#!/usr/bin/env node
'use strict';

/* eslint-disable no-console */

const fs = require('fs');
const getChannelURL = require('../src');
const channel = process.argv[2];
const shouldUpdatePackage = process.argv.includes('-w') || process.argv.includes('--write');
const DETECT_TRAILING_WHITESPACE = /\s+$/;

function printUsage() {
  console.log(`
ember-source-channel-url is a utility module to easily obtain the URL
to a tarball representing the latest \`ember-source\` build for a given
channel.

USAGE:
  ember-source-channel-url [CHANNEL] [FLAGS]

FLAGS:

  -w, --write   Update the local package.json to use the retrieved ember-source URL
  -h, --help    Prints help information

EXAMPLE:

  * Print the most recent URL for the specified channel:

    $ ember-source-channel-url canary
    $ ember-source-channel-url beta
    $ ember-source-channel-url release

  * Update the local project's \`package.json\` to use the most recent URL for the canary channel:

    $ ember-source-channel-url canary --write
`);
}

if (['release', 'beta', 'canary'].indexOf(channel) === -1) {
  printUsage();
  process.exitCode = 1;
} else {
  getChannelURL(channel).then(url => {
    if (process.stdout.isTTY) {
      console.log(
        `The URL for the latest tarball from ember-source's ${channel} channel is:\n\n\t${url}\n`
      );
    } else {
      process.stdout.write(url);
    }

    if (shouldUpdatePackage) {
      if (!fs.existsSync('package.json')) {
        console.log(
          `You passed --write to ember-source-channel-url but no package.json is available to update.`
        );

        process.exitCode = 2;
      }

      let contents = fs.readFileSync('package.json', { encoding: 'utf8' });
      let trailingWhitespace = DETECT_TRAILING_WHITESPACE.exec(contents);
      let pkg = JSON.parse(contents);

      let dependencyType = ['dependencies', 'devDependencies'].find(
        type => pkg[type] && pkg[type]['ember-source']
      );

      if (dependencyType) {
        pkg[dependencyType]['ember-source'] = url;

        let updatedContents = JSON.stringify(pkg, null, 2);

        if (trailingWhitespace) {
          updatedContents += trailingWhitespace[0];
        }

        fs.writeFileSync('package.json', updatedContents, { encoding: 'utf8' });
      } else {
        console.log(
          `You passed --write to ember-source-channel-url but ember-source is not included in dependencies or devDependencies in the package.json.`
        );

        process.exitCode = 3;
      }
    }
  });
}