/// <summary>
/// Validates the security of a password based on the number
/// of times it has been breached according to Pwned Passwords.
/// </summary>
/// <param name="password">A user password</param>
/// <returns></returns>
public PasswordStatus Validate(string password)
{
// Use the hash function to get the hash value of the password.
_hashValue = _hashFunction.GetHashValue(password).Hash + _hashFunction.GetHashValue(password).Salt;
Console.WriteLine("Hash Value: " + _hashValue); // Demo
// First 5 characters of the hash value
string prefix = _hashValue.Substring(0, 5);
// Full URL address
Uri uri = new Uri(_url + prefix);
Console.WriteLine("Url: " + uri); // Demo
// Http GET request
Task <string> response = client.RequestData(uri);
string hashlistString = response.Result;
// Deserialize json into a dictionary<hashValue,counts>
Dictionary <string, int> hashes = JsonToDictionary(hashlistString);
// Find the hashvalue in the dictionary
int hashCount = FindHash(_hashValue.Substring(5), hashes);
// Check business rules
PasswordStatus status = PasswordCheckingBR.CheckPasswordCount(hashCount);
return(status);
}