_with('-') {
81 key = Some(String::from("-"));
82 break;
83 } else if next.len() > 1 && next.starts_with('>') {
84 key = Some(String::from(component));
85 ime_key = Some(String::from(&next[1..]));
86 components.next();
87 } else {
88 return Err(anyhow!("Invalid keystroke `{}`", source));
89 }
90 } else {
91 key = Some(String::from(component));
92 }
93 }
94 }
95 }
96
97 let key = key.ok_or_else(|| anyhow!("Invalid keystroke `{}`", source))?;
98
99 Ok(Keystroke {
100 modifiers: Modifiers {
101 control,
102 alt,
103 shift,
104 command,
105 function,
106 },
107 key,
108 ime_key,
109 })
110 }
111
112 /// Returns a new keystroke with the ime_key filled.
113 /// This is used for dispatch_keystroke where we want users to
114 /// be able to simulate typing "space", etc.
115 pub fn with_simulated_ime(mut self) -> Self {
116 if self.ime_key.is_none()
117 && !self.modifiers.command
118 && !self.modifiers.control
119 && !self.modifiers.function
120 && !self.modifiers.alt
121 {
122 self.ime_key = match self.key.as_str() {
123 "space" => Some(" ".into()),
124 "tab" => Some("\t".into()),
125 "enter" => Some("\n".into()),
126 "up" | "down" | "left" | "right" | "pageup" | "pagedown" | "home" | "end"
127 | "delete" | "escape" | "backspace" | "f1" | "f2" | "f3" | "f4" | "f5" | "f6"
128 | "f7" | "f8" | "f9" | "f10" | "f11" | "f12" => None,
129 key => {
130 if self.modifiers.shift {
131 Some(key.to_uppercase())
132 } else {
133 Some(key.into())
134 }
135 }
136 }
137 }
138 self
139 }
140}
141
142impl std::fmt::Display for Keystroke {
143 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
144 if self.modifiers.control {
145 f.write_char('^')?;
146 }
147 if self.modifiers.alt {
148 f.write_char('⌥')?;
149 }
150 if self.modifiers.command {
151 f.write_char('⌘')?;
152 }
153 if self.modifiers.shift {
154 f.write_char('⇧')?;
155 }
156 let key = match self.key.as_str() {
157 "backspace" => '⌫',
158 "up" => '↑',
159 "down" => '↓',
160 "left" => '←',
161 "right" => '→',
162 "tab" => '⇥',
163 "escape" => '⎋',
164 key => {
165 if key.len() == 1 {
166 key.chars().next().unwrap().to_ascii_uppercase()
167 } else {
168 return f.write_str(key);
169 }
170 }
171 };
172 f.write_char(key)
173 }
174}
175
176/// The state of the modifier keys at some point in time
177#[derive(Copy, Clone, Debug, Eq, PartialEq, Default, Deserialize, Hash)]
178pub struct Modifiers {
179 /// The control key
180 pub control: bool,
181
182 /// The alt key
183 /// Sometimes also known as the 'meta' key
184 pub alt: bool,
185
186 /// The shift key
187 pub shift: bool,
188
189 /// The command key, on macos
190 /// the windows key, on windows
191 pub command: bool,
192
193 /// The function key
194 pub function: bool,
195}
196
197impl Modifiers {
198 /// Returns true if any modifier key is pressed
199 pub fn modified(&self) -> bool {
200 self.control || self.alt || self.shift || self.command || self.function
201 }
202
203 /// helper method for Modifiers with no modifiers
204 pub fn none() -> Modifiers {
205 Default::default()
206 }
207
208 /// helper method for Modifiers with just command
209 pub fn command() -> Modifiers {
210 Modifiers {
211 command: true,
212 ..Default::default()
213 }
214 }
215
216 /// helper method for Modifiers with just shift
217 pub fn shift() -> Modifiers {
218 Modifiers {
219 shift: true,
220 ..Default::default()
221 }
222 }
223
224 /// helper method for Modifiers with command + shift
225 pub fn command_shift() -> Modifiers {
226 Modifiers {
227 shift: true,
228 command: true,
229 ..Default::default()
230 }
231 }
232}