ui.rs: Eliminate Runtime, draw Widget to frame

1 files changed, 27 insertions, 39 deletions

diff --git a/src/main/rust/ui.rs b/src/main/rust/ui.rs
index 5f2c603..daf00d4 100644
--- a/src/main/rust/ui.rs
+++ b/src/main/rust/ui.rs
@@ -1,68 +1,56 @@
 use crate::app::App;
 use ratatui::{
     Frame,
-    buffer::Buffer,
-    layout::Rect,
     style::Stylize,
     symbols::border,
     text::{Line, Text},
     widgets::{Block, Paragraph, Widget},
 };
 
-/// Explicitly declare lifetime as App is a reference;
-/// Runtime is only instantiated for render
-struct Runtime<'a> {
-    app: &'a App,
-}
-
 pub fn draw(frame: &mut Frame, app: &App) {
-    let run = Runtime { app };
-    frame.render_widget(&run, frame.area());
+    let rect = draw_layout(app);
+    frame.render_widget(rect, frame.area());
 }
 
-impl<'a> Widget for &Runtime<'a> {
-    fn render(self, area: Rect, buf: &mut Buffer) {
-        let title = Line::from(" Counter App Tutorial ".bold());
-        let instructions = Line::from(vec![
-            " Decrement ".into(),
-            "<Left>".blue().bold(),
-            " Increment ".into(),
-            "<Right>".blue().bold(),
-            " Quit ".into(),
-            "<Q> ".blue().bold(),
-        ]);
-        let block = Block::bordered()
-            .title(title.centered())
-            .title_bottom(instructions.centered())
-            .border_set(border::THICK);
+fn draw_layout(app: &App) -> impl Widget {
+    let title = Line::from(" Counter App Tutorial ".bold());
+    let instructions = Line::from(vec![
+        " Decrement ".into(),
+        "<Left>".blue().bold(),
+        " Increment ".into(),
+        "<Right>".blue().bold(),
+        " Quit ".into(),
+        "<Q> ".blue().bold(),
+    ]);
+    let block = Block::bordered()
+        .title(title.centered())
+        .title_bottom(instructions.centered())
+        .border_set(border::THICK);
 
-        let counter_text = Text::from(vec![Line::from(vec![
-            "Value: ".into(),
-            self.app.display_counter().yellow(),
-        ])]);
+    let counter_text = Text::from(vec![Line::from(vec![
+        "Value: ".into(),
+        app.display_counter().yellow(),
+    ])]);
 
-        Paragraph::new(counter_text)
-            .centered()
-            .block(block)
-            .render(area, buf);
-    }
+    Paragraph::new(counter_text).centered().block(block)
 }
 
 #[cfg(test)]
 mod tests {
 
     use super::*;
-    use ratatui::style::Style;
+    use ratatui::{buffer::Buffer, layout::Rect, style::Style};
 
     #[test]
-    fn render() {
+    fn render_success() {
         let mut app = App::default();
         assert!(app.init_context().is_ok());
-        let runtime = Runtime { app: &app };
 
-        let mut buf = Buffer::empty(Rect::new(0, 0, 50, 4));
+        let rect = Rect::new(0, 0, 50, 4);
+        let mut buf = Buffer::empty(rect);
 
-        runtime.render(buf.area, &mut buf);
+        let res = draw_layout(&app);
+        res.render(rect, &mut buf);
 
         let mut expected = Buffer::with_lines(vec![
             "┏━━━━━━━━━━━━━ Counter App Tutorial ━━━━━━━━━━━━━┓",