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void *handle_client(void *arg) {

    int new_socket = *((int *) arg);

    /* --------------------------------------------------------------------------------*/

    // Receive the client request using recv() system call

    char buffer[1024];
    int bytes_received = recv(new_socket, buffer, 1024, 0);
    if (bytes_received < 0) {
        printf("Error receiving client request\n");
        return NULL;
    }

    buffer[bytes_received] = '\0';

    // Close the socket

    char* message = malloc(2048*sizeof(char));
    
    message = handle_input(buffer);

    if ( message != NULL) {

        // Send the message to the client

         int bytes_sent = send(new_socket, message, strlen(message), 0);
         if (bytes_sent < 0) {
            printf("Error sending message to client\n");
        }

        close(new_socket);

            // Mutex lock to protect the critical section
            static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
            pthread_mutex_lock(&lock);

            // Access the shared resources
            FILE* file = fopen("server_records.txt", "a");

            if (file != NULL) {

                
                fprintf(file, "Client request: %s\nServer response: %s\n\n", buffer, message);
                
                fclose(file);
                
            } 

            pthread_mutex_unlock(&lock);
            

    } 
    
    
    return NULL;
}


char* handle_input(char* data) {
    int i = 1;
    int k = 0;
    char seat_type[50];
    char number_of_seats[50];

    while ( *data != ' ') {
        seat_type[k++] = *(data++);
    }
    seat_type[k] = '\0';

    data++; // Skip the ' ' character

    int p = 0;
    while (*data != '\n') {
        number_of_seats[p++] = *(data++);
    }
    number_of_seats[p] = '\0';

    char* msg = malloc(1024*sizeof(char));
    char* file_msg = malloc(1024 * sizeof(char));
    

    pthread_mutex_lock(&lock_file); // lock file access

    FILE* file = fopen("Seat_Availability.txt", "r+");
    FILE* new_file;

    if (file != NULL) {

            int found = 0;

            char line[500], avl_seats[50];

            while (fgets(line, sizeof(line), file) != NULL) {

                char* token = strtok(line, " ");

                if (strcmp(token, seat_type) == 0) {

                    token = strtok(NULL, " ");

                    strcpy(avl_seats, token);

                    found = 1;

                    break;
                }
            }

            if (found) {

                int required_seats = atoi(number_of_seats);

                int available_seats = atoi(avl_seats);

                int remaining_seats = 0;

                char seats_remain[50];

                if (required_seats > available_seats) {
                    
                    strcpy(msg,"Required Number of Seats Not Available");

                } else {

                    remaining_seats = available_seats - required_seats;

                    sprintf(seats_remain, "%d", remaining_seats);

                    fseek(file, -strlen(avl_seats), SEEK_CUR); // move the file pointer back to the start of the available seats value

                    fprintf(file, "%s", seats_remain); // overwrite the old value with the new one

                    fflush(file);

                    sprintf(msg, "%d Seats have been booked for type %s", required_seats, seat_type);

                    sprintf(file_msg, "FOR TYPE: %s\n%d Seats have been booked. %d Seats remaining\n\n", seat_type, required_seats, remaining_seats);

                    new_file = fopen("server_records.txt", "a");

                    if (new_file != NULL) {

                            fprintf(new_file, "%s", file_msg);
                            fclose(new_file);
                        
                    } 
                }
            } else {

                strcpy(msg,"Seat type not found!");
            }

        
    }

    
    fclose(file);
    fclose(new_file);

    pthread_mutex_unlock(&lock_file); // unlock file access

    return msg;
}