#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sqlite3.h>
/* portul folosit */
#define PORT 2099
/* codul de eroare returnat de anumite apeluri */
extern int errno;

static int call(void *data,int argc, char **argv, char **azColName)
{
	if (argv==NULL)
		 return 0;
	else
		 return 4;
}
int makeUserOnline(char userName[30])
{
    sqlite3 *db;
    char *zErrMsg = 0;
    int rc;
    char *sql;
    rc = sqlite3_open("data.db", &db);
    sql=(char*)malloc(100);
    bzero(sql,100);
    strcpy(sql,"INSERT into online_users (username) values('");
    strcat(sql,userName);
    strcat(sql,"')");
   rc = sqlite3_exec(db, sql, call, NULL, &zErrMsg);
   if( rc != SQLITE_OK && rc!=4)
   {
      fprintf(stderr, "SQL error: %s\n", zErrMsg);
      sqlite3_free(zErrMsg);
    }
    else
    {
      fprintf(stdout, "Adaugat la lista utilizatorilor conectati \n");
    }

    return rc;

  }

int makeUserOffline(char userName[30])
{
   sqlite3 *db;
    char *zErrMsg = 0;
    int rc;
    char *sql;
    rc = sqlite3_open("data.db", &db);
    sql=(char*)malloc(100);
    bzero(sql,100);
     strcpy(sql,"DELETE from online_users WHERE username='");
    strcat(sql,userName);
    strcat(sql,"'");
   rc = sqlite3_exec(db, sql, call, NULL, &zErrMsg);
   if( rc != SQLITE_OK && rc!=4)
   {
      fprintf(stderr, "SQL error: %s\n", zErrMsg);
      sqlite3_free(zErrMsg);
    }
    else
    {
      fprintf(stdout, "Adaugat la lista utilizatorilor deconectati \n");
    }

    return rc;
}

void querryAnswer(int rc, char answer[100],char*zErrMsg)
{
   if( rc != SQLITE_OK && rc!=4)
     {
       fprintf(stderr, "SQL error: %s\n", zErrMsg);
       sqlite3_free(zErrMsg);
     }
     else
     {
       fprintf(stdout,"%s\n", answer);
     }

}

void selectOption(int client,int optiune)
{
  if (read (client, &optiune,sizeof(optiune)) <= 0)
	{
	  perror ("[server]Eroare la read() de la client.\n");
	  //close (client);	/* inchidem conexiunea cu clientul */
  }

   // Pregatim structurile si descriptorii pentru a accesa baza de date
   sqlite3 *db;
   char *zErrMsg = 0;
   int rc;
   char *sql;
   rc = sqlite3_open("data.db", &db);
   if( rc )
   {
      fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db));
      exit(-1);
   }
  else
   {
      fprintf(stderr, "Opened database successfully\n");
    }



  char userName[30];
  char password[30];
  char answer[150];
  int online_status;
  switch(optiune)
  {
    case 1:  // LOGIN
     if (read (client, userName, 30) <= 0)
   	  {
	      perror ("[server]Eroare la read() de la client.\n");
	      close (client);
      }

     if (read (client, password, 30) <= 0)
    	{
	       perror ("[server]Eroare la read() de la client.\n");
	       close (client);
      }

     /// Verificam daca ii gasim in baza de date
     sql=(char*)malloc(100);
     bzero(sql,100);
     strcat(sql,"SELECT * from USERS WHERE userName='");
     strcat(sql,userName);
     strcat(sql,"' AND password='");
     strcat(sql,password);
     strcat(sql,"'");

     rc = sqlite3_exec(db, sql, call, NULL, &zErrMsg);
     querryAnswer(rc,"S-a logat un utilizator!",zErrMsg);

    if(rc ==4 ) //USER LOGAT CU SUCCES
     {
       int online_status=makeUserOnline(userName);
       bzero(answer,150);
       strcat(answer,"Te-ai logat cu succes!\nDoriti sa consultati meniul?");
       if (write (client,answer,150) <= 0)
       {
			      perror ("[client]Eroare la write() spre server.\n");
			      exit(-1);
       }

