GodotComponentTest/entities/Chest.cs

using System.Linq;
using Godot;
using GodotComponentTest.components;
using GodotComponentTest.entities;

public class Chest : Entity, IInteractionInterface {
    // resources
    private readonly PackedScene _goldBarScene = GD.Load<PackedScene>("res://entities/GoldBar.tscn");

    public enum LidState {
        Closed,
        Open
    }

    public LidState State = LidState.Closed;
    public bool IsMouseOver;

    private MeshInstance _mesh;
    private AnimationPlayer _animationPlayer;

    public InteractionComponent InteractionComponent { get; set; }

    [Signal]
    private delegate void EntityClicked(Entity entity);

    [Signal]
    private delegate void ChestOpened(Entity entity);

    // Called when the node enters the scene tree for the first time.
    public override void _Ready() {
        _mesh = GetNode<MeshInstance>("Geometry/Skeleton/Chest");
        _animationPlayer = GetNode<AnimationPlayer>("AnimationPlayer");

        Connect("input_event", this, nameof(OnAreaInputEvent));
        Connect("mouse_entered", this, nameof(OnAreaMouseEntered));
        Connect("mouse_exited", this, nameof(OnAreaMouseExited));
        Connect("ChestOpened", this, nameof(ChestOpened));
    }


    public void OnAreaInputEvent(Node camera, InputEvent inputEvent, Vector3 position, Vector3 normal,
        int shapeIndex) {
        if (IsMouseOver && inputEvent is InputEventMouseButton) {
            InputEventMouseButton mouseButtonEvent = (InputEventMouseButton)inputEvent;
            if (mouseButtonEvent.ButtonIndex == 1 && mouseButtonEvent.Pressed) {
                EmitSignal("EntityClicked", this);
            }
        }
    }


    public void OnAreaMouseEntered() {
        IsMouseOver = true;
        SpatialMaterial overrideMaterial = new();
        overrideMaterial.AlbedoColor = new Color(1, 0, 0);
        _mesh.MaterialOverride = overrideMaterial;
    }


    public void OnAreaMouseExited() {
        IsMouseOver = false;
        _mesh.MaterialOverride = null;
    }


    public void OnInteractionStart() {
        _animationPlayer.Stop();

        if (State == LidState.Closed) {
            State = LidState.Open;
            _animationPlayer.Play("ChestOpen");
        } else {
            _animationPlayer.PlayBackwards("ChestOpen");
            State = LidState.Closed;
        }
    }


    public void OnInteractionEnd() { }

    public void OnChestOpened() {
        GD.Print("Chest now opened!");
        foreach (int i in Enumerable.Range(0, 10)) {
            GoldBar bar = (GoldBar)_goldBarScene.Instance();
            bar.Transform = new Transform(Transform.basis.Rotated(Vector3.Up, GD.Randf() * 2 * Mathf.Pi),
                Transform.origin + Vector3.Up * 0.8f);
            bar.velocity = new Vector3(
                (GD.Randf() * 2f - 1f) * 2,
                5 + GD.Randf() * 0.3f,
                (GD.Randf() * 2f - 1f) * 2
            );
            GetParent().AddChild(bar);
        }

        if (InteractionComponent != null) {
            InteractionComponent.EndInteraction();
        }
    }
}