Renamed block_chain to chain_manager

1 files changed, 291 insertions, 0 deletions

diff --git a/ethchain/chain_manager.go b/ethchain/chain_manager.go
new file mode 100644
index 000000000..227b02c0a
--- /dev/null
+++ b/ethchain/chain_manager.go
@@ -0,0 +1,291 @@
+package ethchain
+
+import (
+	"bytes"
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethlog"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+var chainlogger = ethlog.NewLogger("CHAIN")
+
+type ChainManager struct {
+	Ethereum EthManager
+	// The famous, the fabulous Mister GENESIIIIIIS (block)
+	genesisBlock *Block
+	// Last known total difficulty
+	TD *big.Int
+
+	LastBlockNumber uint64
+
+	CurrentBlock  *Block
+	LastBlockHash []byte
+}
+
+func NewChainManager(ethereum EthManager) *ChainManager {
+	bc := &ChainManager{}
+	bc.genesisBlock = NewBlockFromBytes(ethutil.Encode(Genesis))
+	bc.Ethereum = ethereum
+
+	bc.setLastBlock()
+
+	return bc
+}
+
+func (bc *ChainManager) Genesis() *Block {
+	return bc.genesisBlock
+}
+
+func (bc *ChainManager) NewBlock(coinbase []byte) *Block {
+	var root interface{}
+	hash := ZeroHash256
+
+	if bc.CurrentBlock != nil {
+		root = bc.CurrentBlock.state.Trie.Root
+		hash = bc.LastBlockHash
+	}
+
+	block := CreateBlock(
+		root,
+		hash,
+		coinbase,
+		ethutil.BigPow(2, 32),
+		nil,
+		"")
+
+	block.MinGasPrice = big.NewInt(10000000000000)
+
+	parent := bc.CurrentBlock
+	if parent != nil {
+		block.Difficulty = CalcDifficulty(block, parent)
+		block.Number = new(big.Int).Add(bc.CurrentBlock.Number, ethutil.Big1)
+		block.GasLimit = block.CalcGasLimit(bc.CurrentBlock)
+
+	}
+
+	return block
+}
+
+func CalcDifficulty(block, parent *Block) *big.Int {
+	diff := new(big.Int)
+
+	adjust := new(big.Int).Rsh(parent.Difficulty, 10)
+	if block.Time >= parent.Time+5 {
+		diff.Sub(parent.Difficulty, adjust)
+	} else {
+		diff.Add(parent.Difficulty, adjust)
+	}
+
+	return diff
+}
+
+func (bc *ChainManager) Reset() {
+	AddTestNetFunds(bc.genesisBlock)
+
+	bc.genesisBlock.state.Trie.Sync()
+	// Prepare the genesis block
+	bc.Add(bc.genesisBlock)
+	fk := append([]byte("bloom"), bc.genesisBlock.Hash()...)
+	bc.Ethereum.Db().Put(fk, make([]byte, 255))
+	bc.CurrentBlock = bc.genesisBlock
+
+	bc.SetTotalDifficulty(ethutil.Big("0"))
+
+	// Set the last know difficulty (might be 0x0 as initial value, Genesis)
+	bc.TD = ethutil.BigD(ethutil.Config.Db.LastKnownTD())
+}
+
+func (bc *ChainManager) HasBlock(hash []byte) bool {
+	data, _ := ethutil.Config.Db.Get(hash)
+	return len(data) != 0
+}
+
+// TODO: At one point we might want to save a block by prevHash in the db to optimise this...
+func (bc *ChainManager) HasBlockWithPrevHash(hash []byte) bool {
+	block := bc.CurrentBlock
+
+	for ; block != nil; block = bc.GetBlock(block.PrevHash) {
+		if bytes.Compare(hash, block.PrevHash) == 0 {
+			return true
+		}
+	}
+	return false
+}
+
+func (bc *ChainManager) CalculateBlockTD(block *Block) *big.Int {
+	blockDiff := new(big.Int)
+
+	for _, uncle := range block.Uncles {
+		blockDiff = blockDiff.Add(blockDiff, uncle.Difficulty)
+	}
+	blockDiff = blockDiff.Add(blockDiff, block.Difficulty)
+
+	return blockDiff
+}
+
+func (bc *ChainManager) GenesisBlock() *Block {
+	return bc.genesisBlock
+}
+
+func (self *ChainManager) GetChainHashesFromHash(hash []byte, max uint64) (chain [][]byte) {
+	block := self.GetBlock(hash)
+	if block == nil {
+		return
+	}
+
+	// XXX Could be optimised by using a different database which only holds hashes (i.e., linked list)
+	for i := uint64(0); i < max; i++ {
+		chain = append(chain, block.Hash())
+
+		if block.Number.Cmp(ethutil.Big0) <= 0 {
+			break
+		}
+
+		block = self.GetBlock(block.PrevHash)
+	}
+
+	return
+}
+
+func AddTestNetFunds(block *Block) {
+	for _, addr := range []string{
+		"51ba59315b3a95761d0863b05ccc7a7f54703d99",
