space-game/apps/backend/Simulation/SimulationEngine.PowerAndInventorySystems.cs

using SpaceGame.Simulation.Api.Contracts;
using SpaceGame.Simulation.Api.Data;

namespace SpaceGame.Simulation.Api.Simulation;

public sealed partial class SimulationEngine
{
    private const float StationEnergyCellToEnergyRatio = 1f;

    private static bool HasShipModules(ShipDefinition definition, params string[] modules) =>
        modules.All(moduleId => definition.Modules.Contains(moduleId, StringComparer.Ordinal));

    private static bool CanTransportWorkers(ShipRuntime ship) =>
        CountModules(ship.Definition.Modules, "habitat-ring") > 0;

    private static float GetWorkerTransportCapacity(ShipRuntime ship) =>
        CountModules(ship.Definition.Modules, "habitat-ring") * 120f;

    private static void UpdateStationPower(SimulationWorld world, float deltaSeconds, ICollection<SimulationEventRecord> events)
    {
        foreach (var station in world.Stations)
        {
            var previousEnergy = station.EnergyStored;
            GenerateStationEnergy(station, world, deltaSeconds);

            if (previousEnergy > 0.01f && station.EnergyStored <= 0.01f && GetInventoryAmount(station.Inventory, "fuel") <= 0.01f)
            {
                events.Add(new SimulationEventRecord("station", station.Id, "power-lost", $"{station.Definition.Label} ran out of fuel and power", DateTimeOffset.UtcNow));
            }
        }
    }

    private static void UpdateShipPower(ShipRuntime ship, SimulationWorld world, float deltaSeconds, ICollection<SimulationEventRecord> events)
    {
        var previousEnergy = ship.EnergyStored;
        GenerateShipEnergy(ship, world, deltaSeconds);

        if (previousEnergy > 0.01f && ship.EnergyStored <= 0.01f && GetInventoryAmount(ship.Inventory, "fuel") <= 0.01f)
        {
            events.Add(new SimulationEventRecord("ship", ship.Id, "power-lost", $"{ship.Definition.Label} ran out of fuel and power", DateTimeOffset.UtcNow));
        }
    }

    private static void GenerateStationEnergy(StationRuntime station, SimulationWorld world, float deltaSeconds)
    {
        var powerCores = CountModules(station.InstalledModules, "power-core");
        var tanks = CountModules(station.InstalledModules, "liquid-tank");
        if (powerCores <= 0 || tanks <= 0)
        {
            station.EnergyStored = 0f;
            station.Inventory.Remove("fuel");
            return;
        }

        var energyCapacity = powerCores * StationEnergyPerPowerCore;
        var fuelStored = GetInventoryAmount(station.Inventory, "fuel");
        var desiredEnergy = MathF.Max(0f, energyCapacity - station.EnergyStored);
        if (desiredEnergy <= 0.01f)
        {
            station.EnergyStored = MathF.Min(station.EnergyStored, energyCapacity);
            station.Inventory["fuel"] = MathF.Min(fuelStored, tanks * StationFuelPerTank);
            return;
        }

        var solarGenerated = MathF.Min(desiredEnergy, GetStationSolarGeneration(station, world) * deltaSeconds);
        if (solarGenerated > 0.01f)
        {
            station.EnergyStored = MathF.Min(energyCapacity, station.EnergyStored + solarGenerated);
            desiredEnergy = MathF.Max(0f, energyCapacity - station.EnergyStored);
        }

        if (desiredEnergy > 0.01f && fuelStored <= 0.01f)
        {
            var energyCells = GetInventoryAmount(station.Inventory, "energy-cell");
            if (energyCells > 0.01f)
            {
                var consumedCells = MathF.Min(energyCells, desiredEnergy / StationEnergyCellToEnergyRatio);
                RemoveInventory(station.Inventory, "energy-cell", consumedCells);
                station.EnergyStored = MathF.Min(energyCapacity, station.EnergyStored + (consumedCells * StationEnergyCellToEnergyRatio));
                desiredEnergy = MathF.Max(0f, energyCapacity - station.EnergyStored);
            }
        }

        if (desiredEnergy <= 0.01f || fuelStored <= 0.01f)
        {
            station.EnergyStored = MathF.Min(station.EnergyStored, energyCapacity);
            station.Inventory["fuel"] = MathF.Min(fuelStored, tanks * StationFuelPerTank);
            return;
        }

        var generated = MathF.Min(desiredEnergy, powerCores * 24f * deltaSeconds);
        var requiredFuel = generated / StationFuelToEnergyRatio;
        var consumedFuel = MathF.Min(requiredFuel, fuelStored);
        var actualGenerated = consumedFuel * StationFuelToEnergyRatio;

