const App = (function () {
  let state = Storage.load();
  let currentLevelId = null;
  let levelHandle = null;
  let levelFinishing = false;

  function validateConfig() {
    const errors = [];
    const games = GAME_CONFIG.games;
    const expected = Levels.count;

    if (!Array.isArray(games) || games.length !== expected) {
      errors.push("er moeten precies " + expected + " games in GAME_CONFIG.games staan.");
    } else {
      games.forEach(function (game, index) {
        if (!game || !game.title) {
          errors.push("game " + (index + 1) + " heeft geen titel.");
          return;
        }
        if (!game.appId && !game.url && !game.key) {
          errors.push("game " + (index + 1) + " heeft geen appId, url of key.");
        }
      });
    }

    if (!GAME_CONFIG.herName) errors.push("de naam van de jarige ontbreekt.");
    return errors;
  }

  function init() {
    UI.init();
    UI.setState(state);
    UI.renderMap();
    UI.showScreen("welcome");

    const errors = validateConfig();
    if (errors.length > 0) {
      UI.showConfigError(errors);
    }
  }

  function destroyLevel() {
    if (levelHandle) {
      levelHandle.destroy();
      levelHandle = null;
    }
    currentLevelId = null;
    levelFinishing = false;
    UI.setHint("");
  }

  function goToMap() {
    destroyLevel();
    UI.renderMap();
    UI.showScreen("map");
  }

  function goHome() {
    if (currentLevelId !== null) {
      destroyLevel();
      UI.renderMap();
      UI.toast("Je kunt dit level later opnieuw doen.");
    }
    UI.showScreen("map");
  }

  function startLevel(id) {
    if (id < 1 || id > Levels.count) return;

    const completed = state.completed.indexOf(id) !== -1;
    if (id > state.unlocked && !completed) {
      UI.toast("Dit level is nog niet open.");
      return;
    }

    destroyLevel();
    currentLevelId = id;
    UI.showLevel(id);

    levelHandle = Levels.mount(id, document.getElementById("level-stage"), {
      hint: function (message) { UI.setHint(message); },
      onComplete: function () { finishLevel(id); }
    });
  }

  function finishLevel(id) {
    if (currentLevelId !== id || levelFinishing) return;
    levelFinishing = true;

    const firstTime = state.completed.indexOf(id) === -1;
    if (firstTime) {
      state.completed.push(id);
      state.completed.sort(function (a, b) { return a - b; });
      state.unlocked = Math.max(state.unlocked, Math.min(Levels.count, id + 1));
      Storage.save(state);
      UI.setState(state);
    }

    const gameIndex = id - 1;

    if (state.revealed.indexOf(gameIndex) === -1) {
      const markRevealed = function () {
        if (state.revealed.indexOf(gameIndex) !== -1) return;
        state.revealed.push(gameIndex);
        state.revealed.sort(function (a, b) { return a - b; });
        Storage.save(state);
        UI.setState(state);
      };

      UI.showReveal(gameIndex, function () {
        markRevealed();
        destroyLevel();
        UI.renderMap();

        if (state.completed.length === Levels.count && state.revealed.length === Levels.count) {
          UI.showFinale();
        } else {
          UI.showScreen("map");
        }
      }, { onSteamOpen: markRevealed });
      return;
    }

    destroyLevel();
    UI.renderMap();
    UI.toast(firstTime ? "Level voltooid!" : "Mooi opnieuw gedaan!");
    UI.showScreen("map");
  }

  function resetGame() {
    state = Storage.reset();
    destroyLevel();
    UI.setState(state);
    UI.renderMap();
    UI.showScreen("welcome");
    UI.toast("De tuin is opnieuw begonnen.");
  }

  return {
    init: init,
    goToMap: goToMap,
    goHome: goHome,
    startLevel: startLevel,
    resetGame: resetGame
  };
})();

App.init();