// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROME_BROWSER_CHROMEOS_MAHI_MAHI_WEB_CONTENTS_MANAGER_H_
#define CHROME_BROWSER_CHROMEOS_MAHI_MAHI_WEB_CONTENTS_MANAGER_H_
#include <memory>
#include <string>
#include "base/memory/weak_ptr.h"
#include "base/no_destructor.h"
#include "base/timer/timer.h"
#include "base/unguessable_token.h"
#include "chrome/browser/chromeos/mahi/mahi_browser_client_impl.h"
#include "chrome/browser/chromeos/mahi/mahi_browser_util.h"
#include "chrome/browser/chromeos/mahi/mahi_content_extraction_delegate.h"
#include "chrome/browser/content_extraction/inner_text.h"
#include "chromeos/crosapi/mojom/mahi.mojom-forward.h"
#include "content/public/browser/scoped_accessibility_mode.h"
#include "content/public/browser/web_contents_observer.h"
#include "ui/accessibility/ax_tree_update.h"
#include "ui/gfx/image/image_skia.h"
#include "url/gurl.h"
namespace content {
class WebContents;
} // namespace content
namespace mahi {
class ScopedMahiWebContentsManagerForTesting;
class MockMahiWebContentsManager;
class FakeMahiWebContentsManager;
using GetContentCallback =
base::OnceCallback<void(crosapi::mojom::MahiPageContentPtr)>;
// MahiPDFObserver is a helper class that observes the accessibility change from
// the PDF. The accessibility updates will then be used to extract the content
// of PDFs.
class MahiPDFObserver : public content::WebContentsObserver {
public:
using PDFContentObservedCallback =
base::OnceCallback<void(const std::vector<ui::AXTreeUpdate>&)>;
MahiPDFObserver(content::WebContents* web_contents,
ui::AXMode accessibility_mode,
ui::AXTreeID tree_id,
PDFContentObservedCallback callback);
MahiPDFObserver(const MahiPDFObserver&) = delete;
MahiPDFObserver& operator=(const MahiPDFObserver&) = delete;
~MahiPDFObserver() override;
// content::WebContentsObserver:
void AccessibilityEventReceived(
const ui::AXUpdatesAndEvents& details) override;
private:
// Timer to stop the observation if it's taking too long.
void OnTimerFired();
base::OneShotTimer timer_;
// ID of the tree that contains the PDF.
const ui::AXTreeID tree_id_;
// Callback to extract the content from update.
PDFContentObservedCallback callback_;
// Store the updates of the tree that contain the PDF.
std::vector<ui::AXTreeUpdate> updates_;
// Enables the accessibility mode for PDF content.
std::unique_ptr<content::ScopedAccessibilityMode> scoped_accessibility_mode_;
base::WeakPtrFactory<MahiPDFObserver> weak_ptr_factory_{this};
};
// `MahiWebContentsManager` is the central class for mahi web contents in the
// browser (ash and lacros) responsible for:
// 1. Being the single source of truth for mahi browser parameters like focused
// web page, the lasted extracted web page, etc. and providing this
// information to ChromeOS backend as needed.
// 2. Decides the distillability of a web page and extract contents from a
// requested web page.
class MahiWebContentsManager {
public:
MahiWebContentsManager(const MahiWebContentsManager&) = delete;
MahiWebContentsManager& operator=(const MahiWebContentsManager&) = delete;
static MahiWebContentsManager* Get();
void Initialize();
// Called when the focused tab finish loading.
// Virtual so we can override in tests.
virtual void OnFocusedPageLoadComplete(content::WebContents* web_contents);
// Clears the focused web content state, and notifies mahi manager.
// Passes the `top_level_window` downstream if it is set. This may suppress
// the notification if it is a media app window that is observed by media app
// content manager.
void ClearFocusedWebContentState(
raw_ptr<aura::Window> top_level_window = nullptr);
// Clears the focused web content and its state if the focused content is
// destroyed.
void WebContentsDestroyed(content::WebContents* web_contents);
// Called when the browser context menu has been clicked by the user.
// `question` is used only if `ButtonType` is kQA.
// Virtual so we can override in tests.
virtual void OnContextMenuClicked(int64_t display_id,
chromeos::mahi::ButtonType button_type,
const std::u16string& question,
const gfx::Rect& mahi_menu_bounds);
// Returns boolean to indicate if the current focused page is distillable. The
// default return is false, for the cases when the focused page's
// distillability has not been checked yet.
bool IsFocusedPageDistillable();
// Virtual so that can be overridden in test.
virtual bool GetPrefValue() const;
void set_mahi_pref_lacros(bool value) { mahi_pref_lacros_ = value; }
private:
friend base::NoDestructor<MahiWebContentsManager>;
// Friends to access some test-only functions.
friend class ScopedMahiWebContentsManagerForTesting;
friend class MockMahiWebContentsManager;
friend class FakeMahiWebContentsManager;
static void SetInstanceForTesting(MahiWebContentsManager* manager);
static void ResetInstanceForTesting();
MahiWebContentsManager();
virtual ~MahiWebContentsManager();
void OnGetInnerText(
const base::UnguessableToken& page_id,
const base::Time& start_time,
std::unique_ptr<content_extraction::InnerTextResult> result);
void OnGetSnapshot(const base::UnguessableToken& page_id,
content::WebContents* web_contents,
const base::Time& start_time,
GetContentCallback callback,
ui::AXTreeUpdate& snapshot);
void OnFinishDistillableCheck(const base::UnguessableToken& page_id,
bool is_distillable);
// Callback function of the user request from the OS side to get the page
// content.
void RequestContent(const base::UnguessableToken& page_id,
GetContentCallback callback);
// Get the page content of normal web pages.
void RequestWebContent(const base::UnguessableToken& page_id,
GetContentCallback callback);
// Get the content of PDFs.
void RequestPDFContent(const base::UnguessableToken& page_id,
GetContentCallback callback);
// Process the AXTreeUpdates received for PDF contents.
void OnGetAXTreeUpdatesForPDF(GetContentCallback callback,
const std::vector<ui::AXTreeUpdate>& updates);
// Gets the favicon from the given web contents. Returns an empty imageskia if
// there is no valid one.
// Virtual so we can override in tests.
virtual gfx::ImageSkia GetFavicon(content::WebContents* web_contents) const;
// Determines if the given web contents should be skipped for distillability
// check.
bool ShouldSkip(content::WebContents* web_contents);
std::unique_ptr<MahiContentExtractionDelegate> content_extraction_delegate_;
std::unique_ptr<MahiBrowserClientImpl> client_;
bool is_initialized_ = false;
bool mahi_pref_lacros_ = false;
// The state of the web content which get focus in the browser.
WebContentState focused_web_content_state_{/*url=*/GURL(), /*title=*/u""};
raw_ptr<content::WebContents> focused_web_contents_;
// Store if the current focused web contents is PDF.
bool is_pdf_focused_web_contents_ = false;
// Observer to observe accessibility changed on PDFs.
std::unique_ptr<MahiPDFObserver> pdf_observer_;
base::WeakPtrFactory<MahiWebContentsManager> weak_pointer_factory_{this};
};
} // namespace mahi
#endif // CHROME_BROWSER_CHROMEOS_MAHI_MAHI_WEB_CONTENTS_MANAGER_H_
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