/*----------------------------------------------------------------------------*/
/* Copyright (c) 2011-2017 FIRST. All Rights Reserved.                        */
/* Open Source Software - may be modified and shared by FRC teams. The code   */
/* must be accompanied by the FIRST BSD license file in the root directory of */
/* the project.                                                               */
/*----------------------------------------------------------------------------*/

#pragma once

#include <memory>
#include <string>

#include <llvm/StringMap.h>
#include <llvm/StringRef.h>

#include "SmartDashboard/SendableChooserBase.h"
#include "networktables/NetworkTable.h"
#include "networktables/NetworkTableEntry.h"

namespace frc {

/**
 * The SendableChooser class is a useful tool for presenting a selection of
 * options to the SmartDashboard.
 *
 * For instance, you may wish to be able to select between multiple autonomous
 * modes. You can do this by putting every possible Command you want to run as
 * an autonomous into a SendableChooser and then put it into the SmartDashboard
 * to have a list of options appear on the laptop. Once autonomous starts,
 * simply ask the SendableChooser what the selected value is.
 *
 * @tparam T The type of values to be stored
 * @see SmartDashboard
 */
template <class T>
class SendableChooser : public SendableChooserBase {
  llvm::StringMap<T> m_choices;
  nt::NetworkTableEntry m_selectedEntry;

  template <class U>
  static U _unwrap_smart_ptr(const U& value);

  template <class U>
  static U* _unwrap_smart_ptr(const std::unique_ptr<U>& value);

  template <class U>
  static std::weak_ptr<U> _unwrap_smart_ptr(const std::shared_ptr<U>& value);

 public:
  virtual ~SendableChooser() = default;

  void AddObject(llvm::StringRef name, T object);
  void AddDefault(llvm::StringRef name, T object);

  auto GetSelected() -> decltype(_unwrap_smart_ptr(m_choices[""]));

  void InitTable(std::shared_ptr<nt::NetworkTable> subtable) override;
};

}  // namespace frc

#include "SendableChooser.inc"