synapsecns/sanguine

package lightinbox

import (
    "fmt"

    "github.com/ethereum/go-ethereum/common"
    ethTypes "github.com/ethereum/go-ethereum/core/types"
    "github.com/synapsecns/sanguine/agents/types"
)

// Parser parses events from the light inbox contract.
type Parser interface {
    // EventType determines if an event was initiated by the bridge or the user.
    EventType(log ethTypes.Log) (_ EventType, ok bool)
    // ParseAttestationAccepted parses an AttestationAccepted event
    ParseAttestationAccepted(log ethTypes.Log) (_ *types.AttestationWithMetadata, err error)
}

type parserImpl struct {
    // filterer is the parser filterer we use to parse events
    filterer *LightInboxFilterer
}

// NewParser creates a new parser for the light inbox contract.
func NewParser(lightInboxAddress common.Address) (Parser, error) {
    parser, err := NewLightInboxFilterer(lightInboxAddress, nil)
    if err != nil {
        return nil, fmt.Errorf("could not create %T: %w", LightInboxFilterer{}, err)
    }

    return &parserImpl{filterer: parser}, nil
}

func (p parserImpl) EventType(log ethTypes.Log) (_ EventType, ok bool) {
    for _, logTopic := range log.Topics {
        eventType := eventTypeFromTopic(logTopic)
        if eventType == nil {
            continue
        }

        return *eventType, true
    }
    // return an unknown event to avoid cases where user failed to check the event type
    return EventType(len(topicMap()) + 2), false
}

// ParseAttestationAccepted parses an AttestationAccepted event.
func (p parserImpl) ParseAttestationAccepted(log ethTypes.Log) (_ *types.AttestationWithMetadata, err error) {
    lightInboxAttestationAccepted, err := p.filterer.ParseAttestationAccepted(log)
    if err != nil {
        return nil, fmt.Errorf("could not parse attestation accepted: %w", err)
    }

    attestationData, err := types.NewAttestationWithMetadata(
        lightInboxAttestationAccepted.AttPayload,
        lightInboxAttestationAccepted.Domain,
        lightInboxAttestationAccepted.Notary,
        lightInboxAttestationAccepted.AttSignature,
    )
    if err != nil {
        return nil, fmt.Errorf("could not create attestation with metadata from payload: %w", err)
    }

    return attestationData, nil
}

// EventType is the type of the light inbox event
//
//go:generate go run golang.org/x/tools/cmd/stringer -type=EventType
type EventType uint

const (
    // AttestationAcceptedEvent is an AttestationAccepted event.
    AttestationAcceptedEvent EventType = 0
)

// Int gets the int for an event type.
func (i EventType) Int() uint8 {
    return uint8(i)
}