// Required string: always .min(1) — empty string is invalid
name: z.string().min(1, "Name is required").max(255)

// Optional nullable: fields that can be undefined OR null
notes: z.string().max(1000).optional().nullable()

// IDs: simple string
id: z.string()
userId: z.string()

// Numbers with constraints
count: z.number().int().min(0).max(1000)
rating: z.number().min(1).max(5)

// Optional with default
limit: z.number().min(1).max(100).optional().default(10)

// HTTPS URL
websiteUrl: z.url()
  .refine((u) => new URL(u).protocol === "https:", "Must use HTTPS")
  .optional()

// Email validation
email: z.string().email()

// Enumeration with limited values
status: z.enum(["active", "inactive", "pending"])

// Reusable schema composition
const addressSchema = z.object({
  street: z.string().min(1),
  city: z.string().min(1),
  zipCode: z.string().regex(/^\d{5}(-\d{4})?$/, "Invalid ZIP code"),
})

const userSchema = z.object({
  name: z.string().min(1),
  email: z.string().email(),
  address: addressSchema,
})

// Always use safeParse() in forms — never throws
const result = schema.safeParse(formData);

if (!result.success) {
  // result.error contains field-level errors
  return { errors: result.error.flatten().fieldErrors };
}

// Use inferred type for form data
const data: z.infer<typeof schema> = result.data;