        RemoveInventory(station.Inventory, "fuel", consumedFuel);
        station.EnergyStored = MathF.Min(energyCapacity, station.EnergyStored + actualGenerated);
    }

    private static float GetStationFuelCapacity(StationRuntime station) =>
        CountModules(station.InstalledModules, "liquid-tank") * StationFuelPerTank;

    private static float GetStationEnergyCapacity(StationRuntime station) =>
        CountModules(station.InstalledModules, "power-core") * StationEnergyPerPowerCore;

    private static float GetStationSolarGeneration(StationRuntime station, SimulationWorld world) =>
        world.Balance.Energy.StationSolarCharge * (1f + CountModules(station.InstalledModules, "solar-array"));

    private static float GetStationStorageCapacity(StationRuntime station, string storageClass)
    {
        var baseCapacity = station.Definition.Storage.TryGetValue(storageClass, out var capacity)
            ? capacity
            : 0f;

        var extraBulkBays = Math.Max(0, CountModules(station.InstalledModules, "bulk-bay") - CountModules(station.Definition.Modules, "bulk-bay"));
        var extraLiquidTanks = Math.Max(0, CountModules(station.InstalledModules, "liquid-tank") - CountModules(station.Definition.Modules, "liquid-tank"));
        var extraGasTanks = Math.Max(0, CountModules(station.InstalledModules, "gas-tank") - CountModules(station.Definition.Modules, "gas-tank"));
        var extraContainerBays = Math.Max(0, CountModules(station.InstalledModules, "container-bay") - CountModules(station.Definition.Modules, "container-bay"));
        var moduleBonus = storageClass switch
        {
            "bulk-solid" => extraBulkBays * 1000f,
            "bulk-liquid" => extraLiquidTanks * 500f,
            "bulk-gas" => extraGasTanks * 500f,
            "container" => extraContainerBays * 800f,
            _ => 0f,
        };

        return baseCapacity + moduleBonus;
    }

    private static void GenerateShipEnergy(ShipRuntime ship, SimulationWorld world, float deltaSeconds)
    {
        var reactors = CountModules(ship.Definition.Modules, "reactor-core");
        var capacitors = CountModules(ship.Definition.Modules, "capacitor-bank");
        if (reactors <= 0 || capacitors <= 0)
        {
            ship.EnergyStored = 0f;
            ship.Inventory.Remove("fuel");
            return;
        }

        var energyCapacity = capacitors * CapacitorEnergyPerModule;
        var fuelCapacity = reactors * ShipFuelPerReactor;
        var fuelStored = GetInventoryAmount(ship.Inventory, "fuel");
        var desiredEnergy = MathF.Max(0f, energyCapacity - ship.EnergyStored);
        if (desiredEnergy <= 0.01f || fuelStored <= 0.01f)
        {
            ship.EnergyStored = MathF.Min(ship.EnergyStored, energyCapacity);
            ship.Inventory["fuel"] = MathF.Min(fuelStored, fuelCapacity);
            return;
        }

        var generated = MathF.Min(desiredEnergy, world.Balance.Energy.ShipRechargeRate * reactors * deltaSeconds);
        var requiredFuel = generated / ShipFuelToEnergyRatio;
        var consumedFuel = MathF.Min(requiredFuel, fuelStored);
        var actualGenerated = consumedFuel * ShipFuelToEnergyRatio;

        RemoveInventory(ship.Inventory, "fuel", consumedFuel);
        ship.EnergyStored = MathF.Min(energyCapacity, ship.EnergyStored + actualGenerated);
    }

    private static bool TryConsumeShipEnergy(ShipRuntime ship, float amount)
    {
        if (ship.EnergyStored + 0.0001f < amount)
        {
            return false;
        }

        ship.EnergyStored = MathF.Max(0f, ship.EnergyStored - amount);
        return true;
    }

    private static bool TryConsumeStationEnergy(StationRuntime station, float amount)
    {
        if (station.EnergyStored + 0.0001f < amount)
        {
            return false;
        }

        station.EnergyStored = MathF.Max(0f, station.EnergyStored - amount);
        return true;
    }

