frostfs-contract/rpcclient/container/client.go

// Package container contains RPC wrappers for Container contract.
//
// Code generated by neo-go contract generate-rpcwrapper --manifest <file.json> --out <file.go> [--hash <hash>] [--config <config>]; DO NOT EDIT.
package container

import (
	"crypto/elliptic"
	"errors"
	"fmt"
	"github.com/google/uuid"
	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
	"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
	"github.com/nspcc-dev/neo-go/pkg/rpcclient/unwrap"
	"github.com/nspcc-dev/neo-go/pkg/util"
	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
	"math/big"
)

// PutSuccessEvent represents "PutSuccess" event emitted by the contract.
type PutSuccessEvent struct {
	ContainerID util.Uint256
	PublicKey   *keys.PublicKey
}

// DeleteSuccessEvent represents "DeleteSuccess" event emitted by the contract.
type DeleteSuccessEvent struct {
	ContainerID []byte
}

// SetEACLSuccessEvent represents "SetEACLSuccess" event emitted by the contract.
type SetEACLSuccessEvent struct {
	ContainerID []byte
	PublicKey   *keys.PublicKey
}

// StartEstimationEvent represents "StartEstimation" event emitted by the contract.
type StartEstimationEvent struct {
	Epoch *big.Int
}

// StopEstimationEvent represents "StopEstimation" event emitted by the contract.
type StopEstimationEvent struct {
	Epoch *big.Int
}

// Invoker is used by ContractReader to call various safe methods.
type Invoker interface {
	Call(contract util.Uint160, operation string, params ...any) (*result.Invoke, error)
	CallAndExpandIterator(contract util.Uint160, method string, maxItems int, params ...any) (*result.Invoke, error)
	TerminateSession(sessionID uuid.UUID) error
	TraverseIterator(sessionID uuid.UUID, iterator *result.Iterator, num int) ([]stackitem.Item, error)
}

// Actor is used by Contract to call state-changing methods.
type Actor interface {
	Invoker

	MakeCall(contract util.Uint160, method string, params ...any) (*transaction.Transaction, error)
	MakeRun(script []byte) (*transaction.Transaction, error)
	MakeUnsignedCall(contract util.Uint160, method string, attrs []transaction.Attribute, params ...any) (*transaction.Transaction, error)
	MakeUnsignedRun(script []byte, attrs []transaction.Attribute) (*transaction.Transaction, error)
	SendCall(contract util.Uint160, method string, params ...any) (util.Uint256, uint32, error)
	SendRun(script []byte) (util.Uint256, uint32, error)
}

// ContractReader implements safe contract methods.
type ContractReader struct {
	invoker Invoker
	hash    util.Uint160
}

// Contract implements all contract methods.
type Contract struct {
	ContractReader
	actor Actor
	hash  util.Uint160
}

// NewReader creates an instance of ContractReader using provided contract hash and the given Invoker.
func NewReader(invoker Invoker, hash util.Uint160) *ContractReader {
	return &ContractReader{invoker, hash}
}

// New creates an instance of Contract using provided contract hash and the given Actor.
func New(actor Actor, hash util.Uint160) *Contract {
	return &Contract{ContractReader{actor, hash}, actor, hash}
}

// ContainersOf invokes `containersOf` method of contract.
func (c *ContractReader) ContainersOf(owner []byte) (uuid.UUID, result.Iterator, error) {
	return unwrap.SessionIterator(c.invoker.Call(c.hash, "containersOf", owner))
}

// ContainersOfExpanded is similar to ContainersOf (uses the same contract
// method), but can be useful if the server used doesn't support sessions and
// doesn't expand iterators. It creates a script that will get the specified
// number of result items from the iterator right in the VM and return them to
// you. It's only limited by VM stack and GAS available for RPC invocations.
func (c *ContractReader) ContainersOfExpanded(owner []byte, _numOfIteratorItems int) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.CallAndExpandIterator(c.hash, "containersOf", _numOfIteratorItems, owner))
}

// Count invokes `count` method of contract.
func (c *ContractReader) Count() (*big.Int, error) {
	return unwrap.BigInt(c.invoker.Call(c.hash, "count"))
}

