package com.trafficaudit.holiday;

import org.apache.poi.ss.util.NumberToTextConverter;

import java.math.BigDecimal;
import java.math.MathContext;
import java.math.RoundingMode;

public final class HolidayNumberUtils {

    public static final MathContext EXCEL_MC = new MathContext(15, RoundingMode.HALF_UP);
    public static final BigDecimal ZERO = BigDecimal.ZERO;

    private HolidayNumberUtils() {
    }

    public static BigDecimal excelValue(double value) {
        return normalize(new BigDecimal(NumberToTextConverter.toText(value)));
    }

    public static BigDecimal decimalValue(Object value) {
        if (value == null || value.toString().trim().isEmpty()) return null;
        return normalize(new BigDecimal(value.toString().trim()));
    }

    public static BigDecimal normalize(BigDecimal value) {
        if (value == null) return null;
        BigDecimal rounded = value.round(EXCEL_MC);
        return rounded.signum() == 0 ? ZERO : rounded.stripTrailingZeros();
    }

    public static BigDecimal valueOrZero(BigDecimal value) {
        return value == null ? ZERO : value;
    }

    public static BigDecimal sumNullable(BigDecimal left, BigDecimal right) {
        if (left == null && right == null) return null;
        return normalize(valueOrZero(left).add(valueOrZero(right)));
    }

    public static BigDecimal multiply(BigDecimal left, BigDecimal right) {
        if (left == null || right == null) return null;
        return normalize(left.multiply(right));
    }

    public static BigDecimal divide(BigDecimal dividend, BigDecimal divisor) {
        if (dividend == null || divisor == null || divisor.signum() == 0) return null;
        return normalize(dividend.divide(divisor, EXCEL_MC));
    }

    public static boolean sameValue(BigDecimal left, BigDecimal right) {
        if (left == null || right == null) return false;
        return normalize(left).compareTo(normalize(right)) == 0;
    }

    public static String changeText(BigDecimal value) {
        if (value == null) return "";
        return normalize(value).toPlainString();
    }

    public static String format1(BigDecimal value) {
        if (value == null) return "";
        return value.setScale(1, RoundingMode.HALF_UP).toPlainString();
    }

    public static String format2(BigDecimal value) {
        if (value == null) return "";
        return value.setScale(2, RoundingMode.HALF_UP).toPlainString();
    }
}