    private static int CountModules(IEnumerable<string> modules, string moduleId) =>
        modules.Count(candidate => string.Equals(candidate, moduleId, StringComparison.Ordinal));

    private static float GetInventoryAmount(IReadOnlyDictionary<string, float> inventory, string itemId) =>
        inventory.TryGetValue(itemId, out var amount) ? amount : 0f;

    private static void AddInventory(IDictionary<string, float> inventory, string itemId, float amount)
    {
        if (amount <= 0f)
        {
            return;
        }

        inventory[itemId] = GetInventoryAmount((IReadOnlyDictionary<string, float>)inventory, itemId) + amount;
    }

    private static float RemoveInventory(IDictionary<string, float> inventory, string itemId, float amount)
    {
        var current = GetInventoryAmount((IReadOnlyDictionary<string, float>)inventory, itemId);
        var removed = MathF.Min(current, amount);
        var remaining = current - removed;
        if (remaining <= 0.001f)
        {
            inventory.Remove(itemId);
        }
        else
        {
            inventory[itemId] = remaining;
        }

        return removed;
    }

    private static bool HasStationModules(StationRuntime station, params string[] modules) =>
        modules.All(moduleId => station.InstalledModules.Contains(moduleId, StringComparer.Ordinal));

    private static bool CanExtractNode(ShipRuntime ship, ResourceNodeRuntime node) =>
        node.ItemId switch
        {
            "ore" => HasShipModules(ship.Definition, "reactor-core", "capacitor-bank", "mining-turret"),
            "gas" => HasShipModules(ship.Definition, "reactor-core", "capacitor-bank", "gas-extractor"),
            _ => false,
        };

    private static bool CanBuildClaimBeacon(ShipRuntime ship) =>
        string.Equals(ship.Definition.Role, "military", StringComparison.Ordinal);

    private static float GetShipFuelCapacity(ShipRuntime ship) =>
        CountModules(ship.Definition.Modules, "reactor-core") * ShipFuelPerReactor;

    private static float GetShipAvailableEnergyBudget(ShipRuntime ship) =>
        ship.EnergyStored + (GetInventoryAmount(ship.Inventory, "fuel") * ShipFuelToEnergyRatio);

    private static float GetShipFuelReserve(ShipRuntime ship, float plannedFuel)
    {
        var capacity = GetShipFuelCapacity(ship);
        var reserveRatio = ship.Definition.CargoItemId == "gas" ? 0.4f : 0.3f;
        var reserve = MathF.Max(16f, MathF.Max(capacity * 0.18f, plannedFuel * reserveRatio));
        return MathF.Min(capacity, reserve);
    }

    private static float EstimateFuelForEnergyDemand(ShipRuntime ship, float energyDemand) =>
        MathF.Max(0f, energyDemand - ship.EnergyStored) / ShipFuelToEnergyRatio;

    private static float EstimateTimedEnergyUse(SimulationWorld world, float durationSeconds, float drainPerSecond) =>
        MathF.Max(0f, durationSeconds) * drainPerSecond;

    private static float EstimateTravelEnergy(
        ShipRuntime ship,
        SimulationWorld world,
        Vector3 fromPosition,
        string fromSystemId,
        Vector3 toPosition,
        string toSystemId)
    {
        if (!string.Equals(fromSystemId, toSystemId, StringComparison.Ordinal))
        {
            var destinationEntryNode = ResolveSystemEntryNode(world, toSystemId);
            var destinationEntryPosition = destinationEntryNode?.Position ?? toPosition;
            var originSystemPosition = ResolveSystemGalaxyPosition(world, fromSystemId);
            var destinationSystemPosition = ResolveSystemGalaxyPosition(world, toSystemId);
            var ftlDistance = originSystemPosition.DistanceTo(destinationSystemPosition);
            var ftlDuration = ftlDistance / MathF.Max(ship.Definition.FtlSpeed, 0.01f);
            return EstimateTimedEnergyUse(world, ship.Definition.SpoolTime, world.Balance.Energy.IdleDrain)
                + EstimateTimedEnergyUse(world, ftlDuration, world.Balance.Energy.WarpDrain)
                + EstimateInSystemTravelEnergy(ship, world, destinationEntryPosition, toPosition);
        }

        return EstimateInSystemTravelEnergy(ship, world, fromPosition, toPosition);
    }

