#!/usr/bin/env node

/* Auxiliary script that helps to install and upgrade Topcoder libraries
 * published to NPM. */
/* eslint-disable import/no-extraneous-dependencies, no-console  */

const commandLineArgs = require('command-line-args');
const commandLineUsage = require('command-line-usage');
const fs = require('fs');
const path = require('path');
const { spawnSync } = require('child_process');

/* Definition of command-line arguments. */
const OPTIONS = [{
  name: 'help',
  alias: 'h',
  description: 'Shows usage instructions',
  type: Boolean,
}, {
  name: 'just-fix-deps',
  description: 'Skips installation of libraries, just fixes dependencies',
  type: Boolean,
}, {
  name: 'libraries',
  defaultOption: true,
  multiple: true,
  type: String,
}];

/* Definition of help information. */
const HELP = [{
  content: 'Usage: {cyanBright topcoder-lib-setup [OPTION]... LIBRARY...}',
}, {
  header: 'Description',
  content:
    `Installs or upgrades Topcoder's ReactJS libraries released to NPM.
    {cyanBright [OPTION]...} is the list of options (see below);
    {cyanBright LIBRARY...} is the list of libraries to install/upgrade`,
}, {
  header: 'Options',
  optionList: OPTIONS.filter(x => !x.defaultOption),
}];

/**
 * Generates a string containing name and version of the package to be
 * installed.
 * @param {Array} entry Array with package name as the first element, and
 *  corresponding version or URI given in a `package.json`.
 * @return {String} Package name and version as a string that can be passed
 *  into NPM's install command.
 */
function generateTargetPackage(entry) {
  if (entry[1].match(/^(git\+)?(file|https)?:\/\//)) return entry[1];
  if (entry[1].match(/^[\^~]/)) return `${entry[0]}@${entry[1].slice(1)}`;
  return `${entry[0]}@${entry[1]}`;
}

/**
 * Adopts dev dependencies of the `donor` package into the `host` one.
 * @param {Object} donorData Data from donor's `package.json`.
 * @param {Object} hostData Data from host's `package.json`.
 */
function adoptDevDependencies(donorData) {
  let deps = Object.entries(donorData.devDependencies || {});
  deps = deps.map(generateTargetPackage);
  spawnSync('npm', ['install', '--save-dev'].concat(deps), {
    stdio: 'inherit',
  });
}

/**
 * Locates and loads `package.json` of the host package (assumed to be inside
 * the current working directory).
 * @return {Object} Data from `package.json` parsed into JSON.
 */
function getHostPackageJson() {
  const url = path.resolve(process.cwd(), 'package.json');
  return JSON.parse(fs.readFileSync(url));
}

/**
 * Locates and loads `package.json` file of the specified package.
 * @param {String} package Package name.
 * @return {Object} Data from `package.json` parsed into JSON.
 */
function getPackageJson(packageName = 'topcoder-react-utils') {
  let url = packageName === 'topcoder-react-utils' ? '..' : packageName;
  url = path.dirname(require.resolve(url));
  for (;;) {
    const files = fs.readdirSync(url);
    if (files.includes('package.json')) {
      url = path.resolve(url, 'package.json');
      break;
    }
    const up = path.resolve(url, '..');
    if (url === up) throw new Error(`Cannot find the package ${packageName}`);
    url = up;
  }
  return JSON.parse(fs.readFileSync(url));
}

/**
 * Installs specified library.
 * @param {String} library Library name.
 */
function install(library) {
  let name = library;
  if (name.indexOf('@') <= 0) name += '@latest';
  spawnSync('npm', ['install', '--save', name], { stdio: 'inherit' });
}

/**
 * Outputs help information to console.
 */
function showHelp() {
  console.log(commandLineUsage(HELP));
}

/**
 * Updates prod dependencies of `host` package that are also prod dependencies
 * of `donor` to the same versions specified in the donor's `package.json`.
 * @param {Object} donorData Data from donor's `package.json`.
 * @param {Object} hostData Data from host's `package.json`.
 */
function updateProdDependencies(donorData, hostData) {
  let deps = Object.entries(donorData.dependencies || {});
  const hostDeps = hostData.dependencies || {};
  deps = deps.filter(x => hostDeps[x[0]]);
  deps = deps.map(generateTargetPackage);
  spawnSync('npm', ['install', '--save'].concat(deps), { stdio: 'inherit' });
}

/* Entry point. */

const options = commandLineArgs(OPTIONS);
if (!options.libraries) {
  options.libraries = ['topcoder-react-utils'];
}

if (options.help) showHelp();
else {
  const hostData = getHostPackageJson();
  options.libraries.forEach((library) => {
    if (!options['just-fix-deps']) install(library);
    const libData = getPackageJson(library);
    adoptDevDependencies(libData, hostData);
    updateProdDependencies(libData, hostData);
  });
  spawnSync('npm', ['install'], { stdio: 'inherit' });
}