From 55645478594858a6830e4ab095034068ef9753e9 Mon Sep 17 00:00:00 2001
From: Quinn Hou <quinn.hou@dapperlabs.com>
Date: Mon, 18 Oct 2021 11:58:27 -0700
Subject: [PATCH] Add revealed event (#129)

---
 lib/go/events/revealed.go      | 59 +++++++++++++++++++++++++++++++++
 lib/go/events/revealed_test.go | 60 ++++++++++++++++++++++++++++++++++
 2 files changed, 119 insertions(+)
 create mode 100644 lib/go/events/revealed.go
 create mode 100644 lib/go/events/revealed_test.go

diff --git a/lib/go/events/revealed.go b/lib/go/events/revealed.go
new file mode 100644
index 00000000..f27dacf7
--- /dev/null
+++ b/lib/go/events/revealed.go
@@ -0,0 +1,59 @@
+package events
+
+import (
+	"fmt"
+	"github.com/onflow/cadence"
+	jsoncdc "github.com/onflow/cadence/encoding/json"
+	"strings"
+)
+
+const (
+	// EventRevealed specifies that there is a Revealed Event on a PackNFT Contract located at the address
+	EventRevealed = "PackNFT.Revealed"
+)
+
+type RevealedEvent interface {
+	Id() uint64
+	Salt() string
+	NFTs() string
+}
+
+type revealedEvent cadence.Event
+
+var _ RevealedEvent = (*revealedEvent)(nil)
+
+func (evt revealedEvent) Id() uint64 {
+	return uint64(evt.Fields[0].(cadence.UInt64))
+}
+
+func (evt revealedEvent) Salt() string {
+	return string(evt.Fields[1].(cadence.String))
+}
+
+func (evt revealedEvent) NFTs() string {
+	return string(evt.Fields[2].(cadence.String))
+}
+
+func (evt revealedEvent) validate() error {
+	if evt.EventType.QualifiedIdentifier != EventRevealed {
+		return fmt.Errorf("error validating event: event is not a valid revealed event, expected type %s, got %s",
+			EventRevealed, evt.EventType.QualifiedIdentifier)
+	}
+	return nil
+}
+
+func parseNFTs(nft string) []string {
+	return strings.Split(nft, ",")
+}
+
+func DecodeRevealedEvent(b []byte) (RevealedEvent, error) {
+	value, err := jsoncdc.Decode(b)
+	if err != nil {
+		return nil, err
+	}
+	event := revealedEvent(value.(cadence.Event))
+	if err := event.validate(); err != nil {
+		return nil, fmt.Errorf("error decoding event: %w", err)
+	}
+	return event, nil
+}
\ No newline at end of file
diff --git a/lib/go/events/revealed_test.go b/lib/go/events/revealed_test.go
new file mode 100644
index 00000000..9e87dba8
--- /dev/null
+++ b/lib/go/events/revealed_test.go
@@ -0,0 +1,60 @@
+package events
+
+import (
+	"fmt"
+	"github.com/stretchr/testify/require"
+	"testing"
+
+	"github.com/onflow/cadence"
+	jsoncdc "github.com/onflow/cadence/encoding/json"
+	"github.com/onflow/cadence/runtime/tests/utils"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCadenceEvents_Reveal(t *testing.T) {
+	var (
+		packID = uint64(10)
+		salt = "salt"
+
+		momentID1 = uint64(1)
+		momentID2 = uint64(2)
+		momentID3 = uint64(3)
+		momentIDs = fmt.Sprintf(`%d,%d,%d`, momentID1, momentID2, momentID3)
+	)
+
+	revealedEventType := cadence.EventType{
+		Location:            utils.TestLocation,
+		QualifiedIdentifier: "PackNFT.Revealed",
+		Fields: []cadence.Field{
+			{
+				Identifier: "id",
+				Type:       cadence.UInt32Type{},
+			},
+			{
+				Identifier: "salt",
+				Type:       cadence.StringType{},
+			},
+			{
+				Identifier: "nfts",
+				Type:       cadence.StringType{},
+			},
+		},
+	}
+
+	revealedEvent := cadence.NewEvent([]cadence.Value{
+		cadence.NewUInt64(packID),
+		cadence.NewString(salt),
+		cadence.NewString(momentIDs),
+	}).WithType(&revealedEventType)
+
+	revealedPayload, err := jsoncdc.Encode(revealedEvent)
+	require.NoError(t, err, "failed to encode revealed cadence event")
+
+	decodedRevealedEventType, err := DecodeRevealedEvent(revealedPayload)
+	require.NoError(t, err, "failed to decode revealed cadence event")
+
+	assert.Equal(t, packID, decodedRevealedEventType.Id())
+	assert.Equal(t, salt, decodedRevealedEventType.Salt())
+	assert.Equal(t, momentIDs, decodedRevealedEventType.NFTs())
+
+}