// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/browser/extensions/api/automation_internal/automation_internal_api.h"

#include <stdint.h>

#include <memory>
#include <vector>

#include "base/macros.h"
#include "base/strings/string16.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/utf_string_conversions.h"
#include "chrome/browser/extensions/api/automation_internal/automation_event_router.h"
#include "chrome/browser/extensions/api/tabs/tabs_constants.h"
#include "chrome/browser/extensions/chrome_extension_function_details.h"
#include "chrome/browser/extensions/extension_tab_util.h"
#include "chrome/browser/profiles/profile.h"
#include "chrome/browser/ui/browser.h"
#include "chrome/browser/ui/tabs/tab_strip_model.h"
#include "chrome/common/extensions/api/automation.h"
#include "chrome/common/extensions/api/automation_internal.h"
#include "chrome/common/extensions/chrome_extension_messages.h"
#include "content/public/browser/ax_event_notification_details.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/media_session.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/browser/render_widget_host.h"
#include "content/public/browser/render_widget_host_view.h"
#include "content/public/browser/web_contents.h"
#include "content/public/browser/web_contents_observer.h"
#include "content/public/browser/web_contents_user_data.h"
#include "extensions/common/extension_messages.h"
#include "extensions/common/manifest_handlers/automation.h"
#include "extensions/common/permissions/permissions_data.h"
#include "ui/accessibility/ax_action_data.h"
#include "ui/accessibility/ax_action_handler.h"
#include "ui/accessibility/ax_enum_util.h"
#include "ui/accessibility/ax_tree_id_registry.h"

#if defined(USE_AURA)
#include "chrome/browser/ui/aura/accessibility/automation_manager_aura.h"
#include "ui/aura/env.h"
#endif

namespace extensions {
class AutomationWebContentsObserver;
}  // namespace extensions

namespace extensions {

namespace {

const char kCannotRequestAutomationOnPage[] =
    "Cannot request automation tree on url \"*\". "
    "Extension manifest must request permission to access this host.";
const char kRendererDestroyed[] = "The tab was closed.";
const char kNoDocument[] = "No document.";
const char kNodeDestroyed[] =
    "domQuerySelector sent on node which is no longer in the tree.";

// Handles sending and receiving IPCs for a single querySelector request. On
// creation, sends the request IPC, and is destroyed either when the response is
// received or the renderer is destroyed.
class QuerySelectorHandler : public content::WebContentsObserver {
 public:
  QuerySelectorHandler(
      content::WebContents* web_contents,
      int request_id,
      int acc_obj_id,
      const base::string16& query,
      const extensions::AutomationInternalQuerySelectorFunction::Callback&
          callback)
      : content::WebContentsObserver(web_contents),
        request_id_(request_id),
        callback_(callback) {
    content::RenderFrameHost* rfh = web_contents->GetMainFrame();

    rfh->Send(new ExtensionMsg_AutomationQuerySelector(
        rfh->GetRoutingID(), request_id, acc_obj_id, query));
  }

  ~QuerySelectorHandler() override {}

  bool OnMessageReceived(const IPC::Message& message,
                         content::RenderFrameHost* render_frame_host) override {
    if (message.type() != ExtensionHostMsg_AutomationQuerySelector_Result::ID)
      return false;

    // There may be several requests in flight; check this response matches.
    int message_request_id = 0;
    base::PickleIterator iter(message);
    if (!iter.ReadInt(&message_request_id))
      return false;

    if (message_request_id != request_id_)
      return false;

