project-inter-server/src/resolvers/SystemResolvers.ts

import { Coordinates, Resolvers } from "../generated/graphql";
import { ServerContext } from "../ServerContext";

export const SystemResolvers: Resolvers<ServerContext> = {
  System: {
    routes: async (parent, args, contextValue, info) => {
      return await contextValue.repository.getRoutesBySystemId(parent.id);
    },
    stops: async (parent, args, contextValue, info) => {
      const stops = await contextValue.repository.getStopsBySystemId(parent.id);
      return stops.map(({
                          id,
                          name,
                          coordinates
                        }) => ({
        id,
        name,
        // Both ICoordinates and Coordinates have the same definition
        coordinates: coordinates as Coordinates,
      }));
    },
    stop: async (parent, args, contextValue, info) => {
      if (!args.id) return null;
      const stop = await contextValue.repository.getStopById(args.id);
      if (stop === null) return null;

      return {
        id: stop.id,
        name: stop.name,
        coordinates: stop.coordinates as Coordinates,
      };
    },
    route: async (parent, args, contextValue, info) => {
      if (!args.id) return null;
      const route = await contextValue.repository.getRouteById(args.id);
      if (route === null) return null;

      return {
        color: route.color,
        id: route.id,
        name: route.name,
        polylineCoordinates: route.polylineCoordinates as Coordinates[],
      };
    },
    shuttle: async (parent, args, contextValue, info) => {
      if (!args.id) return null;
      const shuttle = await contextValue.repository.getShuttleById(args.id);
      if (shuttle === null) return null;

      return shuttle;
    },
    shuttles: async (parent, args, contextValue, info) => {
      const shuttles = await contextValue.repository.getShuttlesBySystemId(parent.id);

      return shuttles.map(shuttle => ({
        coordinates: shuttle.coordinates,
        name: shuttle.name,
        id: shuttle.id,
        routeId: shuttle.routeId,
      }));
    }
  },
}