// queueTx will queue an unknown transaction
func (self *TxPool) queueTx(hash common.Hash, tx *types.Transaction) {
	from, _ := tx.From() // already validated
	if self.queue[from] == nil {
		self.queue[from] = make(map[common.Hash]*types.Transaction)
	}
	self.queue[from][hash] = tx
}

func (self *BlockProcessor) ApplyTransaction(coinbase *state.StateObject, statedb *state.StateDB, block *types.Block, tx *types.Transaction, usedGas *big.Int, transientProcess bool) (*types.Receipt, *big.Int, error) {
	// If we are mining this block and validating we want to set the logs back to 0
	//statedb.EmptyLogs()

	cb := statedb.GetStateObject(coinbase.Address())
	_, gas, err := ApplyMessage(NewEnv(statedb, self.bc, tx, block), tx, cb)
	if err != nil && (IsNonceErr(err) || state.IsGasLimitErr(err) || IsInvalidTxErr(err)) {
		// If the account is managed, remove the invalid nonce.
		//from, _ := tx.From()
		//self.bc.TxState().RemoveNonce(from, tx.Nonce())
		return nil, nil, err
	}

	// Update the state with pending changes
	statedb.Update()

	cumulative := new(big.Int).Set(usedGas.Add(usedGas, gas))
	receipt := types.NewReceipt(statedb.Root().Bytes(), cumulative)

	logs := statedb.GetLogs(tx.Hash())
	receipt.SetLogs(logs)
	receipt.Bloom = types.CreateBloom(types.Receipts{receipt})

	glog.V(logger.Debug).Infoln(receipt)

	// Notify all subscribers
	if !transientProcess {
		go self.eventMux.Post(TxPostEvent{tx})
		go self.eventMux.Post(logs)
	}

	return receipt, gas, err
}

func (app *EthereumApplication) AppendTx(txBytes []byte) (retCode types.RetCode, result []byte, log string) {
	// decode and run tx
	tx := new(ethtypes.Transaction)
	rlpStream := rlp.NewStream(bytes.NewBuffer(txBytes), 0)
	if err := tx.DecodeRLP(rlpStream); err != nil {
		return types.RetCodeEncodingError, result, log
	}

	gpi := big.NewInt(1000000000) // a billion ... TODO: configurable
	gp := core.GasPool(*gpi)      // XXX: this feels so wrong!?
	ret, gas, err := core.ApplyMessage(NewEnv(app.stateDB, tx), tx, &gp)
	if err != nil {
		if err == ethtypes.ErrInvalidSig || err == ethtypes.ErrInvalidPubKey {
			return types.RetCodeUnauthorized, result, err.Error()
		} else if core.IsNonceErr(err) {
			return types.RetCodeBadNonce, result, err.Error()
		} else if core.IsInvalidTxErr(err) {
			return types.RetCodeInsufficientFees, result, err.Error() // bad gas or value transfer
		} else {
			return types.RetCodeUnauthorized, result, err.Error() // bad pubkey recovery
		}
	}
	_, _ = ret, gas
	return types.RetCodeOK, result, log
}

func (self *BlockProcessor) ApplyTransaction(coinbase *state.StateObject, statedb *state.StateDB, header *types.Header, tx *types.Transaction, usedGas *big.Int, transientProcess bool) (*types.Receipt, *big.Int, error) {
	// If we are mining this block and validating we want to set the logs back to 0

	cb := statedb.GetStateObject(coinbase.Address())
	_, gas, err := ApplyMessage(NewEnv(statedb, self.bc, tx, header), tx, cb)
	if err != nil && (IsNonceErr(err) || state.IsGasLimitErr(err) || IsInvalidTxErr(err)) {
		return nil, nil, err
	}

	// Update the state with pending changes
	statedb.Update()

	usedGas.Add(usedGas, gas)
	receipt := types.NewReceipt(statedb.Root().Bytes(), usedGas)
	logs := statedb.GetLogs(tx.Hash())
	receipt.SetLogs(logs)
	receipt.Bloom = types.CreateBloom(types.Receipts{receipt})

	glog.V(logger.Debug).Infoln(receipt)

