// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
#nullable enable
 
using System.Globalization;
using Microsoft.Extensions.Primitives;
 
namespace Microsoft.AspNetCore.Mvc.ModelBinding;
 
/// <summary>
/// An <see cref="IValueProvider"/> for jQuery formatted data.
/// </summary>
public abstract class JQueryValueProvider :
    BindingSourceValueProvider,
    IEnumerableValueProvider,
    IKeyRewriterValueProvider
{
    private readonly IDictionary<string, StringValues> _values;
    private PrefixContainer? _prefixContainer;
 
    /// <summary>
    /// Initializes a new instance of the <see cref="JQueryValueProvider"/> class.
    /// </summary>
    /// <param name="bindingSource">The <see cref="BindingSource"/> of the data.</param>
    /// <param name="values">The values.</param>
    /// <param name="culture">The culture to return with ValueProviderResult instances.</param>
    protected JQueryValueProvider(
        BindingSource bindingSource,
        IDictionary<string, StringValues> values,
        CultureInfo? culture)
        : base(bindingSource)
    {
        ArgumentNullException.ThrowIfNull(bindingSource);
        ArgumentNullException.ThrowIfNull(values);
 
        _values = values;
        Culture = culture;
    }
 
    /// <summary>
    /// Gets the <see cref="CultureInfo"/> associated with the values.
    /// </summary>
    public CultureInfo? Culture { get; }
 
    /// <inheritdoc />
    protected PrefixContainer PrefixContainer
    {
        get
        {
            if (_prefixContainer == null)
            {
                _prefixContainer = new PrefixContainer(_values.Keys);
            }
 
            return _prefixContainer;
        }
    }
 
    /// <inheritdoc />
    public override bool ContainsPrefix(string prefix)
    {
        return PrefixContainer.ContainsPrefix(prefix);
    }
 
    /// <inheritdoc />
    public IDictionary<string, string> GetKeysFromPrefix(string prefix)
    {
        return PrefixContainer.GetKeysFromPrefix(prefix);
    }
 
    /// <inheritdoc />
    public override ValueProviderResult GetValue(string key)
    {
        ArgumentNullException.ThrowIfNull(key);
 
        if (_values.TryGetValue(key, out var values) && values.Count > 0)
        {
            return new ValueProviderResult(values, Culture);
        }
 
        return ValueProviderResult.None;
    }
 
    /// <inheritdoc />
    /// <remarks>
    /// Always returns <see langword="null"/> because <see cref="JQueryFormValueProviderFactory"/> creates this
    /// <see cref="IValueProvider"/> with rewritten keys (if original contains brackets) or duplicate keys
    /// (that <see cref="FormValueProvider"/> will match).
    /// </remarks>
    public IValueProvider? Filter()
    {
        return null;
    }
}