How to Build a Mini Split Calculator

const CEILING_FACTOR = { '8': 1.0, '9': 1.12, '10': 1.25, 'vaulted': 1.4 };
  const INSULATION_FACTOR = { poor: 1.3, average: 1.0, good: 0.85, excellent: 0.75 };
  const CLIMATE_ZONE = { '1-2': 1.2, '3-4': 1.0, '5-6': 1.15, '7': 1.3 };
  const SUN_FACTOR = { heavy: 1.1, average: 1.0, shaded: 0.9 };
  const STANDARD_SIZES = [9000, 12000, 18000, 24000, 36000, 48000];

  function calculateMiniSplitBTU(inputs) {
  const { sqft, ceilingHeight, insulation, climateZone, sunExposure, occupants = 2, hasKitchen = false } = inputs;

  let btu = sqft * 25; // base calculation
  btu *= CEILING_FACTOR[ceilingHeight] || 1.0;
  btu *= INSULATION_FACTOR[insulation] || 1.0;
  btu *= CLIMATE_ZONE[climateZone] || 1.0;
  btu *= SUN_FACTOR[sunExposure] || 1.0;

  // Occupancy adjustment
  if (occupants > 2) btu += (occupants - 2) * 600;

  // Kitchen heat load
  if (hasKitchen) btu += 4000;

  // Round up to nearest standard size
  const recommendedSize = STANDARD_SIZES.find(size => size >= btu) || STANDARD_SIZES[STANDARD_SIZES.length - 1];

  return {
    calculatedBTU: Math.round(btu),
    recommendedSize,
    tonnage: (recommendedSize / 12000).toFixed(1),
    multiZone: btu > 36000 // suggest multi-zone if load exceeds single unit
  };
  }