//  Linux_Lab_42
//
//  Created by Sergiy on 04.02.17.

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <string.h>
#include <time.h>
#include <unistd.h>


char * mailHeader(const char* from, const char* to, const char* subject, const char* mime_type, const char* charset);
int connectToServer(const char* serverAddress);
int createTCPsocket();
char *getIP(char* targetDomain);


int main(int argc, const char * argv[])
{
    const char* from;
    const char* to;
    char *header;
    int sock;
    char *ip;
    //char* targetDomain = "smtp.ukr.net";
    //char* targetDomain = "aspmx.l.google.com";
    char* targetDomain = "ASPMX.L.GOOGLE.com";
    struct sockaddr_in *server;
    int port = 25;
    //int port = 465;
    int tmpres;
    int connected_fd;
    int recvd;
    char recv_buf[3000];
    ssize_t receivingResult; //length of the message on successful completion of receiving messages from a socket
    ssize_t sendingResult; //the number of bytes sent
    char buff[1000];
    char _cmd2[1000];


    // get mail header -START-

    //from = "lab42linux@ukr.net";
    from = "sergiy.osadchyy@gmail.com";
    to = "sergiy.osadchyy@gmail.com";
    header = mailHeader(from, to, "Hello, it's a test mail", "text/plain", "US-ASCII");
    printf("The mail header is \n%s\n", header);

    // get mail header -END-

    //-------------

    // Create socket -START-

    sock = createTCPsocket();
    //printf("File descriptor that refers to endpoint is %d\n\n", sock);

    // Create socket -END-

    //-----------

    // Get IP -START-

    ip = getIP(targetDomain);

    fprintf(stderr, "IP is %s\n", ip);

    // Get IP -END-

    //---------

    // Setup server -START-

    server = (struct sockaddr_in *)malloc(sizeof(struct sockaddr_in *)) ;

    server->sin_family = AF_INET;
    server->sin_port = htons(port);

    tmpres = inet_pton(AF_INET, ip, (void *)(&(server->sin_addr.s_addr)));

    if (tmpres < 0)
    {
        perror("Can't set remote->sin_addr.s_addr");
        exit(1);
    }
    else if (tmpres == 0)
    {
        fprintf("%s is not a valid IP address\n", ip);
        exit(1);
    }

    // Setup server -END-

    //-----------

    // Connect -START-

    connected_fd = connect(sock, (struct sockaddr *)server, sizeof(struct sockaddr));
    if (connected_fd == -1)
    {
        perror("Could not connect");
        exit(1);
    }
    printf("\nThe value of connected fd is %d\n", connected_fd);
    // Connect -END-

    //-------------


    recvd = 0;
    receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
    recvd += receivingResult;

    printf("\nThe value of receivingResult is %zd\n", receivingResult);
    printf("\nThe value of recvd is %d\n", recvd);


    strcpy(buff, "EHLO ");
    strcat(buff, targetDomain);
    strcat(buff, "\r\n");
    sendingResult = send(connected_fd, buff, strlen(buff), 0);
    receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
    recvd += receivingResult;

    printf("The value of buff is %s\n", buff);
    printf("\nThe value of sendingResult is %zd\n", sendingResult);
    printf("\nThe value of receivingResult is %zd\n", receivingResult);
    printf("\nThe value of recvd is %d\n", recvd);

    strcpy(_cmd2, "AUTH LOGIN\r\n");
    sendingResult = send(connected_fd, _cmd2, strlen(_cmd2), 0);
    receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
    recvd += receivingResult;




    /*

        char _cmd3[1000];
        Base64encode(&_cmd3, UID, strlen(UID));
        strcat(_cmd3, "\r\n");
        send(connected_fd, _cmd3, strlen(_cmd3), 0);
        receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
        recvd += receivingResult;

        char _cmd4[1000];
        Base64encode(&_cmd4, PWD, strlen(PWD));
        strcat(_cmd4, "\r\n");
        send(connected_fd, _cmd4, strlen(_cmd4), 0);
        receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
        recvd += receivingResult;

        char _cmd5[1000];
        strcpy(_cmd5, "MAIL FROM: ");
        strcat(_cmd5, "<lab42linux@ukr.net>");
        strcat(_cmd5, "\r\n");
        send(connected_fd, _cmd5, strlen(_cmd5), 0);
        char skip[1000];
        receivingResult = recv(connected_fd, skip, sizeof(skip), 0);
        //recvd += receivingResult;