    private static float EstimateInSystemTravelEnergy(ShipRuntime ship, SimulationWorld world, Vector3 fromPosition, Vector3 toPosition)
    {
        var distance = fromPosition.DistanceTo(toPosition);
        if (distance <= world.Balance.ArrivalThreshold)
        {
            return 0f;
        }

        if (distance <= WarpEngageDistanceKilometers)
        {
            var localDuration = distance / MathF.Max(GetLocalTravelSpeed(ship), 0.01f);
            return EstimateTimedEnergyUse(world, localDuration, world.Balance.Energy.MoveDrain);
        }

        var warpSpoolDuration = MathF.Max(0.4f, ship.Definition.SpoolTime * 0.5f);
        var warpDuration = distance / MathF.Max(GetWarpTravelSpeed(ship), 0.01f);
        return EstimateTimedEnergyUse(world, warpSpoolDuration, world.Balance.Energy.IdleDrain)
            + EstimateTimedEnergyUse(world, warpDuration, world.Balance.Energy.WarpDrain);
    }

    private static float EstimateDockingEnergy(SimulationWorld world) =>
        EstimateTimedEnergyUse(world, world.Balance.DockingDuration, world.Balance.Energy.MoveDrain)
        + EstimateTimedEnergyUse(world, 6f, world.Balance.Energy.IdleDrain);

    private static float EstimateUndockingEnergy(SimulationWorld world) =>
        EstimateTimedEnergyUse(world, world.Balance.UndockingDuration, world.Balance.Energy.MoveDrain)
        + EstimateTimedEnergyUse(world, 4f, world.Balance.Energy.IdleDrain);

    private static float EstimateExtractionEnergy(ShipRuntime ship, SimulationWorld world)
    {
        var remainingCargo = MathF.Max(0f, ship.Definition.CargoCapacity - GetShipCargoAmount(ship));
        if (remainingCargo <= 0.01f)
        {
            return 0f;
        }

        var cycles = MathF.Ceiling(remainingCargo / MathF.Max(world.Balance.MiningRate, 0.01f));
        return EstimateTimedEnergyUse(world, cycles * world.Balance.MiningCycleSeconds, world.Balance.Energy.MoveDrain)
            + EstimateTimedEnergyUse(world, cycles * 1.5f, world.Balance.Energy.IdleDrain);
    }

    private static float EstimateConstructionEnergy(ShipRuntime ship, SimulationWorld world, StationRuntime station)
    {
        var holdPosition = GetConstructionHoldPosition(station, ship.Id);
        var travelEnergy = EstimateTravelEnergy(ship, world, ship.Position, ship.SystemId, holdPosition, station.SystemId);
        var site = GetConstructionSiteForStation(world, station.Id);
        if (site is not null && site.State == ConstructionSiteStateKinds.Active && IsConstructionSiteReady(world, site))
        {
            if (world.ModuleRecipes.TryGetValue(site.BlueprintId ?? string.Empty, out var siteRecipe))
            {
                return travelEnergy + EstimateTimedEnergyUse(world, siteRecipe.Duration, world.Balance.Energy.IdleDrain);
            }

            return travelEnergy;
        }

        var moduleId = site?.BlueprintId ?? GetNextStationModuleToBuild(station, world);
        if (moduleId is not null
            && world.ModuleRecipes.TryGetValue(moduleId, out var recipe)
            && CanStartModuleConstruction(station, recipe))
        {
            return travelEnergy + EstimateTimedEnergyUse(world, recipe.Duration, world.Balance.Energy.IdleDrain);
        }

        return travelEnergy;
    }

    private static float EstimateResourceHarvestEnergy(ShipRuntime ship, SimulationWorld world)
    {
        var cargoItemId = ship.Definition.CargoItemId;
        if (cargoItemId is null)
        {
            return 0f;
        }

        var requiredModule = cargoItemId == "gas" ? "gas-extractor" : "mining-turret";
        var behavior = ship.DefaultBehavior;
        var refinery = SelectBestBuyStation(world, ship, cargoItemId, behavior.StationId);
        var node = behavior.NodeId is null
            ? world.Nodes
                .Where(candidate =>
                    (behavior.AreaSystemId is null || candidate.SystemId == behavior.AreaSystemId) &&
                    candidate.ItemId == cargoItemId &&
                    candidate.OreRemaining > 0.01f)
                .OrderByDescending(candidate => candidate.OreRemaining)
                .FirstOrDefault()
            : world.Nodes.FirstOrDefault(candidate => candidate.Id == behavior.NodeId && candidate.OreRemaining > 0.01f);
        if (refinery is null || node is null || !HasShipModules(ship.Definition, "reactor-core", "capacitor-bank", requiredModule))
        {
            return 0f;
        }

