/**
 * Form validation utilities
 */

/**
 * Validate email format
 */
export function isValidEmail(email: string): boolean {
  const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
  return emailRegex.test(email);
}

/**
 * Validate password strength
 */
export function validatePassword(password: string): {
  isValid: boolean;
  errors: string[];
} {
  const errors: string[] = [];
  
  if (password.length < 8) {
    errors.push("Password must be at least 8 characters long");
  }
  
  // Optional: Add more password requirements
  // if (!/[A-Z]/.test(password)) {
  //   errors.push("Password must contain at least one uppercase letter");
  // }
  // if (!/[a-z]/.test(password)) {
  //   errors.push("Password must contain at least one lowercase letter");
  // }
  // if (!/[0-9]/.test(password)) {
  //   errors.push("Password must contain at least one number");
  // }
  
  return {
    isValid: errors.length === 0,
    errors,
  };
}

/**
 * Check if two passwords match
 */
export function passwordsMatch(password: string, confirmation: string): boolean {
  return password === confirmation && password.length > 0;
}

/**
 * Validate display name
 */
export function isValidDisplayName(name: string): boolean {
  return name.trim().length >= 1 && name.trim().length <= 50;
}

/**
 * Sanitize user input (basic XSS prevention)
 */
export function sanitizeInput(input: string): string {
  return input
    .replace(/</g, "&lt;")
    .replace(/>/g, "&gt;")
    .replace(/"/g, "&quot;")
    .replace(/'/g, "&#x27;")
    .replace(/\//g, "&#x2F;");
}

/**
 * Check if string is a valid URL
 */
export function isValidUrl(url: string): boolean {
  try {
    new URL(url);
    return true;
  } catch {
    return false;
  }
}

/**
 * Validate file type for uploads
 */
export function isValidImageType(file: File): boolean {
  const validTypes = ["image/jpeg", "image/jpg", "image/png", "image/gif", "image/webp"];
  return validTypes.includes(file.type);
}

/**
 * Validate file size (in bytes)
 */
export function isValidFileSize(file: File, maxSizeMB: number = 5): boolean {
  const maxBytes = maxSizeMB * 1024 * 1024;
  return file.size <= maxBytes;
}