private static string GenerateKey(SearchProperties rawKey)
{
const string separator = "?";
var generatedKey = new StringBuilder();
generatedKey.Append(separator);
for (int currentPropertyIndex = 0; currentPropertyIndex < rawKey.List.Count - 1; currentPropertyIndex++)
{
generatedKey.Append($"{rawKey.List[currentPropertyIndex]}={rawKey.List[currentPropertyIndex + 1]}{separator}{rawKey.Signs[currentPropertyIndex]}{separator}");
}
return(generatedKey.ToString());
}
/// <summary>
/// Selects records by the specified key-value pairs.
/// </summary>
/// <param name="searchProperties">Search properties.</param>
/// <returns>Enumerable collection of records.</returns>
public IEnumerable <FileCabinetRecord> Select(SearchProperties searchProperties)
{
if (searchProperties is null)
{
throw new ArgumentNullException(nameof(searchProperties));
}
var key = GenerateKey(searchProperties);
if (!this.RequestCache.TryGetValue(key, out IEnumerable <FileCabinetRecord> records))
{
records = service.SelectByCriteria(searchProperties);
this.RequestCache.Add(key, records);
}
return(records);
}