	// Notify all subscribers
	if !transientProcess {
		go self.eventMux.Post(TxPostEvent{tx})
		go self.eventMux.Post(logs)
	}

	return receipt, gas, err
}

func (self *XEth) sign(tx *types.Transaction, from common.Address, didUnlock bool) (*types.Transaction, error) {
	hash := tx.SigHash()
	sig, err := self.doSign(from, hash, didUnlock)
	if err != nil {
		return tx, err
	}
	return tx.WithSignature(sig)
}

func (self *XEth) sign(tx *types.Transaction, from common.Address, didUnlock bool) error {
	hash := tx.Hash()
	sig, err := self.doSign(from, hash, didUnlock)
	if err != nil {
		return err
	}
	tx.SetSignatureValues(sig)
	return nil
}

func (pool *TxPool) addTx(tx *types.Transaction) {
	if _, ok := pool.txs[tx.Hash()]; !ok {
		pool.txs[tx.Hash()] = tx
		// Notify the subscribers. This event is posted in a goroutine
		// because it's possible that somewhere during the post "Remove transaction"
		// gets called which will then wait for the global tx pool lock and deadlock.
		go pool.eventMux.Post(TxPreEvent{tx})
	}
}

func (self *ImportMaster) importTx(tx *types.Transaction, blockId *bson.ObjectId) {
	if glog.V(logger.Info) {
		glog.Infoln("Importing tx", tx.Hash().Hex())
	}
	err := self.txCollection.Insert(self.parseTx(tx, blockId))
	if err != nil {
		clilogger.Infoln(err)
	}
}

// AddTx adds a transaction to the generated block. If no coinbase has
// been set, the block's coinbase is set to the zero address.
//
// AddTx panics if the transaction cannot be executed. In addition to
// the protocol-imposed limitations (gas limit, etc.), there are some
// further limitations on the content of transactions that can be
// added. Notably, contract code relying on the BLOCKHASH instruction
// will panic during execution.
func (b *BlockGen) AddTx(tx *types.Transaction) {
	if b.gasPool == nil {
		b.SetCoinbase(common.Address{})
	}
	b.statedb.StartRecord(tx.Hash(), common.Hash{}, len(b.txs))
	receipt, _, _, err := ApplyTransaction(nil, b.gasPool, b.statedb, b.header, tx, b.header.GasUsed, nil)
	if err != nil {
		panic(err)
	}
	b.txs = append(b.txs, tx)
	b.receipts = append(b.receipts, receipt)
}

func (app *EthereumApplication) BroadcastTx(tx *ethtypes.Transaction) error {
	var result ctypes.TMResult
	buf := new(bytes.Buffer)
	if err := tx.EncodeRLP(buf); err != nil {
		return err
	}
	params := map[string]interface{}{
		"tx": hex.EncodeToString(buf.Bytes()),
	}
	_, err := app.client.Call("broadcast_tx", params, &result)
	return err
}

func (self *ImportMaster) parseTx(tx *types.Transaction, blockId *bson.ObjectId) *Transaction {
	hash := tx.Hash().Hex()
	from, err := tx.From()
	if err != nil {
		utils.Fatalf("Could not parse from address: %v", err)
	}
	var recipient string
	if tx.Recipient != nil {
		recipient = tx.Recipient.Hex()
	}
	txx := &Transaction{hash, recipient, from.Hex(), tx.Amount.String(), tx.Price.String(), tx.GasLimit.String(), tx.Payload, blockId}
	return txx
}

// addTx will add a transaction to the pending (processable queue) list of transactions
func (pool *TxPool) addTx(hash common.Hash, addr common.Address, tx *types.Transaction) {
	if _, ok := pool.pending[hash]; !ok {
		pool.pending[hash] = tx

