Add additional controls to text window

Adds PgUp, PgDown, Home and End as controls for the text window

CHANGELOG.md

@@ -9,6 +9,7 @@
 - Add collection ID/path to help modal ([#59](https://github.com/LucasPickering/slumber/issues/59))
   - Also add collection ID to terminal title
 - Persist UI state between sessions ([#39](https://github.com/LucasPickering/slumber/issues/39))
+- Text window can be controlled with PgUp/PgDown/Home/End ([#77](https://github.com/LucasPickering/slumber/issues/77))
 
 ### Changed
 
@@ -24,6 +25,7 @@
 ### Fixed
 
 - Don't require collection file to be present for `show` subcommand ([#62](https://github.com/LucasPickering/slumber/issues/62))
+- Fix state file being created in root Slumber directory if collection file is invalid ([#71](https://github.com/LucasPickering/slumber/issues/71))
 
 ## [0.9.0] - 2023-11-28
 

src/tui/input.rs

@@ -46,6 +46,10 @@ impl InputEngine {
                 InputBinding::new(KeyCode::Down, Action::Down).hide(),
                 InputBinding::new(KeyCode::Left, Action::Left).hide(),
                 InputBinding::new(KeyCode::Right, Action::Right).hide(),
+                InputBinding::new(KeyCode::PageUp, Action::PageUp).hide(),
+                InputBinding::new(KeyCode::PageDown, Action::PageDown).hide(),
+                InputBinding::new(KeyCode::Home, Action::Home).hide(),
+                InputBinding::new(KeyCode::End, Action::End).hide(),
                 InputBinding::new(KeyCode::Enter, Action::Submit),
                 InputBinding::new(KeyCode::Esc, Action::Cancel),
             ]
@@ -154,6 +158,10 @@ pub enum Action {
     Down,
     Left,
     Right,
+    PageUp,
+    PageDown,
+    Home,
+    End,
 
     /// Do a thing. E.g. select an item in a list
     Submit,

src/tui/view/common/text_window.rs

@@ -38,18 +38,26 @@ impl<T> TextWindow<T> {
         }
     }
 
+    /// Get the final line that we can't scroll past. This will be the first
+    /// line of the last page of text
+    fn max_scroll_line(&self) -> u16 {
+        self.text_height
+            .get()
+            .saturating_sub(self.window_height.get())
+    }
+
     fn scroll_up(&mut self, lines: u16) {
         self.offset_y = self.offset_y.saturating_sub(lines);
     }
 
     fn scroll_down(&mut self, lines: u16) {
-        self.offset_y = cmp::min(
-            self.offset_y + lines,
-            // Don't scroll past the bottom of the text
-            self.text_height
-                .get()
-                .saturating_sub(self.window_height.get()),
-        );
+        self.offset_y = cmp::min(self.offset_y + lines, self.max_scroll_line());
+    }
+
+    /// Scroll to a specific line number. The target line will end up as close
+    /// to the top of the page as possible
+    fn scroll_to(&mut self, line: u16) {
+        self.offset_y = cmp::min(line, self.max_scroll_line());
     }
 }
 
@@ -68,6 +76,22 @@ impl<T: Debug> EventHandler for TextWindow<T> {
                     self.scroll_down(1);
                     Update::Consumed
                 }
+                Action::PageUp => {
+                    self.scroll_up(self.window_height.get());
+                    Update::Consumed
+                }
+                Action::PageDown => {
+                    self.scroll_down(self.window_height.get());
+                    Update::Consumed
+                }
+                Action::Home => {
+                    self.scroll_to(0);
+                    Update::Consumed
+                }
+                Action::End => {
+                    self.scroll_to(u16::MAX);
+                    Update::Consumed
+                }
                 _ => Update::Propagate(event),
             },
             _ => Update::Propagate(event),
@@ -81,7 +105,6 @@ where
 {
     fn draw(&self, context: &mut DrawContext, _: (), area: Rect) {
         let text = self.text.generate();
-        // TODO how do we handle text longer than 65k lines?
         let text_height = text.lines.len() as u16;
         self.text_height.set(text_height);
         self.window_height.set(area.height);