/* eslint-disable no-process-exit */
require('babel-register');
require('dotenv').load();
const adler32 = require('adler32');
const { getChallenges } = require('@freecodecamp/curriculum');
const Rx = require('rxjs');
const _ = require('lodash');
const createDebugger = require('debug');

const utils = require('../utils');

const log = createDebugger('fcc:seed');
// force logger to always output
// this may be brittle
log.enabled = true;

const dasherize = utils.dasherize;
const nameify = utils.nameify;
const Observable = Rx.Observable;

const arrToString = arr =>
  Array.isArray(arr) ? arr.join('\n') : _.toString(arr);

exports.buildChallenges$ = function buildChallenges$() {
  return Observable.from(getChallenges()).map(function(challengeSpec) {
    const order = challengeSpec.order;
    const blockName = challengeSpec.name;
    const superBlock = challengeSpec.superBlock;
    const superOrder = challengeSpec.superOrder;
    const isBeta = !!challengeSpec.isBeta;
    const isComingSoon = !!challengeSpec.isComingSoon;
    const fileName = challengeSpec.fileName;
    const helpRoom = challengeSpec.helpRoom || 'Help';
    const time = challengeSpec.time;
    const isLocked = !!challengeSpec.isLocked;
    const message = challengeSpec.message;
    const required = challengeSpec.required || [];
    const template = challengeSpec.template;
    const isPrivate = !!challengeSpec.isPrivate;

    // challenge file has no challenges...
    if (challengeSpec.challenges.length === 0) {
      return Rx.Observable.of([{ block: 'empty ' + blockName }]);
    }

    const block = {
      title: blockName,
      name: nameify(blockName),
      dashedName: dasherize(blockName),
      superOrder,
      superBlock,
      superBlockMessage: message,
      order,
      time,
      isLocked,
      isPrivate
    };

    return challengeSpec.challenges.map(function(challenge, index) {
      challenge.name = nameify(challenge.title);

      challenge.dashedName = dasherize(challenge.name);

      challenge.checksum = adler32.sum(
        Buffer(
          challenge.title +
            JSON.stringify(challenge.description) +
            JSON.stringify(challenge.challengeSeed) +
            JSON.stringify(challenge.tests)
        )
      );

      if (challenge.files) {
        challenge.files = _.reduce(
          challenge.files,
          (map, file) => {
            map[file.key] = {
              ...file,
              head: arrToString(file.head),
              contents: arrToString(file.contents),
              tail: arrToString(file.tail)
            };
            return map;
          },
          {}
        );
      }
      challenge.fileName = fileName;
      challenge.helpRoom = helpRoom;
      challenge.order = order;
      challenge.suborder = index + 1;
      challenge.block = dasherize(blockName);
      challenge.blockId = block.id;
      challenge.isBeta = challenge.isBeta || isBeta;
      challenge.isComingSoon = challenge.isComingSoon || isComingSoon;
      challenge.isLocked = challenge.isLocked || isLocked;
      challenge.isPrivate = challenge.isPrivate || isPrivate;
      challenge.isRequired = !!challenge.isRequired;
      challenge.time = challengeSpec.time;
      challenge.superOrder = superOrder;
      challenge.superBlock = superBlock
        .split('-')
        .map(function(word) {
          return _.capitalize(word);
        })
        .join(' ');
      challenge.required = (challenge.required || []).concat(required);
      challenge.template = challenge.template || template;

      return _.omit(challenge, [
        'betaSolutions',
        'betaTests',
        'hints',
        'MDNlinks',
        'null',
        'rawSolutions',
        'react',
        'reactRedux',
        'redux',
        'releasedOn',
        'translations',
        'type'
      ]);
    });
  });
};