jellyfin/Jellyfin.Api/Helpers/SimilarItemsHelper.cs
2020-11-06 16:39:41 +01:00

183 lines
6.9 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using MediaBrowser.Controller.Dto;
using MediaBrowser.Controller.Entities;
using MediaBrowser.Controller.Library;
using MediaBrowser.Model.Dto;
using MediaBrowser.Model.Entities;
using MediaBrowser.Model.Querying;
namespace Jellyfin.Api.Helpers
{
/// <summary>
/// The similar items helper class.
/// </summary>
public static class SimilarItemsHelper
{
internal static QueryResult<BaseItemDto> GetSimilarItemsResult(
DtoOptions dtoOptions,
IUserManager userManager,
ILibraryManager libraryManager,
IDtoService dtoService,
Guid? userId,
string id,
string? excludeArtistIds,
int? limit,
Type[] includeTypes,
Func<BaseItem, List<PersonInfo>, List<PersonInfo>, BaseItem, int> getSimilarityScore)
{
var user = userId.HasValue && !userId.Equals(Guid.Empty)
? userManager.GetUserById(userId.Value)
: null;
var item = string.IsNullOrEmpty(id) ?
(!userId.Equals(Guid.Empty) ? libraryManager.GetUserRootFolder() :
libraryManager.RootFolder) : libraryManager.GetItemById(id);
var query = new InternalItemsQuery(user)
{
IncludeItemTypes = includeTypes.Select(i => i.Name).ToArray(),
Recursive = true,
DtoOptions = dtoOptions,
ExcludeArtistIds = RequestHelpers.GetGuids(excludeArtistIds)
};
var inputItems = libraryManager.GetItemList(query);
var items = GetSimilaritems(item, libraryManager, inputItems, getSimilarityScore)
.ToList();
var returnItems = items;
if (limit.HasValue && limit < returnItems.Count)
{
returnItems = returnItems.GetRange(0, limit.Value);
}
var dtos = dtoService.GetBaseItemDtos(returnItems, dtoOptions, user);
return new QueryResult<BaseItemDto>
{
Items = dtos,
TotalRecordCount = items.Count
};
}
/// <summary>
/// Gets the similaritems.
/// </summary>
/// <param name="item">The item.</param>
/// <param name="libraryManager">The library manager.</param>
/// <param name="inputItems">The input items.</param>
/// <param name="getSimilarityScore">The get similarity score.</param>
/// <returns>IEnumerable{BaseItem}.</returns>
private static IEnumerable<BaseItem> GetSimilaritems(
BaseItem item,
ILibraryManager libraryManager,
IEnumerable<BaseItem> inputItems,
Func<BaseItem, List<PersonInfo>, List<PersonInfo>, BaseItem, int> getSimilarityScore)
{
var itemId = item.Id;
inputItems = inputItems.Where(i => i.Id != itemId);
var itemPeople = libraryManager.GetPeople(item);
var allPeople = libraryManager.GetPeople(new InternalPeopleQuery
{
AppearsInItemId = item.Id
});
return inputItems.Select(i => new Tuple<BaseItem, int>(i, getSimilarityScore(item, itemPeople, allPeople, i)))
.Where(i => i.Item2 > 2)
.OrderByDescending(i => i.Item2)
.Select(i => i.Item1);
}
private static IEnumerable<string> GetTags(BaseItem item)
{
return item.Tags;
}
/// <summary>
/// Gets the similiarity score.
/// </summary>
/// <param name="item1">The item1.</param>
/// <param name="item1People">The item1 people.</param>
/// <param name="allPeople">All people.</param>
/// <param name="item2">The item2.</param>
/// <returns>System.Int32.</returns>
internal static int GetSimiliarityScore(BaseItem item1, List<PersonInfo> item1People, List<PersonInfo> allPeople, BaseItem item2)
{
var points = 0;
if (!string.IsNullOrEmpty(item1.OfficialRating) && string.Equals(item1.OfficialRating, item2.OfficialRating, StringComparison.OrdinalIgnoreCase))
{
points += 10;
}
// Find common genres
points += item1.Genres.Where(i => item2.Genres.Contains(i, StringComparer.OrdinalIgnoreCase)).Sum(i => 10);
// Find common tags
points += GetTags(item1).Where(i => GetTags(item2).Contains(i, StringComparer.OrdinalIgnoreCase)).Sum(i => 10);
// Find common studios
points += item1.Studios.Where(i => item2.Studios.Contains(i, StringComparer.OrdinalIgnoreCase)).Sum(i => 3);
var item2PeopleNames = allPeople.Where(i => i.ItemId == item2.Id)
.Select(i => i.Name)
.Where(i => !string.IsNullOrWhiteSpace(i))
.DistinctNames()
.ToDictionary(i => i, StringComparer.OrdinalIgnoreCase);
points += item1People.Where(i => item2PeopleNames.ContainsKey(i.Name)).Sum(i =>
{
if (string.Equals(i.Type, PersonType.Director, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Director, StringComparison.OrdinalIgnoreCase))
{
return 5;
}
if (string.Equals(i.Type, PersonType.Actor, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Actor, StringComparison.OrdinalIgnoreCase))
{
return 3;
}
if (string.Equals(i.Type, PersonType.Composer, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Composer, StringComparison.OrdinalIgnoreCase))
{
return 3;
}
if (string.Equals(i.Type, PersonType.GuestStar, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.GuestStar, StringComparison.OrdinalIgnoreCase))
{
return 3;
}
if (string.Equals(i.Type, PersonType.Writer, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Writer, StringComparison.OrdinalIgnoreCase))
{
return 2;
}
return 1;
});
if (item1.ProductionYear.HasValue && item2.ProductionYear.HasValue)
{
var diff = Math.Abs(item1.ProductionYear.Value - item2.ProductionYear.Value);
// Add if they came out within the same decade
if (diff < 10)
{
points += 2;
}
// And more if within five years
if (diff < 5)
{
points += 2;
}
}
return points;
}
}
}