using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using Microsoft.Extensions.FileProviders;
using Microsoft.Extensions.Primitives;
using Tizen.Applications;
 
namespace Microsoft.AspNetCore.Components.WebView.Maui
{
	/// <summary>
	/// A minimal implementation of an IFileProvider to be used by the BlazorWebView and WebViewManager types.
	/// </summary>
	internal sealed class TizenMauiAssetFileProvider : IFileProvider
	{
		private readonly string _resDir;
 
		public TizenMauiAssetFileProvider(string contentRootDir)
		{
			_resDir = Path.Combine(Application.Current.DirectoryInfo.Resource, contentRootDir);
		}
 
		public IDirectoryContents GetDirectoryContents(string subpath)
			=> new TizenMauiAssetDirectoryContents(Path.Combine(_resDir, subpath));
 
		public IFileInfo GetFileInfo(string subpath)
			=> new TizenMauiAssetFileInfo(Path.Combine(_resDir, subpath));
 
		public IChangeToken Watch(string filter)
			=> NullChangeToken.Singleton;
 
		private sealed class TizenMauiAssetFileInfo : IFileInfo
		{
			private readonly string _filePath;
 
			public TizenMauiAssetFileInfo(string filePath)
			{
				_filePath = filePath;
 
				Name = Path.GetFileName(_filePath);
 
				var fileInfo = new FileInfo(_filePath);
				Exists = fileInfo.Exists;
				Length = Exists ? fileInfo.Length : -1;
			}
 
			public bool Exists { get; }
			public long Length { get; }
			public string PhysicalPath { get; } = null!;
			public string Name { get; }
			public DateTimeOffset LastModified { get; } = DateTimeOffset.FromUnixTimeSeconds(0);
			public bool IsDirectory => false;
 
			public Stream CreateReadStream()
				=> File.OpenRead(_filePath);
		}
 
		// This is never used by BlazorWebView or WebViewManager
		private sealed class TizenMauiAssetDirectoryContents : IDirectoryContents
		{
			public TizenMauiAssetDirectoryContents(string filePath)
			{
			}
 
			public bool Exists => false;
 
			public IEnumerator<IFileInfo> GetEnumerator()
				=> throw new NotImplementedException();
 
			IEnumerator IEnumerable.GetEnumerator()
				=> throw new NotImplementedException();
		}
	}
}