// Copyright 2018 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.

#ifndef BASE_FUCHSIA_SERVICE_DIRECTORY_H_
#define BASE_FUCHSIA_SERVICE_DIRECTORY_H_

#include <lib/zx/channel.h>

#include "base/base_export.h"
#include "base/callback.h"
#include "base/containers/flat_map.h"
#include "base/macros.h"
#include "base/strings/string_piece.h"
#include "base/threading/thread_checker.h"

typedef struct svc_dir svc_dir_t;

namespace base {
namespace fuchsia {

// Directory of FIDL services published for other processes to consume. Services
// published in this directory can be discovered from other processes by name.
// Normally this class should be used by creating a ScopedServiceBinding
// instance. This ensures that the service is unregistered when the
// implementation is destroyed. GetDefault() should be used to get the default
// ServiceDirectory for the current process. The default instance exports
// services via a channel supplied at process creation time.
//
// Not thread-safe. All methods must be called on the thread that created the
// object.
class BASE_EXPORT ServiceDirectory {
 public:
  // Callback called to connect incoming requests.
  using ConnectServiceCallback =
      base::RepeatingCallback<void(zx::channel channel)>;

  // Creates services directory that will be served over the
  // |directory_channel|.
  explicit ServiceDirectory(zx::channel directory_channel);

  ~ServiceDirectory();

  // Returns default ServiceDirectory instance for the current process. It
  // publishes services to the directory provided by the process creator.
  static ServiceDirectory* GetDefault();

  void AddService(StringPiece name, ConnectServiceCallback connect_callback);
  void RemoveService(StringPiece name);
  void RemoveAllServices();

 private:
  // Called by |svc_dir_| to handle service requests.
  static void HandleConnectRequest(void* context,
                                   const char* service_name,
                                   zx_handle_t service_request);

  THREAD_CHECKER(thread_checker_);

  svc_dir_t* svc_dir_ = nullptr;
  base::flat_map<std::string, ConnectServiceCallback> services_;

  DISALLOW_COPY_AND_ASSIGN(ServiceDirectory);
};

}  // namespace fuchsia
}  // namespace base

#endif  // BASE_FUCHSIA_SERVICE_DIRECTORY_H_