package decimal

import (
	"github.com/shopspring/decimal"
)

// Div 除以
func Div(numerator, denominator int64) decimal.Decimal {
	num, den := decimal.NewFromInt(numerator), decimal.NewFromInt(denominator)
	return num.Div(den)
}

// Percent 百分额
func Percent(numerator, denominator int64) decimal.Decimal {
	return Div(numerator, denominator).Mul(decimal.NewFromFloat(100))
}

// Chain 环比
func Chain(numerator, denominator int64) decimal.Decimal {
	num, den := decimal.NewFromInt(numerator), decimal.NewFromInt(denominator)
	return num.Sub(den).Div(den)
}

// DenZero 分母0处理
func DenZero(numerator, denominator, max int64) (decimal.Decimal, bool) {
	if denominator != 0 {
		return decimal.Decimal{}, false
	}

	if numerator == 0 {
		return decimal.Zero, true
	}

	if numerator > max {
		numerator = max
	}

	return decimal.NewFromInt(max), true
}