// 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_BLOCKED_CONTENT_SAFE_BROWSING_TRIGGERED_POPUP_BLOCKER_H_
#define COMPONENTS_BLOCKED_CONTENT_SAFE_BROWSING_TRIGGERED_POPUP_BLOCKER_H_

#include <optional>

#include "base/feature_list.h"
#include "base/gtest_prod_util.h"
#include "base/scoped_observation.h"
#include "components/safe_browsing/core/browser/db/util.h"
#include "components/subresource_filter/content/browser/subresource_filter_observer.h"
#include "components/subresource_filter/content/browser/subresource_filter_observer_manager.h"
#include "content/public/browser/navigation_handle_user_data.h"
#include "content/public/browser/page_user_data.h"
#include "content/public/browser/web_contents_observer.h"

namespace content {
class WebContents;
}  // namespace content

namespace user_prefs {
class PrefRegistrySyncable;
}

namespace blocked_content {
BASE_DECLARE_FEATURE(kAbusiveExperienceEnforce);

constexpr char kAbusiveEnforceMessage[] =
    "Chrome prevented this site from opening a new tab or window. Learn more "
    "at https://www.chromestatus.com/feature/5243055179300864";
constexpr char kAbusiveWarnMessage[] =
    "Chrome might start preventing this site from opening new tabs or "
    "windows in the future. Learn more at "
    "https://www.chromestatus.com/feature/5243055179300864";

// This class observes main frame navigation checks incoming from safe browsing
// (currently implemented by the subresource_filter component). For navigations
// which match the ABUSIVE safe browsing list, this class will help the popup
// tab helper in applying a stronger policy for blocked popups.
class SafeBrowsingTriggeredPopupBlocker
    : public content::WebContentsObserver,
      public content::WebContentsUserData<SafeBrowsingTriggeredPopupBlocker>,
      public subresource_filter::SubresourceFilterObserver {
 public:
  // This enum backs a histogram. Please append new entries to the end, and
  // update enums.xml when making changes.
  enum class Action : int {
    // User committed a navigation to a non-error page.
    kNavigation,

    // Safe Browsing considered this page abusive and the page should be warned.
    // Logged at navigation commit.
    kWarningSite,

    // Safe Browsing considered this page abusive and the page should be be
    // blocked against. Logged at navigation commit.
    kEnforcedSite,

    // The popup blocker called into this object to ask if the strong blocking
    // should be applied.
    kConsidered,

    // This object responded to the popup blocker in the affirmative, and the
    // popup was blocked.
    kBlocked,

    // Add new entries before this one
    kCount
  };

  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);

  // Creates a SafeBrowsingTriggeredPopupBlocker and attaches it (via UserData)
  // to |web_contents|.
  static void MaybeCreate(content::WebContents* web_contents);

  SafeBrowsingTriggeredPopupBlocker(const SafeBrowsingTriggeredPopupBlocker&) =
      delete;
  SafeBrowsingTriggeredPopupBlocker& operator=(
      const SafeBrowsingTriggeredPopupBlocker&) = delete;

  ~SafeBrowsingTriggeredPopupBlocker() override;

  bool ShouldApplyAbusivePopupBlocker(content::Page& page);

 private:
  FRIEND_TEST_ALL_PREFIXES(SafeBrowsingTriggeredPopupBlockerTest,
                           NonPrimaryFrameTree);
  friend class content::WebContentsUserData<SafeBrowsingTriggeredPopupBlocker>;
  // The |web_contents| and |observer_manager| are expected to be
  // non-nullptr.
  SafeBrowsingTriggeredPopupBlocker(
      content::WebContents* web_contents,
      subresource_filter::SubresourceFilterObserverManager* observer_manager);

  // content::WebContentsObserver:
  void DidFinishNavigation(
      content::NavigationHandle* navigation_handle) override;

  // subresource_filter::SubresourceFilterObserver:
  void OnSafeBrowsingChecksComplete(
      content::NavigationHandle* navigation_handle,
      const subresource_filter::SubresourceFilterSafeBrowsingClient::
          CheckResult& result) override;
  void OnSubresourceFilterGoingAway() override;

  // Enabled state is governed by both a feature flag and a pref (which can be
  // controlled by enterprise policy).
  static bool IsEnabled(content::WebContents* web_contents);

  // Data scoped to a single page. PageData has the same lifetime as the page's
  // main document.
  class PageData : public content::PageUserData<PageData> {
   public:
    explicit PageData(content::Page& page);

    PageData(const PageData&) = delete;
    PageData& operator=(const PageData&) = delete;

    // Logs UMA in the destructor based on the number of popups blocked.
    ~PageData() override;

    void inc_num_popups_blocked() { ++num_popups_blocked_; }

    void set_is_triggered(bool is_triggered) { is_triggered_ = is_triggered; }
    bool is_triggered() const { return is_triggered_; }

    PAGE_USER_DATA_KEY_DECL();

   private:
    // How many popups are blocked in this page.
    int num_popups_blocked_ = 0;

    // Whether the current committed page load should trigger the stronger popup
    // blocker.
    bool is_triggered_ = false;
  };

  class NavigationHandleData
      : public content::NavigationHandleUserData<NavigationHandleData> {
   public:
    explicit NavigationHandleData(content::NavigationHandle&);
    ~NavigationHandleData() override;

    std::optional<safe_browsing::SubresourceFilterLevel>&
    level_for_next_committed_navigation() {
      return level_for_next_committed_navigation_;
    }

    NAVIGATION_HANDLE_USER_DATA_KEY_DECL();

   private:
    // Whether this navigation should trigger the stronger popup blocker in
    // enforce or warn mode.
    std::optional<safe_browsing::SubresourceFilterLevel>
        level_for_next_committed_navigation_;
  };

  // Returns the PageData for the specified |page|.
  PageData& GetPageData(content::Page& page);

  base::ScopedObservation<subresource_filter::SubresourceFilterObserverManager,
                          subresource_filter::SubresourceFilterObserver>
      scoped_observation_{this};

  WEB_CONTENTS_USER_DATA_KEY_DECL();
};

}  // namespace blocked_content

#endif  // COMPONENTS_BLOCKED_CONTENT_SAFE_BROWSING_TRIGGERED_POPUP_BLOCKER_H_