using MediaBrowser.Common.IO;
using MediaBrowser.Controller;
using MediaBrowser.Controller.Entities;
using System;
using System.IO;
using System.Linq;

namespace MediaBrowser.Api.Library
{
    /// <summary>
    /// Class LibraryHelpers
    /// </summary>
    public static class LibraryHelpers
    {
        /// <summary>
        /// The shortcut file extension
        /// </summary>
        private const string ShortcutFileExtension = ".mblink";
        /// <summary>
        /// The shortcut file search
        /// </summary>
        private const string ShortcutFileSearch = "*" + ShortcutFileExtension;

        /// <summary>
        /// Deletes a shortcut from within a virtual folder, within either the default view or a user view
        /// </summary>
        /// <param name="fileSystem">The file system.</param>
        /// <param name="virtualFolderName">Name of the virtual folder.</param>
        /// <param name="mediaPath">The media path.</param>
        /// <param name="user">The user.</param>
        /// <param name="appPaths">The app paths.</param>
        /// <exception cref="System.IO.DirectoryNotFoundException">The media folder does not exist</exception>
        public static void RemoveMediaPath(IFileSystem fileSystem, string virtualFolderName, string mediaPath, User user, IServerApplicationPaths appPaths)
        {
            var rootFolderPath = user != null ? user.RootFolderPath : appPaths.DefaultUserViewsPath;
            var path = Path.Combine(rootFolderPath, virtualFolderName);

            if (!Directory.Exists(path))
            {
                throw new DirectoryNotFoundException(string.Format("The media collection {0} does not exist", virtualFolderName));
            }

            var shortcut = Directory.EnumerateFiles(path, ShortcutFileSearch, SearchOption.AllDirectories).FirstOrDefault(f => fileSystem.ResolveShortcut(f).Equals(mediaPath, StringComparison.OrdinalIgnoreCase));

            if (!string.IsNullOrEmpty(shortcut))
            {
                File.Delete(shortcut);
            }
        }

        /// <summary>
        /// Adds an additional mediaPath to an existing virtual folder, within either the default view or a user view
        /// </summary>
        /// <param name="fileSystem">The file system.</param>
        /// <param name="virtualFolderName">Name of the virtual folder.</param>
        /// <param name="path">The path.</param>
        /// <param name="user">The user.</param>
        /// <param name="appPaths">The app paths.</param>
        /// <exception cref="System.ArgumentException">The path is not valid.</exception>
        /// <exception cref="System.IO.DirectoryNotFoundException">The path does not exist.</exception>
        public static void AddMediaPath(IFileSystem fileSystem, string virtualFolderName, string path, User user, IServerApplicationPaths appPaths)
        {
            if (!Directory.Exists(path))
            {
                throw new DirectoryNotFoundException("The path does not exist.");
            }

            var rootFolderPath = user != null ? user.RootFolderPath : appPaths.DefaultUserViewsPath;
            var virtualFolderPath = Path.Combine(rootFolderPath, virtualFolderName);

            var shortcutFilename = Path.GetFileNameWithoutExtension(path);

            var lnk = Path.Combine(virtualFolderPath, shortcutFilename + ShortcutFileExtension);

            while (File.Exists(lnk))
            {
                shortcutFilename += "1";
                lnk = Path.Combine(virtualFolderPath, shortcutFilename + ShortcutFileExtension);
            }

            fileSystem.CreateShortcut(lnk, path);
        }
    }
}