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

export const OrderedStopResolvers: Resolvers<ServerContext> = {
  OrderedStop: {
    nextStop: async (parent, args, contextValue, _info): Promise<OrderedStop | null> => {
      const routeId = parent.routeId;
      const stopId = parent.stopId;

      if (!parent.stop) return null;
      const system = contextValue.findSystemById(parent.stop.systemId);
      if (!system) return null;

      const currentOrderedStop = await system.shuttleRepository.getOrderedStopByRouteAndStopId(routeId, stopId);
      if (!currentOrderedStop) return null;

      const nextOrderedStop = currentOrderedStop.nextStop;
      if (!nextOrderedStop) return null;

      const nextOrderedStopObject = await system.shuttleRepository.getStopById(nextOrderedStop.stopId);
      if (!nextOrderedStopObject) return null;

      return {
        route: parent.route,
        routeId: parent.routeId,
        stopId: nextOrderedStopObject.id,
      }
    },
    previousStop: async (parent, args, contextValue, _info): Promise<OrderedStop | null> => {
      const routeId = parent.routeId;
      const stopId = parent.stopId;

      if (!parent.stop) return null;
      const system = contextValue.findSystemById(parent.stop.systemId);
      if (!system) return null;

      const currentOrderedStop = await system.shuttleRepository.getOrderedStopByRouteAndStopId(routeId, stopId);
      if (!currentOrderedStop) return null;

      const previousOrderedStop = currentOrderedStop.previousStop;
      if (!previousOrderedStop) return null;

      const previousOrderedStopObject = await system.shuttleRepository.getStopById(previousOrderedStop.stopId);
      if (!previousOrderedStopObject) return null;

      return {
        route: parent.route,
        routeId: parent.routeId,
        stopId: previousOrderedStopObject.id,
      }
    },
    stop: async (parent, args, contextValue, _info) => {
      if (!parent.stop) return null;
      const system = contextValue.findSystemById(parent.stop.systemId);
      if (!system) return null;

      return await system.shuttleRepository.getStopById(parent.stopId);
    },
    route: async (parent, args, contextValue, _info) => {
      if (!parent.stop) return null;
      const system = contextValue.findSystemById(parent.stop.systemId);
      if (!system) return null;

      return await system.shuttleRepository.getRouteById(parent.routeId);
    },
  },

}