+		"e4157b34ea9615cfbde6b4fda419828124b70c78",
+		"b9c015918bdaba24b4ff057a92a3873d6eb201be",
+		"6c386a4b26f73c802f34673f7248bb118f97424a",
+		"cd2a3d9f938e13cd947ec05abc7fe734df8dd826",
+		"2ef47100e0787b915105fd5e3f4ff6752079d5cb",
+		"e6716f9544a56c530d868e4bfbacb172315bdead",
+		"1a26338f0d905e295fccb71fa9ea849ffa12aaf4",
+	} {
+		codedAddr := ethutil.Hex2Bytes(addr)
+		account := block.state.GetAccount(codedAddr)
+		account.Balance = ethutil.Big("1606938044258990275541962092341162602522202993782792835301376") //ethutil.BigPow(2, 200)
+		block.state.UpdateStateObject(account)
+	}
+}
+
+func (bc *ChainManager) setLastBlock() {
+	data, _ := ethutil.Config.Db.Get([]byte("LastBlock"))
+	if len(data) != 0 {
+		// Prep genesis
+		AddTestNetFunds(bc.genesisBlock)
+
+		block := NewBlockFromBytes(data)
+		bc.CurrentBlock = block
+		bc.LastBlockHash = block.Hash()
+		bc.LastBlockNumber = block.Number.Uint64()
+
+		// Set the last know difficulty (might be 0x0 as initial value, Genesis)
+		bc.TD = ethutil.BigD(ethutil.Config.Db.LastKnownTD())
+	} else {
+		bc.Reset()
+	}
+
+	chainlogger.Infof("Last block (#%d) %x\n", bc.LastBlockNumber, bc.CurrentBlock.Hash())
+}
+
+func (bc *ChainManager) SetTotalDifficulty(td *big.Int) {
+	ethutil.Config.Db.Put([]byte("LTD"), td.Bytes())
+	bc.TD = td
+}
+
+// Add a block to the chain and record addition information
+func (bc *ChainManager) Add(block *Block) {
+	bc.writeBlockInfo(block)
+	// Prepare the genesis block
+
+	bc.CurrentBlock = block
+	bc.LastBlockHash = block.Hash()
+
+	encodedBlock := block.RlpEncode()
+	ethutil.Config.Db.Put(block.Hash(), encodedBlock)
+	ethutil.Config.Db.Put([]byte("LastBlock"), encodedBlock)
+}
+
+func (self *ChainManager) CalcTotalDiff(block *Block) (*big.Int, error) {
+	parent := self.GetBlock(block.PrevHash)
+	if parent == nil {
+		return nil, fmt.Errorf("Unable to calculate total diff without known parent %x", block.PrevHash)
+	}
+
+	parentTd := parent.BlockInfo().TD
+
+	uncleDiff := new(big.Int)
+	for _, uncle := range block.Uncles {
+		uncleDiff = uncleDiff.Add(uncleDiff, uncle.Difficulty)
+	}
+
+	td := new(big.Int)
+	td = td.Add(parentTd, uncleDiff)
+	td = td.Add(td, block.Difficulty)
+
+	return td, nil
+}
+
+func (bc *ChainManager) GetBlock(hash []byte) *Block {
+	data, _ := ethutil.Config.Db.Get(hash)
+	if len(data) == 0 {
+		return nil
+	}
+
+	return NewBlockFromBytes(data)
+}
+
+func (self *ChainManager) GetBlockByNumber(num uint64) *Block {
+	block := self.CurrentBlock
+	for ; block != nil; block = self.GetBlock(block.PrevHash) {
+		if block.Number.Uint64() == num {
+			break
+		}
+	}
+
+	if block != nil && block.Number.Uint64() == 0 && num != 0 {
+		return nil
+	}
+
+	return block
+}
+
+func (self *ChainManager) GetBlockBack(num uint64) *Block {
+	block := self.CurrentBlock
+
+	for ; num != 0 && block != nil; num-- {
+		block = self.GetBlock(block.PrevHash)
+	}
+
+	return block
+}
+
+func (bc *ChainManager) BlockInfoByHash(hash []byte) BlockInfo {
+	bi := BlockInfo{}
+	data, _ := ethutil.Config.Db.Get(append(hash, []byte("Info")...))
+	bi.RlpDecode(data)
+
+	return bi
+}
+
+func (bc *ChainManager) BlockInfo(block *Block) BlockInfo {
+	bi := BlockInfo{}
+	data, _ := ethutil.Config.Db.Get(append(block.Hash(), []byte("Info")...))
+	bi.RlpDecode(data)
+
+	return bi
+}
+
+// Unexported method for writing extra non-essential block info to the db
+func (bc *ChainManager) writeBlockInfo(block *Block) {
+	bc.LastBlockNumber++
+	bi := BlockInfo{Number: bc.LastBlockNumber, Hash: block.Hash(), Parent: block.PrevHash, TD: bc.TD}
+
+	// For now we use the block hash with the words "info" appended as key
+	ethutil.Config.Db.Put(append(block.Hash(), []byte("Info")...), bi.RlpEncode())
+}
+
+func (bc *ChainManager) Stop() {
+	if bc.CurrentBlock != nil {
+		chainlogger.Infoln("Stopped")
+	}
+}