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AI Dungeon Game

Module 4: UI implementation

To start building the UI, we want to configure our local dev server to point to our deployed sandbox. To do this, run the following command:

Terminal window
pnpm nx run @dungeon-adventure/game-ui:load:runtime-config

This command will pull down the runtime-config.json that is deployed and store it locally within the packages/game-ui/public folder.

Now we can start the dev server with the following command:

Terminal window
pnpm nx run @dungeon-adventure/game-ui:serve

You can then open up your local website in a browser at which time you will be prompted to log in and follow the prompts to create a new user. Once completed you should see the baseline website:

baseline-website.png

Create a new ‘/game’ route

Let’s showcase the capabilities of @tanstack/react-router by creating a new type-safe route. To do this, simply create an empty file at the following location: packages/game-ui/src/routes/game/index.tsx. Pay close attention to the dev server logs:

Terminal window
♻️  Regenerating routes...
🟡 Updating /Users/dimecha/dungeon-adventure/packages/game-ui/src/routes/game/index.tsx
🟡 Updating /Users/dimecha/dungeon-adventure/packages/game-ui/src/routeTree.gen.ts
✅ Processed routes in 27ms

The @tanstack/react-router automatically has configured your new route and you will notice that the file you just created is already populated with the route path:

import { createFileRoute } from '@tanstack/react-router'


export const Route = createFileRoute('/game/')({
  component: RouteComponent,
})


function RouteComponent() {
  return <div>Hello "/game/"!</div>
}

Now if you navigate to http://localhost:4200/game you will see your new page has been rendered!

baseline-game.png

Let’s also update the index.tsx file to load our new /game route by default. Notice how when you update the to field, you have a list of type-safe routes to choose from.

import { createFileRoute, Navigate } from '@tanstack/react-router';


export const Route = createFileRoute('/')({
  component: () => <Navigate to="/game" />,
});

Finally we can delete the packages/game-ui/src/routes/welcome/ folder as this is no longer required.

Layout updates

The default layout that is configured is more akin to a SaaS style business application than a game. We are going to re-configure the layout and re-theme it to be more akin to a dungeon style game.

Let’s make the following changes to packages/game-ui/src:

export default {
  applicationName: 'Dungeon Adventure',
};

Now let’s delete the packages/game-ui/src/components/AppLayout/navitems.ts and packages/game-ui/src/hooks/useAppLayout.tsx files as they are unused.

Game pages

Let’s create the Game pages which will call our APIs and finish our game implementation:

import { FormField, Spinner } from '@cloudscape-design/components';
import { useInfiniteQuery, useMutation } from '@tanstack/react-query';
import { createFileRoute, useNavigate } from '@tanstack/react-router';
import {
  createRef,
  LegacyRef,
  MutableRefObject,
  useEffect,
  useMemo,
  useState,
} from 'react';
import { useGameApi } from '../../hooks/useGameApi';
import { IAction, IGame } from ':dungeon-adventure/game-api-schema';


type IGameState = Omit<IGame, 'lastUpdated'> & { actions: IAction[] };


export const Route = createFileRoute('/game/')({
  component: RouteComponent,
});


// hook to check if a ref is visible on the screen
export function useIsVisible(ref: MutableRefObject<any>) {
  const [isIntersecting, setIntersecting] = useState(false);


  useEffect(() => {
    const observer = new IntersectionObserver(([entry]) =>
      setIntersecting(entry.isIntersecting),
    );


    ref.current && observer.observe(ref.current);
    return () => {
      observer.disconnect();
    };
  }, [ref]);


  return isIntersecting;
}


function RouteComponent() {
  const [playerName, setPlayerName] = useState('');
  const navigate = useNavigate();
  const ref = createRef();
  const isLastGameVisible = useIsVisible(ref);


  const gameApi = useGameApi();
  const saveGameMutation = useMutation(gameApi.games.save.mutationOptions());


  const {
    data: gamesPages,
    fetchNextPage,
    hasNextPage,
    isFetchingNextPage,
  } = useInfiniteQuery(
    gameApi.games.query.infiniteQueryOptions(
      { limit: 10 },
      { getNextPageParam: ({ cursor }) => cursor },
    ),
  );
  const games = useMemo(() => {
    return gamesPages?.pages.flatMap((page) => page.items) || [];
  }, [gamesPages]);


  // Fetch more games if the last game is visible and there are more games
  useEffect(() => {
    if (isLastGameVisible && hasNextPage && !isFetchingNextPage) {
      fetchNextPage();
    }
  }, [isFetchingNextPage, hasNextPage, fetchNextPage, isLastGameVisible]);


  const playerAlreadyExists = (playerName?: string) => {
    return !!games?.find((s) => s.playerName === playerName);
  };


  // create a new game
  const handleStartGame = async (
    playerName: string,
    genre: IGameState['genre'],
  ) => {
    if (playerAlreadyExists(playerName)) {
      return;
    }
    try {
      await saveGameMutation.mutateAsync({
        playerName,
        genre,
      });


      await handleLoadGame(playerName, genre);
    } catch (error) {
      console.error('Failed to start game:', error);
    }
  };


  // load an existing game
  const handleLoadGame = async (
    playerName: string,
    genre: IGameState['genre'],
  ) => {
    await navigate({
      to: '/game/$playerName',
      params: { playerName },
      search: { genre },
    });
  };


  return (
    <div className="game-interface">
      <header className="game-header">
        <h1>AI Dungeon Adventure</h1>
      </header>


      {/* New Game Section */}
      <div className="new-game">
        <h2>Start New Game</h2>
        <div className="game-setup">
          <FormField
            errorText={
              playerAlreadyExists(playerName)
                ? `${playerName} already exists`
                : undefined
            }
          >
            <input
              type="text"
              placeholder="Enter your name"
              className="name-input"
              onChange={(e) => setPlayerName(e.target.value)}
              onKeyDown={(e) => {
                if (e.key === 'Enter') {
                  const input = e.currentTarget;
                  handleStartGame(input.value, 'medieval');
                }
              }}
            />
          </FormField>
          <div className="genre-grid">
            {(['zombie', 'superhero', 'medieval'] as const).map((genre) => (
              <button
                key={genre}
                className="genre-button"
                onClick={() => {
                  const playerName = document.querySelector('input')?.value;
                  if (playerName) {
                    handleStartGame(playerName, genre);
                  }
                }}
              >
                {genre.charAt(0).toUpperCase() + genre.slice(1)}
              </button>
            ))}
          </div>
        </div>
      </div>


      {/* Saved Games Section */}
      {games && games.length > 0 && (
        <div className="saved-games">
          <h2>Continue Game</h2>
          <div className="game-list">
            {games.map((game, idx) => (
              <button
                key={game.playerName}
                ref={
                  idx === games.length - 1
                    ? (ref as LegacyRef<HTMLButtonElement>)
                    : undefined
                }
                onClick={() => handleLoadGame(game.playerName, game.genre)}
                className="game-session"
              >
                <div className="player-name">{game.playerName}</div>
                <div className="genre-name">
                  {game.genre.charAt(0).toUpperCase() + game.genre.slice(1)}
                </div>
              </button>
            ))}
            {isFetchingNextPage && <Spinner data-style="generating" size="big" />}
          </div>
        </div>
      )}
    </div>
  );
}

Once you make these changes, your local dev server (http://localhost:4200/) should now have your game ready to play!

You can also build & deploy your code to Cloudfront if you prefer.
game-select.png
game-conversation.png

Congratulations. You have built and deployed your Dungeon Adventure Game! 🎉🎉🎉