Abstract JsonDelimitedArrayConverter

1 files changed, 81 insertions, 0 deletions

diff --git a/MediaBrowser.Common/Json/Converters/JsonDelimitedArrayConverter.cs b/MediaBrowser.Common/Json/Converters/JsonDelimitedArrayConverter.cs
new file mode 100644
index 000000000..b691798c9
--- /dev/null
+++ b/MediaBrowser.Common/Json/Converters/JsonDelimitedArrayConverter.cs
@@ -0,0 +1,81 @@
+using System;
+using System.ComponentModel;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace MediaBrowser.Common.Json.Converters
+{
+    /// <summary>
+    /// Convert delimited string to array of type.
+    /// </summary>
+    /// <typeparam name="T">Type to convert to.</typeparam>
+    public abstract class JsonDelimitedArrayConverter<T> : JsonConverter<T[]?>
+    {
+        private readonly TypeConverter _typeConverter;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JsonDelimitedArrayConverter{T}"/> class.
+        /// </summary>
+        protected JsonDelimitedArrayConverter()
+        {
+            _typeConverter = TypeDescriptor.GetConverter(typeof(T));
+        }
+
+        /// <summary>
+        /// Gets the array delimiter.
+        /// </summary>
+        protected virtual char Delimiter { get; }
+
+        /// <inheritdoc />
+        public override T[]? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+        {
+            if (reader.TokenType == JsonTokenType.String)
+            {
+                // GetString can't return null here because we already handled it above
+                var stringEntries = reader.GetString()?.Split(Delimiter, StringSplitOptions.RemoveEmptyEntries);
+                if (stringEntries == null || stringEntries.Length == 0)
+                {
+                    return Array.Empty<T>();
+                }
+
+                var parsedValues = new object[stringEntries.Length];
+                var convertedCount = 0;
+                for (var i = 0; i < stringEntries.Length; i++)
+                {
+                    try
+                    {
+                        parsedValues[i] = _typeConverter.ConvertFrom(stringEntries[i].Trim());
+                        convertedCount++;
+                    }
+                    catch (FormatException)
+                    {
+                        // TODO log when upgraded to .Net6
+                        // https://github.com/dotnet/runtime/issues/42975
+                        // _logger.LogDebug(e, "Error converting value.");
+                    }
+                }
+
+                var typedValues = new T[convertedCount];
+                var typedValueIndex = 0;
+                for (var i = 0; i < stringEntries.Length; i++)
+                {
+                    if (parsedValues[i] != null)
+                    {
+                        typedValues.SetValue(parsedValues[i], typedValueIndex);
+                        typedValueIndex++;
+                    }
+                }
+
+                return typedValues;
+            }
+
+            return JsonSerializer.Deserialize<T[]>(ref reader, options);
+        }
+
+        /// <inheritdoc />
+        public override void Write(Utf8JsonWriter writer, T[]? value, JsonSerializerOptions options)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}