core.go

package lorem

import (
	"fmt"
	"math"
	"math/rand"
	"strconv"
	"time"
)

// generate random integer
func randomInteger(min, max int) (int, error) {
	rand.New(rand.NewSource(time.Now().UnixNano()))
	if max <= min {
		return 0, fmt.Errorf("min must be less than max. min: %d, max: %d", min, max)
	}
	return rand.Intn(max-min+1) + min, nil
}

// generate random float64 number
func randomFloat(min, max float64, decimal uint) (float64, error) {
	if max <= min {
		return 0.0, fmt.Errorf("min must be less than max. min: %v, max: %v", min, max)
	}

	d := math.Pow10(int(decimal))

	rand.New(rand.NewSource(time.Now().UnixNano()))
	random := rand.Float64()*(max-min) + min
	temp := strconv.FormatFloat(math.Trunc(random*d)/d, 'f', -1, 64)
	num, _ := strconv.ParseFloat(temp, 64)
	return num, nil
}

func randomElement[T any](arr []T) T {
	index, _ := randomInteger(0, len(arr)-1)
	return arr[index]
}