// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/public/test/accessibility_notification_waiter.h"

#include "base/functional/bind.h"
#include "base/logging.h"
#include "base/no_destructor.h"
#include "base/run_loop.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "content/browser/renderer_host/render_frame_host_impl.h"
#include "content/browser/renderer_host/render_widget_host_view_base.h"
#include "content/browser/web_contents/web_contents_impl.h"
#include "content/public/browser/browser_accessibility_state.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/browser_plugin_guest_manager.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/web_contents.h"
#include "content/public/test/test_utils.h"
#include "ui/accessibility/ax_node.h"
#include "ui/accessibility/platform/browser_accessibility.h"
#include "ui/accessibility/platform/browser_accessibility_manager.h"

namespace content {

AccessibilityNotificationWaiter::AccessibilityNotificationWaiter(
    WebContents* web_contents)
    : WebContentsObserver(web_contents),
      event_to_wait_for_(ax::mojom::Event::kNone),
      loop_runner_(std::make_unique<base::RunLoop>()),
      loop_runner_quit_closure_(loop_runner_->QuitClosure()),
      wait_for_any_event_(true) {
  ListenToAllFrames(web_contents);
}

AccessibilityNotificationWaiter::AccessibilityNotificationWaiter(
    WebContents* web_contents,
    ax::mojom::Event event)
    : WebContentsObserver(web_contents),
      event_to_wait_for_(event),
      loop_runner_(std::make_unique<base::RunLoop>()),
      loop_runner_quit_closure_(loop_runner_->QuitClosure()) {
  ListenToAllFrames(web_contents);
}

AccessibilityNotificationWaiter::AccessibilityNotificationWaiter(
    WebContents* web_contents,
    ui::AXEventGenerator::Event event_type)
    : WebContentsObserver(web_contents),
      generated_event_to_wait_for_(event_type),
      loop_runner_(std::make_unique<base::RunLoop>()),
      loop_runner_quit_closure_(loop_runner_->QuitClosure()) {
  ListenToAllFrames(web_contents);
}

AccessibilityNotificationWaiter::~AccessibilityNotificationWaiter() = default;

void AccessibilityNotificationWaiter::ListenToAllFrames(
    WebContents* web_contents) {
  if (event_to_wait_for_)
    VLOG(1) << "Waiting for AccessibilityEvent " << *event_to_wait_for_;
  WebContentsImpl* web_contents_impl =
      static_cast<WebContentsImpl*>(web_contents);

  FrameTree::NodeRange nodes =
      web_contents_impl->GetPrimaryFrameTree().NodesIncludingInnerTreeNodes();
  for (FrameTreeNode* node : nodes) {
    frame_count_++;
    ListenToFrame(node->current_frame_host());
  }

  if (!base::FeatureList::IsEnabled(features::kGuestViewMPArch)) {
    BrowserPluginGuestManager* guest_manager =
        web_contents_impl->GetBrowserContext()->GetGuestManager();
    if (guest_manager) {
      guest_manager->ForEachGuest(web_contents_impl,
                                  [&](WebContents* web_contents) {
                                    ListenToAllFrames(web_contents);
                                    return true;
                                  });
    }
  }
}

void AccessibilityNotificationWaiter::ListenToFrame(
    RenderFrameHostImpl* frame_host) {
  if (event_to_wait_for_ || wait_for_any_event_) {
    BindOnAccessibilityEvent(frame_host);
  }
  if (generated_event_to_wait_for_ || wait_for_any_event_) {
    BindOnGeneratedEvent(frame_host);
  }

  if (event_to_wait_for_ == ax::mojom::Event::kNone ||
      event_to_wait_for_ == ax::mojom::Event::kLocationChanged ||
      wait_for_any_event_) {
    BindOnLocationsChanged(frame_host);
  }
}

bool AccessibilityNotificationWaiter::WaitForNotification(bool all_frames) {
  if (all_frames) {
    notification_count_ = 0;
  } else {
    // Pretend we've heard all the notifications but one, so that the first
    // notification allows us to stop waiting.
    notification_count_ = frame_count_ - 1;
  }
  loop_runner_->Run();

  bool notification_received = notification_received_;
  // Reset everything to allow reuse.
  // Each loop runner can only be called once. Create a new one in case
  // the caller wants to call this again to wait for the next notification.
  loop_runner_ = std::make_unique<base::RunLoop>();
  loop_runner_quit_closure_ = loop_runner_->QuitClosure();
  notification_received_ = false;

  return notification_received;
}

bool AccessibilityNotificationWaiter::WaitForNotificationWithTimeout(
    base::TimeDelta timeout) {
  base::OneShotTimer quit_timer;
  quit_timer.Start(FROM_HERE, timeout, loop_runner_->QuitWhenIdleClosure());

