import { Injectable } from '@angular/core';
import { evaluate, round } from 'mathjs';

@Injectable({
  providedIn: 'root',
})
export class MathService {
  parseAmount(amount: string = '', rounding: number = 2): number {
    const cleaned = `${amount}`.replace(new RegExp('(₹[s]*)|(,)|(s)', 'g'), '');
    if (cleaned === '') {
      return 0;
    }
    return round(evaluate(cleaned), rounding);
  }

  halfRoundEven(x: number, n = 0): number {
    const fraction = Math.round(x * Math.pow(10, n + 8)) % Math.pow(10, 8);
    if (fraction > 50000000 - 1 && fraction < 50000000 + 1) {
      // To compensate for floating point rounding errors
      const floor = Math.floor(x * Math.pow(10, n));
      return floor % 2 === 0 ? floor / Math.pow(10, n) : (floor + 1) / Math.pow(10, n);
    } else {
      return round(x, n);
    }
  }
}