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/* -*- 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
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
BinarySearch: "resource://gre/modules/BinarySearch.sys.mjs",
BrowserUtils: "resource://gre/modules/BrowserUtils.sys.mjs",
DeferredTask: "resource://gre/modules/DeferredTask.sys.mjs",
ObjectUtils: "resource://gre/modules/ObjectUtils.sys.mjs",
PlacesUtils: "resource://gre/modules/PlacesUtils.sys.mjs",
});
const BULK_PLACES_EVENTS_THRESHOLD = 50;
const OBSERVER_DEBOUNCE_RATE_MS = 500;
const OBSERVER_DEBOUNCE_TIMEOUT_MS = 5000;
/**
* An object that contains details of a page visit.
*
* @typedef {object} HistoryVisit
*
* @property {Date} date
* When this page was visited.
* @property {string} title
* The page's title.
* @property {string} url
* The page's URL.
*/
/**
* Cache key type depends on how visits are currently being grouped.
*
* By date: number - The start of day timestamp of the visit.
* By site: string - The domain name of the visit.
*
* @typedef {number | string} CacheKey
*/
/**
* Queries the places database using an async read only connection. Maintains
* an internal cache of query results which is live-updated by adding listeners
* to `PlacesObservers`. When the results are no longer needed, call `close` to
* remove the listeners.
*/
export class PlacesQuery {
/** @type {Map<CacheKey, HistoryVisit[]>} */
cachedHistory = null;
/** @type {object} */
cachedHistoryOptions = null;
/** @type {Map<string, Set<HistoryVisit>>} */
#cachedHistoryPerUrl = null;
/** @type {function(PlacesEvent[])} */
#historyListener = null;
/** @type {function(HistoryVisit[])} */
#historyListenerCallback = null;
/** @type {DeferredTask} */
#historyObserverTask = null;
/**
* Indicates whether this query is closed. When closed, caches should not be
* populated, and observers should not be instantiated. It can be reopened by
* calling `initializeCache()`.
*
* @type {boolean}
*/
#isClosed = false;
#searchInProgress = false;
/**
* Get a snapshot of history visits at this moment.
*
* @param {object} [options]
* Options to apply to the database query.
* @param {number} [options.daysOld]
* The maximum number of days to go back in history.
* @param {number} [options.limit]
* The maximum number of visits to return.
* @param {string} [options.sortBy]
* The sorting order of history visits:
* - "date": Group visits based on the date they occur.
* - "site": Group visits based on host, excluding any "www." prefix.
* @returns {Map<any, HistoryVisit[]>}
* History visits obtained from the database query.
*/
async getHistory({ daysOld = 60, limit, sortBy = "date" } = {}) {
const options = { daysOld, limit, sortBy };
const cacheInvalid =
this.cachedHistory == null ||
!lazy.ObjectUtils.deepEqual(options, this.cachedHistoryOptions);
if (cacheInvalid) {
this.initializeCache(options);
await this.fetchHistory();
}
if (!this.#historyListener && !this.#isClosed) {
this.#initHistoryListener();
}
return this.cachedHistory;
}
/**
* Clear existing cache and store options for the new query.
*
* @param {object} options
* The database query options.
*/
initializeCache(options = this.cachedHistoryOptions) {
this.cachedHistory = new Map();
this.cachedHistoryOptions = options;
this.#cachedHistoryPerUrl = new Map();
this.#isClosed = false;
}
/**
* Run the database query and populate the history cache.
*/
async fetchHistory() {
const { daysOld, limit, sortBy } = this.cachedHistoryOptions;
const db = await lazy.PlacesUtils.promiseDBConnection();
let groupBy;
switch (sortBy) {
case "date":
groupBy = "url, date(visit_date / 1000000, 'unixepoch', 'localtime')";
break;
case "site":
groupBy = "url";
break;
}
const whereClause =
daysOld == Infinity
? ""
: `WHERE visit_date >= (strftime('%s','now','localtime','start of day','-${Number(
daysOld
)} days','utc') * 1000000)`;
const sql = `SELECT MAX(visit_date) as visit_date, title, url
FROM moz_historyvisits v
JOIN moz_places h
ON v.place_id = h.id
AND hidden = 0
${whereClause}
GROUP BY ${groupBy}
ORDER BY visit_date DESC
LIMIT ${limit > 0 ? limit : -1}`;
const rows = await db.executeCached(sql);
if (this.#isClosed) {
// Do not cache visits if this instance is closed already.
return;
}
for (const row of rows) {
const visit = this.formatRowAsVisit(row);
this.#appendToCache(visit);
}
}
/**
* Search the database for visits matching a search query. This does not
* affect internal caches, and observers will not be notified of search
* results obtained from this query.
