// Copyright 2014 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_AUTOFILL_CONTENT_BROWSER_CONTENT_AUTOFILL_DRIVER_FACTORY_H_
#define COMPONENTS_AUTOFILL_CONTENT_BROWSER_CONTENT_AUTOFILL_DRIVER_FACTORY_H_

#include <string>
#include <vector>

#include "base/containers/flat_map.h"
#include "base/memory/raw_ref.h"
#include "base/observer_list.h"
#include "base/types/pass_key.h"
#include "components/autofill/content/common/mojom/autofill_driver.mojom.h"
#include "components/autofill/core/browser/foundations/autofill_driver_factory.h"
#include "components/autofill/core/browser/foundations/autofill_driver_router.h"
#include "content/public/browser/web_contents_observer.h"
#include "mojo/public/cpp/bindings/pending_associated_receiver.h"

namespace content {
class RenderFrameHost;
}

namespace autofill {

class ContentAutofillClient;
class ContentAutofillDriver;

// Creates one ContentAutofillDriver per content::RenderFrameHost and manages
// its lifecycle corresponding to the content::RenderFrameHost's lifecycle.
//
// Owned by ContentAutofillClient, therefore there is one
// ContentAutofillDriverFactory per content::WebContents.
class ContentAutofillDriverFactory : public AutofillDriverFactory,
                                     public content::WebContentsObserver {
 public:
  // A variant of AutofillDriverFactory::Observer with AutofillDriver[Factory]
  // narrowed to ContentAutofillDriver[Factory].
  // See AutofillDriverFactory::Observer for further documentation.
  class Observer : public AutofillDriverFactory::Observer {
   public:
    virtual void OnContentAutofillDriverFactoryDestroyed(
        ContentAutofillDriverFactory& factory) {}
    virtual void OnContentAutofillDriverCreated(
        ContentAutofillDriverFactory& factory,
        ContentAutofillDriver& driver) {}
    virtual void OnContentAutofillDriverStateChanged(
        ContentAutofillDriverFactory& factory,
        ContentAutofillDriver& driver,
        AutofillDriver::LifecycleState old_state,
        AutofillDriver::LifecycleState new_state) {}

    // AutofillDriverFactory::Observer:
    void OnAutofillDriverFactoryDestroyed(AutofillDriverFactory& factory) final;
    void OnAutofillDriverCreated(AutofillDriverFactory& factory,
                                 AutofillDriver& driver) final;
    void OnAutofillDriverStateChanged(AutofillDriverFactory& factory,
                                      AutofillDriver& driver,
                                      LifecycleState old_state,
                                      LifecycleState new_state) final;
  };

  static ContentAutofillDriverFactory* FromWebContents(
      content::WebContents* contents);

  static void BindAutofillDriver(
      content::RenderFrameHost* render_frame_host,
      mojo::PendingAssociatedReceiver<mojom::AutofillDriver> pending_receiver);

  ContentAutofillDriverFactory(content::WebContents* web_contents,
                               ContentAutofillClient* client);
  ContentAutofillDriverFactory(ContentAutofillDriverFactory&) = delete;
  ContentAutofillDriverFactory& operator=(ContentAutofillDriverFactory&) =
      delete;
  ~ContentAutofillDriverFactory() override;

  // content::WebContentsObserver:
  void RenderFrameDeleted(content::RenderFrameHost* render_frame_host) override;
  void RenderFrameHostStateChanged(
      content::RenderFrameHost* render_frame_host,
      content::RenderFrameHost::LifecycleState old_state,
      content::RenderFrameHost::LifecycleState new_state) override;
  void DidFinishNavigation(
      content::NavigationHandle* navigation_handle) override;

  ContentAutofillClient& client() { return *client_; }

  AutofillDriverRouter& router() { return router_; }

  std::vector<AutofillDriver*> GetExistingDrivers() override;

  ContentAutofillDriver* DriverForFrame(
      content::RenderFrameHost* render_frame_host,
      base::PassKey<ContentAutofillDriver>) {
    return DriverForFrame(render_frame_host);
  }

 private:
  friend class ContentAutofillDriverFactoryTestApi;

  // Gets the `ContentAutofillDriver` associated with `render_frame_host`.
  // If `render_frame_host` is currently being deleted, this may be nullptr.
  // `render_frame_host` must be owned by `web_contents()`.
  ContentAutofillDriver* DriverForFrame(
      content::RenderFrameHost* render_frame_host);

  // The owning AutofillClient.
  const raw_ref<ContentAutofillClient> client_;

  // Routes events between different ContentAutofillDrivers.
  // Must be destroyed after |driver_map_|'s elements.
  AutofillDriverRouter router_;

  // Owns the drivers. Drivers are created lazily in DriverForFrame() and
  // destroyed in RenderFrameDeleted(). They are added to the map on
  // construction and removed from the map on deletion.
  //
  // The map should be empty at destruction time because its elements are erased
  // in RenderFrameDeleted(). In case it is not empty, is must be destroyed
  // before `router_` because ~ContentAutofillDriver() may access `router_`.
  //
  // The map type must be so that `driver_map_.emplace()` does *not* invalidate
  // references. Otherwise, recursive DriverForFrame() calls are unsafe.
  std::map<content::RenderFrameHost*, std::unique_ptr<ContentAutofillDriver>>
      driver_map_;

  // The maximum number of coexisting drivers over the lifetime of this factory.
  // TODO: crbug.com/342132628 - Remove the counter and the metric.
  size_t max_drivers_ = 0;
};

}  // namespace autofill

#endif  // COMPONENTS_AUTOFILL_CONTENT_BROWSER_CONTENT_AUTOFILL_DRIVER_FACTORY_H_