단위 변환기 - 길이, 무게, 온도 & 데이터 크기 온라인

// Unit conversion utilities

function convert(value, fromUnit, toUnit, factors) {
  const baseValue = value * factors[fromUnit];
  return baseValue / factors[toUnit];
}

// Length factors (base: meter)
const lengthFactors = {
  mm: 0.001, cm: 0.01, m: 1, km: 1000,
  in: 0.0254, ft: 0.3048, yd: 0.9144, mi: 1609.344,
};

console.log(convert(100, 'cm', 'm', lengthFactors));   // 1
console.log(convert(1, 'mi', 'km', lengthFactors));     // 1.609344

// Temperature (special formulas)
function convertTemperature(value, from, to) {
  let celsius;
  if (from === 'C') celsius = value;
  else if (from === 'F') celsius = (value - 32) * 5 / 9;
  else if (from === 'K') celsius = value - 273.15;

  if (to === 'C') return celsius;
  if (to === 'F') return celsius * 9 / 5 + 32;
  if (to === 'K') return celsius + 273.15;
}

console.log(convertTemperature(100, 'C', 'F'));  // 212
console.log(convertTemperature(32, 'F', 'C'));   // 0

// Data size with binary/decimal toggle
function convertDataSize(value, fromUnit, toUnit, binary = true) {
  const base = binary ? 1024 : 1000;
  const units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB'];
  const fromIndex = units.indexOf(fromUnit);
  const toIndex = units.indexOf(toUnit);
  return value * Math.pow(base, fromIndex - toIndex);
}

console.log(convertDataSize(1, 'GB', 'MB', true));   // 1024
console.log(convertDataSize(1, 'GB', 'MB', false));  // 1000