From 53c04e09f8b7305a1b3f5589d20d5ccbf4f0579d Mon Sep 17 00:00:00 2001
From: Viacheslav Gonkivskyi <viacheslavgonkivskyi@gmail.com>
Date: Tue, 4 Jun 2024 16:04:54 +0300
Subject: [PATCH] feat: add tx options struct

---
 state/tx_options.go | 159 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 159 insertions(+)
 create mode 100644 state/tx_options.go

diff --git a/state/tx_options.go b/state/tx_options.go
new file mode 100644
index 0000000000..28568e9aad
--- /dev/null
+++ b/state/tx_options.go
@@ -0,0 +1,159 @@
+package state
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"math"
+
+	"github.com/celestiaorg/celestia-app/app"
+	sdktypes "github.com/cosmos/cosmos-sdk/types"
+
+	"github.com/celestiaorg/celestia-app/pkg/user"
+	apptypes "github.com/celestiaorg/celestia-app/x/blob/types"
+)
+
+// gasMultiplier is used to increase gas limit in case if tx has additional options.
+const gasMultiplier = 1.1
+
+var ErrNoGasProvided = errors.New("gas limit was not set")
+
+// TxOptions specifies additional options that will be applied to the Tx.
+type TxOptions struct {
+	fee      *Fee
+	GasLimit uint64
+
+	// Specifies the key that should be used to sign transactions.
+	// NOTE: This `Account` should be available in the `Keystore`.
+	Account string
+}
+
+func DefaultTxOptions() TxOptions {
+	return TxOptions{
+		fee:      DefaultFee(),
+		GasLimit: 0,
+		Account:  "",
+	}
+}
+
+type jsonTxOptions struct {
+	Fee      *Fee   `json:"fee"`
+	GasLimit uint64 `json:"gasLimit"`
+	Account  string `json:"account, omitempty"`
+}
+
+func (options *TxOptions) UnmarshalJSON(data []byte) error {
+	var jsonOpts *jsonTxOptions
+	err := json.Unmarshal(data, jsonOpts)
+	if err != nil {
+		return fmt.Errorf("unmarshalling TxOptions:%w", err)
+	}
+
+	options.fee.Amount = jsonOpts.Fee.Amount
+	options.fee.isSet = jsonOpts.Fee.isSet
+	options.GasLimit = jsonOpts.GasLimit
+	options.Account = jsonOpts.Account
+	return nil
+}
+
+// SetFeeAmount sets fee for the transaction.
+func (options *TxOptions) SetFeeAmount(amount int64) {
+	if amount >= 0 {
+		options.fee.Amount = amount
+		options.fee.isSet = true
+	}
+}
+
+// getFee returns fee amount as a `user.TxOption` that can be applied to the transactions.
+// It will calculate fee in case user haven't provided it.
+// NOTE: it is very important to ensure that gas limit was set.
+func (options *TxOptions) getFee(minGasPrice float64) (user.TxOption, error) {
+	if options.GasLimit == 0 {
+		return nil, ErrNoGasProvided
+	}
+
+	if !options.fee.isSet {
+		options.fee.Amount = int64(math.Ceil(minGasPrice * float64(options.GasLimit)))
+	}
+
+	fee := sdktypes.NewCoins(sdktypes.NewCoin(app.BondDenom, sdktypes.NewInt(options.fee.Amount)))
+	return user.SetFeeAmount(fee), nil
+}
+
+// getGas returns a gas limit as a `user.TxOption` that can be applied to the transactions.
+// GasLimit will be estimated in case it has not been set.
+// NOTE: final result of the estimation will be multiplied by the `gasMultiplier`(1.1) to cover additional options of the Tx,
+// as not all options are counted in the `EstimateGas`
+func (options *TxOptions) getGas(ctx context.Context, client *user.TxClient, msg sdktypes.Msg, opts ...user.TxOption) (user.TxOption, error) {
+	if options.GasLimit == 0 {
+		// Gas estimation depends on the amount of bytes of the original TX, including all options(Fee, Granter, etc.),
+		// so, it is very important to pass ALL options that will be applied to the tx.
+		// 1utia as fee is ok at this point(as fee may not be calculated yet).
+		opts = append([]user.TxOption{user.SetFee(1)}, opts...)
+		gasLimit, err := client.EstimateGas(ctx, []sdktypes.Msg{msg}, opts...)
+		if err != nil {
+			return nil, fmt.Errorf("estimating gas: %w", err)
+		}
+		options.GasLimit = uint64(float64(gasLimit) * gasMultiplier)
+	}
+	return user.SetGasLimit(options.GasLimit), nil
+}
+
+// getGasForBlobs returns a gas limit as a `user.TxOption` that can be applied to the `MsgPayForBlob` transactions.
+// NOTE: final result of the estimation will be multiplied by the `gasMultiplier`(1.1) to cover additional options of the Tx.
+func (options *TxOptions) getGasForBlobs(blobSizes []uint32) user.TxOption {
+	if options.GasLimit != 0 {
+		gasLimit := apptypes.DefaultEstimateGas(blobSizes)
+		options.GasLimit = uint64(float64(gasLimit) * gasMultiplier)
+	}
+	return user.SetGasLimit(options.GasLimit)
+}
+
+type Fee struct {
+	Amount int64
+	isSet  bool
+}
+
+func DefaultFee() *Fee {
+	return &Fee{
+		Amount: -1,
+	}
+}
+
+type jsonFee struct {
+	Amount int64 `json:"amount,omitempty"`
+	IsSet  bool  `json:"isSet,omitempty"`
+}
+
+func (f *Fee) MarshalJSON() ([]byte, error) {
+	fee := jsonFee{
+		Amount: f.Amount,
+		IsSet:  f.isSet,
+	}
+	return json.Marshal(fee)
+}
+
+func (f *Fee) UnmarshalJSON(data []byte) error {
+	var fee *jsonFee
+	err := json.Unmarshal(data, fee)
+	if err != nil {
+		return err
+	}
+
+	f.Amount = fee.Amount
+	f.isSet = fee.IsSet
+	if !f.isSet {
+		f.Amount = -1
+	}
+	return nil
+}
+
+func parseAddressFromString(addrStr string) (Address, error) {
+	var address Address
+	err := address.UnmarshalJSON([]byte(addrStr))
+	if err != nil {
+		return address, err
+	}
+	return address, nil
+}