package main

import (
	"fmt"
	cockroachdb "github.com/cockroachdb/apd"
	ericlagergren "github.com/ericlagergren/decimal"
	"github.com/rin01/decnum"
	shopspring "github.com/shopspring/decimal"
	"strconv"
	"testing"
)

func BenchmarkFloat(b *testing.B) {
	price := 10000.0
	var unit float64 = 1.3492720137776864
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		priceMulUnit := price * unit
		expectedPrice := priceMulUnit / unit
		// always false
		//if (expectedPrice != price) {
		//	b.Error("Not equal")
		//}
		priceDivUnit := price / unit
		expectedPrice = priceDivUnit * unit
		// always false
		//if (expectedPrice != price) {
		//	b.Error("Not equal")
		//}
		strconv.FormatFloat(expectedPrice*unit, 'f', -1, 64)
	}
}

func BenchmarkEricLagergren(b *testing.B) {
	price := ericlagergren.Big{}
	price.SetString("10000.0")
	unit := ericlagergren.Big{}
	unit.SetString("1.3492720137776864")
	//zero := ericlagergren.New(0, 0)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		//price.Cmp(zero)
		//price.Cmp(price)
		var priceQuoUnit ericlagergren.Big
		priceQuoUnit.Quo(&price, &unit)
		var expectedPrice ericlagergren.Big
		expectedPrice.Mul(&priceQuoUnit, &unit)
		fmt.Println(expectedPrice)
		fmt.Println(price)
		if (expectedPrice.Cmp(&price) != 0) {
			b.Error("Not equal")
		}
		var priceMulUnit ericlagergren.Big
		priceMulUnit.Mul(&price, &unit)
		expectedPrice.Quo(&priceMulUnit, &unit)
		fmt.Println(expectedPrice)
		fmt.Println(price)
		if (expectedPrice.Cmp(&price) != 0) {
			b.Error("Not equal")
		}
		expectedPrice.String()
	}
}

func BenchmarkShopSpring(b *testing.B) {
	price, _ := shopspring.NewFromString("10000.0")
	unit, _ := shopspring.NewFromString("1.3492720137776864")
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		//price.IsZero()
		//price.Cmp(price)
		priceDivUnit := price.Div(unit)
		expectedPrice := priceDivUnit.Mul(unit)
		expectedPrice.String()
		if (!expectedPrice.Equal(price)) {
			b.Error("Not equal")
		}
		priceMulUnit := price.Mul(unit)
		expectedPrice = priceMulUnit.Div(unit)
		expectedPrice.String()
		if (!expectedPrice.Equal(price)) {
			b.Error("Not equal")
		}

	}
}

func BenchmarkCockroachdb(b *testing.B) {
	// *** INC precision to pass the test! ****
	prec := uint32(9)
	c := cockroachdb.BaseContext.WithPrecision(prec)

	price, _, _ := cockroachdb.NewFromString("10000.0")
	unit, _, _ := cockroachdb.NewFromString("1.3492720137776864")
	b.ResetTimer()

	var priceMulUnit cockroachdb.Decimal
	var priceQuoUnit cockroachdb.Decimal
	var expectedPrice cockroachdb.Decimal
	var result cockroachdb.Decimal

	for i := 0; i < b.N; i++ {
		//price.IsZero()
		//c.Cmp(price,price, price)
		c.Quo(&priceQuoUnit, price, unit)
		c.Mul(&expectedPrice, &priceQuoUnit, unit)
		c.Cmp(&result, price, &expectedPrice)
		if (!result.IsZero()) {
			b.Error("Not equal")
		}

		c.Mul(&priceMulUnit, price, unit)
		c.Quo(&expectedPrice, &priceMulUnit, unit)
		c.Cmp(&result, price, &expectedPrice)
		if (!result.IsZero()) {
			b.Error("Not equal")
		}

		price.String()
	}
}

func BenchmarkDecnum(b *testing.B) {
	price, _ := decnum.FromString("10000.0")
	unit, _ := decnum.FromString("1.3492720137776864")
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		//price.IsZero()
		//price.Equal(price)
		priceDivUnit := price.Div(unit)
		expectedPrice := priceDivUnit.Mul(unit)
		expectedPrice.String()
		if (!price.Equal(expectedPrice)) {
			b.Error("Not equal")
		}
		priceMulUnit := price.Mul(unit)
		expectedPrice = priceMulUnit.Div(unit)
		expectedPrice.String()
		if (!price.Equal(expectedPrice)) {
			b.Error("Not equal")
		}
	}
}