        var currentPosition = ship.Position;
        var currentSystemId = ship.SystemId;
        var energy = 0f;
        var cargoAmount = GetShipCargoAmount(ship);
        if (ship.DockedStationId == refinery.Id)
        {
            currentPosition = GetUndockTargetPosition(refinery, ship.AssignedDockingPadIndex, world.Balance.UndockDistance);
            currentSystemId = refinery.SystemId;
            energy += EstimateUndockingEnergy(world);
        }

        if (cargoAmount > 0.01f)
        {
            energy += EstimateTravelEnergy(ship, world, currentPosition, currentSystemId, refinery.Position, refinery.SystemId);
            return energy + EstimateDockingEnergy(world);
        }

        var holdPosition = GetResourceHoldPosition(node.Position, ship.Id, 20f);
        energy += EstimateTravelEnergy(ship, world, currentPosition, currentSystemId, holdPosition, node.SystemId);
        energy += EstimateExtractionEnergy(ship, world);
        energy += EstimateTravelEnergy(ship, world, holdPosition, node.SystemId, refinery.Position, refinery.SystemId);
        energy += EstimateDockingEnergy(world);
        return energy;
    }

    private static float EstimateResourceReturnEnergy(ShipRuntime ship, SimulationWorld world)
    {
        var cargoItemId = ship.Definition.CargoItemId;
        if (cargoItemId is null)
        {
            return 0f;
        }

        var refinery = SelectBestBuyStation(world, ship, cargoItemId, ship.DefaultBehavior.StationId);
        if (refinery is null)
        {
            return 0f;
        }

        var currentPosition = ship.Position;
        var currentSystemId = ship.SystemId;
        return EstimateTravelEnergy(ship, world, currentPosition, currentSystemId, refinery.Position, refinery.SystemId)
            + EstimateDockingEnergy(world);
    }

    private static float EstimateTransportEnergy(ShipRuntime ship, SimulationWorld world)
    {
        var cargoItemId = ship.Definition.CargoItemId;
        if (cargoItemId is null)
        {
            return 0f;
        }

        var behavior = ship.DefaultBehavior;
        var source = SelectBestSellStation(world, ship, cargoItemId, behavior.StationId);
        var destination = SelectBestBuyStation(world, ship, cargoItemId, behavior.StationId);
        if (source is null && destination is null)
        {
            return 0f;
        }

        var cargoAmount = GetShipCargoAmount(ship);
        var currentPosition = ship.Position;
        var currentSystemId = ship.SystemId;
        if (ship.DockedStationId is not null)
        {
            var dockedStation = world.Stations.FirstOrDefault(candidate => candidate.Id == ship.DockedStationId);
            if (dockedStation is not null)
            {
                currentPosition = GetUndockTargetPosition(dockedStation, ship.AssignedDockingPadIndex, world.Balance.UndockDistance);
                currentSystemId = dockedStation.SystemId;
            }
        }

        var targetStation = cargoAmount > 0.01f ? destination : source;
        if (targetStation is null)
        {
            return ship.DockedStationId is not null ? EstimateUndockingEnergy(world) : 0f;
        }

        var energy = ship.DockedStationId is not null ? EstimateUndockingEnergy(world) : 0f;
        energy += EstimateTravelEnergy(ship, world, currentPosition, currentSystemId, targetStation.Position, targetStation.SystemId);
        return energy + EstimateDockingEnergy(world);
    }

    private static float EstimateShipMissionEnergyDemand(ShipRuntime ship, SimulationWorld world) =>
        ship.DefaultBehavior.Kind switch
        {
            "auto-mine" or "auto-harvest-gas" => EstimateResourceHarvestEnergy(ship, world),
            "auto-supply-energy" => EstimateTransportEnergy(ship, world),
            "construct-station" when ship.DefaultBehavior.StationId is not null
                => world.Stations.FirstOrDefault(candidate => candidate.Id == ship.DefaultBehavior.StationId) is { } station
                    ? EstimateConstructionEnergy(ship, world, station)
                    : 0f,
            _ when ship.ControllerTask.TargetPosition is { } targetPosition && ship.ControllerTask.TargetSystemId is { } targetSystemId
                => EstimateTravelEnergy(ship, world, ship.Position, ship.SystemId, targetPosition, targetSystemId),
            _ => 0f,
        };

