1 files changed, 74 insertions, 0 deletions
diff --git a/src/scenes/mod.rs b/src/scenes/mod.rs
new file mode 100644
index 0000000..60db647
--- /dev/null
+++ b/src/scenes/mod.rs
@@ -0,0 +1,74 @@
+//! Scenes: the title screen, the name forge, and derelicts to board;
+//! flight and ports later.
+
+pub mod derelict;
+pub mod forge;
+pub mod title;
+
+use ratatui::Frame;
+use ratatui::crossterm::event::KeyEvent;
+
+use crate::app::Ctx;
+
+/// What a scene wants to happen after it handles a key or a tick.
+pub enum Transition {
+    None,
+    /// Open a scene on top of this one. Popping it comes back here.
+    Push(Box<dyn Scene>),
+    /// Close this scene and return to the one beneath it.
+    Pop,
+    Quit,
+}
+
+/// One screen of the game. The game keeps a stack of them; only the top one
+/// gets keys and ticks and is drawn.
+pub trait Scene {
+    /// A key was pressed, or auto-repeated while held.
+    fn key(&mut self, key: KeyEvent, ctx: &mut Ctx) -> Transition;
+
+    /// One fixed step of game time; there are `app::TICKS_PER_SECOND` of
+    /// these a second, whatever the frame rate. Turn-based scenes can ignore it.
+    fn tick(&mut self, _ctx: &mut Ctx) -> Transition {
+        Transition::None
+    }
+
+    fn render(&self, frame: &mut Frame, ctx: &Ctx);
+}
+
+#[cfg(test)]
+mod tests {
+    use ratatui::Terminal;
+    use ratatui::backend::TestBackend;
+    use ratatui::crossterm::event::{KeyCode, KeyModifiers};
+
+    use super::*;
+    use crate::term::KeyboardCaps;
+
+    pub fn test_ctx() -> Ctx {
+        Ctx::new(1, KeyboardCaps { key_release: false })
+    }
+
+    /// Draws every scene at several sizes, down to absurdly small ones, to
+    /// catch layout arithmetic that panics.
+    #[test]
+    fn scenes_render_at_any_size() {
+        let mut ctx = test_ctx();
+        let mut abandoning = derelict::Derelict::new(2);
+        abandoning.key(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE), &mut ctx);
+        let scenes: [Box<dyn Scene>; 4] = [
+            Box::new(title::Title::new(&ctx)),
+            Box::new(forge::Forge::new(&ctx)),
+            Box::new(derelict::Derelict::new(1)),
+            Box::new(abandoning),
+        ];
+        for (width, height) in [(160, 50), (80, 24), (40, 12), (5, 3), (1, 1)] {
+            let mut terminal = Terminal::new(TestBackend::new(width, height)).unwrap();
+            for scene in &scenes {
+                for ticks in [0, 12_345] {
+                    ctx.ticks = ticks;
+                    terminal.draw(|frame| scene.render(frame, &ctx)).unwrap();
+                }
+            }
+        }
+    }
+}