/*
[] implement logTemperature()
  [x] take current loop iteration as argument
  [x] print "Enter temperature log #X:"
  [x] take temperature as int
  [x] if higher / lower than constants, print "Temperature X is impossible\n"
  [x] if higher / lower than constants, ask user again
  [x] if valid, print "Logged temperature: X degree Celsius\n"
[x] implement calculateAbsoluteDifference()
  [x] take two int as argument
  [x] return absolute difference

Example:
Welcome to the temperature logger!
Enter temperature log #1:-300
Temperature -300 is impossible
Enter temperature log #1:30
Logged temperature: 30 degree Celsius
Enter temperature log #2:20
Logged temperature: 20 degree Celsius
Enter temperature log #3:50000
Temperature 50000 is impossible
Enter temperature log #3:25
Logged temperature: 25 degree Celsius
The difference of min/max values is 10
*/

#include <stdio.h>

#define LOWEST_POSSIBLE_TEMPERATURE (-273) // absolute zero
#define HIGHEST_POSSIBLE_TEMPERATURE (6000) // approx. temperature of sun's photosphere (of course, temperatures can get higher)
#define MAX_ITERATION 3

int logTemperature(int current_iteration);
int calculateAbsoluteDifference(int minimum, int maximum);

int main(void)
{
  printf("Welcome to the temperature logger!\n");
  int cur_min = HIGHEST_POSSIBLE_TEMPERATURE; // initialize with highest value to find lower values
  int cur_max = LOWEST_POSSIBLE_TEMPERATURE; // initialize with lowest value to find high values

  for (int log_index = 0; log_index < MAX_ITERATION; ++log_index)
  {
    int temp = logTemperature(log_index + 1); // +1 to start with 1 instead of 0
    if(temp < cur_min)
    {
      cur_min = temp;
    }
    if(temp > cur_max)
    {
      cur_max = temp;
    }
  }

  int diff = calculateAbsoluteDifference(cur_min, cur_max);
  printf("The difference of min/max values is %d\n", diff);
  return 0;
}

int calculateAbsoluteDifference(int minimum, int maximum)
{
  return maximum - minimum;
}

int logTemperature(int current_iteration)
{
  int temperature = 0;

  printf("Enter temperature log #%d:", current_iteration);
  scanf("%d", &temperature);
  
  if(temperature > HIGHEST_POSSIBLE_TEMPERATURE || temperature < LOWEST_POSSIBLE_TEMPERATURE)
  {
    printf("Temperature %d is impossible\n", temperature);
    temperature = logTemperature(current_iteration);
  }
  else
  {
    printf("Logged temperature: %d degree Celsius\n", temperature);
  }
  
  return temperature;
}