        char _cmd6[1000];
        strcpy(_cmd6, "RCPT TO: ");
        strcat(_cmd6, "sergiy.osadchyy@gmail.com");
        strcat(_cmd6, "\r\n");
        send(connected_fd, _cmd6, strlen(_cmd6), 0);
        receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
        recvd += receivingResult;

        char _cmd7[1000];
        strcpy(_cmd7, "DATA\r\n");
        send(connected_fd, _cmd7, strlen(_cmd7), 0);
        receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
        recvd += receivingResult;

        send(connected_fd, header, strlen(header), 0);

        char _cmd8[1000];
        strcpy(_cmd8, "Hello, I am testing my smtp app");
        send(connected_fd, _cmd8, strlen(_cmd8), 0);

        char _cmd9[1000];
        strcpy(_cmd9, "\r\n.\r\n.");
        send(connected_fd, _cmd9, strlen(_cmd9), 0);
        receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
        recvd += receivingResult;

        char _cmd10[1000];
        strcpy(_cmd10, "QUIT\r\n");
        send(connected_fd, _cmd10, strlen(_cmd10), 0);
        receivingResult = recv(connected_fd, recv_buf + recvd, sizeof(recv_buf) - recvd, 0);
        recvd += receivingResult;

        printf("0)%s\r\n", &recv_buf);


    free(header);
    close(connected_fd);

*/

    return (EXIT_SUCCESS);
}


char * mailHeader(const char* from, const char* to, const char* subject, const char* mime_type, const char* charset)
{
    time_t now;
    time(&now);
    char *app_brand = "My lab42 mail APP";
    char* mail_header = NULL;
    char date_buff[26];
    char branding[6 + strlen(date_buff) + 2 + 10 + strlen(app_brand) + 1 + 1];
    char sender[6 + strlen(from) + 1 + 1];
    char recip[4 + strlen(to) + 1 + 1];
    char mySubject[8 + 1 + strlen(subject) + 1 + 1];
    //char mime_data[13 + 1 + 3 + 1 + 1 + 13 + 1 + strlen(mime_type) + 1 + 1 + 2];
    char *mime_data[13 + 1 + 3 + 1 + 1 + 13 + 1 + strlen(mime_type) + 1 + 1 + 2];

    strftime(date_buff, (33), "%a, %d %b %Y %H:%M:%S", localtime(&now));

    sprintf(branding, "DATE: %s\r\nX-Mailer: %s\r\n", date_buff, app_brand);
    sprintf(sender, "FROM: %s\r\n", from);
    sprintf(recip, "TO: %s\r\n", to);
    sprintf(mySubject, "SUBJECT: %s\r\n", subject);
    sprintf(mime_data, "MIME-version: 1.0\r\nContent-type: %s; charset=%s\r\n\r\n", mime_type, charset);

    int mail_header_length = strlen(branding) + strlen(sender) + strlen(recip) + strlen(mySubject) + strlen(mime_data) + 10;

    mail_header = (char*) malloc(mail_header_length * sizeof(char));
    memset(mail_header, 0, mail_header_length * sizeof(char));

    memcpy(&mail_header[0], &branding, strlen(branding));
    memcpy(&mail_header[0 + strlen(branding)], &sender, strlen(sender));
    memcpy(&mail_header[0 + strlen(branding) + strlen(sender)], &recip, strlen(recip));
    memcpy(&mail_header[0 + strlen(branding) + strlen(sender) + strlen(recip)], &mySubject, strlen(mySubject));
    memcpy(&mail_header[0 + strlen(branding) + strlen(sender) + strlen(recip) + strlen(mySubject)], &mime_data, strlen(mime_data));

    return mail_header;
}


int createTCPsocket()
{
    int sock;

    sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

    if (sock < 0 )
    {
        perror("Failed to create socket\n");
        exit(1);
    }

    return sock;
}

char *getIP(char* targetDomain)
{
    struct hostent *hent;

    int iplen = 15; //XXX.XXX.XXX.XXX

    char *ip = (char *)malloc(iplen + 1);
    memset(ip, 0, iplen+1);

    if ((hent = gethostbyname(targetDomain)) == NULL)
    {
        perror("Can't get IP\n");
        exit(1);
    }

    if ((inet_ntop(AF_INET, (void *)hent->h_addr_list[0], ip, iplen)) == NULL)
    {
        perror("\nCan't resolve host\n");
        printf("\n");
        exit(1);
    }

    return ip;
}