*
* @param {string} query
* The search query.
* @param {number} [limit]
* The maximum number of visits to return.
* @returns {HistoryVisit[]}
* The matching visits.
*/
async searchHistory(query, limit) {
const { sortBy } = this.cachedHistoryOptions;
const db = await lazy.PlacesUtils.promiseLargeCacheDBConnection();
let orderBy;
switch (sortBy) {
case "date":
orderBy = "visit_date DESC";
break;
case "site":
orderBy = "url";
break;
}
const sql = `SELECT MAX(visit_date) as visit_date, title, url
FROM moz_historyvisits v
JOIN moz_places h
ON v.place_id = h.id
WHERE AUTOCOMPLETE_MATCH(:query, url, title, NULL, 1, 1, 1, 1, :matchBehavior, :searchBehavior, NULL)
AND hidden = 0
GROUP BY url
ORDER BY ${orderBy}
LIMIT ${limit > 0 ? limit : -1}`;
if (this.#searchInProgress) {
db.interrupt();
}
try {
this.#searchInProgress = true;
const rows = await db.executeCached(sql, {
query,
matchBehavior: Ci.mozIPlacesAutoComplete.MATCH_ANYWHERE_UNMODIFIED,
searchBehavior: Ci.mozIPlacesAutoComplete.BEHAVIOR_HISTORY,
});
return rows.map(row => this.formatRowAsVisit(row));
} finally {
this.#searchInProgress = false;
}
}
/**
* Append a visit into the container it belongs to.
*
* @param {HistoryVisit} visit
* The visit to append.
*/
#appendToCache(visit) {
this.#getContainerForVisit(visit).push(visit);
this.#insertIntoCachedHistoryPerUrl(visit);
}
/**
* Insert a visit into the container it belongs to, ensuring to maintain
* sorted order. Used for handling `page-visited` events after the initial
* fetch of history data.
*
* @param {HistoryVisit} visit
* The visit to insert.
*/
#insertSortedIntoCache(visit) {
const container = this.#getContainerForVisit(visit);
const existingVisitsForUrl = this.#cachedHistoryPerUrl.get(visit.url) ?? [];
for (const existingVisit of existingVisitsForUrl) {
if (this.#getContainerForVisit(existingVisit) === container) {
if (existingVisit.date.getTime() >= visit.date.getTime()) {
// Existing visit is more recent. Don't insert this one.
return;
}
// Remove the existing visit, then insert the new one.
container.splice(container.indexOf(existingVisit), 1);
existingVisitsForUrl.delete(existingVisit);
break;
}
}
let insertionPoint = 0;
if (visit.date.getTime() < container[0]?.date.getTime()) {
insertionPoint = lazy.BinarySearch.insertionIndexOf(
(a, b) => b.date.getTime() - a.date.getTime(),
container,
visit
);
}
container.splice(insertionPoint, 0, visit);
this.#insertIntoCachedHistoryPerUrl(visit);
}
/**
* Insert a visit into the url-keyed history cache.
*
* @param {HistoryVisit} visit
* The visit to insert.
*/
#insertIntoCachedHistoryPerUrl(visit) {
const container = this.#cachedHistoryPerUrl.get(visit.url);
if (container) {
container.add(visit);
} else {
this.#cachedHistoryPerUrl.set(visit.url, new Set().add(visit));
}
}
/**
* Retrieve the corresponding container for this visit.
*
* @param {HistoryVisit} visit
* The visit to check.
* @returns {HistoryVisit[]}
* The container it belongs to.
*/
#getContainerForVisit(visit) {
const mapKey = this.#getMapKeyForVisit(visit);
let container = this.cachedHistory?.get(mapKey);
if (!container) {
container = [];
this.cachedHistory?.set(mapKey, container);
}
return container;
}
#getMapKeyForVisit(visit) {
switch (this.cachedHistoryOptions.sortBy) {
case "date":
return this.getStartOfDayTimestamp(visit.date);
case "site": {
const { protocol } = new URL(visit.url);
return protocol === "http:" || protocol === "https:"
? lazy.BrowserUtils.formatURIStringForDisplay(visit.url)
: "";
}
}
return null;
}
/**
* Observe changes to the visits table. When changes are made, the callback
* is given the new list of visits. Only one callback can be active at a time
* (per instance). If one already exists, it will be replaced.
