[#1545] morph/event: Simplify frostfs contract event parsing

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

pkg/morph/event/frostfs/cheque.go

@@ -3,7 +3,7 @@ package frostfs
 import (
 	"fmt"
 
-	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/morph/client"
+	"git.frostfs.info/TrueCloudLab/frostfs-contract/rpcclient/frostfs"
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/morph/event"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/util"
@@ -34,53 +34,20 @@ func (c Cheque) LockAccount() util.Uint160 { return c.LockValue }
 
 // ParseCheque from notification into cheque structure.
 func ParseCheque(e *state.ContainedNotificationEvent) (event.Event, error) {
-	var (
-		ev  Cheque
-		err error
-	)
+	var ce frostfs.ChequeEvent
+	if err := ce.FromStackItem(e.Item); err != nil {
+		return nil, fmt.Errorf("parse frostfs.ChequeEvent: %w", err)
+	}
 
-	params, err := event.ParseStackArray(e)
+	lock, err := util.Uint160DecodeBytesBE(ce.LockAccount)
 	if err != nil {
-		return nil, fmt.Errorf("could not parse stack items from notify event: %w", err)
+		return nil, fmt.Errorf("parse frostfs.ChequeEvent: field LockAccount: %w", err)
 	}
 
-	if ln := len(params); ln != 4 {
-		return nil, event.WrongNumberOfParameters(4, ln)
-	}
-
-	// parse id
-	ev.IDValue, err = client.BytesFromStackItem(params[0])
-	if err != nil {
-		return nil, fmt.Errorf("could not get cheque id: %w", err)
-	}
-
-	// parse user
-	user, err := client.BytesFromStackItem(params[1])
-	if err != nil {
-		return nil, fmt.Errorf("could not get cheque user: %w", err)
-	}
-
-	ev.UserValue, err = util.Uint160DecodeBytesBE(user)
-	if err != nil {
-		return nil, fmt.Errorf("could not convert cheque user to uint160: %w", err)
-	}
-
-	// parse amount
-	ev.AmountValue, err = client.IntFromStackItem(params[2])
-	if err != nil {
-		return nil, fmt.Errorf("could not get cheque amount: %w", err)
-	}
-
-	// parse lock account
-	lock, err := client.BytesFromStackItem(params[3])
-	if err != nil {
-		return nil, fmt.Errorf("could not get cheque lock account: %w", err)
-	}
-
-	ev.LockValue, err = util.Uint160DecodeBytesBE(lock)
-	if err != nil {
-		return nil, fmt.Errorf("could not convert cheque lock account to uint160: %w", err)
-	}
-
-	return ev, nil
+	return Cheque{
+		IDValue:     ce.Id,
+		AmountValue: ce.Amount.Int64(),
+		UserValue:   ce.User,
+		LockValue:   lock,
+	}, nil
 }