fun Auth.token(block: TokenAuthConfig.() -> Unit) {
    val config = TokenAuthConfig().apply(block)
    providers.add(TokenAuthProvider(config.secret, config.prefix))
}

class TokenAuthConfig {
    /**
     * Required: The token to provide.
     */
    lateinit var secret: String
    /**
     * The prefix to use. Defaults to `Bearer`
     */
    var prefix: String = "Bearer"
}

/**
 * Client bearer/auth token authentication provider.
 */
class TokenAuthProvider(
    private val secret: String,
    private val prefix: String,
) : AuthProvider {
    override val sendWithoutRequest = true
    override fun isApplicable(auth: HttpAuthHeader) = true

    override suspend fun addRequestHeaders(request: HttpRequestBuilder) {
        request.headers[HttpHeaders.Authorization] = "$prefix $secret"
    }
}