// DeletionInfo invokes `deletionInfo` method of contract.
func (c *ContractReader) DeletionInfo(containerID []byte) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.Call(c.hash, "deletionInfo", containerID))
}

// EACL invokes `eACL` method of contract.
func (c *ContractReader) EACL(containerID []byte) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.Call(c.hash, "eACL", containerID))
}

// Get invokes `get` method of contract.
func (c *ContractReader) Get(containerID []byte) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.Call(c.hash, "get", containerID))
}

// GetContainerSize invokes `getContainerSize` method of contract.
func (c *ContractReader) GetContainerSize(id []byte) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.Call(c.hash, "getContainerSize", id))
}

// IterateContainerSizes invokes `iterateContainerSizes` method of contract.
func (c *ContractReader) IterateContainerSizes(epoch *big.Int) (uuid.UUID, result.Iterator, error) {
	return unwrap.SessionIterator(c.invoker.Call(c.hash, "iterateContainerSizes", epoch))
}

// IterateContainerSizesExpanded is similar to IterateContainerSizes (uses the same contract
// method), but can be useful if the server used doesn't support sessions and
// doesn't expand iterators. It creates a script that will get the specified
// number of result items from the iterator right in the VM and return them to
// you. It's only limited by VM stack and GAS available for RPC invocations.
func (c *ContractReader) IterateContainerSizesExpanded(epoch *big.Int, _numOfIteratorItems int) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.CallAndExpandIterator(c.hash, "iterateContainerSizes", _numOfIteratorItems, epoch))
}

// List invokes `list` method of contract.
func (c *ContractReader) List(owner []byte) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.Call(c.hash, "list", owner))
}

// ListContainerSizes invokes `listContainerSizes` method of contract.
func (c *ContractReader) ListContainerSizes(epoch *big.Int) ([]stackitem.Item, error) {
	return unwrap.Array(c.invoker.Call(c.hash, "listContainerSizes", epoch))
}

// Owner invokes `owner` method of contract.
func (c *ContractReader) Owner(containerID []byte) ([]byte, error) {
	return unwrap.Bytes(c.invoker.Call(c.hash, "owner", containerID))
}

// Version invokes `version` method of contract.
func (c *ContractReader) Version() (*big.Int, error) {
	return unwrap.BigInt(c.invoker.Call(c.hash, "version"))
}

// Delete creates a transaction invoking `delete` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) Delete(containerID []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "delete", containerID, signature, publicKey, token)
}

// DeleteTransaction creates a transaction invoking `delete` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) DeleteTransaction(containerID []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "delete", containerID, signature, publicKey, token)
}

// DeleteUnsigned creates a transaction invoking `delete` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) DeleteUnsigned(containerID []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "delete", nil, containerID, signature, publicKey, token)
}

// NewEpoch creates a transaction invoking `newEpoch` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) NewEpoch(epochNum *big.Int) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "newEpoch", epochNum)
}

// NewEpochTransaction creates a transaction invoking `newEpoch` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) NewEpochTransaction(epochNum *big.Int) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "newEpoch", epochNum)
}

// NewEpochUnsigned creates a transaction invoking `newEpoch` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) NewEpochUnsigned(epochNum *big.Int) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "newEpoch", nil, epochNum)
}

// Put creates a transaction invoking `put` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) Put(container []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "put", container, signature, publicKey, token)
}

// PutTransaction creates a transaction invoking `put` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) PutTransaction(container []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "put", container, signature, publicKey, token)
}

// PutUnsigned creates a transaction invoking `put` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) PutUnsigned(container []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "put", nil, container, signature, publicKey, token)
}

// PutContainerSize creates a transaction invoking `putContainerSize` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) PutContainerSize(epoch *big.Int, cid []byte, usedSize *big.Int, pubKey *keys.PublicKey) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "putContainerSize", epoch, cid, usedSize, pubKey)
}

// PutContainerSizeTransaction creates a transaction invoking `putContainerSize` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) PutContainerSizeTransaction(epoch *big.Int, cid []byte, usedSize *big.Int, pubKey *keys.PublicKey) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "putContainerSize", epoch, cid, usedSize, pubKey)
}

