#include <iostream>
#include <fstream>

using namespace std;

// upper and lower limits for diagnosis
const double CHILD_UPPER   = 4800000.0;
const double CHILD_LOWER   = 4600000.0;
const double MALE_UPPER    = 6100000.0;
const double MALE_LOWER    = 4700000.0;
const double FEMALE_UPPER  = 4200000.0;
const double FEMALE_LOWER  = 5400000.0;
// if we have to make changes all the numbers are right here in one place

void diagnoseAdult(string, string, double);// function prototypes only need types
void diagnoseLimits(string name, double rbcs, double lower, double upper);
// parameter names are optional
void printInputData(string name, string gender, double age, double rbcs);

int main(){

  string inputFilename;
  cout << "Enter subject's filename" << endl;
  cin >> inputFilename; // read filename from user

  fstream in;
  string name, gender;
  int age, rbcCountTmp;
  double rbcCount;

  in.open(inputFilename.c_str()); // open file
  if(!in){                        // Must ERROR check
    cout << "Error in opening file: " << inputFilename << endl;
    cout << "Exiting...." << endl;
    return -1;
  }
  in >> name;                     // read data
  in >> gender;
  in >> age;
  in >> rbcCountTmp;
  in.close();                     // MUST close file

  rbcCount = rbcCountTmp * 100000.0; // convert to millions of RBCs per micro litre

  printInputData(name, gender, age, rbcCount);
  //let's write what we read, to inform user. It also helps with debugging!
  
  if(age >= 18){
    diagnoseAdult(name, gender, rbcCount); // diagnose adults
  } else {
    diagnoseLimits(name, rbcCount, CHILD_LOWER, CHILD_UPPER); // check child limits
  }
  return 0;
}

/* Check if male or female and call diagnoseLimits with appropriate limits
 */
void diagnoseAdult(string name, string gender, double rbcs){
  if(gender == "male"){
    diagnoseLimits(name, rbcs, MALE_LOWER, MALE_UPPER);// check limits for adult male
  } else {
    diagnoseLimits(name, rbcs, FEMALE_LOWER, FEMALE_UPPER);// check limits for adult female
  }
}

/* Check whether rbcs is within lower and upper limits and print appropriate
   diagnosis message for name.
 */
void diagnoseLimits(string name, double rbcs, double lower, double upper){
  if (rbcs < lower){
    cout << name << " has anemia" << endl; // uh oh, too few
  } else if (rbcs > upper){
    cout << name << " has polycythemia" << endl; // uh oh, too many
  } else {
    cout << name << " has a normal RBC count" << endl; // just right!
  }
  cout << endl;
  return;
}


/* 
   Pretty print subject's information
*/
void printInputData(string name, string gender, double age, double rbcs){
  cout << "---------------------------------------------------------------------------"
       << endl;
  cout << "Subject name: " << name << endl;
  cout << "      gender: " << gender << endl;
  cout << "         age: " << age << endl;
  cout << "         has: " << rbcs 
       << " Red Blood Cells per micro litre of blood" 
       << endl << endl;
}