MediaContainerFlags.cs

/* 
 *  Copyright © 2024 Travelonium AB
 *  
 *  This file is part of Arcadeia.
 *  
 *  Arcadeia is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published
 *  by the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *  
 *  Arcadeia is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *  GNU Affero General Public License for more details.
 *  
 *  You should have received a copy of the GNU Affero General Public License
 *  along with Arcadeia. If not, see <https://www.gnu.org/licenses/>.
 *  
 */

using System;
using System.Xml.Linq;
using System.Collections.Generic;
using System.Linq;

namespace Arcadeia
{
   public class MediaContainerFlags
   {
      #region Constants

      public enum Flag
      {
         None = 0,
         Deleted = 1 << 0,
         Favorite = 1 << 1
      }

      #endregion // Constants

      private readonly HashSet<Flag> _flags = new();

      #region Fields

      /// <summary>
      /// Gets or sets a value indicating whether this <see cref="MediaContainerFlags"/> instance is
      /// flagged as favorite.
      /// </summary>
      /// <value>
      ///   <c>true</c> if flagged as favorite; otherwise, <c>false</c>.
      /// </value>
      public bool Favorite
      {
         get
         {
            return GetFlagValue(Flag.Favorite);
         }

         set
         {
            SetFlagValue(Flag.Favorite, value);
         }
      }

      /// <summary>
      /// Gets or sets a value indicating whether this <see cref="MediaContainerFlags"/> instance is
      /// flagged as deleted.
      /// </summary>
      /// <value>
      ///   <c>true</c> if flagged as deleted; otherwise, <c>false</c>.
      /// </value>
      public bool Deleted
      {
         get
         {
            return GetFlagValue(Flag.Deleted);
         }

         set
         {
            SetFlagValue(Flag.Deleted, value);
         }
      }

      /// <summary>
      /// Returns a list of all the flags set on the <see cref="MediaContainer"/>.
      /// </summary>
      public HashSet<Flag> All
      {
         get => _flags;
      }

      #endregion // Fields

      #region Operators


      /// <summary>
      /// Returns all the flags set as a string array.
      /// </summary>
      /// <returns>A string array listing all the set flags.</returns>
      public string[] ToArray()
      {
         return All.Select(flag => Enum.GetName(typeof(MediaContainerFlags.Flag), flag)).OfType<string>().ToArray();
      }

      #endregion // Operators

      #region Constructors

      /// <summary>
      /// Initializes a new instance of the <see cref="MediaContainerFlags"/> class.
      /// </summary>
      public MediaContainerFlags()
      {
      }

      /// <summary>
      /// Initializes a new instance of the <see cref="MediaContainerFlags"/> class by parsing the.
      /// </summary>
      /// <param name="self">The node element representing the current MediaContainer.</param>
      /// <exception cref="NullReferenceException">The MediaContainerFlags cannot be initialized using
      /// a non-existing element!</exception>
      public MediaContainerFlags(IEnumerable<string>? flags)
      {
         if (flags == null) return;

         foreach (var flag in flags)
         {
            _flags.Add(Enum.Parse<Flag>(flag, true));
         }
      }

      #endregion // Constructors

      #region Common Functionality

      /// <summary>
      /// Returns the value of the specified flag.
      /// </summary>
      /// <param name="flag">The flag.</param>
      /// <returns>
      ///   <c>true</c> if flag is set; otherwise, <c>false</c>.
      /// </returns>
      private bool GetFlagValue(Flag flag)
      {
         return _flags.Contains(flag);
      }

      /// <summary>
      /// Sets the value of the supplied flag value.
      /// </summary>
      /// <param name="flag">The flag to set/reset.</param>
      /// <param name="value">if set to <c>true</c> [value].</param>
      private void SetFlagValue(Flag flag, bool value)
      {
         if (value)
         {
            _flags.Add(flag);
         }
         else
         {
            _flags.Remove(flag);
         }
      }

      #endregion // Common Functionality
   }
}