go-ethereum/core/blockchain.go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

// Package core implements the Ethereum consensus protocol.
package core

import (
	"errors"
	"fmt"
	"io"
	"math/big"
	"sync"
	"sync/atomic"
	"time"

	"github.com/XinFinOrg/XDPoSChain/XDCx/tradingstate"
	"github.com/XinFinOrg/XDPoSChain/XDCxlending/lendingstate"
	"github.com/XinFinOrg/XDPoSChain/accounts/abi/bind"
	"github.com/XinFinOrg/XDPoSChain/common"
	"github.com/XinFinOrg/XDPoSChain/common/lru"
	"github.com/XinFinOrg/XDPoSChain/common/mclock"
	"github.com/XinFinOrg/XDPoSChain/common/prque"
	"github.com/XinFinOrg/XDPoSChain/common/sort"
	"github.com/XinFinOrg/XDPoSChain/consensus"
	"github.com/XinFinOrg/XDPoSChain/consensus/XDPoS"
	"github.com/XinFinOrg/XDPoSChain/consensus/XDPoS/utils"
	contractValidator "github.com/XinFinOrg/XDPoSChain/contracts/validator/contract"
	"github.com/XinFinOrg/XDPoSChain/core/rawdb"
	"github.com/XinFinOrg/XDPoSChain/core/state"
	"github.com/XinFinOrg/XDPoSChain/core/tracing"
	"github.com/XinFinOrg/XDPoSChain/core/types"
	"github.com/XinFinOrg/XDPoSChain/core/vm"
	"github.com/XinFinOrg/XDPoSChain/crypto"
	"github.com/XinFinOrg/XDPoSChain/ethclient"
	"github.com/XinFinOrg/XDPoSChain/ethdb"
	"github.com/XinFinOrg/XDPoSChain/event"
	"github.com/XinFinOrg/XDPoSChain/internal/syncx"
	"github.com/XinFinOrg/XDPoSChain/log"
	"github.com/XinFinOrg/XDPoSChain/metrics"
	"github.com/XinFinOrg/XDPoSChain/params"
	"github.com/XinFinOrg/XDPoSChain/rlp"
	"github.com/XinFinOrg/XDPoSChain/trie"
)

var (
	headBlockGauge     = metrics.NewRegisteredGauge("chain/head/block", nil)
	headHeaderGauge    = metrics.NewRegisteredGauge("chain/head/header", nil)
	headFastBlockGauge = metrics.NewRegisteredGauge("chain/head/receipt", nil)

	chainInfoGauge = metrics.NewRegisteredGaugeInfo("chain/info", nil)

	accountReadTimer   = metrics.NewRegisteredResettingTimer("chain/account/reads", nil)
	accountHashTimer   = metrics.NewRegisteredResettingTimer("chain/account/hashes", nil)
	accountUpdateTimer = metrics.NewRegisteredResettingTimer("chain/account/updates", nil)
	accountCommitTimer = metrics.NewRegisteredResettingTimer("chain/account/commits", nil)

	storageReadTimer   = metrics.NewRegisteredResettingTimer("chain/storage/reads", nil)
	storageHashTimer   = metrics.NewRegisteredResettingTimer("chain/storage/hashes", nil)
	storageUpdateTimer = metrics.NewRegisteredResettingTimer("chain/storage/updates", nil)
	storageCommitTimer = metrics.NewRegisteredResettingTimer("chain/storage/commits", nil)

	triedbCommitTimer = metrics.NewRegisteredTimer("chain/triedb/commits", nil)

	blockInsertTimer     = metrics.NewRegisteredResettingTimer("chain/inserts", nil)
	blockValidationTimer = metrics.NewRegisteredResettingTimer("chain/validation", nil)
	blockExecutionTimer  = metrics.NewRegisteredResettingTimer("chain/execution", nil)
	blockWriteTimer      = metrics.NewRegisteredResettingTimer("chain/write", nil)

	blockReorgMeter     = metrics.NewRegisteredMeter("chain/reorg/executes", nil)
	blockReorgAddMeter  = metrics.NewRegisteredMeter("chain/reorg/add", nil)
	blockReorgDropMeter = metrics.NewRegisteredMeter("chain/reorg/drop", nil)

	blockPrefetchExecuteTimer   = metrics.NewRegisteredTimer("chain/prefetch/executes", nil)
	blockPrefetchInterruptMeter = metrics.NewRegisteredMeter("chain/prefetch/interrupts", nil)

	errInsertionInterrupted = errors.New("insertion is interrupted")
	errChainStopped         = errors.New("blockchain is stopped")
	errInvalidOldChain      = errors.New("invalid old chain")
	errInvalidNewChain      = errors.New("invalid new chain")

	CheckpointCh = make(chan int)
)

const (
	bodyCacheLimit      = 256
	blockCacheLimit     = 256
	receiptsCacheLimit  = 32
	maxFutureBlocks     = 256
	maxTimeFutureBlocks = 30
	triesInMemory       = 128

	// BlockChainVersion ensures that an incompatible database forces a resync from scratch.
	//
	// Changelog:
	//
	// - Version 4
	//   The following incompatible database changes were added:
	//   * the `BlockNumber`, `TxHash`, `TxIndex`, `BlockHash` and `Index` fields of log are deleted
	//   * the `Bloom` field of receipt is deleted
	//   * the `BlockIndex` and `TxIndex` fields of txlookup are deleted
	// - Version 5
	//  The following incompatible database changes were added:
	//    * the `TxHash`, `GasCost`, and `ContractAddress` fields are no longer stored for a receipt
	//    * the `TxHash`, `GasCost`, and `ContractAddress` fields are computed by looking up the
	//      receipts' corresponding block
	// - Version 6
	//  The following incompatible database changes were added:
	//    * Transaction lookup information stores the corresponding block number instead of block hash
	// - Version 7
	//  The following incompatible database changes were added:
	//    * New scheme for contract code in order to separate the codes and trie nodes
	BlockChainVersion uint64 = 7

	// Maximum length of chain to cache by block's number
	blocksHashCacheLimit = 900
)

// CacheConfig contains the configuration values for the trie database
// that's resident in a blockchain.
type CacheConfig struct {
	TrieCleanLimit    int           // Memory allowance (MB) to use for caching trie nodes in memory
	TrieCleanPrefetch bool          // Whether to enable heuristic state prefetching for followup blocks
	TrieDirtyLimit    int           // Memory limit (MB) at which to start flushing dirty trie nodes to disk
	TrieDirtyDisabled bool          // Whether to disable trie write caching and GC altogether (archive node)
	TrieTimeLimit     time.Duration // Time limit after which to flush the current in-memory trie to disk
	Preimages         bool          // Whether to store preimage of trie key to the disk
}

type ResultProcessBlock struct {
	logs         []*types.Log
	receipts     []*types.Receipt
	state        *state.StateDB
	tradingState *tradingstate.TradingStateDB
	lendingState *lendingstate.LendingStateDB
	proctime     time.Duration
	usedGas      uint64
}

// BlockChain represents the canonical chain given a database with a genesis
// block. The Blockchain manages chain imports, reverts, chain reorganisations.
//
// Importing blocks in to the block chain happens according to the set of rules
// defined by the two stage Validator. Processing of blocks is done using the
// Processor which processes the included transaction. The validation of the state
// is done in the second part of the Validator. Failing results in aborting of
// the import.
//
// The BlockChain also helps in returning blocks from **any** chain included
// in the database as well as blocks that represents the canonical chain. It's
// important to note that GetBlock can return any block and does not need to be
// included in the canonical one where as GetBlockByNumber always represents the
// canonical chain.
type BlockChain struct {
	chainConfig *params.ChainConfig // Chain & network configuration
	cacheConfig *CacheConfig        // Cache configuration for pruning

	db         ethdb.Database                   // Low level persistent database to store final content in
	XDCxDb     ethdb.XDCxDatabase               // XDCx database
	triegc     *prque.Prque[int64, common.Hash] // Priority queue mapping block numbers to tries to gc
	gcproc     time.Duration                    // Accumulates canonical block processing for trie dumping
	triedb     *trie.Database                   // The database handler for maintaining trie nodes.
	stateCache state.Database                   // State database to reuse between imports (contains state cache)

	hc            *HeaderChain
	rmLogsFeed    event.Feed
	chainFeed     event.Feed
	chainSideFeed event.Feed
	chainHeadFeed event.Feed
	logsFeed      event.Feed
	scope         event.SubscriptionScope
	genesisBlock  *types.Block

	// This mutex synchronizes chain write operations.
	// Readers don't need to take it, they can just read the database.
	chainmu *syncx.ClosableMutex

	currentBlock     atomic.Value // Current head of the block chain
	currentFastBlock atomic.Value // Current head of the fast-sync chain (may be above the block chain!)

	bodyCache        *lru.Cache[common.Hash, *types.Body]         // Cache for the most recent block bodies
	bodyRLPCache     *lru.Cache[common.Hash, rlp.RawValue]        // Cache for the most recent block bodies in RLP encoded format
	receiptsCache    *lru.Cache[common.Hash, types.Receipts]      // Cache for the most recent block receipts
	blockCache       *lru.Cache[common.Hash, *types.Block]        // Cache for the most recent entire blocks
	resultProcess    *lru.Cache[common.Hash, *ResultProcessBlock] // Cache for processed blocks
	calculatingBlock *lru.Cache[common.Hash, *CalculatedBlock]    // Cache for processing blocks
	downloadingBlock *lru.Cache[common.Hash, struct{}]            // Cache for downloading blocks (avoid duplication from fetcher)

	// future blocks are blocks added for later processing
	futureBlocks *lru.Cache[common.Hash, *types.Block]

	wg            sync.WaitGroup
	quit          chan struct{} // shutdown signal, closed in Stop.
	stopping      atomic.Bool   // false if chain is running, true when stopped
	procInterrupt atomic.Bool   // interrupt signaler for block processing

	engine     consensus.Engine
	validator  Validator  // Block and state validator interface
	prefetcher Prefetcher // Block state prefetcher interface
	processor  Processor  // Block transaction processor interface
	vmConfig   vm.Config
	logger     *tracing.Hooks

	IPCEndpoint string
	Client      bind.ContractBackend // Global ipc client instance.