    IPC_BEGIN_MESSAGE_MAP(QuerySelectorHandler, message)
      IPC_MESSAGE_HANDLER(ExtensionHostMsg_AutomationQuerySelector_Result,
                          OnQueryResponse)
    IPC_END_MESSAGE_MAP()
    return true;
  }

  void WebContentsDestroyed() override {
    callback_.Run(kRendererDestroyed, 0);
    delete this;
  }

 private:
  void OnQueryResponse(int request_id,
                       ExtensionHostMsg_AutomationQuerySelector_Error error,
                       int result_acc_obj_id) {
    std::string error_string;
    switch (error.value) {
      case ExtensionHostMsg_AutomationQuerySelector_Error::kNone:
        break;
      case ExtensionHostMsg_AutomationQuerySelector_Error::kNoDocument:
        error_string = kNoDocument;
        break;
      case ExtensionHostMsg_AutomationQuerySelector_Error::kNodeDestroyed:
        error_string = kNodeDestroyed;
        break;
    }
    callback_.Run(error_string, result_acc_obj_id);
    delete this;
  }

  int request_id_;
  const extensions::AutomationInternalQuerySelectorFunction::Callback callback_;
};

bool CanRequestAutomation(const Extension* extension,
                          const AutomationInfo* automation_info,
                          content::WebContents* contents) {
  if (automation_info->desktop)
    return true;

  const GURL& url = contents->GetURL();
  // TODO(aboxhall): check for webstore URL
  if (automation_info->matches.MatchesURL(url))
    return true;

  int tab_id = ExtensionTabUtil::GetTabId(contents);
  std::string unused_error;
  return extension->permissions_data()->CanAccessPage(url, tab_id,
                                                      &unused_error);
}

}  // namespace

// Helper class that receives accessibility data from |WebContents|.
class AutomationWebContentsObserver
    : public content::WebContentsObserver,
      public content::WebContentsUserData<AutomationWebContentsObserver> {
 public:
  ~AutomationWebContentsObserver() override {}

  // content::WebContentsObserver overrides.
  void AccessibilityEventReceived(const content::AXEventNotificationDetails&
                                      content_event_bundle) override {
    ExtensionMsg_AccessibilityEventBundleParams extension_event_bundle;
    extension_event_bundle.updates = content_event_bundle.updates;
    extension_event_bundle.events = content_event_bundle.events;
    extension_event_bundle.tree_id = content_event_bundle.ax_tree_id;
#if defined(USE_AURA)
    extension_event_bundle.mouse_location =
        aura::Env::GetInstance()->last_mouse_location();
#endif
    AutomationEventRouter* router = AutomationEventRouter::GetInstance();
    router->DispatchAccessibilityEvents(extension_event_bundle);
  }

  void AccessibilityLocationChangesReceived(
      const std::vector<content::AXLocationChangeNotificationDetails>& details)
      override {
    for (const auto& src : details) {
      ExtensionMsg_AccessibilityLocationChangeParams dst;
      dst.id = src.id;
      dst.tree_id = src.ax_tree_id;
      dst.new_location = src.new_location;
      AutomationEventRouter* router = AutomationEventRouter::GetInstance();
      router->DispatchAccessibilityLocationChange(dst);
    }
  }

  void RenderFrameDeleted(
      content::RenderFrameHost* render_frame_host) override {
    ui::AXTreeID tree_id = render_frame_host->GetAXTreeID();
    AutomationEventRouter::GetInstance()->DispatchTreeDestroyedEvent(
        tree_id,
        browser_context_);
  }

  void MediaStartedPlaying(const MediaPlayerInfo& video_type,
                           const MediaPlayerId& id) override {
    content::AXEventNotificationDetails content_event_bundle;
    content_event_bundle.ax_tree_id = id.render_frame_host->GetAXTreeID();
    content_event_bundle.events.resize(1);
    content_event_bundle.events[0].event_type =
        ax::mojom::Event::kMediaStartedPlaying;
    AccessibilityEventReceived(content_event_bundle);
  }

  void MediaStoppedPlaying(
      const MediaPlayerInfo& video_type,
      const MediaPlayerId& id,
      WebContentsObserver::MediaStoppedReason reason) override {
    content::AXEventNotificationDetails content_event_bundle;
    content_event_bundle.ax_tree_id = id.render_frame_host->GetAXTreeID();
    content_event_bundle.events.resize(1);
    content_event_bundle.events[0].event_type =
        ax::mojom::Event::kMediaStoppedPlaying;
    AccessibilityEventReceived(content_event_bundle);
  }

 private:
  friend class content::WebContentsUserData<AutomationWebContentsObserver>;

