using System;

namespace MultiWheelC.TrajectoryPlanning.EMPlanner;

/// <summary>Immutable longitudinal solve result; only successful statuses may expose a candidate profile.</summary>
public sealed class LongitudinalPlanningResult
{
    public LongitudinalPlanningResult(EmPlanningStatus status, LongitudinalCandidate candidate, string failureReason)
    {
        if (!Enum.IsDefined(typeof(EmPlanningStatus), status))
            throw new ArgumentOutOfRangeException(nameof(status));
        bool successful = status == EmPlanningStatus.Success || status == EmPlanningStatus.SuccessWithFallback;
        if (successful && candidate == null)
            throw new ArgumentException("Successful longitudinal results require a candidate.", nameof(candidate));
        if (!successful && candidate != null)
            throw new ArgumentException("Failed longitudinal results cannot expose a candidate.", nameof(candidate));

        Status = status;
        Candidate = candidate == null ? null : new LongitudinalCandidate(candidate.KnotTimes, candidate.S, candidate.U,
            candidate.A, candidate.J);
        FailureReason = failureReason ?? string.Empty;
    }

    public EmPlanningStatus Status { get; }

    public LongitudinalCandidate Candidate { get; }

    public string FailureReason { get; }
}