Add debug save states (#6)

Adds a one-slot in-memory debug save state. D-pad left stores the current single-player state and D-pad right restores it.

Reviewed-on: #6
Co-authored-by: Álex Román Núñez <eirexe@eirteam.moe>

src/debug_tools.rs

@@ -14,6 +14,8 @@ use enum_cycling_derive::EnumCycle;
 
 use crate::{AppState, player::Player, replay::StopReplayRecording};
 
+mod save_state;
+
 pub const PLAYER_DEBUG_ROW_COUNT: usize = 6;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Reflect)]
@@ -378,6 +380,9 @@ impl Plugin for DebugToolsPlugin {
     fn build(&self, app: &mut App) {
         app.init_resource::<DebugSettings>()
             .init_resource::<FrameStepState>()
+            .init_resource::<save_state::DebugSaveState>()
+            .add_systems(OnEnter(AppState::InMatch), save_state::clear)
+            .add_systems(OnExit(AppState::InMatch), save_state::clear)
             .add_systems(
                 PreUpdate,
                 prepare_frame_step
@@ -385,6 +390,13 @@ impl Plugin for DebugToolsPlugin {
                     .before(RunGgrsSystems)
                     .run_if(in_state(AppState::InMatch)),
             )
+            .add_systems(
+                PreUpdate,
+                save_state::save_or_restore
+                    .after(InputSystems)
+                    .before(RunGgrsSystems)
+                    .run_if(in_state(AppState::InMatch)),
+            )
             .add_systems(PreUpdate, restore_frame_step_time.after(RunGgrsSystems))
             .add_systems(
                 Update,