space-game/apps/backend/Ships/AI/ShipBehaviorStates.cs

namespace SpaceGame.Api.Ships.AI;

internal sealed class IdleShipBehaviorState : IShipBehaviorState
{
  public string Kind => "idle";

  public void Plan(SimulationEngine engine, ShipRuntime ship, SimulationWorld world)
  {
    ship.ControllerTask = new ControllerTaskRuntime
    {
      Kind = ControllerTaskKind.Idle,
      Threshold = world.Balance.ArrivalThreshold,
      Status = WorkStatus.Pending,
    };
  }

  public void ApplyEvent(SimulationEngine engine, ShipRuntime ship, SimulationWorld world, string controllerEvent)
  {
  }
}

internal sealed class PatrolShipBehaviorState : IShipBehaviorState
{
  public string Kind => "patrol";

  public void Plan(SimulationEngine engine, ShipRuntime ship, SimulationWorld world)
  {
    if (ship.DefaultBehavior.PatrolPoints.Count == 0)
    {
      ship.DefaultBehavior.Kind = "idle";
      ship.ControllerTask = new ControllerTaskRuntime
      {
        Kind = ControllerTaskKind.Idle,
        Threshold = world.Balance.ArrivalThreshold,
        Status = WorkStatus.Pending,
      };
      return;
    }

    ship.ControllerTask = new ControllerTaskRuntime
    {
      Kind = ControllerTaskKind.Travel,
      TargetPosition = ship.DefaultBehavior.PatrolPoints[ship.DefaultBehavior.PatrolIndex],
      TargetSystemId = ship.SystemId,
      Threshold = 18f,
    };
  }

  public void ApplyEvent(SimulationEngine engine, ShipRuntime ship, SimulationWorld world, string controllerEvent)
  {
    if (controllerEvent == "arrived" && ship.DefaultBehavior.PatrolPoints.Count > 0)
    {
      ship.DefaultBehavior.PatrolIndex = (ship.DefaultBehavior.PatrolIndex + 1) % ship.DefaultBehavior.PatrolPoints.Count;
    }
  }
}

internal sealed class ResourceHarvestShipBehaviorState : IShipBehaviorState
{
  private readonly string resourceItemId;
  private readonly string requiredModule;

  public ResourceHarvestShipBehaviorState(string kind, string resourceItemId, string requiredModule)
  {
    Kind = kind;
    this.resourceItemId = resourceItemId;
    this.requiredModule = requiredModule;
  }

  public string Kind { get; }

  public void Plan(SimulationEngine engine, ShipRuntime ship, SimulationWorld world) =>
      engine.PlanResourceHarvest(ship, world, resourceItemId, requiredModule);

  public void ApplyEvent(SimulationEngine engine, ShipRuntime ship, SimulationWorld world, string controllerEvent)
  {
    switch (ship.DefaultBehavior.Phase, controllerEvent)
    {
      case ("travel-to-node", "arrived"):
        ship.DefaultBehavior.Phase = SimulationEngine.GetShipCargoAmount(ship) >= ship.Definition.CargoCapacity ? "travel-to-station" : "extract";
        break;
      case ("extract", "cargo-full"):
        ship.DefaultBehavior.Phase = "travel-to-station";
        break;
      case ("extract", "node-depleted"):
        ship.DefaultBehavior.Phase = "travel-to-node";
        ship.DefaultBehavior.NodeId = null;
        break;
      case ("travel-to-station", "arrived"):
        ship.DefaultBehavior.Phase = "dock";
        break;
      case ("dock", "docked"):
        ship.DefaultBehavior.Phase = "unload";
        break;
      case ("unload", "unloaded"):
        ship.DefaultBehavior.Phase = "undock";
        break;
      case ("undock", "undocked"):
        ship.DefaultBehavior.Phase = "travel-to-node";
        ship.DefaultBehavior.NodeId = null;
        break;
    }
  }
}

internal sealed class ConstructStationShipBehaviorState : IShipBehaviorState
{
  public string Kind => "construct-station";

  public void Plan(SimulationEngine engine, ShipRuntime ship, SimulationWorld world) =>
      engine.PlanStationConstruction(ship, world);

  public void ApplyEvent(SimulationEngine engine, ShipRuntime ship, SimulationWorld world, string controllerEvent)
  {
    switch (ship.DefaultBehavior.Phase, controllerEvent)
    {
      case ("travel-to-station", "arrived"):
        ship.DefaultBehavior.Phase = "deliver-to-site";
        break;
      case ("deliver-to-site", "construction-delivered"):
        ship.DefaultBehavior.Phase = "build-site";
        break;
      case ("construct-module", "module-constructed"):
      case ("build-site", "site-constructed"):
        ship.DefaultBehavior.Phase = "travel-to-station";
        ship.DefaultBehavior.ModuleId = null;
        break;
    }
  }
}

internal sealed class AttackTargetShipBehaviorState : IShipBehaviorState
{
  public string Kind => "attack-target";

  public void Plan(SimulationEngine engine, ShipRuntime ship, SimulationWorld world) =>
      engine.PlanAttackTarget(ship, world);

  public void ApplyEvent(SimulationEngine engine, ShipRuntime ship, SimulationWorld world, string controllerEvent)
  {
    if (controllerEvent is "target-destroyed" or "target-lost")
    {
      ship.DefaultBehavior.TargetEntityId = null;
    }
  }
}

internal sealed class TradeHaulShipBehaviorState : IShipBehaviorState
{
  public string Kind => "trade-haul";

  public void Plan(SimulationEngine engine, ShipRuntime ship, SimulationWorld world) =>
      engine.PlanTransportHaul(ship, world);

  public void ApplyEvent(SimulationEngine engine, ShipRuntime ship, SimulationWorld world, string controllerEvent)
  {
    switch (ship.DefaultBehavior.Phase, controllerEvent)
    {
      case ("travel-to-source", "arrived"):
        ship.DefaultBehavior.Phase = "dock-source";
        break;
      case ("dock-source", "docked"):
        ship.DefaultBehavior.Phase = "load";
        break;
      case ("load", "loaded"):
        ship.DefaultBehavior.Phase = "undock-from-source";
        break;
      case ("undock-from-source", "undocked"):
        ship.DefaultBehavior.Phase = "travel-to-destination";
        break;
      case ("travel-to-destination", "arrived"):
        ship.DefaultBehavior.Phase = "dock-destination";
        break;
      case ("dock-destination", "docked"):
        ship.DefaultBehavior.Phase = "unload";
        break;
      case ("unload", "unloaded"):
        ship.DefaultBehavior.Phase = "undock-from-destination";
        break;
      case ("undock-from-destination", "undocked"):
        ship.DefaultBehavior.Phase = "travel-to-source";
        break;
    }
  }
}