1 files changed, 320 insertions, 0 deletions
diff --git a/ethchain/state_manager.go b/ethchain/state_manager.go
new file mode 100644
index 000000000..7085146df
--- /dev/null
+++ b/ethchain/state_manager.go
@@ -0,0 +1,320 @@
+package ethchain
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/ethereum/eth-go/ethutil"
+	"github.com/ethereum/eth-go/ethwire"
+	"math/big"
+	"sync"
+	"time"
+)
+
+type BlockProcessor interface {
+	ProcessBlock(block *Block)
+}
+
+type EthManager interface {
+	StateManager() *StateManager
+	BlockChain() *BlockChain
+	TxPool() *TxPool
+	Broadcast(msgType ethwire.MsgType, data []interface{})
+}
+
+// TODO rename to state manager
+type StateManager struct {
+	// Mutex for locking the block processor. Blocks can only be handled one at a time
+	mutex sync.Mutex
+
+	// Canonical block chain
+	bc *BlockChain
+	// States for addresses. You can watch any address
+	// at any given time
+	addrStateStore *AddrStateStore
+
+	// Stack for processing contracts
+	stack *Stack
+	// non-persistent key/value memory storage
+	mem map[string]*big.Int
+
+	Pow PoW
+
+	Ethereum EthManager
+
+	SecondaryBlockProcessor BlockProcessor
+
+	// The managed states
+	// Processor state. Anything processed will be applied to this
+	// state
+	procState *State
+	// Comparative state it used for comparing and validating end
+	// results
+	compState *State
+}
+
+func NewStateManager(ethereum EthManager) *StateManager {
+	sm := &StateManager{
+		stack:          NewStack(),
+		mem:            make(map[string]*big.Int),
+		Pow:            &EasyPow{},
+		Ethereum:       ethereum,
+		addrStateStore: NewAddrStateStore(),
+		bc:             ethereum.BlockChain(),
+	}
+
+	return sm
+}
+
+func (sm *StateManager) ProcState() *State {
+	return sm.procState
+}
+
+// Watches any given address and puts it in the address state store
+func (sm *StateManager) WatchAddr(addr []byte) *AccountState {
+	//FIXME account := sm.procState.GetAccount(addr)
+	account := sm.bc.CurrentBlock.state.GetAccount(addr)
+
+	return sm.addrStateStore.Add(addr, account)
+}
+
+func (sm *StateManager) GetAddrState(addr []byte) *AccountState {
+	account := sm.addrStateStore.Get(addr)
+	if account == nil {
+		a := sm.bc.CurrentBlock.state.GetAccount(addr)
+		account = &AccountState{Nonce: a.Nonce, Account: a}
+	}
+
+	return account
+}
+
+func (sm *StateManager) BlockChain() *BlockChain {
+	return sm.bc
+}
+
+func (sm *StateManager) MakeContract(tx *Transaction) {
+	contract := MakeContract(tx, sm.procState)
+	if contract != nil {
+		sm.procState.states[string(tx.Hash()[12:])] = contract.state
+	}
+}
+
+func (sm *StateManager) ApplyTransactions(block *Block, txs []*Transaction) {
+	// Process each transaction/contract
+	for _, tx := range txs {
+		// If there's no recipient, it's a contract
+		if tx.IsContract() {
+			//FIXME sm.MakeContract(tx)
+			block.MakeContract(tx)
+		} else {
+			//FIXME if contract := procState.GetContract(tx.Recipient); contract != nil {
+			if contract := block.state.GetContract(tx.Recipient); contract != nil {
+				sm.ProcessContract(contract, tx, block)
+			} else {
+				err := sm.Ethereum.TxPool().ProcessTransaction(tx, block)
+				if err != nil {
+					ethutil.Config.Log.Infoln("[smGR]", err)
+				}
+			}
+		}
+	}
+}
+
+// The prepare function, prepares the state manager for the next
+// "ProcessBlock" action.
