/**
 *
 * @File : exo_07.cxx
 *
 * @Authors : A. B. Dragut
 *
 * @Date : 2011
 *
 *
 * @Synopsis : lectures/ecritures --- des acces concurrents
 *
 **/

#include <string>
#include <exception>
#include <cstdlib>          // atoi()

#include <unistd.h>         // sleep()
#include <fcntl.h>          // oflags de open()

#include <sys/stat.h>       // struct stat

#include "CExc.h"
#include "nsSysteme.h"      // Stat()
#include <time.h>

using namespace nsSysteme;  // wrappers
using namespace std;

namespace {
  string quelleHeureEstIl() {
    time_t cadran;
    time(&cadran);
    string heure (ctime(&cadran));
    heure . erase(heure.size() - 1);
    return heure;
  }
}

int main (int argc, char * argv [])
{
  try {
    if ((6 != argc && 8 != argc)                    ||
	(6 == argc && string("lire")   != argv [1]) ||
	(8 == argc && string("ecrire") != argv [1])) 
	throw CExc ("main()", string ("Usage : ") + argv [0] + 
			" {lire <combienALaFois>|ecrire <1erChar> " + 
			"<combienAuTotal> <delaiFinal>} <delaiInitial> <delai> <nomFic> ");
    
    if(string("lire") == argv [1]) {
      const unsigned int CstCombien  = atoi (argv [2]);
      const unsigned int CstDelaiIni = atoi (argv [3]);
      const unsigned int CstDelai    = atoi (argv [4]);
      const int fd                   = Open (argv[5], O_RDONLY);
      cout << "Debut lecture toutes les " << CstDelai 
	   << "s par " << CstCombien << " apres " << CstDelaiIni << "\n";
      ::sleep(CstDelaiIni);
      for(bool qContinue(true);qContinue;) {
	char c;
        // TRAVAIL A FAIRE
        // ---------------
        // boucle pour 
        //    lire depuis le descripteur fd, un caractere a la fois (utilisez sizeof())
        //    afficher aussitot chaque caractere lu, rappelant aussi les parametres de lancement
        //    mettre qContinue a faux lorsqu'on a atteint la fin du fichier
        ::sleep (CstDelai);
      }
      Close(fd);
    }
    else if(string("ecrire") == argv [1]) {
      unsigned int NbCarac           = atoi (argv [3]);
      const unsigned int CstDelaiFin = atoi (argv [4]);
      const unsigned int CstDelaiIni =  atoi(argv [5]);
      const unsigned int CstDelai    = atoi (argv [6]);
      const int fd                   = Open (argv[7], O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, 0700);
      cout << "Debut ecriture toutes les " << CstDelai 
	   << "s de " << NbCarac << " apres " << CstDelaiIni << "\n";
      ::sleep(CstDelaiIni);
      for (char Deb = argv [2][0]; NbCarac--; ++Deb) {
	Write (fd, & Deb, 1); 
	cout << " Ecriture a " << quelleHeureEstIl() << " du caractere '" << Deb << "'\n";
        ::sleep (CstDelai);
      }
      ::sleep(CstDelaiFin);
      Close(fd);
      cout << "Ecriture toutes les " << CstDelai << " apres " << CstDelaiIni << " terminee a "
	   << quelleHeureEstIl() << ".\n";
    }
    else {
	throw CExc ("main()",string ("Usage : ") + argv [0] + 
			" {lire <combienALaFois>|ecrire <1erChar> " + 
			"<combienAuTotal>} <delaiInitial> <delai> <nomFic> ");
    }
    return 0;
  }
  catch (const CExc & Exc) {
        cerr <<Exc<< endl;
        return errno;
  }
  catch (const exception & Exc) {
        cerr << "Exception : " << Exc.what () << endl;
        return 1;
  }
  catch (...) {
        cerr << "Exception inconnue recue dans la fonction main()" 
             << endl;
        return 1;
  }


} // main()