'use strict';

let fs = require('fs');
let Path = require('path');
let logger = require('./logger');

module.exports = find_config_file;

function find_config_file() {
  let paths = get_paths();

  for (let i=0; i<paths.length; i++) {
    if (file_exists(paths[i].path)) return paths[i].path;
  }

  create_config_file(paths[0]);
  return paths[0].path;
}

function create_config_file(config_path) {
  require('mkdirp').sync(Path.dirname(config_path.path));
  logger.logger.info({file: config_path.path}, 'Creating default config file in @{file}');

  let created_config = fs.readFileSync(require.resolve('../conf/default.yaml'), 'utf8');

  if (config_path.type === 'xdg') {
    let data_dir = process.env.XDG_DATA_HOME
                || Path.join(process.env.HOME, '.local', 'share');
    if (folder_exists(data_dir)) {
      data_dir = Path.resolve(Path.join(data_dir, 'verdaccio', 'storage'));
      created_config = created_config.replace(/^storage: .\/storage$/m, 'storage: ' + data_dir);
    }
  }

  fs.writeFileSync(config_path.path, created_config);
}

function get_paths() {
  let try_paths = [];
  let xdg_config = process.env.XDG_CONFIG_HOME
                || process.env.HOME && Path.join(process.env.HOME, '.config');
  if (xdg_config && folder_exists(xdg_config)) {
    try_paths.push({
      path: Path.join(xdg_config, 'verdaccio', 'config.yaml'),
      type: 'xdg',
    });
  }

  if (process.platform === 'win32'
   && process.env.APPDATA
   && folder_exists(process.env.APPDATA)) {
    try_paths.push({
      path: Path.resolve(Path.join(process.env.APPDATA, 'verdaccio', 'config.yaml')),
      type: 'win',
    });
  }

  try_paths.push({
    path: Path.resolve(Path.join('.', 'verdaccio', 'config.yaml')),
    type: 'def',
  });

  // backward compatibility
  try_paths.push({
    path: Path.resolve(Path.join('.', 'config.yaml')),
    type: 'old',
  });

  return try_paths;
}

function folder_exists(path) {
  try {
    var stat = fs.statSync(path);
  } catch(_) {
    return false;
  }

  return stat.isDirectory();
}

function file_exists(path) {
  try {
    var stat = fs.statSync(path);
  } catch(_) {
    return false;
  }

  return stat.isFile();
}