CollisionProfileRegistry.cs

using Newtonsoft.Json;
 
namespace Gondwana.Physics.Collisions;

public sealed class CollisionProfileRegistry
{
    [JsonProperty("profiles")]
    private readonly Dictionary<string, CollisionProfile> _profiles;

    public CollisionProfileRegistry()
    {
        _profiles = new Dictionary<string, CollisionProfile>(StringComparer.OrdinalIgnoreCase);
        EnsureStandardProfiles();
    }
 
#pragma warning disable IDE0051 // Used by Newtonsoft.Json via reflection.
    [JsonConstructor]
    private CollisionProfileRegistry(Dictionary<string, CollisionProfile>? profiles)
    {
        _profiles = new Dictionary<string, CollisionProfile>(
            profiles ?? new Dictionary<string, CollisionProfile>(),
            StringComparer.OrdinalIgnoreCase);
 
        EnsureStandardProfiles();
    }
 
#pragma warning restore IDE0051

    public CollisionProfile Define(
        string name,
        string collisionGroup,
        IEnumerable<string>? collidesWith = null,
        bool collidesWithAll = false)
    {
        var profile = new CollisionProfile(
            name,
            collisionGroup,
            collidesWith,
            collidesWithAll);
 
        _profiles[name] = profile;
        return profile;
    }

    public CollisionProfile Get(string name)
    {
        if (string.IsNullOrWhiteSpace(name))
            throw new ArgumentException("Collision profile name cannot be empty.", nameof(name));
 
        if (!_profiles.TryGetValue(name, out var profile))
            throw new KeyNotFoundException($"Collision profile '{name}' is not defined.");
 
        return profile;
    }

    public bool TryGet(string name, out CollisionProfile? profile)
    {
        if (string.IsNullOrWhiteSpace(name))
        {
            profile = null;
            return false;
        }
 
        return _profiles.TryGetValue(name, out profile);
    }

    public IReadOnlyCollection<string> GetProfileNames() => _profiles.Keys.ToArray();
 
    private void EnsureStandardProfiles()
    {
        DefineIfMissing(
            CollisionProfileNames.World,
            "WorldStatic",
            ["Actors", "Projectiles"]);
 
        DefineIfMissing(
            CollisionProfileNames.Actor,
            "Actors",
            ["WorldStatic", "Actors", "Projectiles", "Triggers"]);
 
        DefineIfMissing(
            CollisionProfileNames.Projectile,
            "Projectiles",
            ["WorldStatic", "Actors"]);
 
        DefineIfMissing(
            CollisionProfileNames.Sensor,
            "Triggers",
            ["Actors"]);
    }
 
    private void DefineIfMissing(
        string name,
        string collisionGroup,
        IEnumerable<string> collidesWith)
    {
        if (!_profiles.ContainsKey(name))
            Define(name, collisionGroup, collidesWith);
    }
}