// PutContainerSizeUnsigned creates a transaction invoking `putContainerSize` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) PutContainerSizeUnsigned(epoch *big.Int, cid []byte, usedSize *big.Int, pubKey *keys.PublicKey) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "putContainerSize", nil, epoch, cid, usedSize, pubKey)
}

// PutNamed creates a transaction invoking `putNamed` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) PutNamed(container []byte, signature []byte, publicKey *keys.PublicKey, token []byte, name string, zone string) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "putNamed", container, signature, publicKey, token, name, zone)
}

// PutNamedTransaction creates a transaction invoking `putNamed` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) PutNamedTransaction(container []byte, signature []byte, publicKey *keys.PublicKey, token []byte, name string, zone string) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "putNamed", container, signature, publicKey, token, name, zone)
}

// PutNamedUnsigned creates a transaction invoking `putNamed` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) PutNamedUnsigned(container []byte, signature []byte, publicKey *keys.PublicKey, token []byte, name string, zone string) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "putNamed", nil, container, signature, publicKey, token, name, zone)
}

// SetEACL creates a transaction invoking `setEACL` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) SetEACL(eACL []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "setEACL", eACL, signature, publicKey, token)
}

// SetEACLTransaction creates a transaction invoking `setEACL` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) SetEACLTransaction(eACL []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "setEACL", eACL, signature, publicKey, token)
}

// SetEACLUnsigned creates a transaction invoking `setEACL` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) SetEACLUnsigned(eACL []byte, signature []byte, publicKey *keys.PublicKey, token []byte) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "setEACL", nil, eACL, signature, publicKey, token)
}

// StartContainerEstimation creates a transaction invoking `startContainerEstimation` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) StartContainerEstimation(epoch *big.Int) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "startContainerEstimation", epoch)
}

// StartContainerEstimationTransaction creates a transaction invoking `startContainerEstimation` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) StartContainerEstimationTransaction(epoch *big.Int) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "startContainerEstimation", epoch)
}

// StartContainerEstimationUnsigned creates a transaction invoking `startContainerEstimation` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) StartContainerEstimationUnsigned(epoch *big.Int) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "startContainerEstimation", nil, epoch)
}

// StopContainerEstimation creates a transaction invoking `stopContainerEstimation` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) StopContainerEstimation(epoch *big.Int) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "stopContainerEstimation", epoch)
}

// StopContainerEstimationTransaction creates a transaction invoking `stopContainerEstimation` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) StopContainerEstimationTransaction(epoch *big.Int) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "stopContainerEstimation", epoch)
}

// StopContainerEstimationUnsigned creates a transaction invoking `stopContainerEstimation` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) StopContainerEstimationUnsigned(epoch *big.Int) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "stopContainerEstimation", nil, epoch)
}

// Update creates a transaction invoking `update` method of the contract.
// This transaction is signed and immediately sent to the network.
// The values returned are its hash, ValidUntilBlock value and error if any.
func (c *Contract) Update(script []byte, manifest []byte, data any) (util.Uint256, uint32, error) {
	return c.actor.SendCall(c.hash, "update", script, manifest, data)
}

// UpdateTransaction creates a transaction invoking `update` method of the contract.
// This transaction is signed, but not sent to the network, instead it's
// returned to the caller.
func (c *Contract) UpdateTransaction(script []byte, manifest []byte, data any) (*transaction.Transaction, error) {
	return c.actor.MakeCall(c.hash, "update", script, manifest, data)
}

// UpdateUnsigned creates a transaction invoking `update` method of the contract.
// This transaction is not signed, it's simply returned to the caller.
// Any fields of it that do not affect fees can be changed (ValidUntilBlock,
// Nonce), fee values (NetworkFee, SystemFee) can be increased as well.
func (c *Contract) UpdateUnsigned(script []byte, manifest []byte, data any) (*transaction.Transaction, error) {
	return c.actor.MakeUnsignedCall(c.hash, "update", nil, script, manifest, data)
}

