Generic Repository with Tracking and No Tracking Options

GenericRepository.cs

using Prognose.Domain;
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Linq.Expressions;

namespace App.Domain
{
    public interface IEntity
    {
        int Id { get; set; }
    }
}


namespace App.Repository
{
    public class GenericRepository<TEntity> : IDisposable where TEntity : class, IEntity
    {
        internal DbContext _context;
        internal DbSet<TEntity> _dbSet;
        private bool _tracking = false;

        public GenericRepository(DbContext context)
        {
            //For Injected Context
            _context = context;
            _dbSet = _context.Set<TEntity>();
        }
        public GenericRepository()
        {
            //For Non-Injected Context
            _context = new AppDomainContext();
            _dbSet = _context.Set<TEntity>();
        }
        public GenericRepository<TEntity> WithTracking()
        {
            _tracking = true;
            return this;
        }
        public GenericRepository<TEntity> WithoutTracking()
        {
            _tracking = false;
            return this;
        }

        public IQueryable<TEntity> All()
        {           
            if (_tracking)
                return _dbSet;
            else
                return _dbSet.AsNoTracking();
        }
        public IEnumerable<TEntity> FindBy(Expression<Func<TEntity, bool>> predicate)
        {
            if (_tracking)
                return _dbSet.Where(predicate);
            else 
                return _dbSet.AsNoTracking().Where(predicate);
        }

        public TEntity Find(int Id)
        {
            if (_tracking)
                return _dbSet.Find(Id);
            else
                return _dbSet.AsNoTracking().Where(x => x.Id == Id).FirstOrDefault();
        }

        public void Insert(TEntity e)
        {
            _dbSet.Add(e);
        }
        public void Update(TEntity e)
        {
            if (!_tracking)
                _context.Entry(e).State = EntityState.Modified;
        }
        public void Delete(int Id)
        {
            Delete(Find(Id));
        }
        public void Delete(TEntity e)
        {
            if (_tracking)
                _dbSet.Remove(e);
            else
                _context.Entry(e).State = EntityState.Deleted;
        }
        public bool Exists(TEntity entity)
        {
            return _dbSet.Any(e => e.Id == entity.Id);
        }
        public void SaveContext()
        {
            _context.SaveChanges();
        }
        public void Dispose()
        {
            _context.Dispose();
        }
    }

}

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