Files
Pacore/Assets/Pacore/Runtime/ClassAttributeCache.cs
2026-01-24 20:00:17 +00:00

67 lines
2.5 KiB
C#

using System.Collections.ObjectModel;
using System.Collections.Generic;
using System.Reflection;
using System.Linq;
using System;
using UnityEngine;
namespace PashaBibko.Pacore
{
public static class ClassAttributeCache
{
private static Dictionary<Type, List<Type>> AttributeCache { get; set; }
public static ReadOnlyCollection<Type> GetAttributesOf<T>()
{
return AttributeCache.TryGetValue(typeof(T), out List<Type> classes) ?
classes.AsReadOnly() :
throw new ArgumentException($"Attribute [{nameof(T)}] is not used by any classes");
}
[RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.AfterAssembliesLoaded)]
private static void ScanAllAssemblies()
{
/* Fetches all the class types in all loaded assemblies */
Type[] classes = AppDomain.CurrentDomain.GetAssemblies() // Assembly[]
.SelectMany(assembly =>
{
try
{
return assembly.GetTypes();
}
catch (ReflectionTypeLoadException err)
{
return err.Types.Where(t => t != null);
}
}) // IEnumerable<Type>
.Where(type => type.IsClass && !type.IsAbstract) // IEnumerable<Type>
.ToArray();
/* Allocates space for the cache */
AttributeCache = classes // Type[]
.Where(type => typeof(Attribute).IsAssignableFrom(type)) // IEnumerable<Type>
.ToDictionary
(
keySelector: t => t,
elementSelector: _ => new List<Type>()
); // Dictionary<Type, List<Type>>
/* Finds which attributes are attached to what classes */
foreach (Type current in classes)
{
/* Finds all the attributes of the current class */
Type[] attached = current // Type
.GetCustomAttributes(inherit: true) // object[]
.Select(attribute => attribute.GetType()) // IEnumerable<Type>
.Distinct().ToArray();
/* Adds the class type to each attribute in the dictionary */
foreach (Type attribute in attached)
{
AttributeCache[attribute].Add(current);
}
}
}
}
}