number-munchers/js/app/Reducers.js

import { MODE, VALUES, BLINK, MUNCHER } from './Constants.js';

import { Values } from '../board/Values';
import { GRID } from './Settings';

export const modeReducer = (state = MODE.WELCOME, action) => {
    if (action.type === MODE.NEXT) {
        switch (state) {
            case MODE.BOARD:
                return MODE.WELCOME;
            case MODE.WELCOME:
                return MODE.BOARD;
        };
    }

    return MODE.BOARD;
};

export const blinkReducer = (state = false, action) => {
    if (action.type === BLINK.TOGGLE) {
        return (state ? false : true);
    }

    return state;
};

export const valuesReducer = (state = [], action) => {
    if (action.type === VALUES.FOO) {
        switch (action.action) {
            case VALUES.GENERATE:
                return Values.generate(action.count, action.level);
            case VALUES.UPDATE:
                const valid = Values.validate(state[action.index], action.level);
                const results = state.slice(0);
                if (valid) {
                    results[action.index] = "";
                }
                return results;
        }
    }

    return state;
};

const muncherInitialState = { x: 0, y: 0 };
export const muncherReducer = (state = muncherInitialState, action) => {
    if (action.type === MUNCHER.MOVE) {
        switch (action.direction) {
            case MUNCHER.LEFT:
                return (state.x > 0 ? { x: state.x - 1, y: state.y } : state);
            case MUNCHER.RIGHT:
                return (state.x < GRID.W - 1 ? { x: state.x + 1, y: state.y } : state);
            case MUNCHER.UP:
                return (state.y > 0 ? { x: state.x, y: state.y - 1 } : state);
            case MUNCHER.DOWN:
                return (state.y < GRID.H - 1 ? { x: state.x, y: state.y + 1 } : state);
            };
        }

        return state;
    };