const MIN_DIMENSION_CM = 1;
const MAX_DIMENSION_CM = 150;
const MIN_WEIGHT_KG = 0.01;

const DIMENSION_UNIT_TO_CM: Record<string, number> = {
	mm: 0.1,
	cm: 1,
	m: 100,
	in: 2.54,
	yd: 91.44,
};

const WEIGHT_UNIT_TO_KG: Record<string, number> = {
	kg: 1,
	g: 0.001,
	lb: 0.45359237,
	lbs: 0.45359237,
	oz: 0.028349523125,
};

function roundForInput(value: number): number {
	return Number(value.toFixed(6));
}

function cmToStoreUnit(cm: number, dimensionUnit: string): number {
	const unitFactor = DIMENSION_UNIT_TO_CM[dimensionUnit] ?? 1;
	return cm / unitFactor;
}

function kgToStoreUnit(kg: number, weightUnit: string): number {
	const kgPerUnit = WEIGHT_UNIT_TO_KG[weightUnit] ?? 1;
	return kg / kgPerUnit;
}

export function getDimensionBounds(dimensionUnit: string): { min: number; max: number; step: number } {
	const min = roundForInput(cmToStoreUnit(MIN_DIMENSION_CM, dimensionUnit));
	const max = roundForInput(cmToStoreUnit(MAX_DIMENSION_CM, dimensionUnit));

	return {
		min,
		max,
		step: min,
	};
}

export function getWeightBounds(weightUnit: string): { min: number; step: number } {
	const min = roundForInput(kgToStoreUnit(MIN_WEIGHT_KG, weightUnit));

	return {
		min,
		step: min,
	};
}