*
* @param {function(HistoryVisit[])} callback
* The function to call when changes are made.
*/
observeHistory(callback) {
this.#historyListenerCallback = callback;
}
/**
* Close this query. Caches are cleared and listeners are removed.
*/
close() {
this.#isClosed = true;
this.cachedHistory = null;
this.cachedHistoryOptions = null;
this.#cachedHistoryPerUrl = null;
if (this.#historyListener) {
PlacesObservers.removeListener(
[
"page-removed",
"page-visited",
"history-cleared",
"page-title-changed",
],
this.#historyListener
);
}
this.#historyListener = null;
this.#historyListenerCallback = null;
if (this.#historyObserverTask && !this.#historyObserverTask.isFinalized) {
this.#historyObserverTask.disarm();
this.#historyObserverTask.finalize();
}
}
/**
* Listen for changes to the visits table and update caches accordingly.
*/
#initHistoryListener() {
this.#historyObserverTask = new lazy.DeferredTask(
async () => {
if (typeof this.#historyListenerCallback === "function") {
const history = await this.getHistory(this.cachedHistoryOptions);
this.#historyListenerCallback(history);
}
},
OBSERVER_DEBOUNCE_RATE_MS,
OBSERVER_DEBOUNCE_TIMEOUT_MS
);
this.#historyListener = async events => {
if (
events.length >= BULK_PLACES_EVENTS_THRESHOLD ||
events.some(({ type }) => type === "page-removed")
) {
// Accounting for cascading deletes, or handling places events in bulk,
// can be expensive. In this case, we invalidate the cache once rather
// than handling each event individually.
this.cachedHistory = null;
} else if (this.cachedHistory != null) {
for (const event of events) {
switch (event.type) {
case "page-visited":
this.handlePageVisited(event);
break;
case "history-cleared":
this.initializeCache();
break;
case "page-title-changed":
this.handlePageTitleChanged(event);
break;
}
}
}
this.#historyObserverTask.arm();
};
PlacesObservers.addListener(
["page-removed", "page-visited", "history-cleared", "page-title-changed"],
this.#historyListener
);
}
/**
* Handle a page visited event.
*
* @param {PlacesEvent} event
* The event.
* @return {HistoryVisit}
* The visit that was inserted, or `null` if no visit was inserted.
*/
handlePageVisited(event) {
if (event.hidden) {
return null;
}
const visit = this.formatEventAsVisit(event);
this.#insertSortedIntoCache(visit);
return visit;
}
/**
* Handle a page title changed event.
*
* @param {PlacesEvent} event
* The event.
*/
handlePageTitleChanged(event) {
const visits = this.#cachedHistoryPerUrl.get(event.url);
if (visits == null) {
return;
}
for (const visit of visits) {
visit.title = event.title;
}
}
/**
* Get timestamp from a date by only considering its year, month, and date
* (so that it can be used as a date-based key).
*
* @param {Date} date
* The date to truncate.
* @returns {number}
* The corresponding timestamp.
*/
getStartOfDayTimestamp(date) {
return new Date(
date.getFullYear(),
date.getMonth(),
date.getDate()
).getTime();
}
/**
* Get timestamp from a date by only considering its year and month (so that
* it can be used as a month-based key).
*
* @param {Date} date
* The date to truncate.
* @returns {number}
* The corresponding timestamp.
*/
getStartOfMonthTimestamp(date) {
return new Date(date.getFullYear(), date.getMonth()).getTime();
}
/**
* Format a database row as a history visit.
*
* @param {mozIStorageRow} row
* The row to format.
* @returns {HistoryVisit}
* The resulting history visit.
*/
formatRowAsVisit(row) {
return {
date: lazy.PlacesUtils.toDate(row.getResultByName("visit_date")),
title: row.getResultByName("title"),
url: row.getResultByName("url"),
};
}
/**
* Format a page visited event as a history visit.
*
* @param {PlacesEvent} event
* The event to format.
* @returns {HistoryVisit}
* The resulting history visit.
*/
formatEventAsVisit(event) {
return {
date: new Date(event.visitTime),
title: event.lastKnownTitle,
url: event.url,
};
}
}