  return WaitForNotification();
}

const ui::AXTree& AccessibilityNotificationWaiter::GetAXTree() const {
  return GetAXTreeForFrame(
      static_cast<WebContentsImpl*>(web_contents())->GetPrimaryMainFrame());
}

void AccessibilityNotificationWaiter::BindOnAccessibilityEvent(
    RenderFrameHostImpl* frame_host) {
  frame_host->SetAccessibilityCallbackForTesting(base::BindRepeating(
      &AccessibilityNotificationWaiter::OnAccessibilityEvent,
      weak_factory_.GetWeakPtr()));
}

void AccessibilityNotificationWaiter::OnAccessibilityEvent(
    RenderFrameHostImpl* rfhi,
    ax::mojom::Event event_type,
    int event_target_id) {
  VLOG(1) << "OnAccessibilityEvent " << event_type;

  if (event_to_wait_for_ == ax::mojom::Event::kNone ||
      event_to_wait_for_ == event_type || wait_for_any_event_) {
    event_target_id_ = event_target_id;
    event_browser_accessibility_manager_ =
        rfhi ? rfhi->GetOrCreateBrowserAccessibilityManager() : nullptr;
    notification_count_++;
    if (notification_count_ == frame_count_) {
      notification_received_ = true;
      loop_runner_quit_closure_.Run();
    }
  }
}

void AccessibilityNotificationWaiter::BindOnGeneratedEvent(
    RenderFrameHostImpl* frame_host) {
  if (auto* manager = frame_host->GetOrCreateBrowserAccessibilityManager()) {
    manager->SetGeneratedEventCallbackForTesting(
        base::BindRepeating(&AccessibilityNotificationWaiter::OnGeneratedEvent,
                            weak_factory_.GetWeakPtr()));
    manager->SetFocusChangeCallbackForTesting(
        base::BindRepeating(&AccessibilityNotificationWaiter::OnFocusChanged,
                            weak_factory_.GetWeakPtr()));
  }
}

void AccessibilityNotificationWaiter::BindOnLocationsChanged(
    RenderFrameHostImpl* frame_host) {
  if (auto* manager = frame_host->browser_accessibility_manager()) {
    manager->SetLocationChangeCallbackForTesting(base::BindRepeating(
        &AccessibilityNotificationWaiter::OnLocationsChanged,
        weak_factory_.GetWeakPtr()));
  }
}

void AccessibilityNotificationWaiter::OnGeneratedEvent(
    ui::BrowserAccessibilityManager* manager,
    ui::AXEventGenerator::Event event,
    ui::AXNodeID event_target_id) {
  DCHECK(manager);
  DCHECK_NE(event_target_id, ui::kInvalidAXNodeID);
  VLOG(1) << "OnGeneratedEvent " << event;

  if (generated_event_to_wait_for_ == event || wait_for_any_event_) {
    event_target_id_ = event_target_id;
    event_browser_accessibility_manager_ = manager;
    notification_count_++;
    if (notification_count_ == frame_count_) {
      notification_received_ = true;
      loop_runner_quit_closure_.Run();
    }
  }
}

void AccessibilityNotificationWaiter::OnLocationsChanged() {
  notification_received_ = true;
  loop_runner_quit_closure_.Run();
}

// TODO(crbug.com/41470112): Remove this method once we migrate to using
// AXEventGenerator for focus changed events.
void AccessibilityNotificationWaiter::OnFocusChanged() {
  WebContentsImpl* web_contents_impl =
      static_cast<WebContentsImpl*>(web_contents());
  ui::BrowserAccessibilityManager* manager =
      web_contents_impl->GetRootBrowserAccessibilityManager();
  if (manager && manager->delegate() && manager->GetFocus()) {
    OnGeneratedEvent(manager, ui::AXEventGenerator::Event::FOCUS_CHANGED,
                     manager->GetFocus()->GetId());
  }
}

const ui::AXTree& AccessibilityNotificationWaiter::GetAXTreeForFrame(
    RenderFrameHostImpl* render_frame) const {
  static base::NoDestructor<ui::AXTree> empty_tree;
  WebContentsImpl* web_contents_impl =
      WebContentsImpl::FromRenderFrameHostImpl(render_frame);
  ui::BrowserAccessibilityManager* manager =
      web_contents_impl->GetRootBrowserAccessibilityManager();
  return manager && manager->ax_tree() ? *manager->ax_tree() : *empty_tree;
}

// WebContentsObserver override:
void AccessibilityNotificationWaiter::RenderFrameHostChanged(
    RenderFrameHost* old_host,
    RenderFrameHost* new_host) {
  ListenToFrame(static_cast<RenderFrameHostImpl*>(new_host));
}

void AccessibilityNotificationWaiter::Quit() {
  loop_runner_quit_closure_.Run();
}

}  // namespace content