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 BlockChain 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 NewBlockChain(ethereum EthManager) *BlockChain {
bc := &BlockChain{}
bc.genesisBlock = NewBlockFromBytes(ethutil.Encode(Genesis))
bc.Ethereum = ethereum
bc.setLastBlock()
return bc
}
func (bc *BlockChain) Genesis() *Block {
return bc.genesisBlock
}
func (bc *BlockChain) 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 *BlockChain) 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 *BlockChain) 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 *BlockChain) 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 *BlockChain) 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 *BlockChain) GenesisBlock() *Block {
return bc.genesisBlock
}
func (self *BlockChain) 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 *BlockChain) 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 *BlockChain) 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 *BlockChain) 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 *BlockChain) 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 *BlockChain) GetBlock(hash []byte) *Block {
data, _ := ethutil.Config.Db.Get(hash)
if len(data) == 0 {
return nil
}
return NewBlockFromBytes(data)
}
func (self *BlockChain) 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 *BlockChain) GetBlockBack(num uint64) *Block {
block := self.CurrentBlock
for ; num != 0 && block != nil; num-- {
block = self.GetBlock(block.PrevHash)
}
return block
}
func (bc *BlockChain) BlockInfoByHash(hash []byte) BlockInfo {
bi := BlockInfo{}
data, _ := ethutil.Config.Db.Get(append(hash, []byte("Info")...))
bi.RlpDecode(data)
return bi
}
func (bc *BlockChain) 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 *BlockChain) 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 *BlockChain) Stop() {
if bc.CurrentBlock != nil {
chainlogger.Infoln("Stopped")
}
}
