package ethchain
import (
"bytes"
"github.com/ethereum/eth-go/ethutil"
"log"
"math"
"math/big"
)
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 = NewBlockFromData(ethutil.Encode(Genesis))
bc.setLastBlock()
return bc
}
func (bc *BlockChain) Genesis() *Block {
return bc.genesisBlock
}
func (bc *BlockChain) NewBlock(coinbase []byte, txs []*Transaction) *Block {
var root interface{}
var lastBlockTime int64
hash := ZeroHash256
if bc.CurrentBlock != nil {
root = bc.CurrentBlock.state.trie.Root
hash = bc.LastBlockHash
lastBlockTime = bc.CurrentBlock.Time
}
block := CreateBlock(
root,
hash,
coinbase,
ethutil.BigPow(2, 32),
nil,
"",
txs)
if bc.CurrentBlock != nil {
var mul *big.Int
if block.Time < lastBlockTime+42 {
mul = big.NewInt(1)
} else {
mul = big.NewInt(-1)
}
diff := new(big.Int)
diff.Add(diff, bc.CurrentBlock.Difficulty)
diff.Div(diff, big.NewInt(1024))
diff.Mul(diff, mul)
diff.Add(diff, bc.CurrentBlock.Difficulty)
block.Difficulty = diff
}
return block
}
func (bc *BlockChain) HasBlock(hash []byte) bool {
data, _ := ethutil.Config.Db.Get(hash)
return len(data) != 0
}
func (bc *BlockChain) GenesisBlock() *Block {
return bc.genesisBlock
}
// Get chain return blocks from hash up to max in RLP format
func (bc *BlockChain) GetChainFromHash(hash []byte, max uint64) []interface{} {
var chain []interface{}
// Get the current hash to start with
currentHash := bc.CurrentBlock.Hash()
// Get the last number on the block chain
lastNumber := bc.BlockInfo(bc.CurrentBlock).Number
// Get the parents number
parentNumber := bc.BlockInfoByHash(hash).Number
// Get the min amount. We might not have max amount of blocks
count := uint64(math.Min(float64(lastNumber-parentNumber), float64(max)))
startNumber := parentNumber + count
num := lastNumber
for ; num > startNumber; currentHash = bc.GetBlock(currentHash).PrevHash {
num--
}
for i := uint64(0); bytes.Compare(currentHash, hash) != 0 && num >= parentNumber && i < count; i++ {
// Get the block of the chain
block := bc.GetBlock(currentHash)
currentHash = block.PrevHash
chain = append(chain, block.Value().Val)
num--
}
return chain
}
func (bc *BlockChain) GetChain(hash []byte, amount int) []*Block {
genHash := bc.genesisBlock.Hash()
block := bc.GetBlock(hash)
var blocks []*Block
for i := 0; i < amount && block != nil; block = bc.GetBlock(block.PrevHash) {
blocks = append([]*Block{block}, blocks...)
if bytes.Compare(genHash, block.Hash()) == 0 {
break
}
i++
}
return blocks
}
func AddTestNetFunds(block *Block) {
for _, addr := range []string{
"8a40bfaa73256b60764c1bf40675a99083efb075", // Gavin
"e6716f9544a56c530d868e4bfbacb172315bdead", // Jeffrey
"1e12515ce3e0f817a4ddef9ca55788a1d66bd2df", // Vit
"1a26338f0d905e295fccb71fa9ea849ffa12aaf4", // Alex
} {
//log.Println("2^200 Wei to", addr)
codedAddr := ethutil.FromHex(addr)
addr := block.state.GetAccount(codedAddr)
addr.Amount = ethutil.BigPow(2, 200)
block.state.UpdateAccount(codedAddr, addr)
}
}
func (bc *BlockChain) setLastBlock() {
data, _ := ethutil.Config.Db.Get([]byte("LastBlock"))
if len(data) != 0 {
block := NewBlockFromBytes(data)
info := bc.BlockInfo(block)
bc.CurrentBlock = block
bc.LastBlockHash = block.Hash()
bc.LastBlockNumber = info.Number
log.Printf("[CHAIN] Last known block height #%d\n", bc.LastBlockNumber)
} else {
AddTestNetFunds(bc.genesisBlock)
bc.genesisBlock.state.trie.Sync()
// Prepare the genesis block
bc.Add(bc.genesisBlock)
//log.Printf("root %x\n", bm.bc.genesisBlock.State().Root)
//bm.bc.genesisBlock.PrintHash()
}
// Set the last know difficulty (might be 0x0 as initial value, Genesis)
bc.TD = ethutil.BigD(ethutil.Config.Db.LastKnownTD())
log.Printf("Last block: %x\n", bc.CurrentBlock.Hash())
}
func (bc *BlockChain) SetTotalDifficulty(td *big.Int) {
ethutil.Config.Db.Put([]byte("LastKnownTotalDifficulty"), 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 (bc *BlockChain) GetBlock(hash []byte) *Block {
data, _ := ethutil.Config.Db.Get(hash)
if len(data) == 0 {
return nil
}
return NewBlockFromData(data)
}
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}
// 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 {
log.Println("[CHAIN] Stopped")
}
}
