added basic action system

bdi_game/src/display/actions.rs

@@ -0,0 +1,82 @@
+use crate::simulation::grid;
+use sdl2::event::Event;
+use sdl2::keyboard::Keycode;
+use sdl2::mouse::MouseButton;
+use sdl2::{EventPump, Sdl};
+use std::collections::VecDeque;
+use std::collections::vec_deque::{IterMut, Iter};
+
+pub enum Action {
+    ClickGridCell(grid::GridPoint),
+    QuitGame(),
+}
+
+impl Action {
+    pub fn check_click_grid_cell(x: i32, y: i32) -> Option<Self> {
+        todo!()
+    }
+}
+
+pub struct ActionPump {
+    sdl_pump: EventPump,
+    actions: VecDeque<Action>,
+}
+
+impl ActionPump {
+    pub fn new(sdl_context: Sdl) -> Self {
+        Self {
+            sdl_pump: sdl_context.event_pump().expect("Failed to initialize SDL Event Pump."),
+            actions: VecDeque::new(),
+        }
+    }
+
+    pub fn poll_action(&mut self) -> Option<Action> {
+        self.actions.pop_front()
+    }
+
+    pub fn poll_iter(&mut self) -> Iter<'_, Action> {
+        self.actions.iter()
+    }
+
+    pub fn poll_iter_mut(&mut self) -> IterMut<'_, Action> {
+        self.actions.iter_mut()
+    }
+
+    fn pump_actions(&mut self) {
+        for sdl_ev in self.sdl_pump.poll_iter() {
+            let action = Self::match_input(sdl_ev);
+            if let Some(action) = action {
+                self.actions.push_back(action)
+            }
+        }
+    }
+
+    fn match_input(sdl_ev: Event) -> Option<Action> {
+        match sdl_ev {
+            Event::KeyDown { keycode, .. } => {
+                Self::match_key_down(keycode.unwrap())
+            },
+
+            Event::MouseButtonDown { mouse_btn, x, y, .. } => {
+                Self::match_button_down(mouse_btn, x, y)
+            },
+
+            _ => None,
+        }
+    }
+
+    fn match_key_down(key: Keycode) -> Option<Action> {
+        match key {
+            Keycode::Escape => Some(Action::QuitGame()),
+            _ => None,
+        }
+    }
+
+    fn match_button_down(button: MouseButton, x: i32, y: i32) -> Option<Action> {
+        match button {
+            MouseButton::Left => Action::check_click_grid_cell(x, y), 
+            _ => None,
+        }
+    }
+
+}

bdi_game/src/display/mod.rs

@@ -1,2 +1,3 @@
 pub mod game_display;
 pub mod sdl_display;
+pub mod actions;