package frame

import (
	coder "git.hpds.cc/Component/mq_coder"
)

// PayloadFrame is a coder encoded bytes, Tag is a fixed value TYPE_ID_PAYLOAD_FRAME
// the Len is the length of Val. Val is also a coder encoded PrimitivePacket, storing
// raw bytes as user's data
type PayloadFrame struct {
	Tag      byte
	Carriage []byte
}

// NewPayloadFrame creates a new PayloadFrame with a given TagId of user's data
func NewPayloadFrame(tag byte) *PayloadFrame {
	return &PayloadFrame{
		Tag: tag,
	}
}

// SetCarriage sets the user's raw data
func (m *PayloadFrame) SetCarriage(buf []byte) *PayloadFrame {
	m.Carriage = buf
	return m
}

// Encode to coder encoded bytes
func (m *PayloadFrame) Encode() []byte {
	carriage := coder.NewPrimitivePacketEncoder(m.Tag)
	carriage.SetBytesValue(m.Carriage)

	payload := coder.NewNodePacketEncoder(TagOfPayloadFrame)
	payload.AddPrimitivePacket(carriage)

	return payload.Encode()
}

// DecodeToPayloadFrame decodes coder encoded bytes to PayloadFrame
func DecodeToPayloadFrame(buf []byte) (*PayloadFrame, error) {
	nodeBlock := coder.NodePacket{}
	_, err := coder.DecodeToNodePacket(buf, &nodeBlock)
	if err != nil {
		return nil, err
	}

	payload := &PayloadFrame{}
	for _, v := range nodeBlock.PrimitivePackets {
		payload.Tag = v.SeqId()
		payload.Carriage = v.GetValBuf()
		break
	}

	return payload, nil
}