using System;
using System.IO;
using System.Threading.Tasks;
using Wabbajack.DTOs.Streams;
using Wabbajack.Paths;
using Wabbajack.Paths.IO;

namespace Wabbajack.Common
{
    public class NativeFileStreamFactory : IStreamFactory
    {
        protected AbsolutePath _file;

        private DateTime? _lastModifiedCache;

        public NativeFileStreamFactory(AbsolutePath file, IPath path)
        {
            _file = file;
            Name = path;
        }

        public NativeFileStreamFactory(AbsolutePath file)
        {
            _file = file;
            Name = file;
        }

        public ValueTask<Stream> GetStream()
        {
            return new ValueTask<Stream>(_file.Open(FileMode.Open, FileAccess.Read, FileShare.Read));
        }

        public DateTime LastModifiedUtc
        {
            get
            {
                _lastModifiedCache ??= _file.LastModifiedUtc();
                return _lastModifiedCache.Value;
            }
        }

        public IPath Name { get; }
    }
}