From e9695baebbfa44279677326182a4d8baeb2c3c2f Mon Sep 17 00:00:00 2001
From: Ethan Buchman <ethan@coinculture.info>
Date: Wed, 20 May 2015 20:02:59 -0400
Subject: [PATCH] tx utils

---
 state/execution.go |   1 +
 types/tx_utils.go  | 145 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 146 insertions(+)
 create mode 100644 types/tx_utils.go

diff --git a/state/execution.go b/state/execution.go
index 870d463a1..9b6c35be7 100644
--- a/state/execution.go
+++ b/state/execution.go
@@ -489,6 +489,7 @@ func ExecTx(blockCache *BlockCache, tx_ types.Tx, runCall bool, evc events.Firea
 		if err != nil {
 			return err
 		}
+
 		signBytes := account.SignBytes(tx)
 		inTotal, err := validateInputs(accounts, signBytes, tx.Inputs)
 		if err != nil {
diff --git a/types/tx_utils.go b/types/tx_utils.go
new file mode 100644
index 000000000..b307c88b4
--- /dev/null
+++ b/types/tx_utils.go
@@ -0,0 +1,145 @@
+package types
+
+import (
+	"fmt"
+	"github.com/tendermint/tendermint/account"
+)
+
+type AccountGetter interface {
+	GetAccount(addr []byte) *account.Account
+}
+
+//----------------------------------------------------------------------------
+// SendTx interface for adding inputs/outputs and adding signatures
+
+func NewSendTx() *SendTx {
+	return &SendTx{
+		Inputs:  []*TxInput{},
+		Outputs: []*TxOutput{},
+	}
+}
+
+func (tx *SendTx) AddInput(st AccountGetter, pubkey account.PubKey, amt uint64) error {
+	addr := pubkey.Address()
+	acc := st.GetAccount(addr)
+	if acc == nil {
+		return fmt.Errorf("Invalid address %X from pubkey %X", addr, pubkey)
+	}
+
+	tx.Inputs = append(tx.Inputs, &TxInput{
+		Address:   addr,
+		Amount:    amt,
+		Sequence:  uint(acc.Sequence) + 1,
+		Signature: account.SignatureEd25519{},
+		PubKey:    pubkey,
+	})
+	return nil
+}
+
+func (tx *SendTx) AddOutput(addr []byte, amt uint64) error {
+	tx.Outputs = append(tx.Outputs, &TxOutput{
+		Address: addr,
+		Amount:  amt,
+	})
+	return nil
+}
+
+func (tx *SendTx) SignInput(i int, privAccount *account.PrivAccount) error {
+	if i >= len(tx.Inputs) {
+		return fmt.Errorf("Index %v is greater than number of inputs (%v)", i, len(tx.Inputs))
+	}
+	tx.Inputs[i].PubKey = privAccount.PubKey
+	tx.Inputs[i].Signature = privAccount.Sign(tx)
+	return nil
+}
+
+//----------------------------------------------------------------------------
+// CallTx interface for creating tx
+
+func NewCallTx(st AccountGetter, from account.PubKey, to, data []byte, amt, gasLimit, fee uint64) (*CallTx, error) {
+	addr := from.Address()
+	acc := st.GetAccount(addr)
+	if acc == nil {
+		return nil, fmt.Errorf("Invalid address %X from pubkey %X", addr, from)
+	}
+
+	input := &TxInput{
+		Address:   addr,
+		Amount:    amt,
+		Sequence:  uint(acc.Sequence) + 1,
+		Signature: account.SignatureEd25519{},
+		PubKey:    from,
+	}
+
+	return &CallTx{
+		Input:    input,
+		Address:  to,
+		GasLimit: gasLimit,
+		Fee:      fee,
+		Data:     data,
+	}, nil
+}
+
+func (tx *CallTx) Sign(privAccount *account.PrivAccount) {
+	tx.Input.PubKey = privAccount.PubKey
+	tx.Input.Signature = privAccount.Sign(tx)
+}
+
+//----------------------------------------------------------------------------
+// BondTx interface for adding inputs/outputs and adding signatures
+
+func NewBondTx(pubkey account.PubKey) (*BondTx, error) {
+	pubkeyEd, ok := pubkey.(account.PubKeyEd25519)
+	if !ok {
+		return nil, fmt.Errorf("Pubkey must be ed25519")
+	}
+	return &BondTx{
+		PubKey:   pubkeyEd,
+		Inputs:   []*TxInput{},
+		UnbondTo: []*TxOutput{},
+	}, nil
+}
+
+func (tx *BondTx) AddInput(st AccountGetter, pubkey account.PubKey, amt uint64) error {
+	addr := pubkey.Address()
+	acc := st.GetAccount(addr)
+	if acc == nil {
+		return fmt.Errorf("Invalid address %X from pubkey %X", addr, pubkey)
+	}
+
+	tx.Inputs = append(tx.Inputs, &TxInput{
+		Address:   addr,
+		Amount:    amt,
+		Sequence:  uint(acc.Sequence) + 1,
+		Signature: account.SignatureEd25519{},
+		PubKey:    pubkey,
+	})
+	return nil
+}
+
+func (tx *BondTx) AddOutput(addr []byte, amt uint64) error {
+	tx.UnbondTo = append(tx.UnbondTo, &TxOutput{
+		Address: addr,
+		Amount:  amt,
+	})
+	return nil
+}
+
+func (tx *BondTx) SignBond(privAccount *account.PrivAccount) error {
+	sig := privAccount.Sign(tx)
+	sigEd, ok := sig.(account.SignatureEd25519)
+	if !ok {
+		return fmt.Errorf("Bond signer must be ED25519")
+	}
+	tx.Signature = sigEd
+	return nil
+}
+
+func (tx *BondTx) SignInput(i int, privAccount *account.PrivAccount) error {
+	if i >= len(tx.Inputs) {
+		return fmt.Errorf("Index %v is greater than number of inputs (%v)", i, len(tx.Inputs))
+	}
+	tx.Inputs[i].PubKey = privAccount.PubKey
+	tx.Inputs[i].Signature = privAccount.Sign(tx)
+	return nil
+}