const fs = require('fs-extra');
const path = require('path');
const btoa = require('btoa');
const { version } = require(path.join(__dirname, '..', 'package.json'));
const _ = require('lodash');
const github = require('@octokit/rest')({
  // GitHub personal access token
  auth: process.env.github_token,
  // User agent with version from package.json
  userAgent: `mit-license v${version}`,
});
const { validDomainId } = require('./utils');

function getUserData({ query, body }) {
  // If query parameters provided
  if (_.size(query) > 0) return query;
  // If the data parsed as {'{data: "value"}': ''}
  if (_.size(body) === 1 && !_.first(_.values(body))) return JSON.parse(_.first(_.keys(body)));
  // Fallback
  return body;
}

// HTTP POST API
module.exports = async (req, res) => {
  const { hostname } = req;
  // Get different parts of hostname (example: remy.mit-license.org -> ['remy', 'mit-license', 'org'])
  const params = hostname.split('.');

  // This includes the copyright, year, etc.
  const userData = getUserData(req);

  // If there isn't enough part of the hostname
  if (params.length < 2) {
    res.status(400).send('Please specify a subdomain in the URL.');
    return;
  }

  // Extract the name from the URL
  const id = _.first(params);

  if (!validDomainId(id)) {
    // Return a vague error intentionally
    res
      .status(400)
      .send(
        'User already exists - to update values, please send a pull request on https://github.com/remy/mit-license'
      );

    return;
  }

  // Check if the user file exists in the users directory
  const exists = await fs.pathExists(path.join(__dirname, '..', 'users', `${id}.json`));
  if (exists) {
    res
      .status(409)
      .send(
        'User already exists - to update values, please send a pull request on https://github.com/remy/mit-license'
      );
    return;
  }

  // File doesn't exist
  // If copyright property and key doesn't exist
  if (!userData.copyright) {
    res.status(400).send('JSON requires "copyright" property and value');
    return;
  }

  try {
    const fileContent = JSON.stringify(userData, 0, 2);

    await github.repos.createOrUpdateFile({
      owner: 'remy',
      repo: 'mit-license',
      path: `users/${id}.json`,
      message: `chore: Automated creation of user ${id}.`,
      content: btoa(fileContent),
      committer: {
        name: 'MIT License Bot',
        email: 'remy@leftlogic.com',
      },
    });

    await fs.writeFile(path.join(__dirname, '..', 'users', `${id}.json`), fileContent);

    res.status(201).send(`MIT license page created: https://${hostname}`);
  } catch (err) {
    res
      .status(500)
      .send(
        `Unable to create new user - please send a pull request on https://github.com/remy/mit-license`
      );
  }
};