//
// Copyright 2020-2022 Signal Messenger, LLC.
// SPDX-License-Identifier: AGPL-3.0-only
//

import Foundation
import SignalFfi

public class ClientZkAuthOperations {
    let serverPublicParams: ServerPublicParams

    public init(serverPublicParams: ServerPublicParams) {
        self.serverPublicParams = serverPublicParams
    }

    /// Produces the `AuthCredentialWithPni` from a server-generated `AuthCredentialWithPniResponse`.
    ///
    /// The `redemptionTime` is provided by the server as an integer, and should be passed through directly.
    public func receiveAuthCredentialWithPniAsServiceId(
        aci: Aci,
        pni: Pni,
        redemptionTime: UInt64,
        authCredentialResponse: AuthCredentialWithPniResponse
    ) throws -> AuthCredentialWithPni {
        return try self.serverPublicParams.withNativeHandle { serverPublicParams in
            try aci.withPointerToFixedWidthBinary { aci in
                try pni.withPointerToFixedWidthBinary { pni in
                    try authCredentialResponse.withUnsafeBorrowedBuffer { authCredentialResponse in
                        try invokeFnReturningVariableLengthSerialized {
                            signal_server_public_params_receive_auth_credential_with_pni_as_service_id(
                                $0,
                                serverPublicParams.const(),
                                aci,
                                pni,
                                redemptionTime,
                                authCredentialResponse
                            )
                        }
                    }
                }
            }
        }
    }

    public func createAuthCredentialPresentation(
        groupSecretParams: GroupSecretParams,
        authCredential: AuthCredentialWithPni
    ) throws -> AuthCredentialPresentation {
        return try self.createAuthCredentialPresentation(
            randomness: Randomness.generate(),
            groupSecretParams: groupSecretParams,
            authCredential: authCredential
        )
    }

    public func createAuthCredentialPresentation(
        randomness: Randomness,
        groupSecretParams: GroupSecretParams,
        authCredential: AuthCredentialWithPni
    ) throws -> AuthCredentialPresentation {
        return try self.serverPublicParams.withNativeHandle { contents in
            try randomness.withUnsafePointerToBytes { randomness in
                try groupSecretParams.withUnsafePointerToSerialized { groupSecretParams in
                    try authCredential.withUnsafeBorrowedBuffer { authCredential in
                        try invokeFnReturningVariableLengthSerialized {
                            signal_server_public_params_create_auth_credential_with_pni_presentation_deterministic(
                                $0,
                                contents.const(),
                                randomness,
                                groupSecretParams,
                                authCredential
                            )
                        }
                    }
                }
            }
        }
    }
}