import-firestore.js

import { remoteConfig } from './index';

const admin = require('../functions/node_modules/firebase-admin');
const _ = require('../functions/node_modules/lodash');

const serviceAccount = require('../configs//firebase/service-key.development.json');

admin.initializeApp({
  credential: admin.credential.cert(serviceAccount),
  // databaseURL: "https://<your-database-name>.firebaseio.com"
});

/**
 * Data is a collection if
 *  - it has a odd depth
 *  - contains only objects or contains no objects.
 */
function isCollection(data) {
  let isCollectionFlag = true;

  if (
    typeof data !== 'object' ||
    _.isEmpty(data)
  ) {
    isCollectionFlag = false;
  }

  Object.keys(data).forEach((key) => {
    if (typeof data[key] !== 'object' || data[key] == null) {
      // If there is at least one non-object item i its data then it cannot be collection.
      isCollectionFlag = false;
    }
  });

  return isCollectionFlag;
}

function upload(data, path) {
  return admin.firestore()
    .doc(path.join('/'))
    .set(data)
    .then(() => console.log(`Document ${path.join('/')} uploaded.`))
    .catch(() => console.error(`Could not write document ${path.join('/')}.`));
}

/**
 *
 */
async function resolve(data, path = []) {
  if (path.length > 0 && path.length % 2 === 0) {
    // Document's length of path is always even, however, one of keys can actually be a collection.

    // Copy an object.
    const documentData = Object.assign({}, data);
    Object.keys(data).forEach((key) => {
      // Resolve each collection and remove it from document data.
      if (isCollection(data[key])) {
        // Remove a collection from the document data.
        delete documentData[key];
        // Resolve a colleciton.
        resolve(data[key], [...path, key]);
      }
    });

    // If document is empty then it means it only consisted of collections.
    if (!_.isEmpty(documentData)) {
      // Upload a document free of collections.
      await upload(documentData, path);
    }
  } else {
    // Collection's length of is always odd.
    Object.keys(data).forEach(async (key) => {
      // Resolve each collection.
      await resolve(data[key], [...path, key]);
    });
  }
}

resolve({
  remoteConfig,
});