/* Copyright (c) 2006-2020. The SimGrid Team. All rights reserved.          */

/* This program is free software; you can redistribute it and/or modify it
 * under the terms of the license (GNU LGPL) which comes with this package. */

#ifndef INCLUDE_SIMGRID_S4U_STORAGE_HPP_
#define INCLUDE_SIMGRID_S4U_STORAGE_HPP_

#include <simgrid/forward.h>
#include <simgrid/s4u/Io.hpp>
#include <xbt/Extendable.hpp>
#include <xbt/base.h>
#include <xbt/signal.hpp>

#include <map>
#include <string>
#include <unordered_map>

namespace simgrid {

extern template class XBT_PUBLIC xbt::Extendable<s4u::Storage>;

namespace s4u {

/** Storage represent the disk resources, usually associated to a given host
 *
 * By default, SimGrid does not keep track of the actual data being written but
 * only computes the time taken by the corresponding data movement.
 */

class XBT_PUBLIC Storage : public xbt::Extendable<Storage> {
  friend Engine;
  friend Io;
  friend kernel::resource::StorageImpl;

public:
  explicit Storage(const std::string& name, kernel::resource::StorageImpl* pimpl);

protected:
  virtual ~Storage() = default;

public:
  /** @brief Callback signal fired when a new Storage is created */
  static xbt::signal<void(Storage&)> on_creation;
  /** @brief Callback signal fired when a Storage is destroyed */
  static xbt::signal<void(Storage const&)> on_destruction;
  /** @brief Callback signal fired when a Storage's state changes */
  static xbt::signal<void(Storage const&)> on_state_change;

  /** Retrieve a Storage by its name. It must exist in the platform file */
  static Storage* by_name(const std::string& name);
  static Storage* by_name_or_null(const std::string& name);

  /** @brief Retrieves the name of that storage as a C++ string */
  std::string const& get_name() const { return name_; }
  /** @brief Retrieves the name of that storage as a C string */
  const char* get_cname() const { return name_.c_str(); }

  const char* get_type() const;
  Host* get_host() const { return attached_to_; };
  void set_host(Host* host) { attached_to_ = host; }

  const std::unordered_map<std::string, std::string>* get_properties() const;
  const char* get_property(const std::string& key) const;
  void set_property(const std::string&, const std::string& value);

  IoPtr io_init(sg_size_t size, s4u::Io::OpType type);

  IoPtr read_async(sg_size_t size);
  sg_size_t read(sg_size_t size);

  IoPtr write_async(sg_size_t size);
  sg_size_t write(sg_size_t size);
  kernel::resource::StorageImpl* get_impl() const { return pimpl_; }

private:
  Host* attached_to_ = nullptr;
  kernel::resource::StorageImpl* const pimpl_;
  std::string name_;
};

} // namespace s4u
} // namespace simgrid

#endif /* INCLUDE_SIMGRID_S4U_STORAGE_HPP_ */
