// /var/www/makearmy.io/app/app/laser-toolkit/_lib/conversions.ts

// ---------- DPI / LPI / DPCM ----------
export function dpiToLpi(dpi: number) {
  return dpi; // 1:1 if treating “lines” as rows in raster (common convention)
}
export function dpiToDpcm(dpi: number) {
  return dpi / 2.54;
}
export function lpiToDpi(lpi: number) {
  return lpi; // same note as above
}
export function lpiToDpcm(lpi: number) {
  return lpi / 2.54;
}
export function dpcmToDpi(dpcm: number) {
  return dpcm * 2.54;
}
export function dpcmToLpi(dpcm: number) {
  return dpcm * 2.54;
}

// ---------- Power & Lens Scaler ----------
// Simple “keep energy density roughly constant” heuristic:
// newSpeed ≈ oldSpeed * (toPower / fromPower) * (fromField / toField)
export function scaleSpeed(
  oldSpeed_mm_s: number,
  fromPower_W: number,
  toPower_W: number,
  fromField_mm: number,
  toField_mm: number
) {
  if (fromPower_W <= 0 || toPower_W <= 0 || fromField_mm <= 0 || toField_mm <= 0) {
    return oldSpeed_mm_s;
  }
  const k = (toPower_W / fromPower_W) * (fromField_mm / toField_mm);
  return oldSpeed_mm_s * k;
}