    private static float GetShipRefuelTarget(ShipRuntime ship, SimulationWorld world)
    {
        var capacity = GetShipFuelCapacity(ship);
        var missionFuel = EstimateFuelForEnergyDemand(ship, EstimateShipMissionEnergyDemand(ship, world));
        var reserveFuel = GetShipFuelReserve(ship, missionFuel);
        return MathF.Min(capacity, missionFuel + reserveFuel);
    }

    internal static bool NeedsRefuel(ShipRuntime ship, SimulationWorld world) =>
        GetInventoryAmount(ship.Inventory, "fuel") + 0.01f < GetShipRefuelTarget(ship, world);

    internal static bool NeedsEmergencyReturn(ShipRuntime ship, SimulationWorld world)
    {
        if (ship.DefaultBehavior.Kind is not "auto-mine" and not "auto-harvest-gas")
        {
            return false;
        }

        var returnEnergy = EstimateResourceReturnEnergy(ship, world);
        var reserveFuel = GetShipFuelReserve(ship, EstimateFuelForEnergyDemand(ship, returnEnergy));
        var requiredBudget = returnEnergy + (reserveFuel * ShipFuelToEnergyRatio);
        return GetShipAvailableEnergyBudget(ship) + 0.01f < requiredBudget;
    }

    private static float ComputeWorkforceRatio(float population, float workforceRequired)
    {
        if (workforceRequired <= 0.01f)
        {
            return 1f;
        }

        var staffedRatio = MathF.Min(1f, population / workforceRequired);
        return 0.1f + (0.9f * staffedRatio);
    }

    private static string? GetStorageRequirement(string storageClass) =>
        storageClass switch
        {
            "bulk-solid" => "bulk-bay",
            "bulk-liquid" => "liquid-tank",
            "bulk-gas" => "gas-tank",
            _ => null,
        };

    private static float TryAddStationInventory(SimulationWorld world, StationRuntime station, string itemId, float amount)
    {
        if (amount <= 0f || !world.ItemDefinitions.TryGetValue(itemId, out var itemDefinition))
        {
            return 0f;
        }

        var storageClass = itemDefinition.Storage;
        var requiredModule = GetStorageRequirement(storageClass);
        if (requiredModule is not null && !station.InstalledModules.Contains(requiredModule, StringComparer.Ordinal))
        {
            return 0f;
        }

        var capacity = GetStationStorageCapacity(station, storageClass);
        if (capacity <= 0.01f)
        {
            return 0f;
        }

        var used = station.Inventory
            .Where(entry => world.ItemDefinitions.TryGetValue(entry.Key, out var definition) && definition.Storage == storageClass)
            .Sum(entry => entry.Value);
        var accepted = MathF.Min(amount, MathF.Max(0f, capacity - used));
        if (accepted <= 0.01f)
        {
            return 0f;
        }

        AddInventory(station.Inventory, itemId, accepted);
        return accepted;
    }

    private static bool CanStartModuleConstruction(StationRuntime station, ModuleRecipeDefinition recipe) =>
        recipe.Inputs.All(input => GetInventoryAmount(station.Inventory, input.ItemId) + 0.001f >= input.Amount);

    private static ConstructionSiteRuntime? GetConstructionSiteForStation(SimulationWorld world, string stationId) =>
        world.ConstructionSites.FirstOrDefault(site =>
            string.Equals(site.StationId, stationId, StringComparison.Ordinal)
            && site.State is not ConstructionSiteStateKinds.Completed and not ConstructionSiteStateKinds.Destroyed);

    private static float GetConstructionDeliveredAmount(SimulationWorld world, ConstructionSiteRuntime site, string itemId)
    {
        if (site.StationId is not null
            && world.Stations.FirstOrDefault(candidate => candidate.Id == site.StationId) is { } station)
        {
            return GetInventoryAmount(station.Inventory, itemId);
        }

        return GetInventoryAmount(site.DeliveredItems, itemId);
    }

    private static bool IsConstructionSiteReady(SimulationWorld world, ConstructionSiteRuntime site) =>
        site.RequiredItems.All(entry => GetConstructionDeliveredAmount(world, site, entry.Key) + 0.001f >= entry.Value);
}