1 files changed, 110 insertions, 0 deletions
diff --git a/eth/bind.go b/eth/bind.go
new file mode 100644
index 000000000..3a3eca062
--- /dev/null
+++ b/eth/bind.go
@@ -0,0 +1,110 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package eth
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/accounts/abi/bind"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/ethereum/go-ethereum/rpc"
+)
+
+// ContractBackend implements bind.ContractBackend with direct calls to Ethereum
+// internals to support operating on contracts within subprotocols like eth and
+// swarm.
+//
+// Internally this backend uses the already exposed API endpoints of the Ethereum
+// object. These should be rewritten to internal Go method calls when the Go API
+// is refactored to support a clean library use.
+type ContractBackend struct {
+	eapi  *PublicEthereumAPI        // Wrapper around the Ethereum object to access metadata
+	bcapi *PublicBlockChainAPI      // Wrapper around the blockchain to access chain data
+	txapi *PublicTransactionPoolAPI // Wrapper around the transaction pool to access transaction data
+}
+
+// NewContractBackend creates a new native contract backend using an existing
+// Etheruem object.
+func NewContractBackend(eth *Ethereum) *ContractBackend {
+	return &ContractBackend{
+		eapi:  NewPublicEthereumAPI(eth),
+		bcapi: NewPublicBlockChainAPI(eth.chainConfig, eth.blockchain, eth.miner, eth.chainDb, eth.gpo, eth.eventMux, eth.accountManager),
+		txapi: NewPublicTransactionPoolAPI(eth),
+	}
+}
+
+// ContractCall implements bind.ContractCaller executing an Ethereum contract
+// call with the specified data as the input. The pending flag requests execution
+// against the pending block, not the stable head of the chain.
+func (b *ContractBackend) ContractCall(contract common.Address, data []byte, pending bool) ([]byte, error) {
+	// Convert the input args to the API spec
+	args := CallArgs{
+		To:   &contract,
+		Data: common.ToHex(data),
+	}
+	block := rpc.LatestBlockNumber
+	if pending {
+		block = rpc.PendingBlockNumber
+	}
+	// Execute the call and convert the output back to Go types
+	out, err := b.bcapi.Call(args, block)
+	if err == errNoCode {
+		err = bind.ErrNoCode
+	}
+	return common.FromHex(out), err
+}
+
+// PendingAccountNonce implements bind.ContractTransactor retrieving the current
+// pending nonce associated with an account.
+func (b *ContractBackend) PendingAccountNonce(account common.Address) (uint64, error) {
+	out, err := b.txapi.GetTransactionCount(account, rpc.PendingBlockNumber)
+	return out.Uint64(), err
+}
+
+// SuggestGasPrice implements bind.ContractTransactor retrieving the currently
+// suggested gas price to allow a timely execution of a transaction.
+func (b *ContractBackend) SuggestGasPrice() (*big.Int, error) {
+	return b.eapi.GasPrice(), nil
+}
+
+// EstimateGasLimit implements bind.ContractTransactor triing to estimate the gas
+// needed to execute a specific transaction based on the current pending state of
+// the backend blockchain. There is no guarantee that this is the true gas limit
+// requirement as other transactions may be added or removed by miners, but it
+// should provide a basis for setting a reasonable default.
+func (b *ContractBackend) EstimateGasLimit(sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) {
+	out, err := b.bcapi.EstimateGas(CallArgs{
+		From:  sender,
+		To:    contract,
+		Value: *rpc.NewHexNumber(value),
+		Data:  common.ToHex(data),
+	})
+	if err == errNoCode {
+		err = bind.ErrNoCode
+	}
+	return out.BigInt(), err
+}
+
+// SendTransaction implements bind.ContractTransactor injects the transaction
+// into the pending pool for execution.
+func (b *ContractBackend) SendTransaction(tx *types.Transaction) error {
+	raw, _ := rlp.EncodeToBytes(tx)
+	_, err := b.txapi.SendRawTransaction(common.ToHex(raw))
+	return err
+}