chromium/components/subresource_filter/content/browser/subresource_filter_content_settings_manager.h

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_SUBRESOURCE_FILTER_CONTENT_BROWSER_SUBRESOURCE_FILTER_CONTENT_SETTINGS_MANAGER_H_
#define COMPONENTS_SUBRESOURCE_FILTER_CONTENT_BROWSER_SUBRESOURCE_FILTER_CONTENT_SETTINGS_MANAGER_H_

#include <memory>
#include <optional>
#include <utility>

#include "base/memory/raw_ptr.h"
#include "base/time/clock.h"
#include "base/time/time.h"
#include "base/values.h"
#include "components/content_settings/core/common/content_settings.h"

class GURL;
class HostContentSettingsMap;

namespace subresource_filter {

// This class contains helpers to get/set content and website settings related
// to subresource filtering.
//
// Site metadata is stored in two formats as a base::Value::Dict:
// -  V1 (or legacy) metadata, which uses the presence of metadata to indicate
//    activation due to safe browsing and may store additional data for
//    the time since UI was shown, see OnDidShowUI. The absence of metadata
//    indicates no activation.
//    TODO(justinmiron): All V1 metadata will be updated to V2 when it is
//    processed, but we should ideally migrate it all at some point to remove
//    this case.
//
// -  V2 metadata, which explicitly stores the activation status in a key
//    within the metadata dict. This metadata, by default, expires after 1
//    week. However, when metadata is set by an ads intervention, and we
//    and ads interventions are not blocking ads (no activation), the
//    expiration time is explicitly set to match the metadata expiry key in the
//    metadata dict. Additional data may be persisted but will be deleted
//    if there is no activation and the metadata expiry key is not set.
//
// Data stored in the metadata for a url:
// - kInfobarLastShownTimeKey (V1/V2): The last time the info bar was shown for
//   the smart UI.
// - kActivatedKey (V2): The current activation status of the url.
// - kNonRenewingExpiryTime (V2): The time that this url's
//   metadata will expire at and be cleared from the website settings.
//   Note, if this is set, there is no code path that should be able to extend
//   the expiry time. This is a "non-renewable" expiry.
//   TODO(crbug.com/40710549): This ensures that even safe browsing
//   activation is not persisted for the full expiration if it comes after an
//   ads intervention. This is non-ideal and this behavior should be removed
//   when metrics collection is finished, in M88.
//
// TODO(crbug.com/41309958): Once observing changes to content settings is
// robust enough for metrics collection, should collect metrics here too, using
// a content_settings::Observer. Generally speaking, we want a system where we
// can easily log metrics if the content setting has changed meaningfully from
// it's previous value.
class SubresourceFilterContentSettingsManager { … };

}  // namespace subresource_filter

#endif  // COMPONENTS_SUBRESOURCE_FILTER_CONTENT_BROWSER_SUBRESOURCE_FILTER_CONTENT_SETTINGS_MANAGER_H_