  explicit AutomationWebContentsObserver(content::WebContents* web_contents)
      : content::WebContentsObserver(web_contents),
        browser_context_(web_contents->GetBrowserContext()) {
    if (web_contents->IsCurrentlyAudible()) {
      content::RenderFrameHost* rfh = web_contents->GetMainFrame();
      if (!rfh)
        return;

      content::AXEventNotificationDetails content_event_bundle;
      content_event_bundle.ax_tree_id = rfh->GetAXTreeID();
      content_event_bundle.events.resize(1);
      content_event_bundle.events[0].event_type =
          ax::mojom::Event::kMediaStartedPlaying;
      AccessibilityEventReceived(content_event_bundle);
    }
  }

  content::BrowserContext* browser_context_;

  WEB_CONTENTS_USER_DATA_KEY_DECL();

  DISALLOW_COPY_AND_ASSIGN(AutomationWebContentsObserver);
};

WEB_CONTENTS_USER_DATA_KEY_IMPL(AutomationWebContentsObserver)

ExtensionFunction::ResponseAction
AutomationInternalEnableTabFunction::Run() {
  const AutomationInfo* automation_info = AutomationInfo::Get(extension());
  EXTENSION_FUNCTION_VALIDATE(automation_info);

  using api::automation_internal::EnableTab::Params;
  std::unique_ptr<Params> params(Params::Create(*args_));
  EXTENSION_FUNCTION_VALIDATE(params.get());
  content::WebContents* contents = NULL;
  if (params->args.tab_id.get()) {
    int tab_id = *params->args.tab_id;
    if (!ExtensionTabUtil::GetTabById(
            tab_id, browser_context(), include_incognito_information(),
            NULL, /* browser out param*/
            NULL, /* tab_strip out param */
            &contents, NULL /* tab_index out param */)) {
      return RespondNow(
          Error(tabs_constants::kTabNotFoundError, base::IntToString(tab_id)));
    }
  } else {
    contents = ChromeExtensionFunctionDetails(this)
                   .GetCurrentBrowser()
                   ->tab_strip_model()
                   ->GetActiveWebContents();
    if (!contents)
      return RespondNow(Error("No active tab"));
  }

  content::RenderFrameHost* rfh = contents->GetMainFrame();
  if (!rfh)
    return RespondNow(Error("Could not enable accessibility for active tab"));

  if (!CanRequestAutomation(extension(), automation_info, contents)) {
    return RespondNow(
        Error(kCannotRequestAutomationOnPage, contents->GetURL().spec()));
  }

  AutomationWebContentsObserver::CreateForWebContents(contents);
  contents->EnableWebContentsOnlyAccessibilityMode();

  ui::AXTreeID ax_tree_id = rfh->GetAXTreeID();

  // This gets removed when the extension process dies.
  AutomationEventRouter::GetInstance()->RegisterListenerForOneTree(
      extension_id(),
      source_process_id(),
      ax_tree_id);

  return RespondNow(
      ArgumentList(api::automation_internal::EnableTab::Results::Create(
          ax_tree_id.ToString())));
}

ExtensionFunction::ResponseAction AutomationInternalEnableFrameFunction::Run() {
  // TODO(dtseng): Limited to desktop tree for now pending out of proc iframes.
  using api::automation_internal::EnableFrame::Params;

  std::unique_ptr<Params> params(Params::Create(*args_));
  EXTENSION_FUNCTION_VALIDATE(params.get());

  content::RenderFrameHost* rfh = content::RenderFrameHost::FromAXTreeID(
      ui::AXTreeID::FromString(params->tree_id));
  if (!rfh)
    return RespondNow(Error("unable to load tab"));

  content::WebContents* contents =
      content::WebContents::FromRenderFrameHost(rfh);
  AutomationWebContentsObserver::CreateForWebContents(contents);