+func (sm *StateManager) Prepare(processer *State, comparative *State) {
+	sm.compState = comparative
+	sm.procState = processer
+}
+
+// Default prepare function
+func (sm *StateManager) PrepareDefault(block *Block) {
+	sm.Prepare(sm.BlockChain().CurrentBlock.State(), block.State())
+}
+
+// Block processing and validating with a given (temporarily) state
+func (sm *StateManager) ProcessBlock(block *Block) error {
+	// Processing a blocks may never happen simultaneously
+	sm.mutex.Lock()
+	defer sm.mutex.Unlock()
+	// Defer the Undo on the Trie. If the block processing happened
+	// we don't want to undo but since undo only happens on dirty
+	// nodes this won't happen because Commit would have been called
+	// before that.
+	defer sm.bc.CurrentBlock.Undo()
+
+	hash := block.Hash()
+
+	if sm.bc.HasBlock(hash) {
+		return nil
+	}
+
+	// Check if we have the parent hash, if it isn't known we discard it
+	// Reasons might be catching up or simply an invalid block
+	if !sm.bc.HasBlock(block.PrevHash) && sm.bc.CurrentBlock != nil {
+		return ParentError(block.PrevHash)
+	}
+
+	// Process the transactions on to current block
+	sm.ApplyTransactions(sm.bc.CurrentBlock, block.Transactions())
+
+	// Block validation
+	if err := sm.ValidateBlock(block); err != nil {
+		return err
+	}
+
+	// I'm not sure, but I don't know if there should be thrown
+	// any errors at this time.
+	if err := sm.AccumelateRewards(sm.bc.CurrentBlock, block); err != nil {
+		return err
+	}
+
+	// if !sm.compState.Cmp(sm.procState)
+	if !block.state.Cmp(sm.bc.CurrentBlock.state) {
+		return fmt.Errorf("Invalid merkle root. Expected %x, got %x", block.State().trie.Root, sm.bc.CurrentBlock.State().trie.Root)
+		//FIXME return fmt.Errorf("Invalid merkle root. Expected %x, got %x", sm.compState.trie.Root, sm.procState.trie.Root)
+	}
+
+	// Calculate the new total difficulty and sync back to the db
+	if sm.CalculateTD(block) {
+		// Sync the current block's state to the database and cancelling out the deferred Undo
+		sm.bc.CurrentBlock.Sync()
+		//FIXME sm.procState.Sync()
+
+		// Broadcast the valid block back to the wire
+		//sm.Ethereum.Broadcast(ethwire.MsgBlockTy, []interface{}{block.Value().Val})
+
+		// Add the block to the chain
+		sm.bc.Add(block)
+
+		// If there's a block processor present, pass in the block for further
+		// processing
+		if sm.SecondaryBlockProcessor != nil {
+			sm.SecondaryBlockProcessor.ProcessBlock(block)
+		}
+
+		ethutil.Config.Log.Infof("[smGR] Added block #%d (%x)\n", block.BlockInfo().Number, block.Hash())
+	} else {
+		fmt.Println("total diff failed")
+	}
+
+	return nil
+}
+
+func (sm *StateManager) CalculateTD(block *Block) bool {
+	uncleDiff := new(big.Int)
+	for _, uncle := range block.Uncles {
+		uncleDiff = uncleDiff.Add(uncleDiff, uncle.Difficulty)
+	}
+
+	// TD(genesis_block) = 0 and TD(B) = TD(B.parent) + sum(u.difficulty for u in B.uncles) + B.difficulty
+	td := new(big.Int)
+	td = td.Add(sm.bc.TD, uncleDiff)
+	td = td.Add(td, block.Difficulty)
+
+	// The new TD will only be accepted if the new difficulty is
+	// is greater than the previous.