		// Increment the nonce on the pending state. This can only happen if
		// the nonce is +1 to the previous one.
		pool.pendingState.SetNonce(addr, tx.Nonce()+1)
		// Notify the subscribers. This event is posted in a goroutine
		// because it's possible that somewhere during the post "Remove transaction"
		// gets called which will then wait for the global tx pool lock and deadlock.
		go pool.eventMux.Post(TxPreEvent{tx})
	}
}

func (self *BlockProcessor) ApplyTransaction(gp GasPool, statedb *state.StateDB, header *types.Header, tx *types.Transaction, usedGas *big.Int, transientProcess bool) (*types.Receipt, *big.Int, error) {
	_, gas, err := ApplyMessage(NewEnv(statedb, self.bc, tx, header), tx, gp)
	if err != nil {
		return nil, nil, err
	}

	// Update the state with pending changes
	statedb.SyncIntermediate()

	usedGas.Add(usedGas, gas)
	receipt := types.NewReceipt(statedb.Root().Bytes(), usedGas)
	receipt.TxHash = tx.Hash()
	receipt.GasUsed = new(big.Int).Set(gas)
	if MessageCreatesContract(tx) {
		from, _ := tx.From()
		receipt.ContractAddress = crypto.CreateAddress(from, tx.Nonce())
	}

	logs := statedb.GetLogs(tx.Hash())
	receipt.SetLogs(logs)
	receipt.Bloom = types.CreateBloom(types.Receipts{receipt})

	glog.V(logger.Debug).Infoln(receipt)

	// Notify all subscribers
	if !transientProcess {
		go self.eventMux.Post(TxPostEvent{tx})
		go self.eventMux.Post(logs)
	}

	return receipt, gas, err
}

// validateTx checks whether a transaction is valid according
// to the consensus rules.
func (pool *TxPool) validateTx(tx *types.Transaction) error {
	// Validate sender
	var (
		from common.Address
		err  error
	)

	// Drop transactions under our own minimal accepted gas price
	if pool.minGasPrice.Cmp(tx.GasPrice()) > 0 {
		return ErrCheap
	}

	// Validate the transaction sender and it's sig. Throw
	// if the from fields is invalid.
	if from, err = tx.From(); err != nil {
		return ErrInvalidSender
	}

	// Make sure the account exist. Non existent accounts
	// haven't got funds and well therefor never pass.
	if !pool.currentState().HasAccount(from) {
		return ErrNonExistentAccount
	}

	// Last but not least check for nonce errors
	if pool.currentState().GetNonce(from) > tx.Nonce() {
		return ErrNonce
	}

	// Check the transaction doesn't exceed the current
	// block limit gas.
	if pool.gasLimit().Cmp(tx.GasLimit) < 0 {
		return ErrGasLimit
	}

	// Transactions can't be negative. This may never happen
	// using RLP decoded transactions but may occur if you create
	// a transaction using the RPC for example.
	if tx.Amount.Cmp(common.Big0) < 0 {
		return ErrNegativeValue
	}

	// Transactor should have enough funds to cover the costs
	// cost == V + GP * GL
	total := new(big.Int).Mul(tx.Price, tx.GasLimit)
	total.Add(total, tx.Value())
	if pool.currentState().GetBalance(from).Cmp(total) < 0 {
		return ErrInsufficientFunds
	}

	// Should supply enough intrinsic gas
	if tx.GasLimit.Cmp(IntrinsicGas(tx)) < 0 {
		return ErrIntrinsicGas
	}

	return nil
}

// AddTx adds a transaction to the generated block. If no coinbase has
// been set, the block's coinbase is set to the zero address.
//
// AddTx panics if the transaction cannot be executed. In addition to
// the protocol-imposed limitations (gas limit, etc.), there are some
// further limitations on the content of transactions that can be
// added. Notably, contract code relying on the BLOCKHASH instruction
// will panic during execution.
func (b *BlockGen) AddTx(tx *types.Transaction) {
	if b.coinbase == nil {
		b.SetCoinbase(common.Address{})
	}
	_, gas, err := ApplyMessage(NewEnv(b.statedb, nil, tx, b.header), tx, b.coinbase)
	if err != nil {
		panic(err)
	}
	b.statedb.SyncIntermediate()
	b.header.GasUsed.Add(b.header.GasUsed, gas)
	receipt := types.NewReceipt(b.statedb.Root().Bytes(), b.header.GasUsed)
	logs := b.statedb.GetLogs(tx.Hash())
	receipt.SetLogs(logs)
	receipt.Bloom = types.CreateBloom(types.Receipts{receipt})
	b.txs = append(b.txs, tx)
	b.receipts = append(b.receipts, receipt)
}

