space-game/apps/backend/Simulation/Scenario/WorldBuilder.cs

using SpaceGame.Api.Data;
using SpaceGame.Api.Simulation.Model;
using static SpaceGame.Api.Simulation.LoaderSupport;

namespace SpaceGame.Api.Simulation;

internal sealed class WorldBuilder(
  WorldGenerationOptions worldGeneration,
  DataCatalogLoader dataLoader,
  SystemGenerationService generationService,
  SpatialBuilder spatialBuilder,
  WorldSeedingService seedingService)
{
  internal SimulationWorld Build()
  {
    var catalog = dataLoader.LoadCatalog();
    var systems = generationService.ExpandSystems(
      generationService.InjectSpecialSystems(catalog.AuthoredSystems),
      worldGeneration.TargetSystemCount);
    var scenario = dataLoader.NormalizeScenarioToAvailableSystems(
      catalog.Scenario,
      systems.Select(system => system.Id).ToList());

    var systemRuntimes = systems
      .Select(definition => new SystemRuntime
      {
        Definition = definition,
        Position = ToVector(definition.Position),
      })
      .ToList();
    var systemsById = systemRuntimes.ToDictionary(system => system.Definition.Id, StringComparer.Ordinal);
    var spatialLayout = spatialBuilder.BuildLayout(systemRuntimes, catalog.Balance);

    var stations = CreateStations(
      scenario,
      systemsById,
      spatialLayout.SystemGraphs,
      spatialLayout.Celestials,
      catalog.ModuleDefinitions);

    seedingService.InitializeStationStockpiles(stations);
    var refinery = seedingService.SelectRefineryStation(stations, scenario);
    var patrolRoutes = BuildPatrolRoutes(scenario, systemsById);
    var ships = CreateShips(scenario, systemsById, spatialLayout.Celestials, catalog.Balance, catalog.ShipDefinitions, patrolRoutes, refinery);

    var factions = seedingService.CreateFactions(stations, ships);
    seedingService.BootstrapFactionEconomy(factions, stations);
    var policies = seedingService.CreatePolicies(factions);
    var commanders = seedingService.CreateCommanders(factions, stations, ships);
    var nowUtc = DateTimeOffset.UtcNow;
    var claims = seedingService.CreateClaims(stations, spatialLayout.Celestials, nowUtc);
    var (constructionSites, marketOrders) = seedingService.CreateConstructionSites(stations, claims, catalog.ModuleRecipes);

    return new SimulationWorld
    {
      Label = "Split Viewer / Simulation World",
      Seed = WorldSeed,
      Balance = catalog.Balance,
      Systems = systemRuntimes,
      Celestials = spatialLayout.Celestials,
      Nodes = spatialLayout.Nodes,
      Stations = stations,
      Ships = ships,
      Factions = factions,
      Commanders = commanders,
      Claims = claims,
      ConstructionSites = constructionSites,
      MarketOrders = marketOrders,
      Policies = policies,
      ShipDefinitions = new Dictionary<string, ShipDefinition>(catalog.ShipDefinitions, StringComparer.Ordinal),
      ItemDefinitions = new Dictionary<string, ItemDefinition>(catalog.ItemDefinitions, StringComparer.Ordinal),
      ModuleDefinitions = new Dictionary<string, ModuleDefinition>(catalog.ModuleDefinitions, StringComparer.Ordinal),
      ModuleRecipes = new Dictionary<string, ModuleRecipeDefinition>(catalog.ModuleRecipes, StringComparer.Ordinal),
      Recipes = new Dictionary<string, RecipeDefinition>(catalog.Recipes, StringComparer.Ordinal),
      OrbitalTimeSeconds = WorldSeed * 97d,
      GeneratedAtUtc = DateTimeOffset.UtcNow,
    };
  }

  private static List<StationRuntime> CreateStations(
    ScenarioDefinition scenario,
    IReadOnlyDictionary<string, SystemRuntime> systemsById,
    IReadOnlyDictionary<string, SystemSpatialGraph> systemGraphs,
    IReadOnlyCollection<CelestialRuntime> celestials,
    IReadOnlyDictionary<string, ModuleDefinition> moduleDefinitions)
  {
    var stations = new List<StationRuntime>();
    var stationIdCounter = 0;

    foreach (var plan in scenario.InitialStations)
    {
      if (!systemsById.TryGetValue(plan.SystemId, out var system))
      {
        continue;
      }

      var placement = SpatialBuilder.ResolveStationPlacement(plan, system, systemGraphs[system.Definition.Id], celestials);
      var station = new StationRuntime
      {
        Id = $"station-{++stationIdCounter}",
        SystemId = system.Definition.Id,
        Label = plan.Label,
        Color = plan.Color,
        Position = placement.Position,
        FactionId = plan.FactionId ?? DefaultFactionId,
        CelestialId = placement.AnchorCelestial.Id,
      };

      stations.Add(station);
      placement.AnchorCelestial.OccupyingStructureId = station.Id;

      var startingModules = plan.StartingModules.Count > 0
        ? plan.StartingModules
        : ["module_arg_dock_m_01_lowtech", "module_gen_prod_energycells_01", "module_arg_stor_solid_m_01", "module_arg_stor_liquid_m_01"];

      foreach (var moduleId in startingModules)
      {
        AddStationModule(station, moduleDefinitions, moduleId);
      }
    }

    return stations;
  }

  private static Dictionary<string, List<Vector3>> BuildPatrolRoutes(
    ScenarioDefinition scenario,
    IReadOnlyDictionary<string, SystemRuntime> systemsById)
  {
    return scenario.PatrolRoutes
      .GroupBy(route => route.SystemId, StringComparer.Ordinal)
      .ToDictionary(
        group => group.Key,
        group => group
          .SelectMany(route => route.Points)
          .Select(point => NormalizeScenarioPoint(systemsById[group.Key], point))
          .ToList(),
        StringComparer.Ordinal);
  }

  private static List<ShipRuntime> CreateShips(
    ScenarioDefinition scenario,
    IReadOnlyDictionary<string, SystemRuntime> systemsById,
    IReadOnlyCollection<CelestialRuntime> celestials,
    BalanceDefinition balance,
    IReadOnlyDictionary<string, ShipDefinition> shipDefinitions,
    IReadOnlyDictionary<string, List<Vector3>> patrolRoutes,
    StationRuntime? refinery)
  {
    var ships = new List<ShipRuntime>();
    var shipIdCounter = 0;

    foreach (var formation in scenario.ShipFormations)
    {
      if (!shipDefinitions.TryGetValue(formation.ShipId, out var definition))
      {
        continue;
      }

      for (var index = 0; index < formation.Count; index += 1)
      {
        var offset = new Vector3((index % 3) * 18f, balance.YPlane, (index / 3) * 18f);
        var position = Add(NormalizeScenarioPoint(systemsById[formation.SystemId], formation.Center), offset);

        ships.Add(new ShipRuntime
        {
          Id = $"ship-{++shipIdCounter}",
          SystemId = formation.SystemId,
          Definition = definition,
          FactionId = formation.FactionId ?? DefaultFactionId,
          Position = position,
          TargetPosition = position,
          SpatialState = SpatialBuilder.CreateInitialShipSpatialState(formation.SystemId, position, celestials),
          DefaultBehavior = WorldSeedingService.CreateBehavior(definition, formation.SystemId, scenario, patrolRoutes, refinery),
          ControllerTask = new ControllerTaskRuntime { Kind = ControllerTaskKind.Idle, Threshold = balance.ArrivalThreshold, Status = WorkStatus.Pending },
          Health = definition.MaxHealth,
        });
      }
    }

    return ships;
  }
}