/** Get the local IP address
 *
 *  @return         Null-terminated representation of the local IP address
 *                  or null if not yet connected
 */
const char *get_ip_address();

/** Get the local MAC address
 *
 *  @return         Null-terminated representation of the local MAC address
 */
const char *get_mac_address();

/** Opens a socket
 *
 *  Creates a network socket and stores it in the specified handle.
 *  The handle must be passed to following calls on the socket.
 *
 *  A stack may have a finite number of sockets, in this case
 *  NSAPI_ERROR_NO_SOCKET is returned if no socket is available.
 *
 *  @param handle   Destination for the handle to a newly created socket
 *  @param proto    Protocol of socket to open, NSAPI_TCP or NSAPI_UDP
 *  @return         0 on success, negative error code on failure
 */
int socket_open(void **handle, nsapi_protocol_t proto);

/** Close the socket
 *
 *  Closes any open connection and deallocates any memory associated
 *  with the socket.
 *
 *  @param handle   Socket handle
 *  @return         0 on success, negative error code on failure
 */
int socket_close(void *handle);

/** Bind a specific address to a socket
 *
 *  Binding a socket specifies the address and port on which to receive
 *  data. If the IP address is zeroed, only the port is bound.
 *
 *  @param handle   Socket handle
 *  @param address  Local address to bind
 *  @return         0 on success, negative error code on failure.
 */
int socket_bind(void *handle, const SocketAddress &address);

/** Listen for connections on a TCP socket
 *
 *  Marks the socket as a passive socket that can be used to accept
 *  incoming connections.
 *
 *  @param handle   Socket handle
 *  @param backlog  Number of pending connections that can be queued
 *                  simultaneously
 *  @return         0 on success, negative error code on failure
 */
int socket_listen(void *handle, int backlog);

/** Connects TCP socket to a remote host
 *
 *  Initiates a connection to a remote server specified by the
 *  indicated address.
 *
 *  @param handle   Socket handle
 *  @param address  The SocketAddress of the remote host
 *  @return         0 on success, negative error code on failure
 */
int socket_connect(void *handle, const SocketAddress &address);

/** Accepts a connection on a TCP socket
 *
 *  The server socket must be bound and set to listen for connections.
 *  On a new connection, creates a network socket and stores it in the
 *  specified handle. The handle must be passed to following calls on
 *  the socket.
 *
 *  A stack may have a finite number of sockets, in this case
 *  NSAPI_ERROR_NO_SOCKET is returned if no socket is available.
 *
 *  This call is non-blocking. If accept would block,
 *  NSAPI_ERROR_WOULD_BLOCK is returned immediately.
 *
 *  @param handle   Destination for a handle to the newly created socket
 *  @param server   Socket handle to server to accept from
 *  @return         0 on success, negative error code on failure
 */
int socket_accept(void **handle, void *server);

/** Send data over a TCP socket
 *
 *  The socket must be connected to a remote host. Returns the number of
 *  bytes sent from the buffer.
 *
 *  This call is non-blocking. If send would block,
 *  NSAPI_ERROR_WOULD_BLOCK is returned immediately.
 *
 *  @param handle   Socket handle
 *  @param data     Buffer of data to send to the host
 *  @param size     Size of the buffer in bytes
 *  @return         Number of sent bytes on success, negative error
 *                  code on failure
 */
int socket_send(void *handle, const void *data, unsigned size);

/** Receive data over a TCP socket
 *
 *  The socket must be connected to a remote host. Returns the number of
 *  bytes received into the buffer.
 *
 *  This call is non-blocking. If recv would block,
 *  NSAPI_ERROR_WOULD_BLOCK is returned immediately.
 *
 *  @param handle   Socket handle
 *  @param data     Destination buffer for data received from the host
 *  @param size     Size of the buffer in bytes
 *  @return         Number of received bytes on success, negative error
 *                  code on failure
 */
int socket_recv(void *handle, void *data, unsigned size);

/** Send a packet over a UDP socket
 *
 *  Sends data to the specified address. Returns the number of bytes
 *  sent from the buffer.
 *
 *  This call is non-blocking. If sendto would block,
 *  NSAPI_ERROR_WOULD_BLOCK is returned immediately.
 *
 *  @param handle   Socket handle
 *  @param address  The SocketAddress of the remote host
 *  @param data     Buffer of data to send to the host
 *  @param size     Size of the buffer in bytes
 *  @return         Number of sent bytes on success, negative error
 *                  code on failure
 */
int socket_sendto(void *handle, const SocketAddress &address, const void *data, unsigned size);

/** Receive a packet over a UDP socket
 *
 *  Receives data and stores the source address in address if address
 *  is not NULL. Returns the number of bytes received into the buffer.
 *
 *  This call is non-blocking. If recvfrom would block,
 *  NSAPI_ERROR_WOULD_BLOCK is returned immediately.
 *
 *  @param handle   Socket handle
 *  @param address  Destination for the source address or NULL
 *  @param data     Destination buffer for data received from the host
 *  @param size     Size of the buffer in bytes
 *  @return         Number of received bytes on success, negative error
 *                  code on failure
 */
int socket_recvfrom(void *handle, SocketAddress *address, void *buffer, unsigned size);

/** Register a callback on state change of the socket
 *
 *  The specified callback will be called on state changes such as when
 *  the socket can recv/send/accept successfully and on when an error
 *  occurs. The callback may also be called spuriously without reason.
 *
 *  The callback may be called in an interrupt context and should not
 *  perform expensive operations such as recv/send calls.
 *
 *  @param handle   Socket handle
 *  @param callback Function to call on state change
 *  @param data     Argument to pass to callback
 */
void socket_attach(void *handle, void (*callback)(void *), void *data);

/** Enum of standardized error codes 
 *
 *  Valid error codes have negative values and may
 *  be returned by any network operation.
 *
 *  @enum nsapi_error_t
 */
enum nsapi_error_t {
    NSAPI_ERROR_WOULD_BLOCK   = -3001,     /*!< no data is not available but call is non-blocking */
    NSAPI_ERROR_UNSUPPORTED   = -3002,     /*!< unsupported configuration */
    NSAPI_ERROR_NO_CONNECTION = -3003,     /*!< not connected to a network */
    NSAPI_ERROR_NO_SOCKET     = -3004,     /*!< socket not available for use */
    NSAPI_ERROR_NO_ADDRESS    = -3005,     /*!< IP address is not known */
    NSAPI_ERROR_NO_MEMORY     = -3006,     /*!< memory resource not available */
    NSAPI_ERROR_DNS_FAILURE   = -3007,     /*!< DNS failed to complete successfully */
    NSAPI_ERROR_DHCP_FAILURE  = -3008,     /*!< DHCP failed to complete successfully */
    NSAPI_ERROR_AUTH_FAILURE  = -3009,     /*!< connection to access point failed */
    NSAPI_ERROR_DEVICE_ERROR  = -3010,     /*!< failure interfacing with the network processor */
};

// replace 0.0.0.0 with the ip address of the host pc running the echo_server.py script
nsapi_tests("ESP8266Interface Tests", &iface, "0.0.0.0", 4000);