rpc: use state.AppExecResult for ApplicationLog marshalling

Closes #1371

pkg/core/state/notification_event.go

@@ -1,7 +1,9 @@
 package state
 
 import (
+	"encoding/json"
 	"errors"
+	"fmt"
 
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
@@ -13,9 +15,9 @@ import (
 // NotificationEvent is a tuple of scripthash that emitted the Item as a
 // notification and that item itself.
 type NotificationEvent struct {
-	ScriptHash util.Uint160
-	Name       string
-	Item       *stackitem.Array
+	ScriptHash util.Uint160     `json:"contract"`
+	Name       string           `json:"eventname"`
+	Item       *stackitem.Array `json:"state"`
 }
 
 // AppExecResult represent the result of the script execution, gathering together
@@ -79,3 +81,119 @@ func (aer *AppExecResult) DecodeBinary(r *io.BinReader) {
 	}
 	r.ReadArray(&aer.Events)
 }
+
+// notificationEventAux is an auxiliary struct for NotificationEvent JSON marshalling.
+type notificationEventAux struct {
+	ScriptHash util.Uint160    `json:"contract"`
+	Name       string          `json:"eventname"`
+	Item       json.RawMessage `json:"state"`
+}
+
+// MarshalJSON implements implements json.Marshaler interface.
+func (ne *NotificationEvent) MarshalJSON() ([]byte, error) {
+	item, err := stackitem.ToJSONWithTypes(ne.Item)
+	if err != nil {
+		item = []byte(`"error: recursive reference"`)
+	}
+	return json.Marshal(&notificationEventAux{
+		ScriptHash: ne.ScriptHash,
+		Name:       ne.Name,
+		Item:       item,
+	})
+}
+
+// UnmarshalJSON implements json.Unmarshaler interface.
+func (ne *NotificationEvent) UnmarshalJSON(data []byte) error {
+	aux := new(notificationEventAux)
+	if err := json.Unmarshal(data, aux); err != nil {
+		return err
+	}
+	item, err := stackitem.FromJSONWithTypes(aux.Item)
+	if err != nil {
+		return err
+	}
+	if t := item.Type(); t != stackitem.ArrayT {
+		return fmt.Errorf("failed to convert notification event state of type %s to array", t.String())
+	}
+	ne.Item = item.(*stackitem.Array)
+	ne.Name = aux.Name
+	ne.ScriptHash = aux.ScriptHash
+	return nil
+}
+
+// appExecResultAux is an auxiliary struct for JSON marshalling
+type appExecResultAux struct {
+	TxHash      util.Uint256        `json:"txid"`
+	Trigger     string              `json:"trigger"`
+	VMState     string              `json:"vmstate"`
+	GasConsumed int64               `json:"gasconsumed,string"`
+	Stack       json.RawMessage     `json:"stack"`
+	Events      []NotificationEvent `json:"notifications"`
+}
+
+// MarshalJSON implements implements json.Marshaler interface.
+func (aer *AppExecResult) MarshalJSON() ([]byte, error) {
+	var st json.RawMessage
+	arr := make([]json.RawMessage, len(aer.Stack))
+	for i := range arr {
+		data, err := stackitem.ToJSONWithTypes(aer.Stack[i])
+		if err != nil {
+			st = []byte(`"error: recursive reference"`)
+			break
+		}
+		arr[i] = data
+	}
+
+	var err error
+	if st == nil {
+		st, err = json.Marshal(arr)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return json.Marshal(&appExecResultAux{
+		TxHash:      aer.TxHash,
+		Trigger:     aer.Trigger.String(),
+		VMState:     aer.VMState.String(),
+		GasConsumed: aer.GasConsumed,
+		Stack:       st,
+		Events:      aer.Events,
+	})
+}
+
+// UnmarshalJSON implements implements json.Unmarshaler interface.
+func (aer *AppExecResult) UnmarshalJSON(data []byte) error {
+	aux := new(appExecResultAux)
+	if err := json.Unmarshal(data, aux); err != nil {
+		return err
+	}
+	var arr []json.RawMessage
+	if err := json.Unmarshal(aux.Stack, &arr); err == nil {
+		st := make([]stackitem.Item, len(arr))
+		for i := range arr {
+			st[i], err = stackitem.FromJSONWithTypes(arr[i])
+			if err != nil {
+				break
+			}
+		}
+		if err == nil {
+			aer.Stack = st
+		}
+	}
+
+	trigger, err := trigger.FromString(aux.Trigger)
+	if err != nil {
+		return err
+	}
+	aer.Trigger = trigger
+	aer.TxHash = aux.TxHash
+	state, err := vm.StateFromString(aux.VMState)
+	if err != nil {
+		return err
+	}
+	aer.VMState = state
+	aer.Events = aux.Events
+	aer.GasConsumed = aux.GasConsumed
+
+	return nil
+}