Initial work on rollback and refactor

src/fighter/state/wait.rs

@@ -0,0 +1,43 @@
+use bevy::prelude::*;
+
+use super::{FighterState, FighterStateContext, FighterStateTransition, ground, walk};
+use crate::fighter::{FighterAttributes, FighterVelocity};
+use crate::game_settings::GameSettings;
+
+#[derive(Component, Debug, Clone, Copy)]
+pub struct WaitState;
+
+impl FighterState for WaitState {
+    fn check_interrupt(
+        &self,
+        state_context: &FighterStateContext,
+    ) -> Option<FighterStateTransition> {
+        walk::check_input(state_context)
+    }
+}
+
+pub fn check_input(state_context: &FighterStateContext) -> Option<FighterStateTransition> {
+    let input_frame = state_context.input.get_last_frame();
+
+    if input_frame.movement.x.abs() < state_context.game_settings.input_common.stick_deadzone {
+        return Some(FighterStateTransition::Wait);
+    }
+    None
+}
+
+pub fn wait_update(
+    query: Query<(&FighterAttributes, &mut FighterVelocity), With<WaitState>>,
+    game_settings: Res<GameSettings>,
+) {
+    for (attribs, mut velocity) in query {
+        let friction = if velocity.x.abs() > attribs.max_walk_vel {
+            attribs.ground_friction
+                * game_settings
+                    .figher_common
+                    .ground_friction_over_walk_speed_multiplier
+        } else {
+            attribs.ground_friction
+        };
+        velocity.x += ground::apply_grounded_friction(friction, velocity.x);
+    }
+}