	// Blocks hash array by block number
	// cache field for tracking finality purpose, can't use for tracking block vs block relationship
	blocksHashCache *lru.Cache[uint64, []common.Hash]

	resultTrade         *lru.Cache[common.Hash, interface{}] // trades result: key - takerOrderHash, value: trades corresponding to takerOrder
	rejectedOrders      *lru.Cache[common.Hash, interface{}] // rejected orders: key - takerOrderHash, value: rejected orders corresponding to takerOrder
	resultLendingTrade  *lru.Cache[common.Hash, interface{}]
	rejectedLendingItem *lru.Cache[common.Hash, interface{}]
	finalizedTrade      *lru.Cache[common.Hash, interface{}] // include both trades which force update to closed/liquidated by the protocol
}

// NewBlockChain returns a fully initialised block chain using information
// available in the database. It initialises the default Ethereum Validator and
// Processor.
func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *params.ChainConfig, engine consensus.Engine, vmConfig vm.Config) (*BlockChain, error) {
	if cacheConfig == nil {
		cacheConfig = &CacheConfig{
			TrieCleanLimit: 256,
			TrieDirtyLimit: 256,
			TrieTimeLimit:  5 * time.Minute,
		}
	}

	// Open trie database with provided config
	triedb := trie.NewDatabaseWithConfig(db, &trie.Config{
		Cache:     cacheConfig.TrieCleanLimit,
		Preimages: cacheConfig.Preimages,
	})
	bc := &BlockChain{
		chainConfig: chainConfig,
		cacheConfig: cacheConfig,
		db:          db,
		triedb:      triedb,
		triegc:      prque.New[int64, common.Hash](nil),
		stateCache: state.NewDatabaseWithConfig(db, &trie.Config{
			Cache:     cacheConfig.TrieCleanLimit,
			Preimages: cacheConfig.Preimages,
		}),
		quit:                make(chan struct{}),
		chainmu:             syncx.NewClosableMutex(),
		bodyCache:           lru.NewCache[common.Hash, *types.Body](bodyCacheLimit),
		bodyRLPCache:        lru.NewCache[common.Hash, rlp.RawValue](bodyCacheLimit),
		receiptsCache:       lru.NewCache[common.Hash, types.Receipts](receiptsCacheLimit),
		blockCache:          lru.NewCache[common.Hash, *types.Block](blockCacheLimit),
		futureBlocks:        lru.NewCache[common.Hash, *types.Block](maxFutureBlocks),
		resultProcess:       lru.NewCache[common.Hash, *ResultProcessBlock](blockCacheLimit),
		calculatingBlock:    lru.NewCache[common.Hash, *CalculatedBlock](blockCacheLimit),
		downloadingBlock:    lru.NewCache[common.Hash, struct{}](blockCacheLimit),
		engine:              engine,
		vmConfig:            vmConfig,
		logger:              vmConfig.Tracer,
		blocksHashCache:     lru.NewCache[uint64, []common.Hash](blocksHashCacheLimit),
		resultTrade:         lru.NewCache[common.Hash, interface{}](tradingstate.OrderCacheLimit),
		rejectedOrders:      lru.NewCache[common.Hash, interface{}](tradingstate.OrderCacheLimit),
		resultLendingTrade:  lru.NewCache[common.Hash, interface{}](tradingstate.OrderCacheLimit),
		rejectedLendingItem: lru.NewCache[common.Hash, interface{}](tradingstate.OrderCacheLimit),
		finalizedTrade:      lru.NewCache[common.Hash, interface{}](tradingstate.OrderCacheLimit),
	}
	bc.stateCache = state.NewDatabaseWithNodeDB(bc.db, bc.triedb)
	bc.validator = NewBlockValidator(chainConfig, bc, engine)
	bc.prefetcher = newStatePrefetcher(chainConfig, bc, engine)
	bc.processor = NewStateProcessor(chainConfig, bc, engine)

	var err error
	bc.hc, err = NewHeaderChain(db, chainConfig, engine, bc.insertStopped)
	if err != nil {
		return nil, err
	}
	bc.genesisBlock = bc.GetBlockByNumber(0)
	if bc.genesisBlock == nil {
		return nil, ErrNoGenesis
	}

	var nilBlock *types.Block
	bc.currentBlock.Store(nilBlock)
	bc.currentFastBlock.Store(nilBlock)

	// Update chain info data metrics
	chainInfoGauge.Update(metrics.GaugeInfoValue{"chain_id": bc.chainConfig.ChainID.String()})

	if err := bc.loadLastState(); err != nil {
		return nil, err
	}

	// Check the current state of the block hashes and make sure that we do not have any of the bad blocks in our chain
	for hash := range BadHashes {
		if header := bc.GetHeaderByHash(hash); header != nil {
			// get the canonical block corresponding to the offending header's number
			headerByNumber := bc.GetHeaderByNumber(header.Number.Uint64())
			// make sure the headerByNumber (if present) is in our current canonical chain
			if headerByNumber != nil && headerByNumber.Hash() == header.Hash() {
				log.Error("Found bad hash, rewinding chain", "number", header.Number, "hash", header.ParentHash)
				bc.SetHead(header.Number.Uint64() - 1)
				log.Error("Chain rewind was successful, resuming normal operation")
			}
		}
	}

	if bc.logger != nil && bc.logger.OnBlockchainInit != nil {
		bc.logger.OnBlockchainInit(chainConfig)
	}

	if bc.logger != nil && bc.logger.OnGenesisBlock != nil {
		if block := bc.CurrentBlock(); block.NumberU64() == 0 {
			alloc, err := getGenesisState(bc.db, block.Hash())
			if err != nil {
				return nil, fmt.Errorf("failed to get genesis state: %w", err)
			}

			if alloc == nil {
				return nil, fmt.Errorf("live blockchain tracer requires genesis alloc to be set")
			}

			bc.logger.OnGenesisBlock(bc.genesisBlock, alloc)
		}
	}

	// Start future block processor.
	bc.wg.Add(1)
	go bc.futureBlocksLoop()

	return bc, nil
}

// GetVMConfig returns the block chain VM config.
func (bc *BlockChain) GetVMConfig() *vm.Config {
	return &bc.vmConfig
}

// NewBlockChainEx extend old blockchain, add order state db
func NewBlockChainEx(db ethdb.Database, XDCxDb ethdb.XDCxDatabase, cacheConfig *CacheConfig, chainConfig *params.ChainConfig, engine consensus.Engine, vmConfig vm.Config) (*BlockChain, error) {
	blockchain, err := NewBlockChain(db, cacheConfig, chainConfig, engine, vmConfig)
	if err != nil {
		return nil, err
	}
	if blockchain != nil {
		blockchain.addXDCxDb(XDCxDb)
	}
	return blockchain, nil
}

func (bc *BlockChain) addXDCxDb(XDCxDb ethdb.XDCxDatabase) {
	bc.XDCxDb = XDCxDb
}

// loadLastState loads the last known chain state from the database. This method
// assumes that the chain manager mutex is held.
func (bc *BlockChain) loadLastState() error {
	// Restore the last known head block
	head := rawdb.ReadHeadBlockHash(bc.db)
	if head == (common.Hash{}) {
		// Corrupt or empty database, init from scratch
		log.Warn("Empty database, resetting chain")
		return bc.Reset()
	}
	// Make sure the entire head block is available
	currentBlock := bc.GetBlockByHash(head)
	if currentBlock == nil {
		// Corrupt or empty database, init from scratch
		log.Warn("Head block missing, resetting chain", "hash", head)
		return bc.Reset()
	}
	// Make sure the state associated with the block is available
	repair := false
	if !bc.HasState(currentBlock.Root()) {
		repair = true
	} else {
		engine, ok := bc.Engine().(*XDPoS.XDPoS)
		if ok {
			tradingService := engine.GetXDCXService()
			lendingService := engine.GetLendingService()
			if bc.Config().IsTIPXDCX(currentBlock.Number()) && bc.chainConfig.XDPoS != nil && currentBlock.NumberU64() > bc.chainConfig.XDPoS.Epoch && tradingService != nil && lendingService != nil {
				author, _ := bc.Engine().Author(currentBlock.Header())
				tradingRoot, err := tradingService.GetTradingStateRoot(currentBlock, author)
				if err != nil {
					repair = true
				} else {
					if tradingService.GetStateCache() != nil {
						_, err = tradingstate.New(tradingRoot, tradingService.GetStateCache())
						if err != nil {
							repair = true
						}
					}
				}

				if !repair {
					lendingRoot, err := lendingService.GetLendingStateRoot(currentBlock, author)
					if err != nil {
						repair = true
					} else {
						if lendingService.GetStateCache() != nil {
							_, err = lendingstate.New(lendingRoot, lendingService.GetStateCache())
							if err != nil {
								repair = true
							}
						}
					}
				}
			}
		}
	}
	if repair {
		// Dangling block without a state associated, init from scratch
		log.Warn("Head state missing, repairing chain", "number", currentBlock.Number(), "hash", currentBlock.Hash())
		if err := bc.repair(&currentBlock); err != nil {
			return err
		}
	}
	// Everything seems to be fine, set as the head block
	bc.currentBlock.Store(currentBlock)
	headBlockGauge.Update(int64(currentBlock.NumberU64()))

	// Restore the last known head header
	currentHeader := currentBlock.Header()
	if head := rawdb.ReadHeadHeaderHash(bc.db); head != (common.Hash{}) {
		if header := bc.GetHeaderByHash(head); header != nil {
			currentHeader = header
		}
	}
	bc.hc.SetCurrentHeader(currentHeader)

	// Restore the last known head fast block
	bc.currentFastBlock.Store(currentBlock)
	headFastBlockGauge.Update(int64(currentBlock.NumberU64()))

	if head := rawdb.ReadHeadFastBlockHash(bc.db); head != (common.Hash{}) {
		if block := bc.GetBlockByHash(head); block != nil {
			bc.currentFastBlock.Store(block)
			headFastBlockGauge.Update(int64(block.NumberU64()))
		}
	}

	// Issue a status log for the user
	currentFastBlock := bc.CurrentFastBlock()

	headerTd := bc.GetTd(currentHeader.Hash(), currentHeader.Number.Uint64())
	blockTd := bc.GetTd(currentBlock.Hash(), currentBlock.NumberU64())
	fastTd := bc.GetTd(currentFastBlock.Hash(), currentFastBlock.NumberU64())

	log.Info("Loaded most recent local header", "number", currentHeader.Number, "hash", currentHeader.Hash(), "td", headerTd, "age", common.PrettyAge(time.Unix(int64(currentHeader.Time), 0)))
	log.Info("Loaded most recent local full block", "number", currentBlock.Number(), "hash", currentBlock.Hash(), "td", blockTd, "age", common.PrettyAge(time.Unix(int64(currentBlock.Time()), 0)))
	log.Info("Loaded most recent local fast block", "number", currentFastBlock.Number(), "hash", currentFastBlock.Hash(), "td", fastTd, "age", common.PrettyAge(time.Unix(int64(currentFastBlock.Time()), 0)))

	return nil
}

// SetHead rewinds the local chain to a new head. Depending on whether the node
// was fast synced or full synced and in which state, the method will try to
// delete minimal data from disk whilst retaining chain consistency.
func (bc *BlockChain) SetHead(head uint64) error {
	if err := bc.setHeadBeyondRoot(head); err != nil {
		return err
	}
	// Send chain head event to update the transaction pool
	bc.chainHeadFeed.Send(ChainHeadEvent{Block: bc.CurrentBlock()})
	return nil
}

// setHeadBeyondRoot rewinds the local chain to a new head with the extra condition
// that the rewind must pass the specified state root. This method is meant to be
// used when rewinding with snapshots enabled to ensure that we go back further than
// persistent disk layer. Depending on whether the node was fast synced or full, and
// in which state, the method will try to delete minimal data from disk whilst
// retaining chain consistency.
func (bc *BlockChain) setHeadBeyondRoot(head uint64) error {
	if !bc.chainmu.TryLock() {
		return errChainStopped
	}
	defer bc.chainmu.Unlock()

	updateFn := func(db ethdb.KeyValueWriter, header *types.Header) {
		// Rewind the block chain, ensuring we don't end up with a stateless head block
		if currentBlock := bc.CurrentBlock(); currentBlock != nil && header.Number.Uint64() < currentBlock.NumberU64() {
			newHeadBlock := bc.GetBlock(header.Hash(), header.Number.Uint64())
			if newHeadBlock == nil {
				newHeadBlock = bc.genesisBlock
			} else {
				if !bc.HasState(newHeadBlock.Root()) {
					// Rewound state missing, rolled back to before pivot, reset to genesis
					newHeadBlock = bc.genesisBlock
				}
			}
			rawdb.WriteHeadBlockHash(db, newHeadBlock.Hash())

			// Degrade the chain markers if they are explicitly reverted.
			// In theory we should update all in-memory markers in the
			// last step, however the direction of SetHead is from high
			// to low, so it's safe the update in-memory markers directly.
			bc.currentBlock.Store(newHeadBlock)
			headBlockGauge.Update(int64(newHeadBlock.NumberU64()))
		}

