/*
macli - Unofficial CLI-Based MyAnimeList Client
Copyright © 2022-2024 Vidhu Kant Sharma <vidhukant@vidhukant.com>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/

package util

import (
  "fmt"
  "os"
  "strconv"
)

func ParseNumeric(input string, prevValue int) int {
  inputInt, err := strconv.Atoi(input)
  if err != nil {
    fmt.Println("Error while parsing input", err)
    os.Exit(1)
  }

  switch input[0:1] {
  case "+", "-":
    // works both for increment and decrement
    return prevValue + inputInt
  default:
    return inputInt
  }
}