toolkit/components/places/TaggingService.jsm
author Nika Layzell <nika@thelayzells.com>
Thu, 06 Aug 2020 14:04:13 +0000
changeset 544125 ee09cb88af177571304759bc05c760e3d82fd1ed
parent 540012 8cf125948dc084e8e9131120f8356f488f3ed774
permissions -rw-r--r--
Bug 1656854 - Part 2: Add a BrowsingContextGroup keepalive to BrowserParent shutdown, r=farre In bug 1652085, I added BrowsingContextGroup keepalives while waiting for replies to the discard message, however that message isn't actually sent to the current owner process. Instead, the BrowsingContext is discarded by the PBrowser being destroyed. This should help ensure we also keep the group alive during normal BrowserParent destruction. Differential Revision: https://phabricator.services.mozilla.com/D85897

/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

const { ComponentUtils } = ChromeUtils.import(
  "resource://gre/modules/ComponentUtils.jsm"
);
const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
const { PlacesUtils } = ChromeUtils.import(
  "resource://gre/modules/PlacesUtils.jsm"
);

const TOPIC_SHUTDOWN = "places-shutdown";

/**
 * The Places Tagging Service
 */
function TaggingService() {
  this.handlePlacesEvents = this.handlePlacesEvents.bind(this);

  // Observe bookmarks changes.
  PlacesUtils.bookmarks.addObserver(this);
  PlacesUtils.observers.addListener(
    ["bookmark-added", "bookmark-removed"],
    this.handlePlacesEvents
  );

  // Cleanup on shutdown.
  Services.obs.addObserver(this, TOPIC_SHUTDOWN);
}

TaggingService.prototype = {
  /**
   * Creates a tag container under the tags-root with the given name.
   *
   * @param aTagName
   *        the name for the new tag.
   * @param aSource
   *        a change source constant from nsINavBookmarksService::SOURCE_*.
   * @returns the id of the new tag container.
   */
  _createTag: function TS__createTag(aTagName, aSource) {
    var newFolderId = PlacesUtils.bookmarks.createFolder(
      PlacesUtils.tagsFolderId,
      aTagName,
      PlacesUtils.bookmarks.DEFAULT_INDEX,
      /* aGuid */ null,
      aSource
    );
    // Add the folder to our local cache, so we can avoid doing this in the
    // observer that would have to check itemType.
    this._tagFolders[newFolderId] = aTagName;

    return newFolderId;
  },

  /**
   * Checks whether the given uri is tagged with the given tag.
   *
   * @param [in] aURI
   *        url to check for
   * @param [in] aTagName
   *        the tag to check for
   * @returns the item id if the URI is tagged with the given tag, -1
   *          otherwise.
   */
  _getItemIdForTaggedURI: function TS__getItemIdForTaggedURI(aURI, aTagName) {
    var tagId = this._getItemIdForTag(aTagName);
    if (tagId == -1) {
      return -1;
    }
    // Using bookmarks service API for this would be a pain.
    // Until tags implementation becomes sane, go the query way.
    let db = PlacesUtils.history.DBConnection;
    let stmt = db.createStatement(
      `SELECT id FROM moz_bookmarks
       WHERE parent = :tag_id
       AND fk = (SELECT id FROM moz_places WHERE url_hash = hash(:page_url) AND url = :page_url)`
    );
    stmt.params.tag_id = tagId;
    stmt.params.page_url = aURI.spec;
    try {
      if (stmt.executeStep()) {
        return stmt.row.id;
      }
    } finally {
      stmt.finalize();
    }
    return -1;
  },

  /**
   * Returns the folder id for a tag, or -1 if not found.
   * @param [in] aTag
   *        string tag to search for
   * @returns integer id for the bookmark folder for the tag
   */
  _getItemIdForTag: function TS_getItemIdForTag(aTagName) {
    for (var i in this._tagFolders) {
      if (aTagName.toLowerCase() == this._tagFolders[i].toLowerCase()) {
        return parseInt(i);
      }
    }
    return -1;
  },
  /**
   * Makes a proper array of tag objects like  { id: number, name: string }.
   *
   * @param aTags
   *        Array of tags.  Entries can be tag names or concrete item id.
   * @param trim [optional]
   *        Whether to trim passed-in named tags. Defaults to false.
   * @return Array of tag objects like { id: number, name: string }.
   *
   * @throws Cr.NS_ERROR_INVALID_ARG if any element of the input array is not
   *         a valid tag.
   */
  _convertInputMixedTagsArray(aTags, trim = false) {
    // Handle sparse array with a .filter.
    return aTags
      .filter(tag => tag !== undefined)
      .map(idOrName => {
        let tag = {};
        if (typeof idOrName == "number" && this._tagFolders[idOrName]) {
          // This is a tag folder id.
          tag.id = idOrName;
          // We can't know the name at this point, since a previous tag could
          // want to change it.
          tag.__defineGetter__("name", () => this._tagFolders[tag.id]);
        } else if (
          typeof idOrName == "string" &&
          !!idOrName.length &&
          idOrName.length <= PlacesUtils.bookmarks.MAX_TAG_LENGTH
        ) {
          // This is a tag name.
          tag.name = trim ? idOrName.trim() : idOrName;
          // We can't know the id at this point, since a previous tag could
          // have created it.
          tag.__defineGetter__("id", () => this._getItemIdForTag(tag.name));
        } else {
          throw Components.Exception(
            "Invalid tag value",
            Cr.NS_ERROR_INVALID_ARG
          );
        }
        return tag;
      });
  },