// PutSuccessEventsFromApplicationLog retrieves a set of all emitted events
// with "PutSuccess" name from the provided [result.ApplicationLog].
func PutSuccessEventsFromApplicationLog(log *result.ApplicationLog) ([]*PutSuccessEvent, error) {
	if log == nil {
		return nil, errors.New("nil application log")
	}

	var res []*PutSuccessEvent
	for i, ex := range log.Executions {
		for j, e := range ex.Events {
			if e.Name != "PutSuccess" {
				continue
			}
			event := new(PutSuccessEvent)
			err := event.FromStackItem(e.Item)
			if err != nil {
				return nil, fmt.Errorf("failed to deserialize PutSuccessEvent from stackitem (execution #%d, event #%d): %w", i, j, err)
			}
			res = append(res, event)
		}
	}

	return res, nil
}

// FromStackItem converts provided [stackitem.Array] to PutSuccessEvent or
// returns an error if it's not possible to do to so.
func (e *PutSuccessEvent) FromStackItem(item *stackitem.Array) error {
	if item == nil {
		return errors.New("nil item")
	}
	arr, ok := item.Value().([]stackitem.Item)
	if !ok {
		return errors.New("not an array")
	}
	if len(arr) != 2 {
		return errors.New("wrong number of structure elements")
	}

	var (
		index = -1
		err   error
	)
	index++
	e.ContainerID, err = func(item stackitem.Item) (util.Uint256, error) {
		b, err := item.TryBytes()
		if err != nil {
			return util.Uint256{}, err
		}
		u, err := util.Uint256DecodeBytesBE(b)
		if err != nil {
			return util.Uint256{}, err
		}
		return u, nil
	}(arr[index])
	if err != nil {
		return fmt.Errorf("field ContainerID: %w", err)
	}

	index++
	e.PublicKey, err = func(item stackitem.Item) (*keys.PublicKey, error) {
		b, err := item.TryBytes()
		if err != nil {
			return nil, err
		}
		k, err := keys.NewPublicKeyFromBytes(b, elliptic.P256())
		if err != nil {
			return nil, err
		}
		return k, nil
	}(arr[index])
	if err != nil {
		return fmt.Errorf("field PublicKey: %w", err)
	}

	return nil
}

// DeleteSuccessEventsFromApplicationLog retrieves a set of all emitted events
// with "DeleteSuccess" name from the provided [result.ApplicationLog].
func DeleteSuccessEventsFromApplicationLog(log *result.ApplicationLog) ([]*DeleteSuccessEvent, error) {
	if log == nil {
		return nil, errors.New("nil application log")
	}

	var res []*DeleteSuccessEvent
	for i, ex := range log.Executions {
		for j, e := range ex.Events {
			if e.Name != "DeleteSuccess" {
				continue
			}
			event := new(DeleteSuccessEvent)
			err := event.FromStackItem(e.Item)
			if err != nil {
				return nil, fmt.Errorf("failed to deserialize DeleteSuccessEvent from stackitem (execution #%d, event #%d): %w", i, j, err)
			}
			res = append(res, event)
		}
	}

	return res, nil
}

// FromStackItem converts provided [stackitem.Array] to DeleteSuccessEvent or
// returns an error if it's not possible to do to so.
func (e *DeleteSuccessEvent) FromStackItem(item *stackitem.Array) error {
	if item == nil {
		return errors.New("nil item")
	}
	arr, ok := item.Value().([]stackitem.Item)
	if !ok {
		return errors.New("not an array")
	}
	if len(arr) != 1 {
		return errors.New("wrong number of structure elements")
	}

	var (
		index = -1
		err   error
	)
	index++
	e.ContainerID, err = arr[index].TryBytes()
	if err != nil {
		return fmt.Errorf("field ContainerID: %w", err)
	}

	return nil
}

// SetEACLSuccessEventsFromApplicationLog retrieves a set of all emitted events
// with "SetEACLSuccess" name from the provided [result.ApplicationLog].
func SetEACLSuccessEventsFromApplicationLog(log *result.ApplicationLog) ([]*SetEACLSuccessEvent, error) {
	if log == nil {
		return nil, errors.New("nil application log")
	}

	var res []*SetEACLSuccessEvent
	for i, ex := range log.Executions {
		for j, e := range ex.Events {
			if e.Name != "SetEACLSuccess" {
				continue
			}
			event := new(SetEACLSuccessEvent)
			err := event.FromStackItem(e.Item)
			if err != nil {
				return nil, fmt.Errorf("failed to deserialize SetEACLSuccessEvent from stackitem (execution #%d, event #%d): %w", i, j, err)
			}
			res = append(res, event)
		}
	}