		// Rewind the fast block in a simpleton way to the target head
		if currentFastBlock := bc.CurrentFastBlock(); currentFastBlock != nil && header.Number.Uint64() < currentFastBlock.NumberU64() {
			newHeadFastBlock := bc.GetBlock(header.Hash(), header.Number.Uint64())
			// If either blocks reached nil, reset to the genesis state
			if newHeadFastBlock == nil {
				newHeadFastBlock = bc.genesisBlock
			}
			rawdb.WriteHeadFastBlockHash(db, newHeadFastBlock.Hash())

			// Degrade the chain markers if they are explicitly reverted.
			// In theory we should update all in-memory markers in the
			// last step, however the direction of SetHead is from high
			// to low, so it's safe the update in-memory markers directly.
			bc.currentFastBlock.Store(newHeadFastBlock)
			headFastBlockGauge.Update(int64(newHeadFastBlock.NumberU64()))
		}
	}

	// Rewind the header chain, deleting all block bodies until then
	delFn := func(db ethdb.KeyValueWriter, hash common.Hash, num uint64) {
		// Ignore the error here since light client won't hit this path
		frozen, _ := bc.db.Ancients()
		if num+1 <= frozen {
			// Truncate all relative data(header, total difficulty, body, receipt
			// and canonical hash) from ancient store.
			if err := bc.db.TruncateAncients(num + 1); err != nil {
				log.Crit("Failed to truncate ancient data", "number", num, "err", err)
			}

			// Remove the hash <-> number mapping from the active store.
			rawdb.DeleteHeaderNumber(db, hash)
		} else {
			// Remove relative body and receipts from the active store.
			// The header, total difficulty and canonical hash will be
			// removed in the hc.SetHead function.
			rawdb.DeleteBody(db, hash, num)
			rawdb.DeleteReceipts(db, hash, num)
		}
		// Todo(rjl493456442) txlookup, bloombits, etc
	}
	bc.hc.SetHead(head, updateFn, delFn)

	// Clear out any stale content from the caches
	bc.bodyCache.Purge()
	bc.bodyRLPCache.Purge()
	bc.receiptsCache.Purge()
	bc.blockCache.Purge()
	bc.futureBlocks.Purge()
	bc.blocksHashCache.Purge()

	return bc.loadLastState()
}

// FastSyncCommitHead sets the current head block to the one defined by the hash
// irrelevant what the chain contents were prior.
func (bc *BlockChain) FastSyncCommitHead(hash common.Hash) error {
	// Make sure that both the block as well at its state trie exists
	block := bc.GetBlockByHash(hash)
	if block == nil {
		return fmt.Errorf("non existent block [%x..]", hash[:4])
	}
	root := block.Root()
	if !bc.HasState(root) {
		return fmt.Errorf("non existent state [%x..]", root[:4])
	}
	// If all checks out, manually set the head block.
	if !bc.chainmu.TryLock() {
		return errChainStopped
	}
	bc.currentBlock.Store(block)
	headBlockGauge.Update(int64(block.NumberU64()))
	bc.chainmu.Unlock()

	log.Info("Committed new head block", "number", block.Number(), "hash", hash)
	return nil
}

// GasLimit returns the gas limit of the current HEAD block.
func (bc *BlockChain) GasLimit() uint64 {
	return bc.CurrentBlock().GasLimit()
}

// CurrentBlock retrieves the current head block of the canonical chain. The
// block is retrieved from the blockchain's internal cache.
func (bc *BlockChain) CurrentBlock() *types.Block {
	return bc.currentBlock.Load().(*types.Block)
}

// CurrentFastBlock retrieves the current fast-sync head block of the canonical
// chain. The block is retrieved from the blockchain's internal cache.
func (bc *BlockChain) CurrentFastBlock() *types.Block {
	return bc.currentFastBlock.Load().(*types.Block)
}

// Validator returns the current validator.
func (bc *BlockChain) Validator() Validator {
	return bc.validator
}

// Processor returns the current processor.
func (bc *BlockChain) Processor() Processor {
	return bc.processor
}

// State returns a new mutable state based on the current HEAD block.
func (bc *BlockChain) State() (*state.StateDB, error) {
	return bc.StateAt(bc.CurrentBlock().Root())
}

// StateAt returns a new mutable state based on a particular point in time.
func (bc *BlockChain) StateAt(root common.Hash) (*state.StateDB, error) {
	return state.New(root, bc.stateCache)
}

// StateCache returns the caching database underpinning the blockchain instance.
func (bc *BlockChain) StateCache() state.Database {
	return bc.stateCache
}

// OrderStateAt returns a new mutable state based on a particular point in time.
func (bc *BlockChain) OrderStateAt(block *types.Block) (*tradingstate.TradingStateDB, error) {
	engine, ok := bc.Engine().(*XDPoS.XDPoS)
	if ok {
		XDCXService := engine.GetXDCXService()
		if bc.Config().IsTIPXDCX(block.Number()) && bc.chainConfig.XDPoS != nil && block.NumberU64() > bc.chainConfig.XDPoS.Epoch && XDCXService != nil {
			author, _ := bc.Engine().Author(block.Header())
			log.Debug("OrderStateAt", "blocknumber", block.Header().Number)
			XDCxState, err := XDCXService.GetTradingState(block, author)
			if err == nil {
				return XDCxState, nil
			} else {
				return nil, err
			}
		} else {
			XDCxState, err := XDCXService.GetEmptyTradingState()
			if err == nil {
				return XDCxState, nil
			} else {
				return nil, err
			}
		}
	}
	return nil, errors.New("fail to get trading state")
}

// LendingStateAt returns a new mutable state based on a particular point in time.
func (bc *BlockChain) LendingStateAt(block *types.Block) (*lendingstate.LendingStateDB, error) {
	engine, ok := bc.Engine().(*XDPoS.XDPoS)
	if ok {
		lendingService := engine.GetLendingService()
		if bc.Config().IsTIPXDCX(block.Number()) && bc.chainConfig.XDPoS != nil && block.NumberU64() > bc.chainConfig.XDPoS.Epoch && lendingService != nil {
			author, _ := bc.Engine().Author(block.Header())
			log.Debug("LendingStateAt", "blocknumber", block.Header().Number)
			lendingState, err := lendingService.GetLendingState(block, author)
			if err == nil {
				return lendingState, nil
			}
			return nil, err
		}
	}
	return nil, errors.New("fail to et lending state")
}

// Reset purges the entire blockchain, restoring it to its genesis state.
func (bc *BlockChain) Reset() error {
	return bc.ResetWithGenesisBlock(bc.genesisBlock)
}

// ResetWithGenesisBlock purges the entire blockchain, restoring it to the
// specified genesis state.
func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) error {
	// Dump the entire block chain and purge the caches
	if err := bc.SetHead(0); err != nil {
		return err
	}
	if !bc.chainmu.TryLock() {
		return errChainStopped
	}
	defer bc.chainmu.Unlock()

	// Prepare the genesis block and reinitialise the chain
	batch := bc.db.NewBatch()
	rawdb.WriteTd(batch, genesis.Hash(), genesis.NumberU64(), genesis.Difficulty())
	rawdb.WriteBlock(batch, genesis)
	if err := batch.Write(); err != nil {
		log.Crit("Failed to write genesis block", "err", err)
	}
	bc.writeHeadBlock(genesis, false)

	// Last update all in-memory chain markers
	bc.genesisBlock = genesis
	bc.currentBlock.Store(bc.genesisBlock)
	headBlockGauge.Update(int64(bc.genesisBlock.NumberU64()))
	bc.hc.SetGenesis(bc.genesisBlock.Header())
	bc.hc.SetCurrentHeader(bc.genesisBlock.Header())
	bc.currentFastBlock.Store(bc.genesisBlock)
	headFastBlockGauge.Update(int64(bc.genesisBlock.NumberU64()))
	return nil
}

// repair tries to repair the current blockchain by rolling back the current block
// until one with associated state is found. This is needed to fix incomplete db
// writes caused either by crashes/power outages, or simply non-committed tries.
//
// This method only rolls back the current block. The current header and current
// fast block are left intact.
func (bc *BlockChain) repair(head **types.Block) error {
	for {
		// Abort if we've rewound to a head block that does have associated state
		if (common.RollbackNumber == 0) || ((*head).Number().Uint64() < common.RollbackNumber) {
			if bc.HasState((*head).Root()) {
				log.Info("Rewound blockchain to past state", "number", (*head).Number(), "hash", (*head).Hash())
				engine, ok := bc.Engine().(*XDPoS.XDPoS)
				if ok {
					tradingService := engine.GetXDCXService()
					lendingService := engine.GetLendingService()
					if bc.Config().IsTIPXDCXReceiver((*head).Number()) && bc.chainConfig.XDPoS != nil && (*head).NumberU64() > bc.chainConfig.XDPoS.Epoch && tradingService != nil && lendingService != nil {
						author, _ := bc.Engine().Author((*head).Header())
						tradingRoot, err := tradingService.GetTradingStateRoot(*head, author)
						if err == nil {
							_, err = tradingstate.New(tradingRoot, tradingService.GetStateCache())
						}
						if err == nil {
							lendingRoot, err := lendingService.GetLendingStateRoot(*head, author)
							if err == nil {
								_, err = lendingstate.New(lendingRoot, lendingService.GetStateCache())
								if err == nil {
									return nil
								}
							}
						}
					} else {
						return nil
					}
				} else {
					return nil
				}
			}
		} else {
			log.Info("Rewound blockchain to past state", "number", (*head).Number(), "hash", (*head).Hash())
		}
		// Otherwise rewind one block and recheck state availability there
		block := bc.GetBlock((*head).ParentHash(), (*head).NumberU64()-1)
		if block == nil {
			panic(fmt.Sprintf("repair fail to get block at number: %v, hash: %v", (*head).NumberU64()-1, (*head).ParentHash()))
		}
		(*head) = block
	}
}

// Export writes the active chain to the given writer.
func (bc *BlockChain) Export(w io.Writer) error {
	return bc.ExportN(w, uint64(0), bc.CurrentBlock().NumberU64())
}

// ExportN writes a subset of the active chain to the given writer.
func (bc *BlockChain) ExportN(w io.Writer, first uint64, last uint64) error {
	if !bc.chainmu.TryLock() {
		return errChainStopped
	}
	defer bc.chainmu.Unlock()

	if first > last {
		return fmt.Errorf("export failed: first (%d) is greater than last (%d)", first, last)
	}
	log.Info("Exporting batch of blocks", "count", last-first+1)

	start, reported := time.Now(), time.Now()
	for nr := first; nr <= last; nr++ {
		block := bc.GetBlockByNumber(nr)
		if block == nil {
			return fmt.Errorf("export failed on #%d: not found", nr)
		}
		if err := block.EncodeRLP(w); err != nil {
			return err
		}
		if time.Since(reported) >= statsReportLimit {
			log.Info("Exporting blocks", "exported", block.NumberU64()-first, "elapsed", common.PrettyDuration(time.Since(start)))
			reported = time.Now()
		}
	}

	return nil
}

// writeHeadBlock injects a new head block into the current block chain. This method
// assumes that the block is indeed a true head. It will also reset the head
// header and the head fast sync block to this very same block if they are older
// or if they are on a different side chain.
//
// Note, this function assumes that the `mu` mutex is held!
func (bc *BlockChain) writeHeadBlock(block *types.Block, writeBlock bool) {
	blockHash := block.Hash()
	blockNumberU64 := block.NumberU64()

	// Add the block to the canonical chain number scheme and mark as the head
	batch := bc.db.NewBatch()
	rawdb.WriteHeadHeaderHash(batch, blockHash)
	rawdb.WriteHeadFastBlockHash(batch, blockHash)
	rawdb.WriteCanonicalHash(batch, blockHash, blockNumberU64)
	rawdb.WriteTxLookupEntriesByBlock(batch, block)
	rawdb.WriteHeadBlockHash(batch, blockHash)
	if writeBlock {
		rawdb.WriteBlock(batch, block)
	}

