refactor(show): split the key handler into grid, navigation and tool keys (S3776)

crates/ui-egui/src/show.rs

@@ -739,84 +739,19 @@ fn keyboard(ctx: &egui::Context, show: &mut Show, doc: &Presentation, now: f64,
     let mut keep = true;
     let mut actions = vec![];
     for (k, m) in keys {
-        use egui::Key::*;
-        let presenter_grid = presenter && show.presenter_grid;
-        let grid_open = if presenter { show.presenter_grid } else { show.grid };
-        if grid_open && !matches!(k, Escape | Minus) {
+        let handled = if grid_open(show, presenter) && !matches!(k, egui::Key::Escape | egui::Key::Minus) {
             // See All Slides takes no other keys until a slide is chosen.
-            if k == G && plain(m) {
-                if presenter_grid {
-                    show.presenter_grid = false;
-                } else {
-                    show.grid = false;
-                }
+            if k == egui::Key::G && plain(m) {
+                close_grid(show, presenter);
+                true
             } else {
-                continue;
+                false
             }
         } else {
-            match k {
-                Escape | Minus => {
-                    let cancelled = k == Escape && show.clear_goto();
-                    if !cancelled && !show.back_out(presenter) {
-                        keep = false;
-                    }
-                }
-                ArrowRight | ArrowDown | Space | PageDown | N => {
-                    if show.ended {
-                        keep = false;
-                    } else {
-                        actions.push(show.state.next(doc));
-                    }
-                }
-                Enter => {
-                    if !show.goto.is_empty() {
-                        if let Some(i) = show.take_goto()
-                            && i < doc.slides.len()
-                        {
-                            actions.push(show.state.goto(doc, i));
-                        }
-                    } else if show.ended {
-                        keep = false;
-                    } else {
-                        actions.push(show.state.next(doc));
-                    }
-                }
-                Backspace if !show.goto.is_empty() => {
-                    show.goto.pop();
-                }
-                ArrowLeft | ArrowUp | Backspace | PageUp | P if !(k == P && m.command) => {
-                    show.ended = false;
-                    actions.push(show.state.prev(doc));
-                }
-                P if m.command => show.set_pen(!show.pen),
-                L if m.command => show.set_laser(!show.laser),
-                A if m.command => show.arrow(),
-                Home => {
-                    if let Some(i) = show.state.first_index(doc) {
-                        actions.push(show.state.goto(doc, i));
-                    }
-                }
-                End => {
-                    if let Some(i) = show.state.last_index(doc) {
-                        actions.push(show.state.goto(doc, i));
-                    }
-                }
-                B | Period => toggle_blank(show, Color32::BLACK),
-                W | Comma => toggle_blank(show, Color32::WHITE),
-                E => show.strokes.clear(),
-                G if plain(m) => show.open_grid(presenter),
-                Z if plain(m) => show.zoom_key(),
-                T if plain(m) => show.timer.toggle(now),
-                R if plain(m) => show.timer.reset(now),
-                OpenBracket if plain(m) => show.nudge_notes(-NOTES_STEP),
-                CloseBracket if plain(m) => show.nudge_notes(NOTES_STEP),
-                Num0 | Num1 | Num2 | Num3 | Num4 | Num5 | Num6 | Num7 | Num8 | Num9 => {
-                    if let Some(d) = k.name().chars().next() {
-                        show.push_slide_number(d, now);
-                    }
-                }
-                _ => continue,
-            }
+            navigation_key(show, doc, k, m, presenter, &mut keep, &mut actions) || tool_key(show, k, m, now, presenter)
+        };
+        if !handled {
+            continue;
         }
         // The same key must not also activate a focused presenter button or be handled again
         // by an embedded presenter viewport.
@@ -831,6 +766,111 @@ fn keyboard(ctx: &egui::Context, show: &mut Show, doc: &Presentation, now: f64,
     keep
 }
 
+/// Whether the grid that the presenter key G opens is showing in this viewport.
+fn grid_open(show: &Show, presenter: bool) -> bool {
+    if presenter { show.presenter_grid } else { show.grid }
+}
+
+/// Closes the grid that G opens in this viewport.
+fn close_grid(show: &mut Show, presenter: bool) {
+    if presenter && show.presenter_grid {
+        show.presenter_grid = false;
+    } else {
+        show.grid = false;
+    }
+}
+
+/// Keys that move through the show or end it. False when `k` isn't one of them.
+fn navigation_key(
+    show: &mut Show,
+    doc: &Presentation,
+    k: egui::Key,
+    m: egui::Modifiers,
+    presenter: bool,
+    keep: &mut bool,
+    actions: &mut Vec<ShowAction>,
+) -> bool {
+    use egui::Key::*;
+    match k {
+        Escape | Minus => {
+            let cancelled = k == Escape && show.clear_goto();
+            if !cancelled && !show.back_out(presenter) {
+                *keep = false;
+            }
+        }
+        ArrowRight | ArrowDown | Space | PageDown | N => {
+            if show.ended {
+                *keep = false;
+            } else {
+                actions.push(show.state.next(doc));
+            }
+        }
+        Enter => {
+            if !show.goto.is_empty() {
+                if let Some(i) = show.take_goto()
+                    && i < doc.slides.len()
+                {
+                    actions.push(show.state.goto(doc, i));
+                }
+            } else if show.ended {
+                *keep = false;
+            } else {
+                actions.push(show.state.next(doc));
+            }
+        }
+        Backspace if !show.goto.is_empty() => {
+            show.goto.pop();
+        }
+        ArrowLeft | ArrowUp | Backspace | PageUp => {
+            show.ended = false;
+            actions.push(show.state.prev(doc));
+        }
+        P if m.command => show.set_pen(!show.pen),
+        P => {
+            show.ended = false;
+            actions.push(show.state.prev(doc));
+        }
+        Home => {
+            if let Some(i) = show.state.first_index(doc) {
+                actions.push(show.state.goto(doc, i));
+            }
+        }
+        End => {
+            if let Some(i) = show.state.last_index(doc) {
+                actions.push(show.state.goto(doc, i));
+            }
+        }
+        _ => return false,
+    }
+    true
+}
+
+/// Pen, laser, blanking, zoom, the timer, note size and typed slide numbers. False when `k`
+/// isn't one of them.
+fn tool_key(show: &mut Show, k: egui::Key, m: egui::Modifiers, now: f64, presenter: bool) -> bool {
+    use egui::Key::*;
+    match k {
+        L if m.command => show.set_laser(!show.laser),
+        A if m.command => show.arrow(),
+        B | Period => toggle_blank(show, Color32::BLACK),
+        W | Comma => toggle_blank(show, Color32::WHITE),
+        E => show.strokes.clear(),
+        G if plain(m) => show.open_grid(presenter),
+        Z if plain(m) => show.zoom_key(),
+        T if plain(m) => show.timer.toggle(now),
+        R if plain(m) => show.timer.reset(now),
+        OpenBracket if plain(m) => show.nudge_notes(-NOTES_STEP),
+        CloseBracket if plain(m) => show.nudge_notes(NOTES_STEP),
+        Num0 | Num1 | Num2 | Num3 | Num4 | Num5 | Num6 | Num7 | Num8 | Num9 => {
+            if let Some(d) = k.name().chars().next() {
+                show.push_slide_number(d, now);
+            }
+        }
+        _ => return false,
+    }
+    true
+}
+
 /// Draw and advance the active show, handling hidden frames, timing, input, transitions, and
 /// presenter/reading presentation.
 pub fn ui(app: &mut SlideApp, ui: &mut Ui) {