package notify

// Notification represents a message that can be sent to subscribers.
// Notifications contain metadata about the message (Level, Title),
// the content (Message, Details), and an optional Action field for
// custom application data.
type Notification struct {
	// Target specifies the subscriber ID to receive this notification.
	// If empty when passed to NotifyAll(), the notification is broadcast
	// to all subscribers. If set, only the targeted subscriber receives it.
	Target Target

	// Level indicates the notification severity (Success, Info, Warn, Error).
	Level Level

	// Title is a short summary of the notification.
	Title string

	// Message is the main notification content.
	Message string

	// Details contains additional information about the notification.
	Details string

	// Action is an optional field for custom application data.
	// This can be used to attach contextual information, callback functions,
	// URLs, or any other data needed by the notification handler.
	Action any
}

// Target is a unique identifier for a subscriber.
// Targets are automatically generated when a subscriber is created
// using cryptographic random bytes (16 bytes, base64 URL-encoded).
type Target string

// Level represents the severity or type of a notification.
type Level string

const (
	// LevelSuccess indicates a successful operation or positive outcome.
	LevelSuccess Level = "success"

	// LevelInfo indicates general informational messages.
	LevelInfo Level = "info"

	// LevelWarn indicates warnings that don't require immediate action.
	LevelWarn Level = "warn"

	// LevelError indicates errors that require attention.
	LevelError Level = "error"
)