Chrono MCP

import { DateTime } from "luxon"; /** * Common timezone identifiers */ export const COMMON_TIMEZONES = [ "UTC", "America/New_York", "America/Chicago", "America/Denver", "America/Los_Angeles", "Europe/London", "Europe/Paris", "Europe/Berlin", "Asia/Tokyo", "Asia/Shanghai", "Australia/Sydney", ] as const; /** * Format a DateTime object according to the specified format */ export function formatDateTime( dt: DateTime, format: string, locale?: string, ): string { switch (format) { case "iso": return dt.toISO() ?? ""; case "rfc2822": return dt.toRFC2822() ?? ""; case "http": return dt.toHTTP() ?? ""; case "sql": return dt.toSQL() ?? ""; case "local": return dt.toString(); case "localeString": return dt.toLocaleString(DateTime.DATETIME_FULL, { locale }); case "short": return dt.toLocaleString(DateTime.DATETIME_SHORT, { locale }); case "medium": return dt.toLocaleString(DateTime.DATETIME_MED, { locale }); case "long": return dt.toLocaleString(DateTime.DATETIME_FULL, { locale }); case "full": return dt.toLocaleString(DateTime.DATETIME_HUGE, { locale }); default: return dt.toFormat(format, { locale }); } } /** * Get current time in specified timezone */ export function getCurrentTime(timezone?: string): DateTime { const now = DateTime.now(); return timezone ? now.setZone(timezone) : now; } /** * Parse a date/time string in a specific timezone */ export function parseDateTime(dateString: string, timezone?: string): DateTime { // Try multiple parsing strategies let dt: DateTime; // First try ISO format dt = DateTime.fromISO(dateString, { zone: timezone }); if (dt.isValid) return dt; // Try RFC2822 format dt = DateTime.fromRFC2822(dateString); if (dt.isValid && timezone) { return dt.setZone(timezone); } if (dt.isValid) return dt; // Try HTTP format dt = DateTime.fromHTTP(dateString); if (dt.isValid && timezone) { return dt.setZone(timezone); } if (dt.isValid) return dt; // Try SQL format dt = DateTime.fromSQL(dateString, { zone: timezone }); if (dt.isValid) return dt; // Try common formats const formats = [ "yyyy-MM-dd HH:mm:ss", "yyyy-MM-dd HH:mm", "yyyy-MM-dd", "MM/dd/yyyy HH:mm:ss", "MM/dd/yyyy HH:mm", "MM/dd/yyyy", "dd/MM/yyyy HH:mm:ss", "dd/MM/yyyy HH:mm", "dd/MM/yyyy", ]; for (const format of formats) { dt = DateTime.fromFormat(dateString, format, { zone: timezone }); if (dt.isValid) return dt; } // If all else fails, throw an error throw new Error(`Unable to parse datetime string: ${dateString}`); } /** * Format duration in milliseconds to human-readable string */ export function formatDuration(milliseconds: number): string { const absMs = Math.abs(milliseconds); const isNegative = milliseconds < 0; // Calculate all units const years = Math.floor(absMs / (1000 * 60 * 60 * 24 * 365.25)); const remainingAfterYears = absMs % (1000 * 60 * 60 * 24 * 365.25); const days = Math.floor(remainingAfterYears / (1000 * 60 * 60 * 24)); const hours = Math.floor((absMs % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60)); const minutes = Math.floor((absMs % (1000 * 60 * 60)) / (1000 * 60)); const seconds = Math.floor((absMs % (1000 * 60)) / 1000); const parts: string[] = []; // Add years if significant (more than 1 year) if (years > 0) parts.push(`${years} year${years !== 1 ? "s" : ""}`); // For very large spans (>10 years), only show years and days for readability if (years >= 10) { if (days > 0) parts.push(`${days} day${days !== 1 ? "s" : ""}`); } else { // For smaller spans, show more detail if (days > 0) parts.push(`${days} day${days !== 1 ? "s" : ""}`); if (hours > 0) parts.push(`${hours} hour${hours !== 1 ? "s" : ""}`); if (minutes > 0) parts.push(`${minutes} minute${minutes !== 1 ? "s" : ""}`); if (seconds > 0) parts.push(`${seconds} second${seconds !== 1 ? "s" : ""}`); } if (parts.length === 0) return "0 seconds"; const result = parts.join(", "); return isNegative ? `-${result}` : result; } /** * Validate if a string is a valid timezone */ export function isValidTimezone(timezone: string): boolean { try { Intl.DateTimeFormat(undefined, { timeZone: timezone }); return true; } catch { return false; } } /** * Normalize DateTime object to UTC for consistent duration/difference calculations * This ensures that timezone differences don't affect duration calculations */ export function normalizeToUTC(dt: DateTime): DateTime { if (!dt.isValid) { return dt; // Return invalid DateTime as-is } return dt.toUTC(); } /** * Normalize multiple DateTime objects to UTC for consistent calculations * This is a convenience function for batch normalization */ export function normalizeAllToUTC(datetimes: DateTime[]): DateTime[] { return datetimes.map(normalizeToUTC); }