/**
 * Convert the date format of YYYY-MM-DD to American writing
 * @param date The date in format of YYYY-MM-DD.
 */
export const normalizeDate = (date = "1970-01-01"): string => {
  const [year, month, day] = date.split("-");
  const month_num = Number.parseInt(month);
  const day_num = Number.parseInt(day);
  const month_en: {
    [index: number]: string;
  } = {
    1: "January",
    2: "February",
    3: "March",
    4: "April",
    5: "May",
    6: "June",
    7: "July",
    8: "August",
    9: "September",
    10: "October",
    11: "November",
    12: "December",
  };
  return `${month_en[month_num]} ${day_num}, ${year}`;
};

export const getCurrentTime = (): {
  year: string;
  month: string;
  day: string;
  hours: string;
  minutes: string;
  seconds: string;
} => {
  const today = new Date();
  return {
    year: today.getFullYear().toString(),
    month: String(today.getMonth() + 1).padStart(2, "0"),
    day: String(today.getDate()).padStart(2, "0"),
    hours: String(today.getHours()).padStart(2, "0"),
    minutes: String(today.getMinutes()).padStart(2, "0"),
    seconds: String(today.getSeconds()).padStart(2, "0"),
  };
};

export const convertDateToISO8601 = (dateString: string, timezoneOffset = 8): string => {
  const date = new Date(dateString);

  const offsetHours = timezoneOffset;
  const offsetMinutes = offsetHours * 60;

  date.setMinutes(date.getMinutes() + offsetMinutes);

  const isoString = date.toISOString();

  const datePart = isoString.split("T")[0];
  const timePart = "00:00:00";

  const offsetSign = offsetHours >= 0 ? "+" : "-";
  const absOffsetHours = Math.abs(offsetHours).toString().padStart(2, "0");
  const offsetString = `${offsetSign}${absOffsetHours}:00`;

  return `${datePart}T${timePart}${offsetString}`;
};