using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using Microsoft.Extensions.DependencyInjection;

namespace BITKit.Entities
{
    public class Entity : IEntity, IDisposable
    {
        public Entity()
        {
            ServiceCollection.AddSingleton<IEntity>(this);
        }
        public void WaitForInitializationComplete()
        {
            throw new NotImplementedException();
        }
        public int Id { get; set; } = Guid.NewGuid().GetHashCode();
        public CancellationToken CancellationToken => _cancellationTokenSource.Token;
        private readonly CancellationTokenSource _cancellationTokenSource = new();

        public IServiceProvider ServiceProvider => _serviceProvider ??= ServiceCollection.BuildServiceProvider();
        private ServiceProvider _serviceProvider;
        public IServiceCollection ServiceCollection { get; } = new ServiceCollection();

        public object[] GetServices() => ServiceCollection.ToArray()
            .Select(x => _serviceProvider.GetService(x.ServiceType)).ToArray();
        public void Inject(object obj)
        {
            foreach (var fieldInfo in obj.GetType().GetFields(ReflectionHelper.Flags))
            {
                if (Attribute.IsDefined(fieldInfo, typeof(InjectAttribute)))
                {
                    fieldInfo.SetValue(obj, ServiceProvider.GetService(fieldInfo.FieldType));
                }
            }
        }

        public void Dispose()
        {
            _cancellationTokenSource.Cancel();
            _serviceProvider.Dispose();
        }
    }
}