	// Flush the whole batch into the disk, exit the node if failed
	if err := batch.Write(); err != nil {
		log.Crit("Failed to update chain indexes and markers", "err", err)
	}

	// Update all in-memory chain markers in the last step
	bc.hc.SetCurrentHeader(block.Header())

	bc.currentFastBlock.Store(block)
	headFastBlockGauge.Update(int64(blockNumberU64))

	bc.currentBlock.Store(block)
	headBlockGauge.Update(int64(block.NumberU64()))

	// save cache BlockSigners
	if bc.chainConfig.XDPoS != nil && !bc.chainConfig.IsTIPSigning(block.Number()) {
		engine, ok := bc.Engine().(*XDPoS.XDPoS)
		if ok {
			engine.CacheNoneTIPSigningTxs(block.Header(), block.Transactions(), bc.GetReceiptsByHash(blockHash))
		}
	}
}

// Genesis retrieves the chain's genesis block.
func (bc *BlockChain) Genesis() *types.Block {
	return bc.genesisBlock
}

// GetBody retrieves a block body (transactions and uncles) from the database by
// hash, caching it if found.
func (bc *BlockChain) GetBody(hash common.Hash) *types.Body {
	// Short circuit if the body's already in the cache, retrieve otherwise
	if cached, ok := bc.bodyCache.Get(hash); ok {
		return cached
	}
	number := bc.hc.GetBlockNumber(hash)
	if number == nil {
		return nil
	}
	body := rawdb.ReadBody(bc.db, hash, *number)
	if body == nil {
		return nil
	}
	// Cache the found body for next time and return
	bc.bodyCache.Add(hash, body)
	return body
}

// GetBodyRLP retrieves a block body in RLP encoding from the database by hash,
// caching it if found.
func (bc *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue {
	// Short circuit if the body's already in the cache, retrieve otherwise
	if cached, ok := bc.bodyRLPCache.Get(hash); ok {
		return cached
	}
	number := bc.hc.GetBlockNumber(hash)
	if number == nil {
		return nil
	}
	body := rawdb.ReadBodyRLP(bc.db, hash, *number)
	if len(body) == 0 {
		return nil
	}
	// Cache the found body for next time and return
	bc.bodyRLPCache.Add(hash, body)
	return body
}

// HasBlock checks if a block is fully present in the database or not.
func (bc *BlockChain) HasBlock(hash common.Hash, number uint64) bool {
	if bc.blockCache.Contains(hash) {
		return true
	}
	if !bc.HasHeader(hash, number) {
		return false
	}
	return rawdb.HasBody(bc.db, hash, number)
}

// HasFastBlock checks if a fast block is fully present in the database or not.
func (bc *BlockChain) HasFastBlock(hash common.Hash, number uint64) bool {
	if !bc.HasBlock(hash, number) {
		return false
	}
	if bc.receiptsCache.Contains(hash) {
		return true
	}
	return rawdb.HasReceipts(bc.db, hash, number)
}

// HasState checks if state trie is fully present in the database or not.
func (bc *BlockChain) HasState(hash common.Hash) bool {
	_, err := bc.stateCache.OpenTrie(hash)
	return err == nil
}

// HasFullState checks if state trie is fully present in the database or not.
func (bc *BlockChain) HasFullState(block *types.Block) bool {
	_, err := bc.stateCache.OpenTrie(block.Root())
	if err != nil {
		return false
	}
	engine, _ := bc.Engine().(*XDPoS.XDPoS)
	if bc.Config().IsTIPXDCX(block.Number()) && bc.chainConfig.XDPoS != nil && engine != nil && block.NumberU64() > bc.chainConfig.XDPoS.Epoch {
		tradingService := engine.GetXDCXService()
		lendingService := engine.GetLendingService()
		author, _ := bc.Engine().Author(block.Header())
		if tradingService != nil && !tradingService.HasTradingState(block, author) {
			return false
		}
		if lendingService != nil && !lendingService.HasLendingState(block, author) {
			return false
		}
	}
	return true
}

// HasBlockAndFullState checks if a block and associated state trie is fully present
// in the database or not, caching it if present.
func (bc *BlockChain) HasBlockAndFullState(hash common.Hash, number uint64) bool {
	// Check first that the block itself is known
	block := bc.GetBlock(hash, number)
	if block == nil {
		return false
	}
	return bc.HasFullState(block)
}

// GetBlock retrieves a block from the database by hash and number,
// caching it if found.
func (bc *BlockChain) GetBlock(hash common.Hash, number uint64) *types.Block {
	// Short circuit if the block's already in the cache, retrieve otherwise
	if block, ok := bc.blockCache.Get(hash); ok {
		return block
	}
	block := rawdb.ReadBlock(bc.db, hash, number)
	if block == nil {
		return nil
	}
	// Cache the found block for next time and return
	bc.blockCache.Add(block.Hash(), block)
	return block
}

// GetBlockByHash retrieves a block from the database by hash, caching it if found.
func (bc *BlockChain) GetBlockByHash(hash common.Hash) *types.Block {
	number := bc.hc.GetBlockNumber(hash)
	if number == nil {
		return nil
	}
	return bc.GetBlock(hash, *number)
}

// GetBlockByNumber retrieves a block from the database by number, caching it
// (associated with its hash) if found.
func (bc *BlockChain) GetBlockByNumber(number uint64) *types.Block {
	hash := rawdb.ReadCanonicalHash(bc.db, number)
	if hash == (common.Hash{}) {
		return nil
	}
	return bc.GetBlock(hash, number)
}

// GetReceiptsByHash retrieves the receipts for all transactions in a given block.
func (bc *BlockChain) GetReceiptsByHash(hash common.Hash) types.Receipts {
	if receipts, ok := bc.receiptsCache.Get(hash); ok {
		return receipts
	}
	number := rawdb.ReadHeaderNumber(bc.db, hash)
	if number == nil {
		return nil
	}
	receipts := rawdb.ReadReceipts(bc.db, hash, *number, bc.chainConfig)
	if receipts == nil {
		return nil
	}
	bc.receiptsCache.Add(hash, receipts)
	return receipts
}

// GetBlocksFromHash returns the block corresponding to hash and up to n-1 ancestors.
// [deprecated by eth/62]
func (bc *BlockChain) GetBlocksFromHash(hash common.Hash, n int) (blocks []*types.Block) {
	number := bc.hc.GetBlockNumber(hash)
	if number == nil {
		return nil
	}
	for i := 0; i < n; i++ {
		block := bc.GetBlock(hash, *number)
		if block == nil {
			break
		}
		blocks = append(blocks, block)
		hash = block.ParentHash()
		*number--
	}
	return
}

// GetBlocksHashCache get all block's hashes with same level
// just work with latest blocksHashCacheLimit
func (bc *BlockChain) GetBlocksHashCache(number uint64) []common.Hash {
	cached, ok := bc.blocksHashCache.Get(number)

	if ok {
		return cached
	}
	return nil
}

// AreTwoBlockSamePath check if two blocks are same path
// Assume block 1 is ahead block 2 so we need to check parentHash
func (bc *BlockChain) AreTwoBlockSamePath(bh1 common.Hash, bh2 common.Hash) bool {
	bl1 := bc.GetBlockByHash(bh1)
	bl2 := bc.GetBlockByHash(bh2)
	if bl1 == nil || bl2 == nil {
		return false
	}

	toBlockLevel := bl2.Number().Uint64()
	for bl1.Number().Uint64() > toBlockLevel {
		bl1 = bc.GetBlockByHash(bl1.ParentHash())
		if bl1 == nil {
			return false
		}
	}

	return (bl1.Hash() == bl2.Hash())
}

// GetUnclesInChain retrieves all the uncles from a given block backwards until
// a specific distance is reached.
func (bc *BlockChain) GetUnclesInChain(block *types.Block, length int) []*types.Header {
	uncles := []*types.Header{}
	for i := 0; block != nil && i < length; i++ {
		uncles = append(uncles, block.Uncles()...)
		block = bc.GetBlock(block.ParentHash(), block.NumberU64()-1)
	}
	return uncles
}

// TrieNode retrieves a blob of data associated with a trie node
// either from ephemeral in-memory cache, or from persistent storage.
func (bc *BlockChain) TrieNode(hash common.Hash) ([]byte, error) {
	return bc.stateCache.TrieDB().Node(hash)
}

// ContractCode retrieves a blob of data associated with a contract hash
// either from ephemeral in-memory cache, or from persistent storage.
func (bc *BlockChain) ContractCode(hash common.Hash) ([]byte, error) {
	return bc.stateCache.ContractCode(common.Hash{}, hash)
}

// ContractCodeWithPrefix retrieves a blob of data associated with a contract
// hash either from ephemeral in-memory cache, or from persistent storage.
//
// If the code doesn't exist in the in-memory cache, check the storage with
// new code scheme.
func (bc *BlockChain) ContractCodeWithPrefix(hash common.Hash) ([]byte, error) {
	type codeReader interface {
		ContractCodeWithPrefix(addrHash, codeHash common.Hash) ([]byte, error)
	}
	return bc.stateCache.(codeReader).ContractCodeWithPrefix(common.Hash{}, hash)
}

func (bc *BlockChain) saveData() {
	// Ensure the state of a recent block is also stored to disk before exiting.
	// We're writing three different states to catch different restart scenarios:
	//  - HEAD:     So we don't need to reprocess any blocks in the general case
	//  - HEAD-1:   So we don't do large reorgs if our HEAD becomes an uncle
	//  - HEAD-127: So we have a hard limit on the number of blocks reexecuted
	if !bc.cacheConfig.TrieDirtyDisabled {
		var tradingTriedb *trie.Database
		var lendingTriedb *trie.Database
		var tradingService utils.TradingService
		var lendingService utils.LendingService
		triedb := bc.triedb
		engine, _ := bc.Engine().(*XDPoS.XDPoS)
		if bc.Config().IsTIPXDCX(bc.CurrentBlock().Number()) && bc.chainConfig.XDPoS != nil && bc.CurrentBlock().NumberU64() > bc.chainConfig.XDPoS.Epoch && engine != nil {
			tradingService = engine.GetXDCXService()
			if tradingService != nil && tradingService.GetStateCache() != nil {
				tradingTriedb = tradingService.GetStateCache().TrieDB()
			}
			lendingService = engine.GetLendingService()
			if lendingService != nil && lendingService.GetStateCache() != nil {
				lendingTriedb = lendingService.GetStateCache().TrieDB()
			}
		}
		for _, offset := range []uint64{0, 1, triesInMemory - 1} {
			if number := bc.CurrentBlock().NumberU64(); number > offset {
				recent := bc.GetBlockByNumber(number - offset)

				log.Info("Writing cached state to disk", "block", recent.Number(), "hash", recent.Hash(), "root", recent.Root())
				if err := triedb.Commit(recent.Root(), true); err != nil {
					log.Error("Failed to commit recent state trie", "err", err)
				}
				if bc.Config().IsTIPXDCXReceiver(recent.Number()) && bc.chainConfig.XDPoS != nil && recent.NumberU64() > bc.chainConfig.XDPoS.Epoch && engine != nil {
					author, _ := bc.Engine().Author(recent.Header())
					if tradingService != nil {
						tradingRoot, _ := tradingService.GetTradingStateRoot(recent, author)
						if !tradingRoot.IsZero() && tradingTriedb != nil {
							if err := tradingTriedb.Commit(tradingRoot, true); err != nil {
								log.Error("Failed to commit trading state recent state trie", "err", err)
							}
						}
					}
					if lendingService != nil {
						lendingRoot, _ := lendingService.GetLendingStateRoot(recent, author)
						if !lendingRoot.IsZero() && lendingTriedb != nil {
							if err := lendingTriedb.Commit(lendingRoot, true); err != nil {
								log.Error("Failed to commit lending state recent state trie", "err", err)
							}
						}
					}
				}
			}
		}
		for !bc.triegc.Empty() {
			triedb.Dereference(bc.triegc.PopItem())
		}
		if tradingTriedb != nil && lendingTriedb != nil {
			if tradingService.GetTriegc() != nil {
				for !tradingService.GetTriegc().Empty() {
					tradingTriedb.Dereference(tradingService.GetTriegc().PopItem())
				}
			}
			if lendingService.GetTriegc() != nil {
				for !lendingService.GetTriegc().Empty() {
					lendingTriedb.Dereference(lendingService.GetTriegc().PopItem())
				}
			}
		}
		if size, _ := triedb.Size(); size != 0 {
			log.Error("Dangling trie nodes after full cleanup")
		}
	}
}

