import moment from 'moment';
import { TimeUnits } from '../enums';
import { ProgressExpiration, ProgressExpirationTitle } from '../models';

export class ProgressExpirationHelper {
  // Default value type and theme
  static initializeConfigDefaults(
    config: ProgressExpiration
  ): ProgressExpiration {
    config.startDate = config.startDate ?? new Date();
    config.type = config.type ?? 'small';
    config.theme = config.theme ?? 'light';
    return config;
  }

  // total days between start, expire, and optionally completed date
  static calculateTotalDays(
    startDate: Date,
    expireDate: Date,
    completedDate?: Date
  ): number {
    if (completedDate) {
      return moment
        .utc(expireDate)
        .diff(moment.utc(completedDate), TimeUnits.DAYS);
    } else {
      return moment.utc(expireDate).diff(moment.utc(startDate), TimeUnits.DAYS);
    }
  }

  // Left days
  static calculateLeftDays(expireDate: Date, completedDate?: Date): number {
    const today = moment().utc();
    const expireMoment = moment.utc(expireDate);
    const completedMoment = completedDate ? moment.utc(completedDate) : null;

    if (completedMoment && completedMoment.isBefore(expireMoment)) {
      return expireMoment.diff(completedMoment, TimeUnits.DAYS);
    } else if (completedMoment && completedMoment.isSame(expireMoment)) {
      return 0;
    } else if (completedMoment && completedMoment.isAfter(expireMoment)) {
      return expireMoment.diff(completedMoment, TimeUnits.DAYS);
    }

    return expireMoment.diff(today, TimeUnits.DAYS);
  }

  // Hours between start and expire date
  static calculateHours(expireDate: Date, startDate: Date): number {
    const startDay = moment(startDate);
    const expireDay = moment(expireDate);

    return expireDay.diff(startDay, TimeUnits.HOURS);
  }

  // The number of days in the current month
  static calculateDaysInCurrentMonth(): number {
    const today = new Date();
    const year = today.getFullYear();
    const month = today.getMonth();

    return new Date(year, month + 1, 0).getDate();
  }
}