package frame

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

type Tag uint32

// 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      Tag
	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 {
	tag := coder.NewPrimitivePacketEncoder(byte(TagOfPayloadDataTag))
	tag.SetUInt32Value(uint32(m.Tag))

	carriage := coder.NewPrimitivePacketEncoder(byte(TagOfPayloadCarriage))
	carriage.SetBytesValue(m.Carriage)

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

	return payload.Encode()
}

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

	if p, ok := nodeBlock.PrimitivePackets[byte(TagOfPayloadDataTag)]; ok {
		tag, err := p.ToUInt32()
		if err != nil {
			return err
		}
		payload.Tag = Tag(tag)
	}

	if p, ok := nodeBlock.PrimitivePackets[byte(TagOfPayloadCarriage)]; ok {
		payload.Carriage = p.GetValBuf()
	}

	return nil
}