package wire

import (
	"fmt"
	"io"
)

// MsgFilterClear implements the Message interface and represents a bitcoin filterclear message which is used to reset a
// Bloom filter. This message was not added until protocol version BIP0037Version and has no payload.
type MsgFilterClear struct{}

// BtcDecode decodes r using the bitcoin protocol encoding into the receiver. This is part of the Message interface
// implementation.
func (msg *MsgFilterClear) BtcDecode(r io.Reader, pver uint32, enc MessageEncoding) (e error) {
	if pver < BIP0037Version {
		str := fmt.Sprintf("filterclear message invalid for protocol "+
			"version %d", pver,
		)
		return messageError("MsgFilterClear.BtcDecode", str)
	}
	return nil
}

// BtcEncode encodes the receiver to w using the bitcoin protocol encoding. This is part of the Message interface
// implementation.
func (msg *MsgFilterClear) BtcEncode(w io.Writer, pver uint32, enc MessageEncoding) (e error) {
	if pver < BIP0037Version {
		str := fmt.Sprintf("filterclear message invalid for protocol "+
			"version %d", pver,
		)
		return messageError("MsgFilterClear.BtcEncode", str)
	}
	return nil
}

// Command returns the protocol command string for the message.  This is part of the Message interface implementation.
func (msg *MsgFilterClear) Command() string {
	return CmdFilterClear
}

// MaxPayloadLength returns the maximum length the payload can be for the receiver. This is part of the Message
// interface implementation.
func (msg *MsgFilterClear) MaxPayloadLength(pver uint32) uint32 {
	return 0
}

// NewMsgFilterClear returns a new bitcoin filterclear message that conforms to the Message interface. See
// MsgFilterClear for details.
func NewMsgFilterClear() *MsgFilterClear {
	return &MsgFilterClear{}
}