#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "header.h"
#include <signal.h>
#include <sys/msg.h>
#include <sys/ipc.h>
#include <errno.h>

int server_queue = -1;
int clients_pids_qID[CLIENTS_NUMBER][2]; // [client_number][0] <= pid
int clients_counter = 0;
int can_quit = 0;

int send_message(Message m, int client_number) {
    int status = msgsnd(clients_pids_qID[client_number][1], &m, SIZE_OF_MESSAGE_STRUCTURE, 0);
    if (status == -1)
        printf("Do klienta: %d nie udalo wyslac sie wiadomosci.\n", clients_pids_qID[client_number][0]);
    else
        printf("Wyslano wiadomosc do klienta: %d\n", clients_pids_qID[client_number][0]);
    return status;
}

int get_client_number(int c_pid){
    int i = 0;
    for (i = 0; i <CLIENTS_NUMBER; i++)
        if(clients_pids_qID[i][0] = c_pid)
            return i;
    return -1;
}

char * upper_case(char * s){
    int i;
    printf("%s", s);
    for (i = 0; s[i] != '\0'; i++)
        if(s[i] >= 'a' && s[i] <= 'z')
            s[i] += 'A' - 'a';
    printf("%s", s);
    return s;
}

char * get_time(){
    time_t rt;
    struct tm * c_time;
    time (&rt);
    c_time = localtime(&rt);
    return asctime(c_time);
}

void sigint_handler(int sig_num){
    printf(" Otrzymalem SIGINT i zamykam serwer.\n");
    int i;
    for(i=0; i<CLIENTS_NUMBER; i++)
        if(clients_pids_qID[i][0] != -1)
            kill(clients_pids_qID[i][0], SIGINT);
    exit(0);
}

void server_closing(){
    if(server_queue != -1)
        if( msgctl(server_queue, IPC_RMID, NULL) == -1)
            printf("Wystapil problem z zamykaniem kolejki.\n");
        else
            printf("Kolejka zamknieta poprawnie. Serwer zakonczyl prace.\n");
    else
        printf("Serwer zakonczyl prace. Kolejka nie istanila.\n");
}

void init_client(Message message){
    if( clients_counter < CLIENTS_NUMBER - 1) {
        key_t client_key = atoi(message.mes);
        clients_pids_qID[clients_counter][0] = message.pid;

        if ((clients_pids_qID[clients_counter][1] = msgget(client_key, 0)) == -1) {
            printf("Nie udalo otorzyc sie kolejki klienta: %d z powodu: %s!\n", message.pid, strerror(errno));
            return;
        } else
            printf("Udalo otorzyc sie kolejke klienta %d\n", message.pid);
        clients_counter++;
    }
    else {
        printf("Osiagnieto maksymalna liczbe klientow!");
        kill(message.pid, SIGINT);
    }
}

int main(int argc, char** argv) {
    atexit(server_closing);
    signal(SIGINT, sigint_handler);

    int i,j;
    for(i=0; i<CLIENTS_NUMBER; i++)
        for(j=0; j<2; j++)
            clients_pids_qID[i][j] = -1;

    if ((server_queue = msgget(ftok(getenv("HOME"), 's'), IPC_CREAT | 0600)) == -1) {
        printf("Nie udalo utprzyc sie koljeki dla serwera!\n");
        exit(1);
    } else
        printf("Stworzono kolejke dla serwera %d\n",server_queue);

    struct msqid_ds q_state;
    while(1){
        if(can_quit == 1){
            if(msgctl(server_queue, IPC_STAT, &q_state) == -1)
                printf("Problem z pobieraniem statusu kolejki!\n");
            if(q_state.msg_qnum == 0)
                break;
        }
        Message m;
        int c_number = -1;
        printf("Odbieram.\n");
        if (msgrcv(server_queue, &m, SIZE_OF_MESSAGE_STRUCTURE, 0, 0) != -1) {
            switch (m.mtype) {
                case INIT_CLIENT:
                    init_client(m);
                    break;

                case ECHO:
                    c_number = get_client_number(m.pid);
                    if(c_number != -1){
                        send_message(m,c_number);
                    } else {
                        printf("Nie ma klienta o numerze %d \n",m.pid);
                    }
                    break;

                case UP:
                    c_number = get_client_number(m.pid);
                    if(c_number != -1){
                        upper_case(m.mes);
                        send_message(m,c_number);
                    } else {
                        printf("Nie ma klienta o numerze %d \n",m.pid);
                    }
                    break;

                case TIME:
                    c_number = get_client_number(m.pid);
                    if(c_number != -1){
                        strcpy(m.mes, get_time());
                        send_message(m,c_number);
                    } else {
                        printf("Nie ma klienta o numerze %d \n",m.pid);
                    }
                    break;

                case END:
                    printf("Wylaczanie serwera.\n");
                    can_quit = 1;
                    break;

                default:
                    printf("Nie ma takiego typu wiadomosci.\n");
                    break;
            }
        }
        else {
            //printf("Wystapil problem z otrzymywaniem wiadomosci.\n");
            continue;
        }
    }
    return 0;
}