  // nsITaggingService
  tagURI: function TS_tagURI(aURI, aTags, aSource) {
    if (!aURI || !aTags || !Array.isArray(aTags) || !aTags.length) {
      throw Components.Exception(
        "Invalid value for tags",
        Cr.NS_ERROR_INVALID_ARG
      );
    }

    // This also does some input validation.
    let tags = this._convertInputMixedTagsArray(aTags, true);

    for (let tag of tags) {
      if (tag.id == -1) {
        // Tag does not exist yet, create it.
        this._createTag(tag.name, aSource);
      }

      let itemId = this._getItemIdForTaggedURI(aURI, tag.name);
      if (itemId == -1) {
        // The provided URI is not yet tagged, add a tag for it.
        // Note that bookmarks under tag containers must have null titles.
        PlacesUtils.bookmarks.insertBookmark(
          tag.id,
          aURI,
          PlacesUtils.bookmarks.DEFAULT_INDEX,
          /* aTitle */ null,
          /* aGuid */ null,
          aSource
        );
      } else {
        // Otherwise, bump the tag's timestamp, so that we can increment the
        // sync change counter for all bookmarks with the URI.
        PlacesUtils.bookmarks.setItemLastModified(
          itemId,
          PlacesUtils.toPRTime(Date.now()),
          aSource
        );
      }

      // Try to preserve user's tag name casing.
      // Rename the tag container so the Places view matches the most-recent
      // user-typed value.
      if (PlacesUtils.bookmarks.getItemTitle(tag.id) != tag.name) {
        // this._tagFolders is updated by the bookmarks observer.
        PlacesUtils.bookmarks.setItemTitle(tag.id, tag.name, aSource);
      }
    }
  },

  /**
   * Removes the tag container from the tags root if the given tag is empty.
   *
   * @param aTagId
   *        the itemId of the tag element under the tags root
   * @param aSource
   *        a change source constant from nsINavBookmarksService::SOURCE_*
   */
  _removeTagIfEmpty: function TS__removeTagIfEmpty(aTagId, aSource) {
    let count = 0;
    let db = PlacesUtils.history.DBConnection;
    let stmt = db.createStatement(
      `SELECT count(*) AS count FROM moz_bookmarks
       WHERE parent = :tag_id`
    );
    stmt.params.tag_id = aTagId;
    try {
      if (stmt.executeStep()) {
        count = stmt.row.count;
      }
    } finally {
      stmt.finalize();
    }

    if (count == 0) {
      PlacesUtils.bookmarks.removeItem(aTagId, aSource);
    }
  },

  // nsITaggingService
  untagURI: function TS_untagURI(aURI, aTags, aSource) {
    if (!aURI || (aTags && (!Array.isArray(aTags) || !aTags.length))) {
      throw Components.Exception(
        "Invalid value for tags",
        Cr.NS_ERROR_INVALID_ARG
      );
    }

    if (!aTags) {
      // Passing null should clear all tags for aURI, see the IDL.
      // XXXmano: write a perf-sensitive version of this code path...
      aTags = this.getTagsForURI(aURI);
    }

    // This also does some input validation.
    let tags = this._convertInputMixedTagsArray(aTags);

    let isAnyTagNotTrimmed = tags.some(tag => /^\s|\s$/.test(tag.name));
    if (isAnyTagNotTrimmed) {
      throw Components.Exception(
        "At least one tag passed to untagURI was not trimmed",
        Cr.NS_ERROR_INVALID_ARG
      );
    }

    for (let tag of tags) {
      if (tag.id != -1) {
        // A tag could exist.
        let itemId = this._getItemIdForTaggedURI(aURI, tag.name);
        if (itemId != -1) {
          // There is a tagged item.
          PlacesUtils.bookmarks.removeItem(itemId, aSource);
        }
      }
    }
  },