// Stop stops the blockchain service. If any imports are currently in progress
// it will abort them using the procInterrupt.
func (bc *BlockChain) Stop() {
	if !bc.stopping.CompareAndSwap(false, true) {
		return
	}

	// Unsubscribe all subscriptions registered from blockchain.
	bc.scope.Close()

	// Signal shutdown to all goroutines.
	close(bc.quit)
	bc.InterruptInsert(true)

	// Now wait for all chain modifications to end and persistent goroutines to exit.
	//
	// Note: Close waits for the mutex to become available, i.e. any running chain
	// modification will have exited when Close returns. Since we also called StopInsert,
	// the mutex should become available quickly. It cannot be taken again after Close has
	// returned.
	bc.chainmu.Close()
	bc.wg.Wait()
	bc.saveData()
	// Allow tracers to clean-up and release resources.
	if bc.logger != nil && bc.logger.OnClose != nil {
		bc.logger.OnClose()
	}
	// Flush the collected preimages to disk
	if err := bc.stateCache.TrieDB().CommitPreimages(); err != nil {
		log.Error("Failed to commit trie preimages", "err", err)
	}
	log.Info("Blockchain manager stopped")
}

// InterruptInsert interrupts all insertion methods, causing them to return
// errInsertionInterrupted as soon as possible, or resume the chain insertion
// if required.
func (bc *BlockChain) InterruptInsert(on bool) {
	if on {
		bc.procInterrupt.Store(true)
	} else {
		bc.procInterrupt.Store(false)
	}
}

// insertStopped returns true after StopInsert has been called.
func (bc *BlockChain) insertStopped() bool {
	return bc.procInterrupt.Load()
}

func (bc *BlockChain) procFutureBlocks() {
	capacity := bc.futureBlocks.Len()
	if capacity == 0 {
		return
	}
	blocks := make([]*types.Block, 0, capacity)
	for _, hash := range bc.futureBlocks.Keys() {
		if block, exist := bc.futureBlocks.Peek(hash); exist {
			blocks = append(blocks, block)
		}
	}
	if len(blocks) > 0 {
		types.BlockBy(types.Number).Sort(blocks)

		// Insert one by one as chain insertion needs contiguous ancestry between blocks
		for i := range blocks {
			_, err := bc.InsertChain(blocks[i : i+1])
			// let consensus engine handle the last block (e.g. for voting)
			if i == len(blocks)-1 && err == nil {
				engine, ok := bc.Engine().(*XDPoS.XDPoS)
				if ok {
					header := blocks[i].Header()
					err = engine.HandleProposedBlock(bc, header)
					if err != nil {
						log.Info("[procFutureBlocks] handle proposed block has error", "err", err, "block hash", header.Hash(), "number", header.Number)
					}
				}
			}
		}
	}
}

// WriteStatus status of write
type WriteStatus byte

const (
	NonStatTy WriteStatus = iota
	CanonStatTy
	SideStatTy
)

// Rollback is designed to remove a chain of links from the database that aren't
// certain enough to be valid.
func (bc *BlockChain) Rollback(chain []common.Hash) {
	if !bc.chainmu.TryLock() {
		return
	}
	defer bc.chainmu.Unlock()

	batch := bc.db.NewBatch()
	for i := len(chain) - 1; i >= 0; i-- {
		hash := chain[i]

		// Degrade the chain markers if they are explicitly reverted.
		// In theory, we should update all in-memory markers in the
		// last step, however the direction of rollback is from high
		// to low, so it's safe the update in-memory markers directly.
		currentHeader := bc.hc.CurrentHeader()
		if currentHeader.Hash() == hash {
			newHeadHeader := bc.GetHeader(currentHeader.ParentHash, currentHeader.Number.Uint64()-1)
			rawdb.WriteHeadHeaderHash(batch, currentHeader.ParentHash)
			bc.hc.SetCurrentHeader(newHeadHeader)
		}
		if currentFastBlock := bc.CurrentFastBlock(); currentFastBlock.Hash() == hash {
			newFastBlock := bc.GetBlock(currentFastBlock.ParentHash(), currentFastBlock.NumberU64()-1)
			rawdb.WriteHeadFastBlockHash(batch, currentFastBlock.ParentHash())
			bc.currentFastBlock.Store(newFastBlock)
			headFastBlockGauge.Update(int64(newFastBlock.NumberU64()))
		}
		if currentBlock := bc.CurrentBlock(); currentBlock.Hash() == hash {
			newBlock := bc.GetBlock(currentBlock.ParentHash(), currentBlock.NumberU64()-1)
			rawdb.WriteHeadBlockHash(batch, currentBlock.ParentHash())
			bc.currentBlock.Store(newBlock)
			headBlockGauge.Update(int64(newBlock.NumberU64()))
		}
	}
	if err := batch.Write(); err != nil {
		log.Crit("Failed to rollback chain markers", "err", err)
	}
	// TODO: Truncate ancient data which exceeds the current header.
}

// InsertReceiptChain attempts to complete an already existing header chain with
// transaction and receipt data.
func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain []types.Receipts) (int, error) {
	// We don't require the chainMu here since we want to maximize the
	// concurrency of header insertion and receipt insertion.
	bc.wg.Add(1)
	defer bc.wg.Done()

	// Do a sanity check that the provided chain is actually ordered and linked
	for i := 1; i < len(blockChain); i++ {
		if blockChain[i].NumberU64() != blockChain[i-1].NumberU64()+1 || blockChain[i].ParentHash() != blockChain[i-1].Hash() {
			log.Error("Non contiguous receipt insert", "number", blockChain[i].Number(), "hash", blockChain[i].Hash(), "parent", blockChain[i].ParentHash(),
				"prevnumber", blockChain[i-1].Number(), "prevhash", blockChain[i-1].Hash())
			return 0, fmt.Errorf("non contiguous insert: item %d is #%d [%x..], item %d is #%d [%x..] (parent [%x..])", i-1, blockChain[i-1].NumberU64(),
				blockChain[i-1].Hash().Bytes()[:4], i, blockChain[i].NumberU64(), blockChain[i].Hash().Bytes()[:4], blockChain[i].ParentHash().Bytes()[:4])
		}
	}

	var (
		stats = struct{ processed, ignored int32 }{}
		start = time.Now()
		bytes = 0
		batch = bc.db.NewBatch()
	)
	for i, block := range blockChain {
		receipts := receiptChain[i]
		// Short circuit insertion if shutting down or processing failed
		if bc.insertStopped() {
			return 0, nil
		}
		blockHash, blockNumber := block.Hash(), block.NumberU64()
		// Short circuit if the owner header is unknown
		if !bc.HasHeader(blockHash, blockNumber) {
			return i, fmt.Errorf("containing header #%d [%x..] unknown", blockNumber, blockHash.Bytes()[:4])
		}
		// Skip if the entire data is already known
		if bc.HasBlock(blockHash, blockNumber) {
			stats.ignored++
			continue
		}
		// Compute all the non-consensus fields of the receipts
		if err := receipts.DeriveFields(bc.chainConfig, blockHash, blockNumber, block.BaseFee(), block.Transactions()); err != nil {
			return i, fmt.Errorf("failed to derive receipts data: %v", err)
		}
		// Write all the data out into the database
		rawdb.WriteBody(batch, blockHash, blockNumber, block.Body())
		rawdb.WriteReceipts(batch, blockHash, blockNumber, receipts)
		rawdb.WriteTxLookupEntriesByBlock(batch, block)

		// Write everything belongs to the blocks into the database. So that
		// we can ensure all components of body is completed(body, receipts,
		// tx indexes)
		if batch.ValueSize() >= ethdb.IdealBatchSize {
			if err := batch.Write(); err != nil {
				return 0, err
			}
			bytes += batch.ValueSize()
			batch.Reset()
		}
		stats.processed++
	}
	// Write everything belongs to the blocks into the database. So that
	// we can ensure all components of body is completed(body, receipts,
	// tx indexes)
	if batch.ValueSize() > 0 {
		bytes += batch.ValueSize()
		if err := batch.Write(); err != nil {
			return 0, err
		}
	}

	// Update the head fast sync block if better
	if !bc.chainmu.TryLock() {
		return 0, errChainStopped
	}
	head := blockChain[len(blockChain)-1]
	if td := bc.GetTd(head.Hash(), head.NumberU64()); td != nil { // Rewind may have occurred, skip in that case
		currentFastBlock := bc.CurrentFastBlock()
		if bc.GetTd(currentFastBlock.Hash(), currentFastBlock.NumberU64()).Cmp(td) < 0 {
			rawdb.WriteHeadFastBlockHash(bc.db, head.Hash())
			bc.currentFastBlock.Store(head)
			headFastBlockGauge.Update(int64(head.NumberU64()))
		}
	}
	bc.chainmu.Unlock()

	context := []interface{}{
		"count", stats.processed, "elapsed", common.PrettyDuration(time.Since(start)),
		"number", head.Number(), "hash", head.Hash(), "age", common.PrettyAge(time.Unix(int64(head.Time()), 0)),
		"size", common.StorageSize(bytes),
	}
	if stats.ignored > 0 {
		context = append(context, []interface{}{"ignored", stats.ignored}...)
	}
	log.Info("Imported new block receipts", context...)

	return 0, nil
}

var lastWrite uint64

// writeBlockWithoutState writes only the block and its metadata to the database,
// but does not write any state. This is used to construct competing side forks
// up to the point where they exceed the canonical total difficulty.
func (bc *BlockChain) writeBlockWithoutState(block *types.Block, td *big.Int) (err error) {
	if bc.insertStopped() {
		return errInsertionInterrupted
	}

	batch := bc.db.NewBatch()
	rawdb.WriteTd(batch, block.Hash(), block.NumberU64(), td)
	rawdb.WriteBlock(batch, block)
	if err := batch.Write(); err != nil {
		log.Crit("Failed to write block into disk", "err", err)
	}
	return nil
}

// WriteBlockWithState writes the block and all associated state to the database.
func (bc *BlockChain) WriteBlockWithState(block *types.Block, receipts []*types.Receipt, state *state.StateDB, tradingState *tradingstate.TradingStateDB, lendingState *lendingstate.LendingStateDB) (status WriteStatus, err error) {
	if !bc.chainmu.TryLock() {
		return NonStatTy, errInsertionInterrupted
	}
	defer bc.chainmu.Unlock()
	return bc.writeBlockWithState(block, receipts, state, tradingState, lendingState)
}

// writeBlockWithState writes the block and all associated state to the database,
// but is expects the chain mutex to be held.
func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.Receipt, state *state.StateDB, tradingState *tradingstate.TradingStateDB, lendingState *lendingstate.LendingStateDB) (status WriteStatus, err error) {
	if bc.insertStopped() {
		return NonStatTy, errInsertionInterrupted
	}