	return res, nil
}

// FromStackItem converts provided [stackitem.Array] to SetEACLSuccessEvent or
// returns an error if it's not possible to do to so.
func (e *SetEACLSuccessEvent) FromStackItem(item *stackitem.Array) error {
	if item == nil {
		return errors.New("nil item")
	}
	arr, ok := item.Value().([]stackitem.Item)
	if !ok {
		return errors.New("not an array")
	}
	if len(arr) != 2 {
		return errors.New("wrong number of structure elements")
	}

	var (
		index = -1
		err   error
	)
	index++
	e.ContainerID, err = arr[index].TryBytes()
	if err != nil {
		return fmt.Errorf("field ContainerID: %w", err)
	}

	index++
	e.PublicKey, err = func(item stackitem.Item) (*keys.PublicKey, error) {
		b, err := item.TryBytes()
		if err != nil {
			return nil, err
		}
		k, err := keys.NewPublicKeyFromBytes(b, elliptic.P256())
		if err != nil {
			return nil, err
		}
		return k, nil
	}(arr[index])
	if err != nil {
		return fmt.Errorf("field PublicKey: %w", err)
	}

	return nil
}

// StartEstimationEventsFromApplicationLog retrieves a set of all emitted events
// with "StartEstimation" name from the provided [result.ApplicationLog].
func StartEstimationEventsFromApplicationLog(log *result.ApplicationLog) ([]*StartEstimationEvent, error) {
	if log == nil {
		return nil, errors.New("nil application log")
	}

	var res []*StartEstimationEvent
	for i, ex := range log.Executions {
		for j, e := range ex.Events {
			if e.Name != "StartEstimation" {
				continue
			}
			event := new(StartEstimationEvent)
			err := event.FromStackItem(e.Item)
			if err != nil {
				return nil, fmt.Errorf("failed to deserialize StartEstimationEvent from stackitem (execution #%d, event #%d): %w", i, j, err)
			}
			res = append(res, event)
		}
	}

	return res, nil
}

// FromStackItem converts provided [stackitem.Array] to StartEstimationEvent or
// returns an error if it's not possible to do to so.
func (e *StartEstimationEvent) FromStackItem(item *stackitem.Array) error {
	if item == nil {
		return errors.New("nil item")
	}
	arr, ok := item.Value().([]stackitem.Item)
	if !ok {
		return errors.New("not an array")
	}
	if len(arr) != 1 {
		return errors.New("wrong number of structure elements")
	}

	var (
		index = -1
		err   error
	)
	index++
	e.Epoch, err = arr[index].TryInteger()
	if err != nil {
		return fmt.Errorf("field Epoch: %w", err)
	}

	return nil
}

// StopEstimationEventsFromApplicationLog retrieves a set of all emitted events
// with "StopEstimation" name from the provided [result.ApplicationLog].
func StopEstimationEventsFromApplicationLog(log *result.ApplicationLog) ([]*StopEstimationEvent, error) {
	if log == nil {
		return nil, errors.New("nil application log")
	}

	var res []*StopEstimationEvent
	for i, ex := range log.Executions {
		for j, e := range ex.Events {
			if e.Name != "StopEstimation" {
				continue
			}
			event := new(StopEstimationEvent)
			err := event.FromStackItem(e.Item)
			if err != nil {
				return nil, fmt.Errorf("failed to deserialize StopEstimationEvent from stackitem (execution #%d, event #%d): %w", i, j, err)
			}
			res = append(res, event)
		}
	}

	return res, nil
}

// FromStackItem converts provided [stackitem.Array] to StopEstimationEvent or
// returns an error if it's not possible to do to so.
func (e *StopEstimationEvent) FromStackItem(item *stackitem.Array) error {
	if item == nil {
		return errors.New("nil item")
	}
	arr, ok := item.Value().([]stackitem.Item)
	if !ok {
		return errors.New("not an array")
	}
	if len(arr) != 1 {
		return errors.New("wrong number of structure elements")
	}

	var (
		index = -1
		err   error
	)
	index++
	e.Epoch, err = arr[index].TryInteger()
	if err != nil {
		return fmt.Errorf("field Epoch: %w", err)
	}

	return nil
}