namespace SpaceGame.Api.Industry.Planning;

internal static class CommodityOperationalSignal
{
  internal static float ComputeNeedScore(FactionCommoditySnapshot commodity, float targetLevelSeconds)
  {
    var productionDeficit = MathF.Max(0f, commodity.ConsumptionRatePerSecond - commodity.ProjectedProductionRatePerSecond);
    var levelDeficit = MathF.Max(0f, targetLevelSeconds - commodity.LevelSeconds) / MathF.Max(targetLevelSeconds, 1f);
    var backlogPressure = MathF.Max(0f, commodity.BuyBacklog + commodity.ReservedForConstruction - commodity.AvailableStock);

    var levelWeight = commodity.Level switch
    {
      CommodityLevelKind.Critical => 140f,
      CommodityLevelKind.Low => 80f,
      CommodityLevelKind.Stable => 20f,
      _ => 0f,
    };

    return levelWeight
      + (productionDeficit * 140f)
      + (levelDeficit * 120f)
      + backlogPressure;
  }

  internal static bool IsOperational(FactionCommoditySnapshot commodity, float targetLevelSeconds) =>
    commodity.ProjectedProductionRatePerSecond > 0.01f
    && commodity.ProjectedNetRatePerSecond >= -0.01f
    && commodity.LevelSeconds >= targetLevelSeconds
    && commodity.Level is CommodityLevelKind.Stable or CommodityLevelKind.Surplus;

  internal static bool IsStrained(FactionCommoditySnapshot commodity, float targetLevelSeconds) =>
    !IsOperational(commodity, targetLevelSeconds)
    || commodity.Level is CommodityLevelKind.Critical or CommodityLevelKind.Low;

  internal static float ComputeFeasibilityFactor(FactionCommoditySnapshot commodity, float targetLevelSeconds)
  {
    if (commodity.AvailableStock <= 0.01f && commodity.ProjectedProductionRatePerSecond <= 0.01f)
    {
      return 0.65f;
    }

    if (commodity.Level is CommodityLevelKind.Critical)
    {
      return 0.72f;
    }

    if (commodity.Level is CommodityLevelKind.Low || commodity.LevelSeconds < targetLevelSeconds)
    {
      return 0.84f;
    }

    return 1f;
  }
}