func (self *XEth) sign(tx *types.Transaction, from common.Address, didUnlock bool) error {
	sig, err := self.backend.AccountManager().Sign(accounts.Account{Address: from.Bytes()}, tx.Hash().Bytes())
	if err == accounts.ErrLocked {
		if didUnlock {
			return fmt.Errorf("sender account still locked after successful unlock")
		}
		if !self.frontend.UnlockAccount(from.Bytes()) {
			return fmt.Errorf("could not unlock sender account")
		}
		// retry signing, the account should now be unlocked.
		return self.sign(tx, from, true)
	} else if err != nil {
		return err
	}
	tx.SetSignatureValues(sig)
	return nil
}

func (gui *Gui) insertTransaction(window string, tx *types.Transaction) {
	var inout string
	from, _ := tx.From()
	if gui.eth.AccountManager().HasAccount(common.Hex2Bytes(from.Hex())) {
		inout = "send"
	} else {
		inout = "recv"
	}

	ptx := xeth.NewTx(tx)
	ptx.Sender = from.Hex()
	if to := tx.To(); to != nil {
		ptx.Address = to.Hex()
	}

	if window == "post" {
		//gui.getObjectByName("transactionView").Call("addTx", ptx, inout)
	} else {
		gui.getObjectByName("pendingTxView").Call("addTx", ptx, inout)
	}
}

// validate and queue transactions.
func (self *TxPool) add(tx *types.Transaction) error {
	hash := tx.Hash()

	if self.pending[hash] != nil {
		return fmt.Errorf("Known transaction (%x)", hash[:4])
	}
	err := self.validateTx(tx)
	if err != nil {
		return err
	}
	self.queueTx(hash, tx)

	if glog.V(logger.Debug) {
		var toname string
		if to := tx.To(); to != nil {
			toname = common.Bytes2Hex(to[:4])
		} else {
			toname = "[NEW_CONTRACT]"
		}
		// we can ignore the error here because From is
		// verified in ValidateTransaction.
		f, _ := tx.From()
		from := common.Bytes2Hex(f[:4])
		glog.Infof("(t) %x => %s (%v) %x\n", from, toname, tx.Value, hash)
	}

	return nil
}

func putTx(db common.Database, tx *types.Transaction, block *types.Block, i uint64) {
	rlpEnc, err := rlp.EncodeToBytes(tx)
	if err != nil {
		glog.V(logger.Debug).Infoln("Failed encoding tx", err)
		return
	}
	db.Put(tx.Hash().Bytes(), rlpEnc)

	var txExtra struct {
		BlockHash  common.Hash
		BlockIndex uint64
		Index      uint64
	}
	txExtra.BlockHash = block.Hash()
	txExtra.BlockIndex = block.NumberU64()
	txExtra.Index = i
	rlpMeta, err := rlp.EncodeToBytes(txExtra)
	if err != nil {
		glog.V(logger.Debug).Infoln("Failed encoding tx meta data", err)
		return
	}
	db.Put(append(tx.Hash().Bytes(), 0x0001), rlpMeta)
}

// keep accounts synced up
func (self *Ethereum) syncAccounts(tx *types.Transaction) {
	from, err := tx.From()
	if err != nil {
		return
	}

	if self.accountManager.HasAccount(from.Bytes()) {
		if self.chainManager.TxState().GetNonce(from) < tx.Nonce() {
			self.chainManager.TxState().SetNonce(from, tx.Nonce())
		}
	}
}