package protocol

import "encoding/json"

// Field holds all necessary data for a field in a protocol
type Field struct {
	Name       string  // Name of the Field
	Desc       string  // Lengthy description
	Regex      string  // Regex to recognize values
	Size       int     // Size in bits!
	SubFields  []Field // Possible sub-fields
	Optional   bool    // Is this field required?
	Payload    bool    // Is this field the payload or next protocol level?
	JavaScript string
}

// FieldReferencer interface
type FieldReferencer interface {
	GetProtocolField() *Field
	SetProtocolField(f *Field)
}

// ToJSON converts a field to a JSON string
func (f *Field) ToJSON() string {
	b, err := json.Marshal(*f)
	if err != nil {
		return ""
	}
	return string(b)
}

// NewEmptyField just creates a new Field with no data
func NewEmptyField() *Field {
	f := Field{}
	return &f
}

// NewField creates a new Field with all data possible
func NewField(
	name string,
	desc string,
	regex string,
	size int,
	subfields []Field,
	optional bool,
	payload bool,
) *Field {
	f := Field{
		Name:      name,
		Desc:      desc,
		Regex:     regex,
		Size:      size,
		SubFields: subfields,
		Optional:  optional,
		Payload:   payload,
	}
	return &f
}