import shopifyAuth, {verifyRequest} from '@shopify/koa-shopify-auth';
import Shopify, {ApiVersion} from '@shopify/shopify-api';

// Initialize the library
Shopify.Context.initialize({
  API_KEY: 'Your API_KEY',
  API_SECRET_KEY: 'Your API_SECRET_KEY',
  SCOPES: ['Your scopes'],
  HOST_NAME: 'Your HOST_NAME (omit the https:// part)',
  API_VERSION: ApiVersion.October20,
  IS_EMBEDDED_APP: true,
  // More information at https://github.com/Shopify/shopify-node-api/blob/main/docs/issues.md#notes-on-session-handling
  SESSION_STORAGE: new Shopify.Session.MemorySessionStorage(),
});

app.use(
  shopifyAuth({
    // if specified, mounts the routes off of the given path
    // eg. /shopify/auth, /shopify/auth/callback
    // defaults to ''
    prefix: '/shopify',
    // set access mode, default is 'online'
    accessMode: 'offline',
    // callback for when auth is completed
    afterAuth(ctx) {
      const {shop, accessToken} = ctx.state.shopify;

      console.log('We did it!', accessToken);

      ctx.redirect('/');
    },
  }),
);

app.use(
  verifyRequest({
    // path to redirect to if verification fails
    // defaults to '/auth'
    authRoute: '/foo/auth',
    // path to redirect to if verification fails and there is no shop on the query
    // defaults to '/auth'
    fallbackRoute: '/install',
    // which access mode is being used
    // defaults to 'online'
    accessMode: 'offline',
    // if false, redirect the user to OAuth. If true, send back a 403 with the following headers:
    //  - X-Shopify-API-Request-Failure-Reauthorize: '1'
    //  - X-Shopify-API-Request-Failure-Reauthorize-Url: '<auth_url_path>'
    // defaults to false
    returnHeader: true,
  }),
);

import 'isomorphic-fetch';

import Koa from 'koa';
import Router from 'koa-router';
import shopifyAuth, {verifyRequest} from '@shopify/koa-shopify-auth';
import Shopify, {ApiVersion} from '@shopify/shopify-api';

// Loads the .env file into process.env. This is usually done using actual environment variables in production
import dotenv from 'dotenv';
dotenv.config();

const port = parseInt(process.env.PORT, 10) || 8081;

// initializes the library
Shopify.Context.initialize({
  API_KEY: process.env.SHOPIFY_API_KEY,
  API_SECRET_KEY: process.env.SHOPIFY_API_SECRET,
  SCOPES: process.env.SHOPIFY_APP_SCOPES,
  HOST_NAME: process.env.SHOPIFY_APP_URL.replace(/^https:\/\//, ''),
  API_VERSION: ApiVersion.October20,
  IS_EMBEDDED_APP: true,
  // More information at https://github.com/Shopify/shopify-node-api/blob/main/docs/issues.md#notes-on-session-handling
  SESSION_STORAGE: new Shopify.Session.MemorySessionStorage(),
});

// Storing the currently active shops in memory will force them to re-login when your server restarts. You should
// persist this object in your app.
const ACTIVE_SHOPIFY_SHOPS = {};

const app = new Koa();
const router = new Router();
app.keys = [Shopify.Context.API_SECRET_KEY];

// Sets up shopify auth
app.use(
  shopifyAuth({
    async afterAuth(ctx) {
      const {shop, accessToken} = ctx.state.shopify;
      ACTIVE_SHOPIFY_SHOPS[shop] = true;

      // Your app should handle the APP_UNINSTALLED webhook to make sure merchants go through OAuth if they reinstall it
      const response = await Shopify.Webhooks.Registry.register({
        shop,
        accessToken,
        path: '/webhooks',
        topic: 'APP_UNINSTALLED',
        webhookHandler: async (topic, shop, body) =>
          delete ACTIVE_SHOPIFY_SHOPS[shop],
      });

      if (!response['APP_UNINSTALLED'].success) {
        console.log(
          `Failed to register APP_UNINSTALLED webhook: ${response['APP_UNINSTALLED'].result}`,
        );
      }

      // Redirect to app with shop parameter upon auth
      ctx.redirect(`/?shop=${shop}`);
    },
  }),
);

router.get('/', async (ctx) => {
  const shop = ctx.query.shop;

  // If this shop hasn't been seen yet, go through OAuth to create a session
  if (ACTIVE_SHOPIFY_SHOPS[shop] === undefined) {
    ctx.redirect(`/auth?shop=${shop}`);
  } else {
    // Load app skeleton. Don't include sensitive information here!
    ctx.body = '🎉';
  }
});

router.post('/webhooks', async (ctx) => {
  try {
    await Shopify.Webhooks.Registry.process(ctx.req, ctx.res);
    console.log(`Webhook processed, returned status code 200`);
  } catch (error) {
    console.log(`Failed to process webhook: ${error}`);
  }
});

// Everything else must have sessions
router.get('(.*)', verifyRequest(), async (ctx) => {
  // Your application code goes here
});

app.use(router.allowedMethods());
app.use(router.routes());
app.listen(port, () => {
  console.log(`> Ready on http://localhost:${port}`);
});