// Copyright 2025 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_UI_WEBUI_SEARCHBOX_WEBUI_OMNIBOX_HANDLER_H_
#define CHROME_BROWSER_UI_WEBUI_SEARCHBOX_WEBUI_OMNIBOX_HANDLER_H_

#include "base/memory/weak_ptr.h"
#include "base/scoped_observation.h"
#include "chrome/browser/ui/omnibox/omnibox_edit_model.h"
#include "chrome/browser/ui/tabs/tab_strip_model_observer.h"
#include "chrome/browser/ui/webui/cr_components/searchbox/contextual_searchbox_handler.h"
#include "chrome/browser/ui/webui/top_chrome/top_chrome_web_ui_controller.h"
#include "components/omnibox/browser/autocomplete_input.h"
#include "components/omnibox/browser/omnibox_popup_selection.h"
#include "components/omnibox/browser/omnibox_prefs.h"
#include "components/omnibox/browser/searchbox.mojom.h"
#include "components/prefs/pref_change_registrar.h"
#include "content/public/browser/web_contents_observer.h"
#include "mojo/public/cpp/bindings/pending_receiver.h"
#include "mojo/public/cpp/bindings/receiver.h"
#include "mojo/public/cpp/bindings/remote.h"
#include "ui/base/window_open_disposition.h"

class MetricsReporter;
class OmniboxController;

struct AiModeButtonUiConfig;

namespace content {
class WebUI;
}  // namespace content

// Handles bidirectional communication between NTP realbox JS and the browser.
class WebuiOmniboxHandler : public ContextualSearchboxHandler,
                            OmniboxEditModel::Observer {
 public:
  WebuiOmniboxHandler(
      mojo::PendingReceiver<searchbox::mojom::PageHandler> pending_page_handler,
      mojo::PendingRemote<searchbox::mojom::Page> pending_page,
      MetricsReporter* metrics_reporter,
      OmniboxController* omnibox_controller,
      content::WebUI* web_ui,
      GetSessionHandleCallback get_session_callback);

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

  ~WebuiOmniboxHandler() override;

  // searchbox::mojom::PageHandler:
  void ActivateKeyword(uint8_t line,
                       const GURL& url,
                       base::TimeTicks match_selection_timestamp,
                       bool is_mouse_event) override;
  void OnThumbnailRemoved() override {}
  void OpenLensSearch() override;
  void AddTabContext(int32_t tab_id,
                     bool delay_upload,
                     searchbox::mojom::TabAttachmentSource source,
                     AddTabContextCallback) override;
  // Queries autocomplete matches from the browser:
  // - When the WebUI Omnibox full popup is enabled:
  //   - If targeting the active tab (or if `tab_id` is nullopt), triggers
  //     autocomplete and syncs the active native view text/caret.
  //   - If targeting a background tab (e.g., an in-flight IPC arriving after a
  //     tab switch), updates that background tab's saved draft state via
  //     `SetUserTextForTab` without running autocomplete or mutating the active
  //     view.
  // - When the full popup is disabled, requires `!tab_id.has_value()` and
  //   forwards directly to `SearchboxHandler::QueryAutocomplete`.
  void QueryAutocomplete(int32_t query_id,
                         std::optional<int32_t> tab_id,
                         const std::u16string& input,
                         bool prevent_inline_autocomplete,
                         uint32_t cursor_position,
                         omnibox::SuggestInventory suggest_inventory,
                         bool is_on_focus,
                         const std::string& keyword,
                         searchbox::mojom::InputMethod input_method) override;

  void StepSelection(OmniboxPopupSelection::Direction direction,
                     OmniboxPopupSelection::Step step);
  void OpenCurrentSelection(WindowOpenDisposition disposition);
  void SetAimButtonVisible(bool visible) override;

  // SearchboxHandler:
  WindowOpenDisposition ComputeWindowOpenDisposition(
      uint8_t mouse_button,
      bool alt_key,
      bool ctrl_key,
      bool meta_key,
      bool shift_key,
      bool via_keyboard) override;
  bool ShouldShowFirstContextualDescription() const override;
  bool SupportsKeywordMode() const override;
  void OverrideIconPaths(
      const AutocompleteMatch& match,
      searchbox::mojom::AutocompleteMatch* mojom_match) const override;
  void OnFocusChanged(bool focused) override;

  // AutocompleteController::Observer:
  void OnStart(AutocompleteController* controller,
               const AutocompleteInput& input) override;
  void OnResultChanged(AutocompleteController* controller,
                       bool default_match_changed) override;

  // OmniboxEditModel::Observer:
  void OnSelectionChanged(OmniboxPopupSelection old_selection,
                          OmniboxPopupSelection selection) override;
  void OnCharTyped(base::TimeTicks timestamp) override;
  void OnMatchIconUpdated(size_t index) override {}
  void OnContentsChanged() override {}

  // TabListInterfaceObserver:
  void OnActiveTabChanged(TabListInterface& tab_list,
                          tabs::TabInterface* tab) override;

 private:
  // When the omnibox is hosted in a tab, e.g. for debug, it must remain
  // connected with the host window's OmniboxController. These methods
  // support disconnect and reconnect as the window changes to avoid UAF.
  void OnTabWillDetach(tabs::TabInterface* tab,
                       tabs::TabInterface::DetachReason reason);
  void OnTabDidInsert(tabs::TabInterface* tab);

  void UpdateAimButtonVisibility();

  // Delegate to observe WebContents.
  // Managed as a separate class to prevent member naming conflicts
  // of `web_contents_` with a member of the same name in `SearchboxHandler`.
  class WebContentsObserver : public content::WebContentsObserver {
   public:
    explicit WebContentsObserver(WebuiOmniboxHandler* handler,
                                 content::WebContents* web_contents);

    void ScopedObserve(content::WebContents* web_contents);

    void DidFinishNavigation(content::NavigationHandle* handle) override;

   private:
    raw_ptr<WebuiOmniboxHandler> handler_;
  };

  // ContextualSearchboxHandler:
  int GetContextMenuMaxTabSuggestions() override;

  void OnContentSharingPolicyChanged();
  void OnAimPopupEligibilityChanged();
  void OnAiModeButtonConfigChanged(const AiModeButtonUiConfig* config);
  void OnNavigationFinished(content::NavigationHandle* navigation_handle);

  WebContentsObserver web_contents_observer_;

  // Observe `OmniboxEditModel` for updates that require updating the views.
  base::ScopedObservation<OmniboxEditModel, OmniboxEditModel::Observer>
      edit_model_observation_{this};

  PrefChangeRegistrar pref_change_registrar_;
  base::CallbackListSubscription aim_eligibility_subscription_;
  base::CallbackListSubscription ai_mode_config_subscription_;
  base::CallbackListSubscription tab_will_detach_subscription_;
  base::CallbackListSubscription tab_did_insert_subscription_;

  raw_ptr<MetricsReporter> metrics_reporter_;

  base::WeakPtrFactory<WebuiOmniboxHandler> weak_ptr_factory_{this};
};

#endif  // CHROME_BROWSER_UI_WEBUI_SEARCHBOX_WEBUI_OMNIBOX_HANDLER_H_