#include <stdio.h>
  #include <wiringPi.h>
  #include <stdlib.h>
  #include <string.h>
  #include <stdbool.h>
  
  void add_caract(char word[], char caract)
  {
  	char str[2];
  	str[0] = caract;
  	str[1] = '\0';
  	strcat(word, str);
  }
  
  void read_xml(FILE* fp, char sensor[])
  {
    char c;
    int cpt=0;
    while(1)
      {
        c = fgetc(fp);
        if(c=='>') cpt++;
        if(cpt==2) break;
      }
    while(1)
      {
        c = fgetc(fp);
        if(c=='<') break;
        add_caract(sensor, c);
      }
  }
  
  bool verif()
  {
      FILE* fpv = fopen("verif.txt", "r");
      FILE* fpd = fopen("demande.txt", "r");
      
      if(fpv==NULL || fpd==NULL) return false;
      
      char v[2];
      char d[2];
      
      fgets(v, 3, fpv);
      fgets(d, 3, fpd);
      
      //char cv = fgetc(fpv);
      //char cd = fgetc(fpd);
      
      fclose(fpv);
      fclose(fpd);
      FILE* fp = fopen("verif.txt", "w+");
      
      //add_caract(v, cv);
      //add_caract(d, cd);
      
      int verif = atoi(v);
      int demande = atoi(d);
      
      if(verif!=demande) 
        fputs(d, fp);
      else
        fputs(v, fp);
      
      return(verif!=demande);
  }
  
  int pin_num()
  {
    FILE* fp = fopen("sensor.xml", "r");
    if(fp==NULL) return EXIT_FAILURE;
    
    char sensor[15] = "";
    char nb[2]="";
    read_xml(fp, sensor);
  
    // Vérification présence du capteur/pin sur la RPi
    
    add_caract(nb, sensor[strlen(sensor)-1]);
    if(verif())
      return atoi(nb);
    else
      return 4;
  }
  
  int main(void)
  {
    int pin=pin_num();
    FILE* fp = fopen("stock.txt", "w+");
    fprintf(fp, "%d", pin);
    return 0;
  }