  // Only call this if this is the root of a frame tree, to avoid resetting
  // the accessibility state multiple times.
  if (!rfh->GetParent())
    contents->EnableWebContentsOnlyAccessibilityMode();

  return RespondNow(NoArguments());
}

ExtensionFunction::ResponseAction
AutomationInternalPerformActionFunction::ConvertToAXActionData(
    api::automation_internal::PerformAction::Params* params,
    ui::AXActionData* action) {
  action->target_tree_id = ui::AXTreeID::FromString(params->args.tree_id);
  action->source_extension_id = extension_id();
  action->target_node_id = params->args.automation_node_id;
  int* request_id = params->args.request_id.get();
  action->request_id = request_id ? *request_id : -1;
  api::automation::ActionType action_type =
      api::automation::ParseActionType(params->args.action_type);
  switch (action_type) {
    case api::automation::ACTION_TYPE_BLUR:
      action->action = ax::mojom::Action::kBlur;
      break;
    case api::automation::ACTION_TYPE_CLEARACCESSIBILITYFOCUS:
      action->action = ax::mojom::Action::kClearAccessibilityFocus;
      break;
    case api::automation::ACTION_TYPE_DECREMENT:
      action->action = ax::mojom::Action::kDecrement;
      break;
    case api::automation::ACTION_TYPE_DODEFAULT:
      action->action = ax::mojom::Action::kDoDefault;
      break;
    case api::automation::ACTION_TYPE_INCREMENT:
      action->action = ax::mojom::Action::kIncrement;
      break;
    case api::automation::ACTION_TYPE_FOCUS:
      action->action = ax::mojom::Action::kFocus;
      break;
    case api::automation::ACTION_TYPE_GETIMAGEDATA: {
      api::automation_internal::GetImageDataParams get_image_data_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::GetImageDataParams::Populate(
              params->opt_args.additional_properties, &get_image_data_params));
      action->action = ax::mojom::Action::kGetImageData;
      action->target_rect = gfx::Rect(0, 0, get_image_data_params.max_width,
                                      get_image_data_params.max_height);
      break;
    }
    case api::automation::ACTION_TYPE_HITTEST: {
      api::automation_internal::HitTestParams hit_test_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::HitTestParams::Populate(
              params->opt_args.additional_properties, &hit_test_params));
      action->action = ax::mojom::Action::kHitTest;
      action->target_point = gfx::Point(hit_test_params.x, hit_test_params.y);
      action->hit_test_event_to_fire =
          ui::ParseEvent(hit_test_params.event_to_fire.c_str());
      if (action->hit_test_event_to_fire == ax::mojom::Event::kNone)
        return RespondNow(NoArguments());
      break;
    }
    case api::automation::ACTION_TYPE_LOADINLINETEXTBOXES:
      action->action = ax::mojom::Action::kLoadInlineTextBoxes;
      break;
    case api::automation::ACTION_TYPE_SETACCESSIBILITYFOCUS:
      action->action = ax::mojom::Action::kSetAccessibilityFocus;
      break;
    case api::automation::ACTION_TYPE_SCROLLTOMAKEVISIBLE:
      action->action = ax::mojom::Action::kScrollToMakeVisible;
      break;
    case api::automation::ACTION_TYPE_SCROLLBACKWARD:
      action->action = ax::mojom::Action::kScrollBackward;
      break;
    case api::automation::ACTION_TYPE_SCROLLFORWARD:
      action->action = ax::mojom::Action::kScrollForward;
      break;
    case api::automation::ACTION_TYPE_SCROLLUP:
      action->action = ax::mojom::Action::kScrollUp;
      break;
    case api::automation::ACTION_TYPE_SCROLLDOWN:
      action->action = ax::mojom::Action::kScrollDown;
      break;
    case api::automation::ACTION_TYPE_SCROLLLEFT:
      action->action = ax::mojom::Action::kScrollLeft;
      break;
    case api::automation::ACTION_TYPE_SCROLLRIGHT:
      action->action = ax::mojom::Action::kScrollRight;
      break;
    case api::automation::ACTION_TYPE_SETSELECTION: {
      api::automation_internal::SetSelectionParams selection_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::SetSelectionParams::Populate(
              params->opt_args.additional_properties, &selection_params));
      action->anchor_node_id = params->args.automation_node_id;
      action->anchor_offset = selection_params.anchor_offset;
      action->focus_node_id = selection_params.focus_node_id;
      action->focus_offset = selection_params.focus_offset;
      action->action = ax::mojom::Action::kSetSelection;
      break;
    }
    case api::automation::ACTION_TYPE_SHOWCONTEXTMENU: {
      action->action = ax::mojom::Action::kShowContextMenu;
      break;
    }
    case api::automation::
        ACTION_TYPE_SETSEQUENTIALFOCUSNAVIGATIONSTARTINGPOINT: {
      action->action =
          ax::mojom::Action::kSetSequentialFocusNavigationStartingPoint;
      break;
    }
    case api::automation::ACTION_TYPE_CUSTOMACTION: {
      api::automation_internal::PerformCustomActionParams
          perform_custom_action_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::PerformCustomActionParams::Populate(
              params->opt_args.additional_properties,
              &perform_custom_action_params));
      action->action = ax::mojom::Action::kCustomAction;
      action->custom_action_id = perform_custom_action_params.custom_action_id;
      break;
    }
    case api::automation::ACTION_TYPE_REPLACESELECTEDTEXT: {
      api::automation_internal::ReplaceSelectedTextParams
          replace_selected_text_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::ReplaceSelectedTextParams::Populate(
              params->opt_args.additional_properties,
              &replace_selected_text_params));
      action->action = ax::mojom::Action::kReplaceSelectedText;
      action->value = replace_selected_text_params.value;
      break;
    }
    case api::automation::ACTION_TYPE_SETVALUE: {
      api::automation_internal::SetValueParams set_value_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::SetValueParams::Populate(
              params->opt_args.additional_properties, &set_value_params));
      action->action = ax::mojom::Action::kSetValue;
      action->value = set_value_params.value;
      break;
    }
    // These actions are currently unused by any existing clients of
    // automation. They also require additional arguments to be plumbed
    // through (e.g. setValue takes a string value to be set). Future clients
    // may wish to extend the api to support these actions.
    case api::automation::ACTION_TYPE_SCROLLTOPOINT:
    case api::automation::ACTION_TYPE_SETSCROLLOFFSET:
      return RespondNow(
          Error("Unsupported action: " + params->args.action_type));
    case api::automation::ACTION_TYPE_GETTEXTLOCATION: {
      api::automation_internal::GetTextLocationDataParams
          get_text_location_params;
      EXTENSION_FUNCTION_VALIDATE(
          api::automation_internal::GetTextLocationDataParams::Populate(
              params->opt_args.additional_properties,
              &get_text_location_params));
      action->action = ax::mojom::Action::kGetTextLocation;
      action->start_index = get_text_location_params.start_index;
      action->end_index = get_text_location_params.end_index;
      break;
    }
    case api::automation::ACTION_TYPE_NONE:
      break;
  }
  return RespondNow(NoArguments());
}

