#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <string.h>
#include "assign1.h"


//feel free to include file headers you need that's not already in assign1.h

/**
 * Student Task 1: Fill in the infos below.
 */
char * get_student_name() {
    return "Chase_Delgadillo";
}
char * get_student_id() {
    //make sure it there is no trailing spaces
    return "891706806";
}
int get_class_section_number() {
    return 5;
}

/**
 * Student Task 2: implement socket server
 * Listen for TCP connection at loopback address 127.0.0.1
 * You must use the port defined by the macro: STUDENT_ANSWER_SOCKET_PORT
 * When the client connects, send the message string to the client.
 * You must perform proper cleanups such as closing sockets after the one client has been served.
 *
 * @param message the message to send when the client connects
 * @return 0 if success otherwise return non-zero
 */
int socket_server(char message[MAX_FILE_LENGTH]) {
    //TODO: implement
    int serversockfd, newsockfd;
    struct sockaddr_in serv_addr;
    struct sockaddr_storage serv_storage;
    socklen_t addr_size;

    /**Create socket
     * int socket(int domain, int type, int protocol)
     * domain   : protocol family used for communication [defined in <sys/socket.h>]
     *      AF_INET: Address Family, IPv4 Internet Protocols
     *      PF_INET: Protocol Family, IPv4 Internet Protocols
     * type     : specifies communication semantics
     *      SOCK_STREAM: provides sequenced, reliable, two-way, connection-based byte
     *      streams
     *          Must be connected (connect()) before data can be
     *          sent (send()) or received (recv())
     * protocol : specifies particular protocol to be used with socket
     *      Normally, only a single protocol exists to support a socket type
     *      within a given protocol family, in which case, set to 0
     */
    serversockfd = socket(PF_INET, SOCK_STREAM, 0);

    //Configure server address struct settings
    // family: required to be set to AF_INET: Address Family, IPv4 Internet Protocols
    serv_addr.sin_family = AF_INET;
    // port: STUDENT_ANSWER_SOCKET_PORT, based off definition in header
    //  htons() converts unsigned integer hostlong from host byte order to network byte order
    serv_addr.sin_port = htons(STUDENT_ANSWER_SOCKET_PORT);
    // ip address: TCP connection to loopback address
    serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    // Avoid bugs by padding buffer with sin_zero
    // Ref: https://silviocesare.wordpress.com/2007/10/22/setting-sin_zero-to-0-in-struct-sockaddr_in/
    memset(&serv_addr.sin_zero, 0, sizeof(serv_addr.sin_zero));

    /**Bind address/assigns a name to the socket
     *  By assigning a name to the socket,
     *  we cannot bind socket to the port twice for multiple tests
     * int bind(int sockfd, const struct sockaddr *addr, socklen_t addrlen)
     * sockfd  : socket to be assigned address
     * addr    : address to assign socket
     * addrlen : size of address structure, addr
     */
    if (bind(serversockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
        printf("ERROR binding...\n");

    /**Listen on socket, max connections requests in queue: 5
     * int listen(int sockfd, int backlog)
     * sockfd  : socket to be marked as passive socket
     * backlog : max length of pending connections for sockfd to queue
     */
    if (listen(serversockfd, 5) < 0)
        printf("ERROR listening...\n");

    /**Accept call creates new socket for incoming connection
     * int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
     * sockfd  : the created, bound, and listening socket
     * addr    : pointer to sockaddr structure filled with peer socket addresses
     * addrlen : size of sockaddr structure, addr
     */
    addr_size = sizeof(serv_storage);
    newsockfd = accept(serversockfd, (struct sockaddr *) &serv_storage, &addr_size);

    //Send message to socket of incoming connection
    strcpy(message, "Hello World\n");
    send(newsockfd, message, MAX_FILE_LENGTH, 0);

    close(newsockfd);
    close(serversockfd);
    return 0;
}

/**
 * Student Task 3: implement socket client
 * Make a TCP connection to loopback address 127.0.0.1
 * You must use the port defined by the macro: STUDENT_ANSWER_SOCKET_PORT
 *
 * Upon connection completion, read a message string from the server.
 * Close the connection and make sure the content of the message is
 * written or copied to the in parameter message
 * @return 0 if success otherwise return non-zero
 */
int socket_client(char message[MAX_FILE_LENGTH]) {
    //TODO: implement
    int clientsockfd;
    struct sockaddr_in serv_addr;
    socklen_t addr_size;

    /**Create socket
     * int socket(int domain, int type, int protocol)
     * domain   : protocol family used for communication [defined in <sys/socket.h>]
     *      AF_INET: Address Family, IPv4 Internet Protocols
     *      PF_INET: Protocol Family, IPv4 Internet Protocols
     * type     : specifies communication semantics
     *      SOCK_STREAM: provides sequenced, reliable, two-way, connection-based byte
     *      streams
     *          Must be connected (connect()) before data can be
     *          sent (send()) or received (recv())
     * protocol : specifies particular protocol to be used with socket
     *      Normally, only a single protocol exists to support a socket type
     *      within a given protocol family, in which case, set to 0
     */
    clientsockfd = socket(PF_INET, SOCK_STREAM, 0);


    //Configure server address struct settings
    // family: required to be set to AF_INET: Address Family, IPv4 Internet Protocols
    serv_addr.sin_family = AF_INET;
    // port: STUDENT_ANSWER_SOCKET_PORT, based off definition in header
    //  htons() converts unsigned integer hostlong from host byte order to network byte order
    serv_addr.sin_port = htons(STUDENT_ANSWER_SOCKET_PORT);
    // ip address: TCP connection to loopback address
    serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    // Avoid bugs by padding buffer with sin_zero
    // Ref: https://silviocesare.wordpress.com/2007/10/22/setting-sin_zero-to-0-in-struct-sockaddr_in/
    memset(&serv_addr.sin_zero, 0, sizeof(serv_addr.sin_zero));


    /**Connect socket to server
     * int connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen)
     * sockfd  : socket being connected
     * addr    : address we connect socket to
     * addrlen : size of address, addr
     */
    addr_size = sizeof(serv_addr);
    if (connect(clientsockfd, (struct sockaddr *) &serv_addr, addr_size) < 0)
        printf("ERROR connecting...\n");


    /**Read the message from the server into the message parameter given
     * ssize_t recv(int sockfd, void *buf, size_t len, int flags)
     * sockfd : connected socket receiving message
     * buf    : char buffer for recieved message
     * len    : size of char buffer, buf
     * flags  : message flags for info provided with recv() call
     *      Set to 0 due to lack of use, but to avoid zero-length datagram pending issue
     */
    recv(clientsockfd, message, MAX_FILE_LENGTH, 0);


    return 0;
}