      /// Clientul alege daca sa folosesca meniul sau nu
      int meniu_accesat;
      if (read (client, &meniu_accesat,sizeof(meniu_accesat)) <= 0)
    	{
	       perror ("[server]Eroare la read() de la client.\n");
	       close (client);
      }

      if(meniu_accesat == 0)
      {
        printf("Un client a ales deconectarea \n");
        online_status=makeUserOffline(userName);
        close(client);
      }

      else
      {
        printf("Meniul a fost accesat ! \n");
      }



     }
    else  if(rc ==0)
    {
        bzero(answer,50);
        strcat(answer,"Nu exista un user cu acest nume/parola!\n");
        if (write (client,answer,50) <= 0)
          {
			      perror ("[client]Eroare la write() spre server.\n");
            exit(-1);
          }
          close(client);
    }

    //Trebuie sa trimit mesajele primite
    // Aici o sa primesc comenzile pt celalat meniu
    break;

    case 2: // INREGISTRARE

       if (read (client, userName, 30) <= 0)
   	  {
	      perror ("[server]Eroare la read() de la client.\n");
	      close (client);
      }

      if (read (client, password, 30) <= 0)
    	{
         perror ("[server]Eroare la read() de la client.\n");
	       close (client);
      }

     // Verific daca user-ul este deja folosit
     sql=(char*)malloc(100);
     bzero(sql,100);
     strcat(sql,"SELECT * from USERS WHERE userName='");
     strcat(sql,userName);
     strcat(sql,"'");

     rc = sqlite3_exec(db, sql, call, NULL, &zErrMsg);
     querryAnswer(rc,"Operation done successfully!",zErrMsg);


     if(rc ==4)
     {
       bzero(answer,50);
       strcat(answer,"Exista un alt user cu acest nume!\n");
       if (write (client,answer,50) <= 0)
          {
			      perror ("[client]Eroare la write() spre server.\n");
			      exit(-1);
          }
     }

     else if(rc==0)
     {
        sql=(char*)malloc(100);
        bzero(sql,100);
        strcpy(sql,"INSERT into USERS(userName,password) values('");
				strcat(sql,userName);
				strcat(sql,"','");
				strcat(sql,password);
        strcat(sql,"')");

        int rc2;
        rc2 = sqlite3_exec(db, sql, call, NULL, &zErrMsg);
        if( rc2 != SQLITE_OK && rc2!=4)
       {
           fprintf(stderr, "SQL error: %s\n", zErrMsg);
           sqlite3_free(zErrMsg);
       }
       else
       {
          fprintf(stdout, "Am inregistrat un nou user !\n");
          bzero(answer,50);
          strcat(answer,"Ai fost inregistrat !\n");
          if (write (client,answer,50) <= 0)
          {
			      perror ("[client]Eroare la write() spre server.\n");
			      exit(-1);
          }

       }

     }

    break;
    case 3:
       printf("Un client a ales deconectarea \n");
       close(client);
       exit(-1);
       break;
    default:
       printf("Optiune introdusa gresit !\n");
       close(client);
       exit(-1);
       break;

  }
}

int main ()
{
  struct sockaddr_in server;
  struct sockaddr_in from;
  int sd;
  if ((sd = socket (AF_INET, SOCK_STREAM, 0)) == -1)
    {
      perror ("[server]Eroare la socket().\n");
      return errno;
    }
  bzero (&server, sizeof (server));
  bzero (&from, sizeof (from));
  server.sin_family = AF_INET;
  server.sin_addr.s_addr = htonl (INADDR_ANY);
  server.sin_port = htons (PORT);
  if (bind (sd, (struct sockaddr *) &server, sizeof (struct sockaddr)) == -1)
    {
      perror ("[server]Eroare la bind().\n");
      return errno;
    }
  if (listen (sd, 5) == -1)
    {
      perror ("[server]Eroare la listen().\n");
      return errno;
    }


  while (1)
    {
      int client;
      int length = sizeof (from);
      printf ("[server]Asteptam la portul %d...\n",PORT);
      fflush (stdout);
      client = accept (sd, (struct sockaddr *) &from, &length);
      if (client < 0)
	    {
	      perror ("[server]Eroare la accept().\n");
	      continue;
      }
      printf("%d\n",client);
      pid_t pd;
      pd = fork();

      if(pd == 0)
      {
        fflush (stdout);
        int optiune;
        selectOption(client,optiune);
      }

    }
}