ExtensionFunction::ResponseAction
AutomationInternalPerformActionFunction::Run() {
  const AutomationInfo* automation_info = AutomationInfo::Get(extension());
  EXTENSION_FUNCTION_VALIDATE(automation_info && automation_info->interact);

  using api::automation_internal::PerformAction::Params;
  std::unique_ptr<Params> params(Params::Create(*args_));
  EXTENSION_FUNCTION_VALIDATE(params.get());
  ui::AXTreeIDRegistry* registry = ui::AXTreeIDRegistry::GetInstance();
  ui::AXActionHandler* action_handler = registry->GetActionHandler(
      ui::AXTreeID::FromString(params->args.tree_id));
  if (action_handler) {
    // Handle an AXActionHandler with a rfh first. Some actions require a rfh ->
    // web contents and this api requires web contents to perform a permissions
    // check.
    content::RenderFrameHost* rfh = content::RenderFrameHost::FromAXTreeID(
        ui::AXTreeID::FromString(params->args.tree_id));
    if (rfh) {
      content::WebContents* contents =
          content::WebContents::FromRenderFrameHost(rfh);
      if (!CanRequestAutomation(extension(), automation_info, contents)) {
        return RespondNow(
            Error(kCannotRequestAutomationOnPage, contents->GetURL().spec()));
      }