	// Calculate the total difficulty of the block
	ptd := bc.GetTd(block.ParentHash(), block.NumberU64()-1)
	if ptd == nil {
		return NonStatTy, consensus.ErrUnknownAncestor
	}
	// Make sure no inconsistent state is leaked during insertion
	currentBlock := bc.CurrentBlock()
	localTd := bc.GetTd(currentBlock.Hash(), currentBlock.NumberU64())
	externTd := new(big.Int).Add(block.Difficulty(), ptd)

	// Irrelevant of the canonical status, write the block itself to the database.
	//
	// Note all the components of block(td, hash->number map, header, body, receipts)
	// should be written atomically. BlockBatch is used for containing all components.
	blockBatch := bc.db.NewBatch()
	rawdb.WriteTd(blockBatch, block.Hash(), block.NumberU64(), externTd)
	rawdb.WriteBlock(blockBatch, block)
	rawdb.WriteReceipts(blockBatch, block.Hash(), block.NumberU64(), receipts)
	rawdb.WritePreimages(blockBatch, state.Preimages())
	if err := blockBatch.Write(); err != nil {
		log.Crit("Failed to write block into disk", "err", err)
	}
	// Commit all cached state changes into underlying memory database.
	root, err := state.Commit(bc.chainConfig.IsEIP158(block.Number()))
	if err != nil {
		return NonStatTy, err
	}

	tradingRoot := common.Hash{}
	if tradingState != nil {
		tradingRoot, err = tradingState.Commit()
		if err != nil {
			return NonStatTy, err
		}
	}
	lendingRoot := common.Hash{}
	if lendingState != nil {
		lendingRoot, err = lendingState.Commit()
		if err != nil {
			return NonStatTy, err
		}
	}

	engine, _ := bc.Engine().(*XDPoS.XDPoS)
	var tradingTrieDb *trie.Database
	var tradingService utils.TradingService
	var lendingTrieDb *trie.Database
	var lendingService utils.LendingService
	if bc.Config().IsTIPXDCXReceiver(block.Number()) && bc.chainConfig.XDPoS != nil && block.NumberU64() > bc.chainConfig.XDPoS.Epoch && engine != nil {
		tradingService = engine.GetXDCXService()
		if tradingService != nil {
			tradingTrieDb = tradingService.GetStateCache().TrieDB()
		}
		lendingService = engine.GetLendingService()
		if lendingService != nil {
			lendingTrieDb = lendingService.GetStateCache().TrieDB()
		}
	}

	// If we're running an archive node, always flush
	if bc.cacheConfig.TrieDirtyDisabled {
		if err := bc.triedb.Commit(root, false); err != nil {
			return NonStatTy, err
		}
		if tradingTrieDb != nil {
			if err := tradingTrieDb.Commit(tradingRoot, false); err != nil {
				return NonStatTy, err
			}
		}
		if lendingTrieDb != nil {
			if err := lendingTrieDb.Commit(lendingRoot, false); err != nil {
				return NonStatTy, err
			}
		}
	} else {
		// Full but not archive node, do proper garbage collection
		bc.triedb.Reference(root, common.Hash{}) // metadata reference to keep trie alive
		bc.triegc.Push(root, -int64(block.NumberU64()))
		if tradingTrieDb != nil {
			tradingTrieDb.Reference(tradingRoot, common.Hash{})
		}
		if tradingService != nil {
			tradingService.GetTriegc().Push(tradingRoot, -int64(block.NumberU64()))
		}
		if lendingTrieDb != nil {
			lendingTrieDb.Reference(lendingRoot, common.Hash{})
		}
		if lendingService != nil {
			lendingService.GetTriegc().Push(lendingRoot, -int64(block.NumberU64()))
		}
		if current := block.NumberU64(); current > triesInMemory {
			// Find the next state trie we need to commit
			chosen := current - triesInMemory
			// Only write to disk if we exceeded our memory allowance *and* also have at
			// least a given number of tries gapped.
			//
			//if tradingTrieDb != nil {
			//	size = size + tradingTrieDb.Size()
			//}
			//if lendingTrieDb != nil {
			//	size = size + lendingTrieDb.Size()
			//}
			var (
				nodes, imgs = bc.triedb.Size()
				limit       = common.StorageSize(bc.cacheConfig.TrieDirtyLimit) * 1024 * 1024
			)
			if nodes > limit || imgs > 4*1024*1024 {
				bc.triedb.Cap(limit - ethdb.IdealBatchSize)
			}
			if bc.gcproc > bc.cacheConfig.TrieTimeLimit || chosen > lastWrite+triesInMemory {
				// If the header is missing (canonical chain behind), we're reorging a low
				// diff sidechain. Suspend committing until this operation is completed.
				header := bc.GetHeaderByNumber(chosen)
				if header == nil {
					log.Warn("Reorg in progress, trie commit postponed", "number", chosen)
				} else {
					// If we're exceeding limits but haven't reached a large enough memory gap,
					// warn the user that the system is becoming unstable.
					if chosen < lastWrite+triesInMemory && bc.gcproc >= 2*bc.cacheConfig.TrieTimeLimit {
						log.Info("State in memory for too long, committing", "time", bc.gcproc, "allowance", bc.cacheConfig.TrieTimeLimit, "optimum", float64(chosen-lastWrite)/triesInMemory)
					}
					// Flush an entire trie and restart the counters
					bc.triedb.Commit(header.Root, true)
					lastWrite = chosen
					bc.gcproc = 0
					if tradingTrieDb != nil && lendingTrieDb != nil {
						b := bc.GetBlock(header.Hash(), current-triesInMemory)
						author, _ := bc.Engine().Author(b.Header())
						oldTradingRoot, _ := tradingService.GetTradingStateRoot(b, author)
						oldLendingRoot, _ := lendingService.GetLendingStateRoot(b, author)
						tradingTrieDb.Commit(oldTradingRoot, true)
						lendingTrieDb.Commit(oldLendingRoot, true)
					}
				}
			}
			// Garbage collect anything below our required write retention
			for !bc.triegc.Empty() {
				root, number := bc.triegc.Pop()
				if uint64(-number) > chosen {
					bc.triegc.Push(root, number)
					break
				}
				bc.triedb.Dereference(root)
			}
			if tradingService != nil {
				for !tradingService.GetTriegc().Empty() {
					tradingRoot, number := tradingService.GetTriegc().Pop()
					if uint64(-number) > chosen {
						tradingService.GetTriegc().Push(tradingRoot, number)
						break
					}
					tradingTrieDb.Dereference(tradingRoot)
				}
			}
			if lendingService != nil {
				for !lendingService.GetTriegc().Empty() {
					lendingRoot, number := lendingService.GetTriegc().Pop()
					if uint64(-number) > chosen {
						lendingService.GetTriegc().Push(lendingRoot, number)
						break
					}
					lendingTrieDb.Dereference(lendingRoot)
				}
			}
		}
	}

	// If the total difficulty is higher than our known, add it to the canonical chain
	// Second clause in the if statement reduces the vulnerability to selfish mining.
	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
	reorg := externTd.Cmp(localTd) > 0
	currentBlock = bc.CurrentBlock()
	if !reorg && externTd.Cmp(localTd) == 0 {
		// Split same-difficulty blocks by number
		reorg = block.NumberU64() > currentBlock.NumberU64()
	}
	if reorg {
		// Reorganise the chain if the parent is not the head block
		if block.ParentHash() != currentBlock.Hash() {
			if err := bc.reorg(currentBlock.Header(), block.Header()); err != nil {
				return NonStatTy, err
			}
		}
		status = CanonStatTy
	} else {
		status = SideStatTy
	}

	// Set new head.
	if status == CanonStatTy {
		// WriteBlock has already been called, no need to write again
		bc.writeHeadBlock(block, false)
		// prepare set of masternodes for the next epoch
		if bc.chainConfig.XDPoS != nil && ((block.NumberU64() % bc.chainConfig.XDPoS.Epoch) == (bc.chainConfig.XDPoS.Epoch - bc.chainConfig.XDPoS.Gap)) {
			if err := bc.UpdateM1(); err != nil {
				log.Crit("Fail to update masternodes during writeBlockWithState", "number", block.Number, "hash", block.Hash().Hex(), "err", err)
			}
		}
	}
	// save cache BlockSigners
	if bc.chainConfig.XDPoS != nil && bc.chainConfig.IsTIPSigning(block.Number()) {
		engine, ok := bc.Engine().(*XDPoS.XDPoS)
		if ok {
			engine.CacheSigningTxs(block.Header().Hash(), block.Transactions())
		}
	}
	bc.futureBlocks.Remove(block.Hash())
	return status, nil
}

// addFutureBlock checks if the block is within the max allowed window to get
// accepted for future processing, and returns an error if the block is too far
// ahead and was not added.
func (bc *BlockChain) addFutureBlock(block *types.Block) error {
	max := uint64(time.Now().Unix()) + maxTimeFutureBlocks
	if block.Time() > max {
		return fmt.Errorf("future block timestamp %v > allowed %v", block.Time(), max)
	}
	bc.futureBlocks.Add(block.Hash(), block)
	return nil
}

// InsertChain attempts to insert the given batch of blocks in to the canonical
// chain or, otherwise, create a fork. If an error is returned it will return
// the index number of the failing block as well an error describing what went
// wrong.
//
// After insertion is done, all accumulated events will be fired.
func (bc *BlockChain) InsertChain(chain types.Blocks) (int, error) {
	// Sanity check that we have something meaningful to import
	if len(chain) == 0 {
		return 0, nil
	}

	// Do a sanity check that the provided chain is actually ordered and linked
	for i := 1; i < len(chain); i++ {
		block, prev := chain[i], chain[i-1]
		if block.NumberU64() != prev.NumberU64()+1 || block.ParentHash() != prev.Hash() {
			// Chain broke ancestry, log a messge (programming error) and skip insertion
			log.Error("Non contiguous block insert",
				"number", block.Number(),
				"hash", block.Hash(),
				"parent", block.ParentHash(),
				"prevnumber", prev.Number(),
				"prevhash", prev.Hash())

			return 0, fmt.Errorf("non contiguous insert: item %d is #%d [%x..], item %d is #%d [%x..] (parent [%x..])", i-1, prev.NumberU64(),
				prev.Hash().Bytes()[:4], i, block.NumberU64(), block.Hash().Bytes()[:4], block.ParentHash().Bytes()[:4])
		}
	}

	// Pre-check passed, start the full block imports.
	if !bc.chainmu.TryLock() {
		return 0, errChainStopped
	}
	defer bc.chainmu.Unlock()
	n, events, logs, err := bc.insertChain(chain, true)
	bc.PostChainEvents(events, logs)
	return n, err
}

// insertChain is the internal implementation of InsertChain, which assumes that
// 1) chains are contiguous, and 2) The chain mutex is held.
//
// This method is split out so that import batches that require re-injecting
// historical blocks can do so without releasing the lock, which could lead to
// racey behaviour. If a sidechain import is in progress, and the historic state
// is imported, but then new canon-head is added before the actual sidechain
// completes, then the historic state could be pruned again
func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, []interface{}, []*types.Log, error) {
	// If the chain is terminating, don't even bother starting up.
	if bc.insertStopped() {
		return 0, nil, nil, nil
	}

	// Start a parallel signature recovery (signer will fluke on fork transition, minimal perf loss)
	SenderCacher.RecoverFromBlocks(types.MakeSigner(bc.chainConfig, chain[0].Number()), chain)

	// A queued approach to delivering events. This is generally
	// faster than direct delivery and requires much less mutex
	// acquiring.
	var (
		stats         = insertStats{startTime: mclock.Now()}
		events        = make([]interface{}, 0, len(chain))
		lastCanon     *types.Block
		coalescedLogs []*types.Log
	)
	// Start the parallel header verifier
	headers := make([]*types.Header, len(chain))
	seals := make([]bool, len(chain))

	for i, block := range chain {
		headers[i] = block.Header()
		seals[i] = verifySeals
		bc.downloadingBlock.Add(block.Hash(), struct{}{})
	}
	abort, results := bc.engine.VerifyHeaders(bc, headers, seals)
	defer close(abort)

