Implement 'quick access' via Alt-<n> (#79)

* Implement 'quick access' via numbers

Puts numbers 0-9 next to commands *above* current selection.
Ctrl-<number> should activate them - but since Ctrl-<num> are
reserved by terminal, this does not currently work. Need to
find different sets of keyboard shortcuts.

Numbers are *above* current selection, since the user must use
the arrow keys to go over the commands below current selection
before reaching selection.

* Use Alt+<n> to select last nth command

* Don't print Opt+0

Same as <Enter>

* Run rustfmt

* Simplify code

- Use ? operator for getting selected item
- Use RangeInclusive to check if character pressed is a number

src/command/search.rs

@@ -97,6 +97,23 @@ impl State {
                     ago = format!(" {}", ago);
                 }
 
+                let selected_index = match self.results_state.selected() {
+                    None => Span::raw("   "),
+                    Some(selected) => match i.checked_sub(selected) {
+                        None => Span::raw("   "),
+                        Some(diff) => {
+                            if 0 < diff && diff < 10 {
+                                Span::styled(
+                                    format!(" {} ", diff),
+                                    Style::default().fg(Color::DarkGray),
+                                )
+                            } else {
+                                Span::raw("   ")
+                            }
+                        }
+                    },
+                };
+
                 let duration = Span::styled(
                     duration,
                     Style::default().fg(if m.exit == 0 || m.duration == -1 {
@@ -115,8 +132,14 @@ impl State {
                     }
                 }
 
-                let spans =
-                    Spans::from(vec![duration, Span::raw(" "), ago, Span::raw(" "), command]);
+                let spans = Spans::from(vec![
+                    selected_index,
+                    duration,
+                    Span::raw(" "),
+                    ago,
+                    Span::raw(" "),
+                    command,
+                ]);
 
                 ListItem::new(spans)
             })
@@ -171,6 +194,16 @@ async fn key_handler(
                     .map_or(app.input.clone(), |h| h.command.clone()),
             );
         }
+        Key::Alt(c) if ('1'..='9').contains(&c) => {
+            let c = c.to_digit(10)? as usize;
+            let i = app.results_state.selected()? + c;
+
+            return Some(
+                app.results
+                    .get(i)
+                    .map_or(app.input.clone(), |h| h.command.clone()),
+            );
+        }
         Key::Char(c) => {
             app.input.push(c);
             query_results(app, search_mode, db).await.unwrap();