using System;

namespace Cryville.Common {
	public struct Identifier : IEquatable<Identifier> {
		public static Identifier Empty = new(0);
		public int Key { get; private set; }
		public readonly object Name => IdentifierManager.Shared.Retrieve(Key);
		public Identifier(int key) {
			Key = key;
		}
		public Identifier(object name) {
			Key = IdentifierManager.Shared.Request(name);
		}
		public override readonly bool Equals(object obj) {
			if (obj == null || obj is not Identifier other) return false;
			return Equals(other);
		}
		public readonly bool Equals(Identifier other) {
			return Key == other.Key;
		}
		public override readonly int GetHashCode() {
			return Key;
		}
		public override readonly string ToString() {
			if (Key == 0) return "";
			return Name.ToString();
		}
		public static bool operator ==(Identifier lhs, Identifier rhs) {
			return lhs.Equals(rhs);
		}
		public static bool operator !=(Identifier lhs, Identifier rhs) {
			return !lhs.Equals(rhs);
		}
	}
}