+	if td.Cmp(sm.bc.TD) > 0 {
+		// Set the new total difficulty back to the block chain
+		sm.bc.SetTotalDifficulty(td)
+
+		return true
+	}
+
+	return false
+}
+
+// Validates the current block. Returns an error if the block was invalid,
+// an uncle or anything that isn't on the current block chain.
+// Validation validates easy over difficult (dagger takes longer time = difficult)
+func (sm *StateManager) ValidateBlock(block *Block) error {
+	// TODO
+	// 2. Check if the difficulty is correct
+
+	// Check each uncle's previous hash. In order for it to be valid
+	// is if it has the same block hash as the current
+	previousBlock := sm.bc.GetBlock(block.PrevHash)
+	for _, uncle := range block.Uncles {
+		if bytes.Compare(uncle.PrevHash, previousBlock.PrevHash) != 0 {
+			return ValidationError("Mismatch uncle's previous hash. Expected %x, got %x", previousBlock.PrevHash, uncle.PrevHash)
+		}
+	}
+
+	diff := block.Time - sm.bc.CurrentBlock.Time
+	if diff < 0 {
+		return ValidationError("Block timestamp less then prev block %v", diff)
+	}
+
+	// New blocks must be within the 15 minute range of the last block.
+	if diff > int64(15*time.Minute) {
+		return ValidationError("Block is too far in the future of last block (> 15 minutes)")
+	}
+
+	// Verify the nonce of the block. Return an error if it's not valid
+	if !sm.Pow.Verify(block.HashNoNonce(), block.Difficulty, block.Nonce) {
+		return ValidationError("Block's nonce is invalid (= %v)", block.Nonce)
+	}
+
+	return nil
+}
+
+func CalculateBlockReward(block *Block, uncleLength int) *big.Int {
+	base := new(big.Int)
+	for i := 0; i < uncleLength; i++ {
+		base.Add(base, UncleInclusionReward)
+	}
+	return base.Add(base, BlockReward)
+}
+
+func CalculateUncleReward(block *Block) *big.Int {
+	return UncleReward
+}
+
+func (sm *StateManager) AccumelateRewards(processor *Block, block *Block) error {
+	// Get the coinbase rlp data
+	addr := processor.state.GetAccount(block.Coinbase)
+	//FIXME addr := proc.GetAccount(block.Coinbase)
+	// Reward amount of ether to the coinbase address
+	addr.AddFee(CalculateBlockReward(block, len(block.Uncles)))
+
+	processor.state.UpdateAccount(block.Coinbase, addr)
+	//FIXME proc.UpdateAccount(block.Coinbase, addr)
+
+	for _, uncle := range block.Uncles {
+		uncleAddr := processor.state.GetAccount(uncle.Coinbase)
+		uncleAddr.AddFee(CalculateUncleReward(uncle))
+
+		processor.state.UpdateAccount(uncle.Coinbase, uncleAddr)
+		//FIXME proc.UpdateAccount(uncle.Coinbase, uncleAddr)
+	}
+
+	return nil
+}
+
+func (sm *StateManager) Stop() {
+	sm.bc.Stop()
+}
+
+func (sm *StateManager) ProcessContract(contract *Contract, tx *Transaction, block *Block) {
+	// Recovering function in case the VM had any errors
+	/*
+		defer func() {
+			if r := recover(); r != nil {
+				fmt.Println("Recovered from VM execution with err =", r)
+			}
+		}()
+	*/
+
+	vm := &Vm{}
+	//vm.Process(contract, sm.procState, RuntimeVars{
+	vm.Process(contract, block.state, RuntimeVars{
+		address:     tx.Hash()[12:],
+		blockNumber: block.BlockInfo().Number,
+		sender:      tx.Sender(),
+		prevHash:    block.PrevHash,
+		coinbase:    block.Coinbase,
+		time:        block.Time,
+		diff:        block.Difficulty,
+		txValue:     tx.Value,
+		txData:      tx.Data,
+	})
+}