using System.Linq;

using System.Net.Http;

namespace JSONAPI.Http

{

/// <summary>

/// Default implementation of <see cref="ISortExpressionExtractor" />

/// </summary>

public class DefaultSortExpressionExtractor : ISortExpressionExtractor

{

private const string SortQueryParamKey = "sort";

public string[] ExtractSortExpressions(HttpRequestMessage requestMessage)

{

var queryParams = requestMessage.GetQueryNameValuePairs();

var sortParam = queryParams.FirstOrDefault(kvp => kvp.Key == SortQueryParamKey);

if (sortParam.Key != SortQueryParamKey) return new string[] {};

return sortParam.Value.Split(',');

}

}

}