      // Handle internal actions.
      api::automation_internal::ActionTypePrivate internal_action_type =
          api::automation_internal::ParseActionTypePrivate(
              params->args.action_type);
      content::MediaSession* session = content::MediaSession::Get(contents);
      switch (internal_action_type) {
        case api::automation_internal::ACTION_TYPE_PRIVATE_STARTDUCKINGMEDIA:
          session->StartDucking();
          return RespondNow(NoArguments());
        case api::automation_internal::ACTION_TYPE_PRIVATE_STOPDUCKINGMEDIA:
          session->StopDucking();
          return RespondNow(NoArguments());
        case api::automation_internal::ACTION_TYPE_PRIVATE_RESUMEMEDIA:
          session->Resume(content::MediaSession::SuspendType::kSystem);
          return RespondNow(NoArguments());
        case api::automation_internal::ACTION_TYPE_PRIVATE_SUSPENDMEDIA:
          session->Suspend(content::MediaSession::SuspendType::kSystem);
          return RespondNow(NoArguments());
        case api::automation_internal::ACTION_TYPE_PRIVATE_NONE:
          // Not a private action.
          break;
      }
    }

    ui::AXActionData data;
    ExtensionFunction::ResponseAction result =
        ConvertToAXActionData(params.get(), &data);
    action_handler->PerformAction(data);
    return result;
  }
  return RespondNow(Error("Unable to perform action on unknown tree."));
}

ExtensionFunction::ResponseAction
AutomationInternalEnableDesktopFunction::Run() {
#if defined(USE_AURA)
  const AutomationInfo* automation_info = AutomationInfo::Get(extension());
  if (!automation_info || !automation_info->desktop)
    return RespondNow(Error("desktop permission must be requested"));

  // This gets removed when the extension process dies.
  AutomationEventRouter::GetInstance()->RegisterListenerWithDesktopPermission(
      extension_id(), source_process_id());

  AutomationManagerAura::GetInstance()->Enable();
  ui::AXTreeID ax_tree_id = AutomationManagerAura::GetInstance()->ax_tree_id();
  return RespondNow(
      ArgumentList(api::automation_internal::EnableDesktop::Results::Create(
          ax_tree_id.ToString())));
#else
  return RespondNow(Error("getDesktop is unsupported by this platform"));
#endif  // defined(USE_AURA)
}

// static
int AutomationInternalQuerySelectorFunction::query_request_id_counter_ = 0;

ExtensionFunction::ResponseAction
AutomationInternalQuerySelectorFunction::Run() {
  const AutomationInfo* automation_info = AutomationInfo::Get(extension());
  EXTENSION_FUNCTION_VALIDATE(automation_info);

  using api::automation_internal::QuerySelector::Params;
  std::unique_ptr<Params> params(Params::Create(*args_));
  EXTENSION_FUNCTION_VALIDATE(params.get());

  content::RenderFrameHost* rfh = content::RenderFrameHost::FromAXTreeID(
      ui::AXTreeID::FromString(params->args.tree_id));
  if (!rfh) {
    return RespondNow(
        Error("domQuerySelector query sent on non-web or destroyed tree."));
  }

  content::WebContents* contents =
      content::WebContents::FromRenderFrameHost(rfh);

  int request_id = query_request_id_counter_++;
  base::string16 selector = base::UTF8ToUTF16(params->args.selector);

  // QuerySelectorHandler handles IPCs and deletes itself on completion.
  new QuerySelectorHandler(
      contents, request_id, params->args.automation_node_id, selector,
      base::Bind(&AutomationInternalQuerySelectorFunction::OnResponse, this));

  return RespondLater();
}

void AutomationInternalQuerySelectorFunction::OnResponse(
    const std::string& error,
    int result_acc_obj_id) {
  if (!error.empty()) {
    Respond(Error(error));
    return;
  }

  Respond(OneArgument(std::make_unique<base::Value>(result_acc_obj_id)));
}

}  // namespace extensions