	// Peek the error for the first block to decide the directing import logic
	it := newInsertIterator(chain, results, bc.validator)

	block, err := it.next()
	switch {
	// First block is pruned, insert as sidechain and reorg only if TD grows enough
	case err == consensus.ErrPrunedAncestor:
		return bc.insertSidechain(block, it)

	// First block is future, shove it (and all children) to the future queue (unknown ancestor)
	case err == consensus.ErrFutureBlock || (err == consensus.ErrUnknownAncestor && bc.futureBlocks.Contains(it.first().ParentHash())):
		for block != nil && (it.index == 0 || err == consensus.ErrUnknownAncestor) {
			if err := bc.addFutureBlock(block); err != nil {
				return it.index, events, coalescedLogs, err
			}
			block, err = it.next()
		}
		stats.queued += it.processed()
		stats.ignored += it.remaining()

		// If there are any still remaining, mark as ignored
		return it.index, events, coalescedLogs, err

	// First block (and state) is known
	//   1. We did a roll-back, and should now do a re-import
	//   2. The block is stored as a sidechain, and is lying about it's stateroot, and passes a stateroot
	// 	    from the canonical chain, which has not been verified.
	case err == ErrKnownBlock:
		// Skip all known blocks that behind us
		current := bc.CurrentBlock().NumberU64()

		for block != nil && err == ErrKnownBlock && current >= block.NumberU64() {
			stats.ignored++
			block, err = it.next()
		}
		// Falls through to the block import

	// Some other error occurred, abort
	case err != nil:
		stats.ignored += len(it.chain)
		bc.reportBlock(block, nil, err)
		return it.index, events, coalescedLogs, err
	}

	// No validation errors for the first block (or chain prefix skipped)
	for ; block != nil && err == nil; block, err = it.next() {
		// If the chain is terminating, stop processing blocks
		if bc.insertStopped() {
			log.Debug("Premature abort during blocks processing")
			break
		}
		// If the header is a banned one, straight out abort
		if BadHashes[block.Hash()] {
			bc.reportBlock(block, nil, ErrBlacklistedHash)
			return it.index, events, coalescedLogs, ErrBlacklistedHash
		}
		// Retrieve the parent block and it's state to execute on top
		start := time.Now()
		parent := it.previous()
		if parent == nil {
			parent = bc.GetHeader(block.ParentHash(), block.NumberU64()-1)
		}
		// Create a new statedb using the parent block and report an error if it fails.
		statedb, err := state.New(parent.Root, bc.stateCache)
		if err != nil {
			return it.index, events, coalescedLogs, err
		}
		statedb.SetLogger(bc.logger)

		// If we have a followup block, run that against the current state to pre-cache
		// transactions and probabilistically some of the account/storage trie nodes.
		var followupInterrupt atomic.Bool
		if bc.cacheConfig.TrieCleanPrefetch {
			if followup, err := it.peek(); followup != nil && err == nil {
				throwaway, _ := state.New(parent.Root, bc.stateCache)

				go func(start time.Time, followup *types.Block, throwaway *state.StateDB, interrupt *atomic.Bool) {
					// Disable tracing for prefetcher executions.
					vmCfg := bc.vmConfig
					vmCfg.Tracer = nil
					bc.prefetcher.Prefetch(followup, throwaway, vmCfg, interrupt)

					blockPrefetchExecuteTimer.Update(time.Since(start))
					if interrupt.Load() {
						blockPrefetchInterruptMeter.Mark(1)
					}
				}(time.Now(), followup, throwaway, &followupInterrupt)
			}
		}

		// The traced section of block import.
		res, err := bc.processBlock(block, parent, statedb)
		followupInterrupt.Store(true)
		if err != nil {
			return it.index, events, coalescedLogs, err
		}
		// Report the import stats before returning the various results
		stats.processed++
		stats.usedGas += res.usedGas

		switch res.status {
		case CanonStatTy:
			log.Debug("Inserted new block from downloader", "number", block.Number(), "hash", block.Hash(), "uncles", len(block.Uncles()),
				"txs", len(block.Transactions()), "gas", block.GasUsed(), "elapsed", common.PrettyDuration(time.Since(start)))

			coalescedLogs = append(coalescedLogs, res.logs...)
			events = append(events, ChainEvent{block, block.Hash(), res.logs})
			lastCanon = block

			// Only count canonical blocks for GC processing time
			bc.gcproc += res.procTime
			bc.UpdateBlocksHashCache(block)
		case SideStatTy:
			log.Debug("Inserted forked block from downloader", "number", block.Number(), "hash", block.Hash(), "diff", block.Difficulty(), "elapsed",
				common.PrettyDuration(time.Since(start)), "txs", len(block.Transactions()), "gas", block.GasUsed(), "uncles", len(block.Uncles()))
			events = append(events, ChainSideEvent{block})
			bc.UpdateBlocksHashCache(block)
		}

		dirty, _ := bc.triedb.Size()
		stats.report(chain, it.index, dirty)
		if bc.chainConfig.XDPoS != nil {
			engine, _ := bc.Engine().(*XDPoS.XDPoS)
			isEpochSwithBlock, _, err := engine.IsEpochSwitch(block.Header()) // epoch block
			if err != nil {
				log.Error("[insertChain] Error while checking and notifying channel CheckpointCh if the incoming block is epoch switch block", "Hash", block.Hash(), "Number", block.Number())
				bc.reportBlock(block, nil, err)
			}
			if isEpochSwithBlock {
				CheckpointCh <- 1
			}
		}
	}

	// Any blocks remaining here? The only ones we care about are the future ones
	if block != nil && err == consensus.ErrFutureBlock {
		if err := bc.addFutureBlock(block); err != nil {
			return it.index, events, coalescedLogs, err
		}
		block, err = it.next()

		for ; block != nil && err == consensus.ErrUnknownAncestor; block, err = it.next() {
			if err := bc.addFutureBlock(block); err != nil {
				return it.index, events, coalescedLogs, err
			}
			stats.queued++
		}
	}
	stats.ignored += it.remaining()

	// Append a single chain head event if we've progressed the chain
	if lastCanon != nil && bc.CurrentBlock().Hash() == lastCanon.Hash() {
		log.Debug("New ChainHeadEvent ", "number", lastCanon.NumberU64(), "hash", lastCanon.Hash())
		events = append(events, ChainHeadEvent{lastCanon})
	}
	return it.index, events, coalescedLogs, nil
}

// blockProcessingResult is a summary of block processing
// used for updating the stats.
type blockProcessingResult struct {
	usedGas  uint64
	procTime time.Duration
	status   WriteStatus
	logs     []*types.Log
}

// processBlock executes and validates the given block. If there was no error
// it writes the block and associated state to database.
func (bc *BlockChain) processBlock(block *types.Block, parent *types.Header, statedb *state.StateDB) (_ *blockProcessingResult, blockEndErr error) {
	var (
		err       error
		startTime = time.Now()
	)
	// TODO(daniel): implement CurrentFinalBlock() and CurrentSafeBlock(), ref PR #29189
	if bc.logger != nil && bc.logger.OnBlockStart != nil {
		td := bc.GetTd(block.ParentHash(), block.NumberU64()-1)
		bc.logger.OnBlockStart(tracing.BlockEvent{
			Block: block,
			TD:    td,
			// Finalized: bc.CurrentFinalBlock(),
			// Safe:      bc.CurrentSafeBlock(),
		})
	}
	if bc.logger != nil && bc.logger.OnBlockEnd != nil {
		defer func() {
			bc.logger.OnBlockEnd(blockEndErr)
		}()
	}

	// Process block using the parent state as reference point.
	pstart := time.Now()
	isTIPXDCXReceiver := bc.Config().IsTIPXDCXReceiver(block.Number())
	tradingState, lendingState, err := bc.processTradingAndLendingStates(isTIPXDCXReceiver, block, parent, statedb)
	if err != nil {
		bc.reportBlock(block, nil, err)
		return nil, err
	}
	feeCapacity := statedb.GetTRC21FeeCapacityFromStateWithCache(parent.Root)
	receipts, logs, usedGas, err := bc.processor.Process(block, statedb, tradingState, bc.vmConfig, feeCapacity)
	if err != nil {
		bc.reportBlock(block, receipts, err)
		return nil, err
	}
	ptime := time.Since(pstart)

	vstart := time.Now()
	// Validate the state using the default validator
	err = bc.validator.ValidateState(block, statedb, receipts, usedGas)
	if err != nil {
		bc.reportBlock(block, receipts, err)
		return nil, err
	}
	vtime := time.Since(vstart)
	proctime := time.Since(startTime) // processing + validation

	// Update the metrics touched during block processing and validation
	accountReadTimer.Update(statedb.AccountReads)                                     // Account reads are complete(in processing)
	storageReadTimer.Update(statedb.StorageReads)                                     // Storage reads are complete(in processing)
	accountUpdateTimer.Update(statedb.AccountUpdates)                                 // Account updates are complete(in validation)
	storageUpdateTimer.Update(statedb.StorageUpdates)                                 // Storage updates are complete(in validation)
	accountHashTimer.Update(statedb.AccountHashes)                                    // Account hashes are complete(in validation)
	storageHashTimer.Update(statedb.StorageHashes)                                    // Storage hashes are complete(in validation)
	triedbCommitTimer.Update(statedb.TrieDBCommits)                                   // Triedb commits are complete, we can mark them
	triehash := statedb.AccountHashes + statedb.StorageHashes                         // The time spent on tries hashing
	trieUpdate := statedb.AccountUpdates + statedb.StorageUpdates                     // The time spent on tries update
	blockExecutionTimer.Update(ptime - (statedb.AccountReads + statedb.StorageReads)) // The time spent on EVM processing
	blockValidationTimer.Update(vtime - (triehash + trieUpdate))                      // The time spent on block validation

	// Write the block to the chain and get the status.
	var (
		wstart = time.Now()
		status WriteStatus
	)
	status, err = bc.writeBlockWithState(block, receipts, statedb, tradingState, lendingState)
	if err != nil {
		return nil, err
	}
	// Update the metrics touched during block commit
	accountCommitTimer.Update(statedb.AccountCommits) // Account commits are complete, we can mark them
	storageCommitTimer.Update(statedb.StorageCommits) // Storage commits are complete, we can mark them

	blockWriteTimer.Update(time.Since(wstart) - statedb.AccountCommits - statedb.StorageCommits)
	elapsed := time.Since(startTime) + 1 // prevent zero division
	blockInsertTimer.Update(elapsed)

	return &blockProcessingResult{usedGas: usedGas, procTime: proctime, status: status, logs: logs}, nil
}

// insertSidechain is called when an import batch hits upon a pruned ancestor
// error, which happens when a sidechain with a sufficiently old fork-block is
// found.
//
// The method writes all (header-and-body-valid) blocks to disk, then tries to
// switch over to the new chain if the TD exceeded the current chain.
func (bc *BlockChain) insertSidechain(block *types.Block, it *insertIterator) (int, []interface{}, []*types.Log, error) {
	var (
		externTd *big.Int
		current  = bc.CurrentBlock().NumberU64()
	)
	// The first sidechain block error is already verified to be ErrPrunedAncestor.
	// Since we don't import them here, we expect ErrUnknownAncestor for the remaining
	// ones. Any other errors means that the block is invalid, and should not be written
	// to disk.
	err := consensus.ErrPrunedAncestor
	for ; block != nil && (err == consensus.ErrPrunedAncestor); block, err = it.next() {
		// Check the canonical state root for that number
		if number := block.NumberU64(); current >= number {
			if canonical := bc.GetBlockByNumber(number); canonical != nil && canonical.Root() == block.Root() {
				// This is most likely a shadow-state attack. When a fork is imported into the
				// database, and it eventually reaches a block height which is not pruned, we
				// just found that the state already exist! This means that the sidechain block
				// refers to a state which already exists in our canon chain.
				//
				// If left unchecked, we would now proceed importing the blocks, without actually
				// having verified the state of the previous blocks.
				log.Warn("Sidechain ghost-state attack detected", "number", block.NumberU64(), "sideroot", block.Root(), "canonroot", canonical.Root())

