import dayjs from 'dayjs';
import size from 'lodash/size';

interface SpecialColors {
  [index: number]: string;
}

/**
 * Formats the number as currency, for example -10590 converts to "$10.59k".
 * @param value
 * @returns string
 */
const formatCurrency = (value?: number) => {
  if (!value) {
    return value === 0 ? '0' : '-';
  }
  if (value < 0) value *= -1;
  if (value >= 100 && value < 1000000) {
    return `$${Math.round((value / 1000 + Number.EPSILON) * 100) / 100}k`;
  } else if (value >= 1000000 && value < 1000000000) {
    return `$${Math.round((value / 1000000 + Number.EPSILON) * 100) / 100}m`;
  } else if (value >= 1000000000) {
    return `$${Math.round((value / 1000000000 + Number.EPSILON) * 100) / 100}b`;
  } else {
    return `$${value}`;
  }
};

/**
 * Converts a date-time string to a formatted date using the dayjs library.
 * @param value
 * @param format
 * @returns
 */
const formatDate = (value: string | Date, format = 'MMM DD, YYYY') =>
  dayjs(value).format(format);

/**
 * Converts a company size string to a human-readable value.
 * @param size
 * @returns
 */
const sizeToCompany = (size?: string) => {
  if (size) {
    switch (size.toLowerCase()) {
      case 'small': {
        return 'Small (0 < 50)';
      }
      case 'smb': {
        return 'SMB (0 < 50)';
      }
      case 'medium': {
        return 'Medium (50 < 200)';
      }
      case 'large': {
        return 'Large (200 < 1000)';
      }
      case 'enterprise': {
        return 'Enterprise (1000+)';
      }

      default:
        return size;
    }
  }

  return 'NA';
};

/**
 * Converts a username string to initials and color for user avatar.
 * @param userName
 * @param specialColors
 * @param alwaysTwoLetters Always return two-letter initials?
 * @returns
 */
const userNameToInitials = (
  userName: string,
  specialColors?: SpecialColors,
  alwaysTwoLetters = false
) => {
  const split = userName.split(' ');
  const first = split[0][0] || '';
  const second = split[1]?.[0] || (alwaysTwoLetters ? first : '');
  const initials = first + second;
  const specialColorsCount = specialColors && size(specialColors);
  const letterToCode = (letter?: string) =>
    (letter && parseInt(letter, 36)) || 0;
  const color =
    specialColors && specialColorsCount
      ? specialColors[
          ((letterToCode(first) + letterToCode(second)) % specialColorsCount) +
            1
        ]
      : '';
  return {
    color,
    first,
    initials,
    second
  };
};

const trimSpaces = (text: string | undefined) =>
  text ? text.replace(/\s/g, '') : undefined;

export {
  formatCurrency,
  formatDate,
  sizeToCompany,
  userNameToInitials,
  trimSpaces
};