using System;

namespace Wayne.ForecourtControl.Fusion
{
    /// <summary>
    /// Generates Pump authorization ids based the authorization id
    /// provided by the calling application. If there is no supplied 
    /// authorization id, it will throw an InvalidOperationException.
    /// </summary>
    public class InputParameterAuthorizationIdGenerator : IPumpAuthorizationIdGenerator
    {
        public int GetNext(IAuthorizeParameters authorizeParameters)
        {
            if (authorizeParameters.AuthorizationId.HasValue)
                return authorizeParameters.AuthorizationId.Value;

            throw new InvalidOperationException("Expected caller to supply an Authorization id.");
        }
    }
}