// Utility functions for Litter Scouts

// Re-export coordinate utilities
export * from './coordinates';
export * from './performance';

/**
 * Formats a date to ISO 8601 format
 */
export function formatDateISO(date: Date): string {
  return date.toISOString();
}

/**
 * Calculates distance between two coordinates in meters using Haversine formula
 */
export function calculateDistance(
  lat1: number,
  lng1: number,
  lat2: number,
  lng2: number
): number {
  const R = 6371e3; // Earth's radius in meters
  const φ1 = (lat1 * Math.PI) / 180;
  const φ2 = (lat2 * Math.PI) / 180;
  const Δφ = ((lat2 - lat1) * Math.PI) / 180;
  const Δλ = ((lng2 - lng1) * Math.PI) / 180;

  const a =
    Math.sin(Δφ / 2) * Math.sin(Δφ / 2) +
    Math.cos(φ1) * Math.cos(φ2) * Math.sin(Δλ / 2) * Math.sin(Δλ / 2);
  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));

  return R * c;
}

/**
 * Validates file type for photo uploads
 */
export function isValidImageFile(file: File): boolean {
  const validTypes = ['image/jpeg', 'image/jpg', 'image/png', 'image/webp'];
  return validTypes.includes(file.type);
}

/**
 * Validates file size (max 5MB)
 */
export function isValidFileSize(file: File, maxSizeMB: number = 5): boolean {
  const maxSizeBytes = maxSizeMB * 1024 * 1024;
  return file.size <= maxSizeBytes;
}

/**
 * Formats bytes to human-readable size
 */
export function formatFileSize(bytes: number): string {
  if (bytes === 0) return '0 Bytes';
  const k = 1024;
  const sizes = ['Bytes', 'KB', 'MB', 'GB'];
  const i = Math.floor(Math.log(bytes) / Math.log(k));
  return Math.round(bytes / Math.pow(k, i) * 100) / 100 + ' ' + sizes[i];
}