// Package roomid defines the room identifier format shared by gateway and room-service.
package roomid

const (
	// MaxStringIDLength keeps room_id within both Tencent IM GroupID and RTC strRoomId limits.
	MaxStringIDLength = 48
)

// ValidStringID reports whether value can be used as the internal room_id and Tencent room identifier.
func ValidStringID(value string) bool {
	if len(value) == 0 || len(value) > MaxStringIDLength {
		return false
	}

	for i := 0; i < len(value); i++ {
		char := value[i]
		if char >= 'a' && char <= 'z' {
			continue
		}
		if char >= 'A' && char <= 'Z' {
			continue
		}
		if char >= '0' && char <= '9' {
			continue
		}
		if char == '_' || char == '-' {
			continue
		}

		return false
	}

	return true
}