game engine.js

import { Map, List } from "immutable";

// createStory :: String -> Option -> Option -> Option -> Artifact -> Story
const createStory = (
  storyText,
  option1,
  option2,
  option3,
  requiredArtifact = null
) =>
  Map({
    text: storyText,
    one: option1,
    two: option2,
    three: option3,
    requiredArtifact: requiredArtifact
  });

// createChoice :: String -> (GameState -> (String, GameState)) -> String -> Choice
const createChoice = (text, fn, resolutionText) =>
  Map({ text: text, fn: fn, resolutionText: resolutionText });

// addStory :: Story -> GameState -> GameState
const addStory = (story, gameState) =>
  gameState.updateIn(["stories"], l => l.push(story));

// addArtifact :: Artifact -> GameState -> GameState
const addArtifact = (artifact, gameState) =>
  gameState.updateIn(["artifacts"], l => l.push(artifact));

// hasArtifact :: Artifact -> GameState -> Bool
const hasArtifact = (artifact, gameState) =>
  gameState.get("artifacts").includes(artifact);

// initGameState :: () -> GameState
const initGameState = () => new Map({ stories: List(), artifacts: List() });

// nextStory :: GameState -> (Story, GameState)
const nextStory = gameState => {
  const filtered = gameState.get("stories").filter(s => {
    const ra = s.get("requiredArtifact");
    return ra === null || gameState.get("artifacts").includes(ra);
  });

  const index = Math.floor(Math.random() * filtered.size);
  const selected = filtered.get(index);
  const newGameState = gameState.updateIn(["stories"], l => l.delete(index));

  return { selected, newGameState };
};

const s1 = createStory(
  "Du befinner dig i templet. Du hör hur munkarna kommer. Du har bara tid att plocka en av sakerna. Vilken väljer du?",
  createChoice("Du tar kniven", s => {
    const s2 = addArtifact("Knivs", s);
    return {
      resolution: "Du stoppar kiven inannför västen, känns som ett bra val",
      gameState: s2
    };
  }),
  createChoice("Du tar bägaren", s => {
    const s2 = addArtifact("Bägare", s);
    return {
      resolution: "vad skall man ens med en sådan här till?",
      gameState: s2
    };
  }),
  createChoice("Du springer", s => {
    return { resolution: "Mmmm fegis", gameState: s };
  })
);

const s2 = createStory(
  "Med kniven i handen har du all makt över hennes liv vad gör du?",
  createChoice("Skär av henne håret", s => {
    const s2 = addArtifact("Jagad", s);
    return {
      resolution:
        "Du hör hur någon bankar in dörren. Du hinner just ut men du känner dig inte trygg. Vad har du gjort",
      gameState: s2
    };
  }),
  createChoice("Skär henne i foten", s => {
    const s2 = addArtifact("Fot", s);
    return { resolution: "Utan fötter kan man inte göra något", gameState: s2 };
  }),
  createChoice("Skär henne i tungan", s => {
    const s2 = addArtifact("Tunga", s);
    const s3 = addStory(sTunga, s2);
    return { resolution: "Ännu ett smart val!", gameState: s3 };
  }),
  "Kniv"
);

const sTunga = createStory(
  "Opium och torkad tunga. Det är tidens melodi",
  createChoice("Väääässs", s => ({
    resolution: "Du känner giftet i blodet",
    gameState: s
  })),
  createChoice("Vyyys", s => ({
    resolution: "Du känner kraften i blodet",
    gameState: s
  })),
  createChoice("MMmppfff", s => ({
    resolution: "Du har inget blod",
    gameState: s
  }))
);

const s3 = createStory(
  "Du fumlar genom mörkret men vad är det du ser?",
  createChoice("En kentaur", s => ({
    resolution: "Dom här kan man slåss med",
    gameState: s
  })),
  createChoice("En orm", s => ({ resolution: "Dom här ger en styrka", s })),
  createChoice("En man i blått", s => {
    if (hasArtifact("Jagad", s)) {
      const s2 = addArtifact("Död", s);
      return { resolution: "Mannen skjuter dig i huvudet", gameState: s2 };
    } else {
      return { resolution: "Ingen du känner", gameState: s };
    }
  })
);

// printStory :: Story -> ()
const printStory = s => {
  console.log(s.get("text"));
  console.log("1: " + s.get("one").text);
  console.log("2: " + s.get("two").text);
  console.log("3: " + s.get("three").text);
};

// printResolution :: String -> ()
const printResolution = resolution => console.log(resolution);

const gs1 = initGameState();
const gs2 = addStory(s1, gs1);
const gs3 = addStory(s2, gs2);
const gs4 = addStory(s3, gs3);

// Game loop

// Select story
const { selected: s, newGameState: gs5 } = nextStory(gs4);

// Print
printStory(s);

// Select and resolve
const { resolution: r, gameState: gs6 } = s.get("two").get("fn")(gs5);

// print resolution
printResolution(r);

// Kör igen med gs6 som gamestate istälet för gs4