using System.Collections.Immutable;
using System.Reflection;
using Connected.Annotations;
using Connected.Collections;

namespace Connected.Instance;

public static class Assemblies
{
	private static readonly List<Assembly> _all;
	static Assemblies()
	{
		_all = new();

		foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
		{
			if (assembly.GetCustomAttribute<MicroServiceAttribute>() is not null)
				_all.Add(assembly);
		}
	}

	internal static ImmutableList<Assembly> All => _all.ToImmutableList();
	public static Dictionary<Type, Type> QueryInterfaces<TAttribute>(this Assembly assembly) where TAttribute : Attribute
	{
		var result = new Dictionary<Type, Type>();

		foreach (var type in assembly.GetTypes())
		{
			if (type.IsAbstract || !type.IsClass)
				continue;

			var interfaces = type.GetInterfaces();

			foreach (var i in interfaces)
			{
				if (i.GetCustomAttribute<TAttribute>() is not null)
					result.Add(i, type);
			}
		}

		return result;
	}

	public static Dictionary<Type, Type> QueryImplementations<T>(this Assembly assembly)
	{
		var result = new Dictionary<Type, Type>();

		foreach (var type in assembly.GetTypes())
		{
			if (type.IsAbstract || !type.IsClass)
				continue;

			if (type.GetInterface(typeof(T).FullName) is null)
				continue;

			var interfaces = type.GetInterfaces();

			foreach (var i in interfaces)
			{
				if (i.GetInterface(typeof(T).FullName) is not null)
					result.Add(i, type);
			}
		}

		return result;
	}

	public static ImmutableList<Type> QueryImplementations<T>()
	{
		var target = typeof(T).FullName;
		var result = new List<Type>();

		foreach (var microService in _all)
		{
			var types = microService.GetTypes();

			foreach (var type in types)
			{
				if (type.IsAbstract || type.IsPrimitive || type.IsInterface)
					continue;

				if (type.GetInterface(target) is not null)
					result.Add(type);
			}
		}

		result.SortByPriority();

		return result.ToImmutableList();
	}

}