// Writen by John Wasson
// Purpose is to calculate the fees for A.I. vs. Natural Breeding

// How much for drugs.
function calculate_cidr_cost()
{
   
  calc_form = document.fee_calculator;
  herdsize = calc_form.heifers_for_cidr.value;

  //check and make sure a herd size was entered
  if (herdsize == "")
  {
     alert("Need to enter the number of heifers being bred!");
     calc_form.heifers_for_cidr.focus();
     return false;
  }
  //perform the calculations
calc_form.cidr_cost_per_animal.value = Number(calc_form.cost_per_cidr.value) + 
									   Number(calc_form.cost_per_pgf.value) + 
									   Number(calc_form.semen_cost.value) + 
									   Number(calc_form.cidr_labor_cost.value);
calc_form.cidr_total_cost.value = calc_form.cidr_cost_per_animal.value * 
								  calc_form.heifers_for_cidr.value;
  return true;
}


// AI vs Natural

function calculate_fees()
{

  calc_form = document.fee_calculator;
  herdsize = calc_form.herd_size.value;
  unitspercowperyear = calc_form.units_per_cow_per_year.value
  //check and make sure a herd size was entered
  if (herdsize == "")
  {
     alert("Need to enter a herd size!");
     calc_form.herd_size.focus();
     return false;
  }
  //perform the calculations


calc_form.units_per_year.value = herdsize * unitspercowperyear;
calc_form.total_ai_costs.value = calc_form.labor_per_service.value * unitspercowperyear * herdsize + 
						 		 calc_form.units_per_year.value * calc_form.average_unit_cost.value;

bulls_needed = Math.round(herdsize / 40);
if (bulls_needed < 1 )
 { 
   bulls_needed = 1 ; 
 }

calc_form.bulls_needed.value = bulls_needed;
calc_form.bull_cost.value = bulls_needed * 1000;
yearly_maint = Math.round(bulls_needed * 3467.5);

calc_form.yearly_maint.value = yearly_maint;
calc_form.slaughter_value.value = calc_form.bulls_needed.value * 800;
calc_form.total_ni_costs.value = Number(calc_form.bull_cost.value) + Number(calc_form.yearly_maint.value) -
									Number(calc_form.slaughter_value.value);

calc_form.total_ai_savings.value = Number(calc_form.total_ni_costs.value) - Number(calc_form.total_ai_costs.value);

  return true;
}


// Days open part - work those cows.

function calculate_days_open()
{

  calc_form = document.fee_calculator;
  herdsize = calc_form.herd_size_days_open.value;

  //check and make sure a herd size was entered
  if (herdsize == "")
  {
     alert("Need to enter a herd size!");
     calc_form.herd_size_days_open.focus();
     return false;
  }
  //perform the calculations


calc_form.Cost_Per_Day_Times_Herd_Size.value = calc_form.cost_per_day.value * calc_form.herd_size_days_open.value;
calc_form.do_total.value = ( calc_form.average_days_open.value - calc_form.goal_for_average_days_open.value ) * calc_form.Cost_Per_Day_Times_Herd_Size.value;

  return true;
}