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YandexMusic.API/Models/Common/Cover/YCover.cs

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+namespace YandexMusic.API.Models.Common.Cover
+{
+    public sealed class YCoverConverter : JsonConverter
+    {
+        public override bool CanConvert(Type objectType)
+        {
+            return typeof(YCover).IsAssignableFrom(objectType);
+        }
+
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+        {
+            if (reader.TokenType == JsonToken.Null)
+                return null;
+
+            JObject jObject = JObject.Load(reader);
+            YCover cover;
+
+            try
+            {
+                // Фиктивный тип, т.к. у такой обложки нет поля с типом
+                if (jObject["type"] == null)
+                    jObject.Add("type", "color");
+
+                YCoverType type = jObject["error"] != null
+                    ? YCoverType.Error
+                    : jObject["type"].ToObject<YCoverType>();
+
+                switch (type)
+                {
+                    case YCoverType.Error:
+                        cover = jObject.ToObject<YCoverError>();
+                        break;
+                    case YCoverType.Color:
+                        cover = jObject.ToObject<YCoverColor>();
+                        break;
+                    case YCoverType.FromAlbumCover:
+                    case YCoverType.FromArtistPhotos:
+                        cover = jObject.ToObject<YCoverImage>();
+                        break;
+                    case YCoverType.Pic:
+                        cover = jObject.ToObject<YCoverPic>();
+                        break;
+                    case YCoverType.Mosaic:
+                        cover = jObject.ToObject<YCoverMosaic>();
+                        break;
+                    default:
+                        cover = jObject.ToObject<YCover>();
+                        break;
+                }
+            }
+            catch (Exception ex)
+            {
+                throw new Exception($"Ошибка десериализации типа \"{objectType.Name}\".", ex);
+            }
+
+            return cover;
+        }
+
+        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+        {
+            JObject cover = JObject.FromObject(value, serializer);
+
+            cover.WriteTo(writer);
+        }
+    }
+
+    public class YCover
+    {
+        public YCoverType Type { get; set; }
+    }
+}

YandexMusic.API/Models/Common/Cover/YCoverColor.cs

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+namespace YandexMusic.API.Models.Common.Cover
+{
+    public class YCoverColor : YCover
+    {
+        public string Uri { get; set; }
+        public string Color { get; set; }
+    }
+}

YandexMusic.API/Models/Common/Cover/YCoverError.cs

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+namespace YandexMusic.API.Models.Common.Cover
+{
+    public class YCoverError : YCover
+    {
+        public string Error { get; set; }
+    }
+}

YandexMusic.API/Models/Common/Cover/YCoverImage.cs

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+namespace YandexMusic.API.Models.Common.Cover
+{
+    public class YCoverImage : YCover
+    {
+        public string Prefix { get; set; }
+        public string Uri { get; set; }
+    }
+}

YandexMusic.API/Models/Common/Cover/YCoverMosaic.cs

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+namespace YandexMusic.API.Models.Common.Cover
+{
+    public class YCoverMosaic : YCover
+    {
+        public bool Custom { get; set; }
+        public List<string> ItemsUri { get; set; }
+    }
+}

YandexMusic.API/Models/Common/Cover/YCoverPic.cs

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+namespace YandexMusic.API.Models.Common.Cover
+{
+    public class YCoverPic : YCover
+    {
+        public bool Custom { get; set; }
+        public string Dir { get; set; }
+        public bool IsCustom { get; set; }
+        public string Uri { get; set; }
+        public string Version { get; set; }
+    }
+}

YandexMusic.API/Models/Common/Cover/YCoverType.cs

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+using System.Runtime.Serialization;
+
+namespace YandexMusic.API.Models.Common.Cover
+{
+    [JsonConverter(typeof(StringEnumConverter))]
+    public enum YCoverType
+    {
+        Color,
+        Error,
+        [EnumMember(Value = "from-artist-photos")]
+        FromArtistPhotos,
+        [EnumMember(Value = "from-album-cover")]
+        FromAlbumCover,
+        Mosaic,
+        Pic
+    }
+}