/**
* GNU LibreJS - A browser add-on to block nonfree nontrivial JavaScript.
*
* Copyright (C) 2018 Giorgio Maone <giorgio@maone.net>
* Copyright (C) 2022 Yuchen Pei <id@ypei.org>
*
* This file is part of GNU LibreJS.
*
* GNU LibreJS is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GNU LibreJS is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU LibreJS.  If not, see <http://www.gnu.org/licenses/>.
*/

/*
  A class to manage whitelist/blacklist operations
*/

const { ListStore } = require('../common/Storage');

class ListManager {
  constructor(whitelist, blacklist, builtInHashes) {
    this.lists = { whitelist, blacklist };
    this.builtInHashes = new Set(builtInHashes);
  }

  static async move(fromList, toList, ...keys) {
    await Promise.all([fromList.remove(...keys), toList.store(...keys)]);
  }

  async whitelist(...keys) {
    await ListManager.move(this.lists.blacklist, this.lists.whitelist, ...keys);
  }
  async blacklist(...keys) {
    await ListManager.move(this.lists.whitelist, this.lists.blacklist, ...keys);
  }
  async forget(...keys) {
    await Promise.all(Object.values(this.lists).map(async l => await l.remove(...keys)));
  }
  /* key is a string representing either a URL or an optional path
    with a trailing (hash).
    Returns "blacklisted", "whitelisted" or defValue
  */
  getStatus(key, defValue = 'unknown') {
    const { blacklist, whitelist } = this.lists;
    const inline = ListStore.inlineItem(key);
    if (inline) {
      return blacklist.contains(inline)
        ? 'blacklisted'
        : whitelist.contains(inline) ? 'whitelisted'
          : defValue;
    }

    const match = key.match(/\(([^)]+)\)(?=[^()]*$)/);
    if (!match) {
      const url = ListStore.urlItem(key);
      const site = ListStore.siteItem(key);
      return (blacklist.contains(url) || ListManager.siteMatch(site, blacklist)
        ? 'blacklisted'
        : whitelist.contains(url) || ListManager.siteMatch(site, whitelist)
          ? 'whitelisted' : defValue
      );
    }

    const [hashItem, srcHash] = match; // (hash), hash
    return blacklist.contains(hashItem) ? 'blacklisted'
      : this.builtInHashes.has(srcHash) || whitelist.contains(hashItem)
        ? 'whitelisted'
        : defValue;
  }

  /*
    Matches by whole site ("http://some.domain.com/*") supporting also
    wildcarded subdomains ("https://*.domain.com/*").
  */
  static siteMatch(url, list) {
    const site = ListStore.siteItem(url);
    if (list.contains(site)) return site;
    // TODO: get rid of let
    for (let replaced = site.replace(/^([\w-]+:\/\/)?(\w)/, '$1*.$2'); ;) {
      if (list.contains(replaced)) return replaced;
      const oldKey = replaced;
      replaced = replaced.replace(/(?:\*\.)*\w+(?=\.)/, '*');
      if (oldKey === replaced) return null;
    }
  }
}

module.exports = { ListManager };