/* Handles communication with a client. */

#pragma once

#include <common.h>
#include <netinet/in.h>

#define USERNAME_LEN 32

typedef struct
{
	int socket;						 /* client socket */
	struct sockaddr_in address;		 /* client address information */
	char ip_string[INET_ADDRSTRLEN]; /* client IP address as a string */
	time_t last_active;				 /* time of client's last activity */
	char username[USERNAME_LEN];	 /* username for human identification */
	char data[BUFFER_LEN];			 /* buffer for received data */
} client_t;

/**
 * Closes a client connection.
 */
void client_close(client_t *client);

/**
 * Reads data from a client into the client data buffer.
 * Also updates the timestamp of the client's last activity.
 *
 * Returns:
 * - number of read bytes on success,
 * - negative ENODATA value (-ENODATA) if the client has disconnected,
 * - negative errno value set by an error while reading
 */
int client_read(client_t *client);

/**
 * Sends data from a buffer to the client.
 *
 * Returns:
 * - number of sent bytes on success,
 * - negative errno value set by an error while sending
 */
int client_write(client_t *client, char *databuf, int datalen);

/**
 * Waits for input from the client in "line mode" (client sends a whole line of
 * characters). The function blocks until input arrives.
 *
 * Returns:
 * - 0 on success
 * - negative value if an error occurred
 */
int client_wait_line(client_t *client);

/**
 * Asks the client to provide a username.
 * Blocks until a string is provided.
 *
 * Returns:
 * - 0 on success
 * - negative value if an error occurred
 */
int client_ask_username(client_t *client);