  // nsITaggingService
  getTagsForURI: function TS_getTagsForURI(aURI) {
    if (!aURI) {
      throw Components.Exception("Invalid uri", Cr.NS_ERROR_INVALID_ARG);
    }

    let tags = [];
    let db = PlacesUtils.history.DBConnection;
    let stmt = db.createStatement(
      `SELECT t.id AS folderId
       FROM moz_bookmarks b
       JOIN moz_bookmarks t on t.id = b.parent
       WHERE b.fk = (SELECT id FROM moz_places WHERE url_hash = hash(:url) AND url = :url) AND
       t.parent = :tags_root
       ORDER BY b.lastModified DESC, b.id DESC`
    );
    stmt.params.url = aURI.spec;
    stmt.params.tags_root = PlacesUtils.tagsFolderId;
    try {
      while (stmt.executeStep()) {
        try {
          tags.push(this._tagFolders[stmt.row.folderId]);
        } catch (ex) {}
      }
    } finally {
      stmt.finalize();
    }

    // sort the tag list
    tags.sort(function(a, b) {
      return a.toLowerCase().localeCompare(b.toLowerCase());
    });
    return tags;
  },

  __tagFolders: null,
  get _tagFolders() {
    if (!this.__tagFolders) {
      this.__tagFolders = [];

      let db = PlacesUtils.history.DBConnection;
      let stmt = db.createStatement(
        "SELECT id, title FROM moz_bookmarks WHERE parent = :tags_root "
      );
      stmt.params.tags_root = PlacesUtils.tagsFolderId;
      try {
        while (stmt.executeStep()) {
          this.__tagFolders[stmt.row.id] = stmt.row.title;
        }
      } finally {
        stmt.finalize();
      }
    }

    return this.__tagFolders;
  },

  // nsIObserver
  observe: function TS_observe(aSubject, aTopic, aData) {
    if (aTopic == TOPIC_SHUTDOWN) {
      PlacesUtils.bookmarks.removeObserver(this);
      PlacesUtils.observers.removeListener(
        ["bookmark-added", "bookmark-removed"],
        this.handlePlacesEvents
      );
      Services.obs.removeObserver(this, TOPIC_SHUTDOWN);
    }
  },

  /**
   * If the only bookmark items associated with aURI are contained in tag
   * folders, returns the IDs of those items.  This can be the case if
   * the URI was bookmarked and tagged at some point, but the bookmark was
   * removed, leaving only the bookmark items in tag folders.  If the URI is
   * either properly bookmarked or not tagged just returns and empty array.
   *
   * @param   aURI
   *          A URI (string) that may or may not be bookmarked
   * @returns an array of item ids
   */
  _getTaggedItemIdsIfUnbookmarkedURI: function TS__getTaggedItemIdsIfUnbookmarkedURI(
    url
  ) {
    var itemIds = [];
    var isBookmarked = false;

    // Using bookmarks service API for this would be a pain.
    // Until tags implementation becomes sane, go the query way.
    let db = PlacesUtils.history.DBConnection;
    let stmt = db.createStatement(
      `SELECT id, parent
       FROM moz_bookmarks
       WHERE fk = (SELECT id FROM moz_places WHERE url_hash = hash(:page_url) AND url = :page_url)`
    );
    stmt.params.page_url = url;
    try {
      while (stmt.executeStep() && !isBookmarked) {
        if (this._tagFolders[stmt.row.parent]) {
          // This is a tag entry.
          itemIds.push(stmt.row.id);
        } else {
          // This is a real bookmark, so the bookmarked URI is not an orphan.
          isBookmarked = true;
        }
      }
    } finally {
      stmt.finalize();
    }

    return isBookmarked ? [] : itemIds;
  },

  handlePlacesEvents(events) {
    for (let event of events) {
      switch (event.type) {
        case "bookmark-added":
          if (
            !event.isTagging ||
            event.itemType != PlacesUtils.bookmarks.TYPE_FOLDER
          ) {
            continue;
          }

          this._tagFolders[event.id] = event.title;
          break;
        case "bookmark-removed":
          // Item is a tag folder.
          if (
            event.parentId == PlacesUtils.tagsFolderId &&
            this._tagFolders[event.id]
          ) {
            delete this._tagFolders[event.id];
            break;
          }

          Services.tm.dispatchToMainThread(() => {
            if (event.url && !this._tagFolders[event.parentId]) {
              // Item is a bookmark that was removed from a non-tag folder.
              // If the only bookmark items now associated with the bookmark's URI are
              // contained in tag folders, the URI is no longer properly bookmarked, so
              // untag it.
              let itemIds = this._getTaggedItemIdsIfUnbookmarkedURI(event.url);
              for (let i = 0; i < itemIds.length; i++) {
                try {
                  PlacesUtils.bookmarks.removeItem(itemIds[i], event.source);
                } catch (ex) {}
              }
            } else if (event.url && this._tagFolders[event.parentId]) {
              // Item is a tag entry.  If this was the last entry for this tag, remove it.
              this._removeTagIfEmpty(event.parentId, event.source);
            }
          });
          break;
      }
    }
  },

