using System;
using System.IO;

namespace ZXLT.FileSystem
{
    public sealed class FileInfo : FileSystemInfo
    {
        public string Extension { get; }
        public override bool Exists { get; }
        public override string Name => _name;
        public string? DirectoryName => Path.GetDirectoryName(this.FullPath);

        public DirectoryInfo Directory
        {
            get
            {
                string directoryName = this.DirectoryName;
                return new DirectoryInfo(directoryName);
            }
        }

        public FileInfo(string fileName)
            : this(fileName ?? throw new ArgumentNullException(nameof(fileName)), (string)null, (string)null, false)
        {
        }

        internal FileInfo(string originalPath, string fullPath = null, string fileName = null, bool isNormalized = false)
        {
            if (fullPath == null)
                fullPath = originalPath;
            this.FullPath = isNormalized ? fullPath ?? originalPath : Path.GetFullPath(fullPath);
            this._name = fileName;
        }
    }
}