/* Courtesy of sera.
 * Copyright (C) by sera, V 2005. All rights reserved.
 */

function rechne() {
 var m = 0;
 var kg = 0;
 var bmi = 0;
 var ft = 0;
 var i = 0;
 var lbs = 0;
 
 // Groesse lesen
 m = document.getElementById("m").value;
 ft = document.getElementById("ft").value;
 i = document.getElementById("in").value;

 // Gewicht / BMI lesen
 kg = document.getElementById("kg").value;
 lbs = document.getElementById("lbs").value;
 bmi = document.getElementById("bmi").value;

 // Groesse umrechnen
 if (m != 0) {
  if (m > 100) {
   m = m / 100;
   document.getElementById("m").value = m;
  }
  ftin = m * 100 / 30.479;
  ft = Math.floor(ftin);
  i = Math.round(12 * (ftin - ft));
  document.getElementById("ft").value = ft;
  document.getElementById("in").value = i;
 }
 else if (ft + i != 0) {
  m = (Math.round(ft * 30.479 + i * 2.54)) / 100;
  document.getElementById("m").value = m;
 }
 else if (lbs + kg == 0) {
  alert("So kann nichts berechnet werden. Bitte mehr Zahlen eingeben.");
  return false;
 }

 // Gewicht umrechnen, falls eingegeben
 if (kg != 0) {
  lbs = (Math.round(10 * kg * 2.2046)) / 10;
  document.getElementById("lbs").value = lbs;
 }
 else if (lbs != 0) {
  kg = (Math.round(10 * lbs / 2.2046)) / 10;
  document.getElementById("kg").value = kg;
 }

 // Wenn Gewicht + Groesse eingegeben, BMI ausrechnen
 if (kg != 0 && m != 0) {
  bmi = (Math.round(10 * kg / (m * m))) / 10;
  document.getElementById("bmi").value = bmi;
 }

 if (bmi != 0) {
  if (kg != 0 && m == 0) {
   // Groesse aus BMI und Gewicht berechnen
   m = (Math.round(100 * Math.sqrt(kg / bmi))) / 100;
   ftin = m * 100 / 30.479;
   ft = Math.floor(ftin);
   i = Math.round(12 * (ftin - ft));
   document.getElementById("ft").value = ft;
   document.getElementById("in").value = i;
   document.getElementById("m").value = m;
  }
  if (m != 0 && kg == 0) {
   // Gewicht aus BMI und Groesse berechnen
   kg = (Math.round(10 * bmi * m * m)) / 10;
   lbs = (Math.round(10 * kg * 2.2046)) / 10;
   document.getElementById("kg").value = kg;
   document.getElementById("lbs").value = lbs;
  }
 }
 return false;
}



function kill(nr) {
 switch(nr) {
  case 1:
   document.getElementById("m").value = "";
   document.getElementById("ft").value = "";
   document.getElementById("in").value = "";
  break;
  case 2:
   document.getElementById("kg").value = "";
   document.getElementById("lbs").value = "";
  break;
  case 3:
   document.getElementById("bmi").value = "";
  break;
  case 4:
   document.getElementById("m").value = "";
   document.getElementById("kg").value = "";
   document.getElementById("bmi").value = "";
  break;
  case 5:
   document.getElementById("ft").value = "";
   document.getElementById("in").value = "";
   document.getElementById("lbs").value = "";
  break;
  case 6:
   document.getElementById("ft").value = "";
   document.getElementById("in").value = "";
  break;
  case 7:
   document.getElementById("m").value = "";
  break;
  case 8:
   document.getElementById("lbs").value = "";
  break;
  case 9:
   document.getElementById("kg").value = "";
  break;
  default:
   alert("Ups, Fehler im Script.");
  break;
 }
}