/*
 *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef RTC_BASE_SOCKET_ADDRESS_H_
#define RTC_BASE_SOCKET_ADDRESS_H_

#include <string>

#include "absl/strings/string_view.h"
#include "rtc_base/ip_address.h"
#include "rtc_base/system/rtc_export.h"

#undef SetPort

struct sockaddr_in;
struct sockaddr_storage;

namespace rtc {

// Records an IP address and port.
class RTC_EXPORT SocketAddress {
 public:
  // Creates a nil address.
  SocketAddress();

  // Creates the address with the given host and port. Host may be a
  // literal IP string or a hostname to be resolved later.
  // DCHECKs that port is in valid range (0 to 2^16-1).
  SocketAddress(absl::string_view hostname, int port);

  // Creates the address with the given IP and port.
  // IP is given as an integer in host byte order. V4 only, to be deprecated.
  // DCHECKs that port is in valid range (0 to 2^16-1).
  SocketAddress(uint32_t ip_as_host_order_integer, int port);

  // Creates the address with the given IP and port.
  // DCHECKs that port is in valid range (0 to 2^16-1).
  SocketAddress(const IPAddress& ip, int port);

  // Creates a copy of the given address.
  SocketAddress(const SocketAddress& addr);

  // Resets to the nil address.
  void Clear();

  // Determines if this is a nil address (empty hostname, any IP, null port)
  bool IsNil() const;

  // Returns true if ip and port are set.
  bool IsComplete() const;

  // Replaces our address with the given one.
  SocketAddress& operator=(const SocketAddress& addr);

  // Changes the IP of this address to the given one, and clears the hostname
  // IP is given as an integer in host byte order. V4 only, to be deprecated..
  void SetIP(uint32_t ip_as_host_order_integer);

  // Changes the IP of this address to the given one, and clears the hostname.
  void SetIP(const IPAddress& ip);

  // Changes the hostname of this address to the given one.
  // Does not resolve the address; use Resolve to do so.
  void SetIP(absl::string_view hostname);

  // Sets the IP address while retaining the hostname.  Useful for bypassing
  // DNS for a pre-resolved IP.
  // IP is given as an integer in host byte order. V4 only, to be deprecated.
  void SetResolvedIP(uint32_t ip_as_host_order_integer);

  // Sets the IP address while retaining the hostname.  Useful for bypassing
  // DNS for a pre-resolved IP.
  void SetResolvedIP(const IPAddress& ip);

  // Changes the port of this address to the given one.
  // DCHECKs that port is in valid range (0 to 2^16-1).
  void SetPort(int port);

  // Returns the hostname.
  const std::string& hostname() const { return hostname_; }

  // Returns the IP address as a host byte order integer.
  // Returns 0 for non-v4 addresses.
  uint32_t ip() const;

  const IPAddress& ipaddr() const;

  int family() const { return ip_.family(); }

  // Returns the port part of this address.
  uint16_t port() const;

  // Returns the scope ID associated with this address. Scope IDs are a
  // necessary addition to IPv6 link-local addresses, with different network
  // interfaces having different scope-ids for their link-local addresses.
  // IPv4 address do not have scope_ids and sockaddr_in structures do not have
  // a field for them.
  int scope_id() const { return scope_id_; }
  void SetScopeID(int id) { scope_id_ = id; }

  // Returns the 'host' portion of the address (hostname or IP) in a form
  // suitable for use in a URI. If both IP and hostname are present, hostname
  // is preferred. IPv6 addresses are enclosed in square brackets ('[' and ']').
  std::string HostAsURIString() const;

  // Same as HostAsURIString but anonymizes IP addresses by hiding the last
  // part.
  std::string HostAsSensitiveURIString() const;

  // Returns the port as a string.
  std::string PortAsString() const;

  // Returns hostname:port or [hostname]:port.
  std::string ToString() const;

  // Same as ToString but anonymizes it by hiding the last part.
  std::string ToSensitiveString() const;

  // Returns sensitive description of address in a form which both includes
  // resolved and unresolved addresses based on their availability.
  std::string ToSensitiveNameAndAddressString() const;

  // Parses hostname:port and [hostname]:port.
  bool FromString(absl::string_view str);

  // Determines whether this represents a missing / any IP address.
  // That is, 0.0.0.0 or ::.
  // Hostname and/or port may be set.
  bool IsAnyIP() const;

  // Determines whether the IP address refers to a loopback address.
  // For v4 addresses this means the address is in the range 127.0.0.0/8.
  // For v6 addresses this means the address is ::1.
  bool IsLoopbackIP() const;

  // Determines whether the IP address is in one of the private ranges:
  // For v4: 127.0.0.0/8 10.0.0.0/8 192.168.0.0/16 172.16.0.0/12.
  // For v6: FE80::/16 and ::1.
  bool IsPrivateIP() const;

  // Determines whether the hostname has been resolved to an IP.
  bool IsUnresolvedIP() const;

  // Determines whether this address is identical to the given one.
  bool operator==(const SocketAddress& addr) const;
  inline bool operator!=(const SocketAddress& addr) const {
    return !this->operator==(addr);
  }

  // Compares based on IP and then port.
  bool operator<(const SocketAddress& addr) const;

  // Determines whether this address has the same IP as the one given.
  bool EqualIPs(const SocketAddress& addr) const;

  // Determines whether this address has the same port as the one given.
  bool EqualPorts(const SocketAddress& addr) const;

  // Hashes this address into a small number.
  size_t Hash() const;

  // Write this address to a sockaddr_in.
  // If IPv6, will zero out the sockaddr_in and sets family to AF_UNSPEC.
  void ToSockAddr(sockaddr_in* saddr) const;

  // Read this address from a sockaddr_in.
  bool FromSockAddr(const sockaddr_in& saddr);

  // Read and write the address to/from a sockaddr_storage.
  // Dual stack version always sets family to AF_INET6, and maps v4 addresses.
  // The other version doesn't map, and outputs an AF_INET address for
  // v4 or mapped addresses, and AF_INET6 addresses for others.
  // Returns the size of the sockaddr_in or sockaddr_in6 structure that is
  // written to the sockaddr_storage, or zero on failure.
  size_t ToDualStackSockAddrStorage(sockaddr_storage* saddr) const;
  size_t ToSockAddrStorage(sockaddr_storage* saddr) const;

 private:
  std::string hostname_;
  IPAddress ip_;
  uint16_t port_;
  int scope_id_;
  bool literal_;  // Indicates that 'hostname_' contains a literal IP string.
};

RTC_EXPORT bool SocketAddressFromSockAddrStorage(const sockaddr_storage& saddr,
                                                 SocketAddress* out);
SocketAddress EmptySocketAddressWithFamily(int family);

}  // namespace rtc

#endif  // RTC_BASE_SOCKET_ADDRESS_H_