  onItemChanged: function TS_onItemChanged(
    aItemId,
    aProperty,
    aIsAnnotationProperty,
    aNewValue,
    aLastModified,
    aItemType
  ) {
    if (aProperty == "title" && this._tagFolders[aItemId]) {
      this._tagFolders[aItemId] = aNewValue;
    }
  },

  onItemMoved: function TS_onItemMoved(
    aItemId,
    aOldParent,
    aOldIndex,
    aNewParent,
    aNewIndex,
    aItemType
  ) {
    if (
      this._tagFolders[aItemId] &&
      PlacesUtils.tagsFolderId == aOldParent &&
      PlacesUtils.tagsFolderId != aNewParent
    ) {
      delete this._tagFolders[aItemId];
    }
  },

  onItemVisited() {},
  onBeginUpdateBatch() {},
  onEndUpdateBatch() {},

  // nsISupports

  classID: Components.ID("{bbc23860-2553-479d-8b78-94d9038334f7}"),

  _xpcom_factory: ComponentUtils.generateSingletonFactory(TaggingService),

  QueryInterface: ChromeUtils.generateQI([
    "nsITaggingService",
    "nsINavBookmarkObserver",
    "nsIObserver",
  ]),
};

/**
 * Class tracking a single tag autocomplete search.
 */
class TagSearch {
  constructor(searchString, autocompleteSearch, listener) {
    // We need a result regardless of having matches.
    this._result = Cc[
      "@mozilla.org/autocomplete/simple-result;1"
    ].createInstance(Ci.nsIAutoCompleteSimpleResult);
    this._result.setDefaultIndex(0);
    this._result.setSearchString(searchString);

    this._autocompleteSearch = autocompleteSearch;
    this._listener = listener;
  }

  async start() {
    if (this._canceled) {
      throw new Error("Can't restart a canceled search");
    }

    let searchString = this._result.searchString;
    // Only search on characters for the last tag.
    let index = Math.max(
      searchString.lastIndexOf(","),
      searchString.lastIndexOf(";")
    );
    let before = "";
    if (index != -1) {
      before = searchString.slice(0, index + 1);
      searchString = searchString.slice(index + 1);
      // skip past whitespace
      var m = searchString.match(/\s+/);
      if (m) {
        before += m[0];
        searchString = searchString.slice(m[0].length);
      }
    }

    if (searchString.length) {
      let tags = await PlacesUtils.bookmarks.fetchTags();
      if (this._canceled) {
        return;
      }

      let lcSearchString = searchString.toLowerCase();
      let matchingTags = tags
        .filter(t => t.name.toLowerCase().startsWith(lcSearchString))
        .map(t => t.name);

      for (let i = 0; i < matchingTags.length; ++i) {
        let tag = matchingTags[i];
        // For each match, prepend what the user has typed so far.
        this._result.appendMatch(before + tag, tag);
        // In case of many tags, notify once every 10.
        if (i % 10 == 0) {
          this._notifyResult(true);
          // yield to avoid monopolizing the main-thread
          await new Promise(resolve =>
            Services.tm.dispatchToMainThread(resolve)
          );
          if (this._canceled) {
            return;
          }
        }
      }
    }

    // Search is done.
    this._notifyResult(false);
  }

  cancel() {
    this._canceled = true;
  }

  _notifyResult(searchOngoing) {
    let resultCode = this._result.matchCount
      ? "RESULT_SUCCESS"
      : "RESULT_NOMATCH";
    if (searchOngoing) {
      resultCode += "_ONGOING";
    }
    this._result.setSearchResult(Ci.nsIAutoCompleteResult[resultCode]);
    this._listener.onSearchResult(this._autocompleteSearch, this._result);
  }
}

// Implements nsIAutoCompleteSearch
function TagAutoCompleteSearch() {}

TagAutoCompleteSearch.prototype = {
  /*
   * Search for a given string and notify a listener of the result.
   *
   * @param searchString - The string to search for
   * @param searchParam - An extra parameter
   * @param previousResult - A previous result to use for faster searching
   * @param listener - A listener to notify when the search is complete
   */
  startSearch(searchString, searchParam, previousResult, listener) {
    if (this._search) {
      this._search.cancel();
    }
    this._search = new TagSearch(searchString, this, listener);
    this._search.start().catch(Cu.reportError);
  },

  /**
   * Stop an asynchronous search that is in progress
   */
  stopSearch() {
    this._search.cancel();
    this._search = null;
  },

  classID: Components.ID("{1dcc23b0-d4cb-11dc-9ad6-479d56d89593}"),
  QueryInterface: ChromeUtils.generateQI(["nsIAutoCompleteSearch"]),
};

var EXPORTED_SYMBOLS = ["TaggingService", "TagAutoCompleteSearch"];