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use crate::chaum_pedersen::ChaumPedersen;

/// Executes the Chaum-Pedersen protocol using a generic implementation.
///
/// This function demonstrates a typical execution flow of the Chaum-Pedersen
/// cryptographic protocol. It encapsulates the roles of both the client and
/// the server, illustrating the generation of commitment, challenge, response,
/// and the verification process.
///
/// The function is generic over a type `T` that implements the `ChaumPedersen`
/// trait, allowing it to work with any specific cryptographic scheme that
/// conforms to the protocol.
///
/// # Arguments
/// * `params` - Reference to the group parameters. These parameters are essential
///   for the cryptographic operations and depend on the specific implementation
///   of the Chaum-Pedersen protocol.
/// * `x` - Reference to the secret value. This is the secret that the client
///   wants to prove knowledge of without revealing it.
///
/// # Type Parameters
/// * `T` - A type that implements the `ChaumPedersen` trait. This type dictates
///   the specifics of the cryptographic operations used in the protocol.
///
/// # Returns
/// Returns a boolean indicating whether the verification was successful. A value
/// of `true` means that the client successfully proved knowledge of the secret
/// without revealing it, while `false` indicates a failure in the protocol execution.
///
/// # Example
/// ```
/// // Assume `DiscreteLogChaumPedersen` implements `ChaumPedersen`.
/// use zk_pass::chaum_pedersen::test::test_execute_protocol;
/// use zk_pass::chaum_pedersen::discretelog::DiscreteLogChaumPedersen;
/// use zk_pass::chaum_pedersen::constants::RFC5114_MODP_2048_256_BIT_PARAMS;
/// use rand::rngs::OsRng;
/// use num_bigint::RandBigInt;
///
/// let params = RFC5114_MODP_2048_256_BIT_PARAMS.to_owned();
/// let mut rng = OsRng;
/// let secret = rng.gen_biguint_below(&params.p);
///
/// let result = test_execute_protocol::<DiscreteLogChaumPedersen>(&params, &secret);
/// assert_eq!(result, true);
/// ```
pub fn test_execute_protocol<T>(params: &T::GroupParameters, x: &T::Secret) -> bool
where
    T: ChaumPedersen,
{
    // The client calculates the commitment using their secret and the group parameters.
    let (cp, k) = T::commitment(params, x);

    // The server (simulated here) sends a challenge to the client.
    let c = T::challenge(params);

    // The client calculates the response based on the commitment random, challenge,
    // and their secret.
    let s = T::challenge_response(params, &k, &c, &x);

    // The server (simulated here) verifies the response against the challenge and
    // commitment parameters.
    T::verify(params, &s, &c, &cp)
}