Reduce RequestHelpers.Split usage and remove RequestHelpers.GetGuids usage.

Jellyfin.Api/ModelBinders/PipeDelimitedArrayModelBinder.cs

@@ -0,0 +1,90 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+using Microsoft.Extensions.Logging;
+
+namespace Jellyfin.Api.ModelBinders
+{
+    /// <summary>
+    /// Comma delimited array model binder.
+    /// Returns an empty array of specified type if there is no query parameter.
+    /// </summary>
+    public class PipeDelimitedArrayModelBinder : IModelBinder
+    {
+        private readonly ILogger<PipeDelimitedArrayModelBinder> _logger;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="PipeDelimitedArrayModelBinder"/> class.
+        /// </summary>
+        /// <param name="logger">Instance of the <see cref="ILogger{PipeDelimitedArrayModelBinder}"/> interface.</param>
+        public PipeDelimitedArrayModelBinder(ILogger<PipeDelimitedArrayModelBinder> logger)
+        {
+            _logger = logger;
+        }
+
+        /// <inheritdoc/>
+        public Task BindModelAsync(ModelBindingContext bindingContext)
+        {
+            var valueProviderResult = bindingContext.ValueProvider.GetValue(bindingContext.ModelName);
+            var elementType = bindingContext.ModelType.GetElementType() ?? bindingContext.ModelType.GenericTypeArguments[0];
+            var converter = TypeDescriptor.GetConverter(elementType);
+
+            if (valueProviderResult.Length > 1)
+            {
+                var typedValues = GetParsedResult(valueProviderResult.Values, elementType, converter);
+                bindingContext.Result = ModelBindingResult.Success(typedValues);
+            }
+            else
+            {
+                var value = valueProviderResult.FirstValue;
+
+                if (value != null)
+                {
+                    var splitValues = value.Split('|', StringSplitOptions.RemoveEmptyEntries);
+                    var typedValues = GetParsedResult(splitValues, elementType, converter);
+                    bindingContext.Result = ModelBindingResult.Success(typedValues);
+                }
+                else
+                {
+                    var emptyResult = Array.CreateInstance(elementType, 0);
+                    bindingContext.Result = ModelBindingResult.Success(emptyResult);
+                }
+            }
+
+            return Task.CompletedTask;
+        }
+
+        private Array GetParsedResult(IReadOnlyList<string> values, Type elementType, TypeConverter converter)
+        {
+            var parsedValues = new object?[values.Count];
+            var convertedCount = 0;
+            for (var i = 0; i < values.Count; i++)
+            {
+                try
+                {
+                    parsedValues[i] = converter.ConvertFromString(values[i].Trim());
+                    convertedCount++;
+                }
+                catch (FormatException e)
+                {
+                    _logger.LogWarning(e, "Error converting value.");
+                }
+            }
+
+            var typedValues = Array.CreateInstance(elementType, convertedCount);
+            var typedValueIndex = 0;
+            for (var i = 0; i < parsedValues.Length; i++)
+            {
+                if (parsedValues[i] != null)
+                {
+                    typedValues.SetValue(parsedValues[i], typedValueIndex);
+                    typedValueIndex++;
+                }
+            }
+
+            return typedValues;
+        }
+    }
+}