package common

import (
	"encoding/json"

	"github.com/waku-org/go-waku/waku/v2/protocol/pb"
)

// Envelope contains information about the pubsub topic of a WakuMessage
// and a hash used to identify a message based on the bytes of a WakuMessage
// protobuffer
type Envelope struct {
	msg   *pb.WakuMessage
	topic string
	hash  MessageHash
}

type wakuMessage struct {
	Payload        []byte  `json:"payload,omitempty"`
	ContentTopic   string  `json:"contentTopic,omitempty"`
	Version        *uint32 `json:"version,omitempty"`
	Timestamp      *int64  `json:"timestamp,omitempty"`
	Meta           []byte  `json:"meta,omitempty"`
	Ephemeral      *bool   `json:"ephemeral,omitempty"`
	RateLimitProof []byte  `json:"proof,omitempty"`
}

type wakuEnvelope struct {
	WakuMessage wakuMessage `json:"wakuMessage"`
	PubsubTopic string      `json:"pubsubTopic"`
	MessageHash MessageHash `json:"messageHash"`
}

// NewEnvelope creates a new Envelope from a json string generated in nwaku
func NewEnvelope(jsonEventStr string) (*Envelope, error) {
	wakuEnvelope := wakuEnvelope{}
	err := json.Unmarshal([]byte(jsonEventStr), &wakuEnvelope)
	if err != nil {
		return nil, err
	}

	return &Envelope{
		msg: &pb.WakuMessage{
			Payload:        wakuEnvelope.WakuMessage.Payload,
			ContentTopic:   wakuEnvelope.WakuMessage.ContentTopic,
			Version:        wakuEnvelope.WakuMessage.Version,
			Timestamp:      wakuEnvelope.WakuMessage.Timestamp,
			Meta:           wakuEnvelope.WakuMessage.Meta,
			Ephemeral:      wakuEnvelope.WakuMessage.Ephemeral,
			RateLimitProof: wakuEnvelope.WakuMessage.RateLimitProof,
		},
		topic: wakuEnvelope.PubsubTopic,
		hash:  wakuEnvelope.MessageHash,
	}, nil
}

func (e *Envelope) Message() *pb.WakuMessage {
	return e.msg
}

func (e *Envelope) PubsubTopic() string {
	return e.topic
}

func (e *Envelope) Hash() MessageHash {
	return e.hash
}