/*
 * Copyright (C) Sapphirecode - All Rights Reserved
 * This file is part of Snippeteer which is released under BSD-3-Clause.
 * See file 'LICENSE' for full license details.
 * Created by Timo Hocker <timo@scode.ovh>, March 2020
 */



/* eslint-disable no-sync */
/* eslint-disable no-console */
/* eslint-disable no-await-in-loop */

'use strict';

const fs = require ('fs-extra');
const path = require ('path');

/**
 * scan all files and execute a mutation on them
 *
 * @param {string} folder folder to scan
 * @param {Function} func function to execute on file contents
 */
async function map_all_files (folder, func) {
  const files = await fs.readdir (folder);
  for (const file of files) {
    if ([ 'node_modules' ].includes (file))
      continue;
    const abs_path = path.join (folder, file);
    if ((await fs.stat (abs_path)).isDirectory ()) {
      map_all_files (abs_path, func);
      continue;
    }
    const data = await fs.readFile (abs_path, 'utf-8');
    const res = func (data, file);
    if (res === null)
      continue;
    await fs.writeFile (abs_path, res, 'utf-8');
  }
}

/**
 * returns a copyright notice
 *
 * @param {string} license license name
 * @param {string} software software name
 * @returns {string} copyright notice
 */
function get_copyright_notice (license = '', software = '') {
  let notice = '';
  const date = (new Date);
  const dtf = new Intl.DateTimeFormat ('en', { month: 'long' });
  const year = date.getFullYear ();
  const month = dtf.format (date);

  if (license) {
    notice = `${'/*'}
 * Copyright (C) Sapphirecode - All Rights Reserved
 * This file is part of ${software} which is released under ${license}.
 * See file 'LICENSE' for full license details.
 * Created by Timo Hocker <timo@scode.ovh>, ${month} ${year}
 */

`;
  }
  else {
    notice = `${'/*'}
 * Copyright (C) Sapphirecode - All Rights Reserved
 * Created by Timo Hocker <timo@scode.ovh>, ${month} ${year}
 */

`;
  }
  return notice;
}

/**
 * scans a folder and fixes all copyright notices
 *
 * @param {string} folder folder to scan
 * @param {string} license license name
 * @param {string} software software name
 */
async function fix_all_copy (folder, license = '', software = '') {
  const regex = /\/\*\s+\*\sCopyright[\s\S]*?\*\/\n{0,2}/gu;
  await map_all_files (folder, (data, filename) => {
    const shebang = /^#!.*?\n\n/gu;
    const shebang_line = shebang.exec(data);
    if (!/\.js$/.test(filename) && !regex.test (data))
      return null;
    return (shebang_line ? shebang_line[0] : '') + get_copyright_notice (license, software) + data.replace (regex, '').replace(shebang, '');
  });
}

/**
 * copies the full template to a new folder named after arg[0]
 *
 * @param {string} folder folder to run in
 * @param {Array} args function arguments
 */
function run (folder, args) {
  fix_all_copy (folder, ...args);
}

/**
 * checks if the arguments meet the requirements
 *
 * @param {string} folder folder to run in
 * @param {Array} args function arguments
 * @returns {boolean} true if arguments match requirements
 */
function assert (folder, args) {
  const tests = [
    {
      f:      () => (args.length === 0 || args.length === 2),
      reason: 'invalid number of arguments'
    },
    {
      f:      () => (args.length === 0 || typeof args[0] === 'string'),
      reason: 'license is not a string'
    },
    {
      f:      () => (args.length === 0 || typeof args[1] === 'string'),
      reason: 'software name is not a string'
    },
    {
      f:      () => (typeof folder === 'string'),
      reason: 'cwd is not a folder (internal error)'
    },
    {
      f:      () => (fs.existsSync (folder)),
      reason: 'cwd does not exist (internal error)'
    }
  ];
  for (const test of tests) {
    if (!test.f ()) {
      console.log (test.reason);
      return false;
    }
  }

  return true;
}

module.exports = { run, assert };