Small hand rework, simplest cards shuffle

src/card/mod.rs

@@ -1,3 +1,5 @@
+use std::f32;
+
 use crate::animation::transform::AnimatedTransform;
 use bevy::prelude::*;
 use drag::*;
@@ -10,7 +12,10 @@ pub struct CardPlugin;
 pub struct Card;
 
 #[derive(Component)]
-pub struct Hand;
+pub struct CardInHand;
+
+#[derive(Component)]
+pub struct Hand(Vec<Entity>);
 
 #[derive(Resource)]
 pub struct CardImage(Handle<Image>);
@@ -18,6 +23,9 @@ pub struct CardImage(Handle<Image>);
 #[derive(Event)]
 pub struct AddCard;
 
+#[derive(EntityEvent)]
+pub struct InsertCard(Entity);
+
 #[derive(Event)]
 pub struct ClearCards;
 
@@ -26,7 +34,8 @@ impl Plugin for CardPlugin {
         app.add_systems(Startup, hand_setup)
             .add_systems(Update, card_arrange)
             .add_observer(card_add)
-            .add_observer(card_clear);
+            .add_observer(card_clear)
+            .add_observer(insert_card);
         app.insert_resource(MousePosition(Vec3::new(0., 0., 0.)))
             .add_systems(PreUpdate, mouse_position_system)
             .add_observer(card_drag_start)
@@ -37,7 +46,7 @@ impl Plugin for CardPlugin {
 
 fn hand_setup(mut commands: Commands, asset_server: Res<AssetServer>) {
     commands.spawn((
-        Hand,
+        Hand(Vec::new()),
         Transform::from_xyz(0., -360., 0.),
         InheritedVisibility::VISIBLE,
     ));
@@ -48,41 +57,79 @@ fn hand_setup(mut commands: Commands, asset_server: Res<AssetServer>) {
 }
 
 fn card_arrange(
-    mut query: Query<(&mut AnimatedTransform, &Sprite), With<Card>>,
-    hand: Single<(Entity, &Children), With<Hand>>,
+    mut query: Query<(&mut AnimatedTransform, &Sprite), With<CardInHand>>,
+    hand: Single<(Entity, &Hand, &Transform)>,
     assets: Res<Assets<Image>>,
 ) {
-    let cards_amount = hand.1.len();
-    for (index, card) in hand.1.iter().enumerate() {
-        let Ok((mut transform, sprite)) = query.get_mut(card) else {
+    let cards_amount = hand.1.0.len();
+    for (index, card) in hand.1.0.iter().enumerate() {
+        let Ok((mut transform, sprite)) = query.get_mut(card.clone()) else {
             continue;
         };
         let size = assets.get(&sprite.image).unwrap().size_f32();
         let left_boundary = -size.x * (cards_amount as f32) / 2.0 + size.x / 2.0;
-        transform.translation.x = left_boundary + size.x * index as f32;
-        transform.translation.y = size.y / 2.0;
+        transform.translation.x = left_boundary + size.x * index as f32 + hand.2.translation.x;
+        transform.translation.y = size.y / 2.0 + hand.2.translation.y;
     }
 }
 
 fn card_add(
     _: On<AddCard>,
     mut commands: Commands,
-    hand: Single<Entity, With<Hand>>,
     card_image: Res<CardImage>,
+    mut hand: Single<&mut Hand>,
 ) {
-    commands.spawn((
-        Sprite::from_image(card_image.0.clone()),
-        Transform::from_xyz(0., 0., 0.),
-        AnimatedTransform::from_xyz(0., 0., 0.),
-        Card,
-        ChildOf(hand.entity()),
-        DraggableCard,
-        Pickable::default(),
-    ));
+    let card = commands
+        .spawn((
+            Sprite::from_image(card_image.0.clone()),
+            Transform::from_xyz(0., 0., 0.),
+            AnimatedTransform::from_xyz(0., 0., 0.),
+            Card,
+            DraggableCard,
+            CardInHand,
+            Pickable::default(),
+        ))
+        .id();
+
+    hand.0.push(card);
 }
 
-fn card_clear(_: On<ClearCards>, mut commands: Commands, children: Single<&Children, With<Hand>>) {
-    for card in children.iter() {
-        commands.entity(card).despawn();
+fn card_clear(_: On<ClearCards>, mut commands: Commands, mut hand: Single<&mut Hand>) {
+    for card in &hand.0 {
+        let entity = card.clone();
+        commands.entity(entity).despawn();
     }
+    hand.0.clear();
+}
+
+fn insert_card(
+    event: On<InsertCard>,
+    mut hand_query: Single<(Entity, &mut Hand)>,
+    transform_query: Query<&Transform, With<Card>>,
+) {
+    let Ok(inserted_transform) = transform_query.get(event.0) else {
+        return;
+    };
+
+    let mut decided_index: usize = 0;
+    let mut decided_diff: f32 = f32::INFINITY;
+
+    for (index, card) in hand_query.1.0.iter().enumerate() {
+        let Ok(card_transform) = transform_query.get(card.clone()) else {
+            continue;
+        };
+
+        let calculated_diff =
+            (inserted_transform.translation - card_transform.translation).length();
+
+        if decided_diff > calculated_diff {
+            decided_diff = calculated_diff;
+            decided_index = index;
+        }
+    }
+
+    if let Some(pos) = hand_query.1.0.iter().position(|ent| *ent == event.0) {
+        hand_query.1.0.remove(pos);
+    }
+    hand_query.1.0.insert(decided_index, event.0);
 }