				// If someone legitimately side-mines blocks, they would still be imported as usual. However,
				// we cannot risk writing unverified blocks to disk when they obviously target the pruning
				// mechanism.
				return it.index, nil, nil, errors.New("sidechain ghost-state attack")
			}
		}
		if externTd == nil {
			externTd = bc.GetTd(block.ParentHash(), block.NumberU64()-1)
		}
		externTd = new(big.Int).Add(externTd, block.Difficulty())

		if !bc.HasBlock(block.Hash(), block.NumberU64()) {
			start := time.Now()
			if err := bc.writeBlockWithoutState(block, externTd); err != nil {
				return it.index, nil, nil, err
			}
			log.Debug("Inserted sidechain block", "number", block.Number(), "hash", block.Hash(),
				"diff", block.Difficulty(), "elapsed", common.PrettyDuration(time.Since(start)),
				"txs", len(block.Transactions()), "gas", block.GasUsed(), "uncles", len(block.Uncles()),
				"root", block.Root())
		}
	}
	// At this point, we've written all sidechain blocks to database. Loop ended
	// either on some other error or all were processed. If there was some other
	// error, we can ignore the rest of those blocks.
	//
	// If the externTd was larger than our local TD, we now need to reimport the previous
	// blocks to regenerate the required state
	localTd := bc.GetTd(bc.CurrentBlock().Hash(), current)
	if localTd.Cmp(externTd) > 0 {
		log.Info("Sidechain written to disk", "start", it.first().NumberU64(), "end", it.previous().Number, "sidetd", externTd, "localtd", localTd)
		return it.index, nil, nil, err
	}
	// Gather all the sidechain hashes (full blocks may be memory heavy)
	var (
		hashes  []common.Hash
		numbers []uint64
	)
	parent := it.previous()
	for parent != nil && !bc.HasState(parent.Root) {
		hashes = append(hashes, parent.Hash())
		numbers = append(numbers, parent.Number.Uint64())

		parent = bc.GetHeader(parent.ParentHash, parent.Number.Uint64()-1)
	}
	if parent == nil {
		return it.index, nil, nil, errors.New("missing parent")
	}
	// Import all the pruned blocks to make the state available
	var (
		blocks []*types.Block
		memory common.StorageSize
	)
	for i := len(hashes) - 1; i >= 0; i-- {
		// Append the next block to our batch
		block := bc.GetBlock(hashes[i], numbers[i])

		blocks = append(blocks, block)
		memory += block.Size()

		// If memory use grew too large, import and continue. Sadly we need to discard
		// all raised events and logs from notifications since we're too heavy on the
		// memory here.
		if len(blocks) >= 2048 || memory > 64*1024*1024 {
			log.Info("Importing heavy sidechain segment", "blocks", len(blocks), "start", blocks[0].NumberU64(), "end", block.NumberU64())
			if _, _, _, err := bc.insertChain(blocks, false); err != nil {
				return 0, nil, nil, err
			}
			blocks, memory = blocks[:0], 0

			// If the chain is terminating, stop processing blocks
			if bc.insertStopped() {
				log.Debug("Abort during blocks processing")
				return 0, nil, nil, nil
			}
		}
	}
	if len(blocks) > 0 {
		log.Info("Importing sidechain segment", "start", blocks[0].NumberU64(), "end", blocks[len(blocks)-1].NumberU64())
		return bc.insertChain(blocks, false)
	}
	return 0, nil, nil, nil
}

func (bc *BlockChain) InsertBlock(block *types.Block) error {
	events, logs, err := bc.insertBlock(block)
	bc.PostChainEvents(events, logs)
	return err
}

func (bc *BlockChain) PrepareBlock(block *types.Block) (err error) {
	defer log.Debug("Done prepare block ", "number", block.NumberU64(), "hash", block.Hash(), "validator", block.Header().Validator, "err", err)
	if _, ok := bc.resultProcess.Get(block.Hash()); ok {
		log.Debug("Stop prepare a block because the result cached", "number", block.NumberU64(), "hash", block.Hash(), "validator", block.Header().Validator)
		return nil
	}
	if _, ok := bc.calculatingBlock.Get(block.Hash()); ok {
		log.Debug("Stop prepare a block because inserting", "number", block.NumberU64(), "hash", block.Hash(), "validator", block.Header().Validator)
		return nil
	}
	err = bc.engine.VerifyHeader(bc, block.Header(), false)
	if err != nil {
		return err
	}
	result, err := bc.getResultBlock(block, false)
	switch err {
	case nil:
		bc.resultProcess.Add(block.Hash(), result)
		return nil
	case ErrKnownBlock:
		return nil
	case ErrStopPreparingBlock:
		log.Debug("Stop prepare a block because calculating", "number", block.NumberU64(), "hash", block.Hash(), "validator", block.Header().Validator)
		return nil
	default:
		return err
	}
}

func (bc *BlockChain) getResultBlock(block *types.Block, verifiedM2 bool) (*ResultProcessBlock, error) {
	var calculatedBlock *CalculatedBlock
	if verifiedM2 {
		if result, ok := bc.resultProcess.Get(block.HashNoValidator()); ok {
			log.Debug("Get result block from cache ", "number", block.NumberU64(), "hash", block.Hash(), "hash no validator", block.HashNoValidator())
			return result, nil
		}
		log.Debug("Not found cache prepare block ", "number", block.NumberU64(), "hash", block.Hash(), "validator", block.HashNoValidator())
		if calculatedBlock, _ := bc.calculatingBlock.Get(block.HashNoValidator()); calculatedBlock != nil {
			calculatedBlock.stop = true
		}
	}
	calculatedBlock = &CalculatedBlock{block, false}
	bc.calculatingBlock.Add(block.HashNoValidator(), calculatedBlock)
	// Start the parallel header verifier
	// If the chain is terminating, stop processing blocks
	if bc.insertStopped() {
		log.Debug("Premature abort during blocks processing")
		return nil, ErrBlacklistedHash
	}
	// If the header is a banned one, straight out abort
	if BadHashes[block.Hash()] {
		bc.reportBlock(block, nil, ErrBlacklistedHash)
		return nil, ErrBlacklistedHash
	}
	// Wait for the block's verification to complete
	bstart := time.Now()
	err := bc.validator.ValidateBody(block)
	switch {
	case err == ErrKnownBlock:
		// Block and state both already known. However if the current block is below
		// this number we did a rollback and we should reimport it nonetheless.
		if bc.CurrentBlock().NumberU64() >= block.NumberU64() {
			return nil, ErrKnownBlock
		}
	case err == consensus.ErrPrunedAncestor:
		// Block competing with the canonical chain, store in the db, but don't process
		// until the competitor TD goes above the canonical TD
		currentBlock := bc.CurrentBlock()
		localTd := bc.GetTd(currentBlock.Hash(), currentBlock.NumberU64())
		externTd := new(big.Int).Add(bc.GetTd(block.ParentHash(), block.NumberU64()-1), block.Difficulty())
		if localTd.Cmp(externTd) > 0 {
			return nil, err
		}
		// Competitor chain beat canonical, gather all blocks from the common ancestor
		var winner []*types.Block

		parent := bc.GetBlock(block.ParentHash(), block.NumberU64()-1)
		if parent == nil {
			return nil, fmt.Errorf("fail to get parent block at number: %v, hash: %v", block.NumberU64()-1, block.ParentHash())
		}
		for !bc.HasFullState(parent) {
			winner = append(winner, parent)
			parent = bc.GetBlock(parent.ParentHash(), parent.NumberU64()-1)
		}
		// fix issue #1765, return at once if winner is empty
		if len(winner) == 0 {
			return nil, errors.New("winner is empty")
		}
		for j := 0; j < len(winner)/2; j++ {
			winner[j], winner[len(winner)-1-j] = winner[len(winner)-1-j], winner[j]
		}
		log.Debug("Number block need calculated again", "number", block.NumberU64(), "hash", block.Hash().Hex(), "winners", len(winner))
		// Import all the pruned blocks to make the state available
		// During reorg, we use verifySeals=false
		_, _, _, err := bc.insertChain(winner, false)
		if err != nil {
			return nil, err
		}
	case err != nil:
		bc.reportBlock(block, nil, err)
		return nil, err
	}
	var parent = bc.GetHeader(block.ParentHash(), block.NumberU64()-1)
	// Create a new statedb using the parent block and report an error if it fails.
	statedb, err := state.New(parent.Root, bc.stateCache)
	if err != nil {
		return nil, err
	}
	// Process block using the parent state as reference point.
	isTIPXDCX := bc.Config().IsTIPXDCX(block.Number())
	tradingState, lendingState, err := bc.processTradingAndLendingStates(isTIPXDCX, block, parent, statedb)
	if err != nil {
		bc.reportBlock(block, nil, err)
		return nil, err
	}
	feeCapacity := statedb.GetTRC21FeeCapacityFromStateWithCache(parent.Root)
	receipts, logs, usedGas, err := bc.processor.ProcessBlockNoValidator(calculatedBlock, statedb, tradingState, bc.vmConfig, feeCapacity)
	process := time.Since(bstart)
	if err != nil {
		if err != ErrStopPreparingBlock {
			bc.reportBlock(block, receipts, err)
		}
		return nil, err
	}
	// Validate the state using the default validator
	err = bc.Validator().ValidateState(block, statedb, receipts, usedGas)
	if err != nil {
		bc.reportBlock(block, receipts, err)
		return nil, err
	}
	proctime := time.Since(bstart)
	log.Debug("Calculate new block", "number", block.Number(), "hash", block.Hash(), "uncles", len(block.Uncles()),
		"txs", len(block.Transactions()), "gas", block.GasUsed(), "elapsed", common.PrettyDuration(time.Since(bstart)), "process", process)
	return &ResultProcessBlock{receipts: receipts, logs: logs, state: statedb, tradingState: tradingState, lendingState: lendingState, proctime: proctime, usedGas: usedGas}, nil
}

// UpdateBlocksHashCache update BlocksHashCache by block number
func (bc *BlockChain) UpdateBlocksHashCache(block *types.Block) []common.Hash {
	blockNumber := block.Number().Uint64()
	cached, ok := bc.blocksHashCache.Get(blockNumber)

	if ok {
		hashArr := cached
		hashArr = append(hashArr, block.Hash())
		bc.blocksHashCache.Remove(blockNumber)
		bc.blocksHashCache.Add(blockNumber, hashArr)
		return hashArr
	}

	hashArr := []common.Hash{
		block.Hash(),
	}
	bc.blocksHashCache.Add(blockNumber, hashArr)
	return hashArr
}

// insertChain will execute the actual chain insertion and event aggregation. The
// only reason this method exists as a separate one is to make locking cleaner
// with deferred statements.
func (bc *BlockChain) insertBlock(block *types.Block) ([]interface{}, []*types.Log, error) {
	var (
		stats         = insertStats{startTime: mclock.Now()}
		events        = make([]interface{}, 0, 1)
		coalescedLogs []*types.Log
	)
	if _, ok := bc.downloadingBlock.Get(block.Hash()); ok {
		log.Debug("Stop fetcher a block because downloading", "number", block.NumberU64(), "hash", block.Hash())
		return events, coalescedLogs, nil
	}
	result, err := bc.getResultBlock(block, true)
	if err != nil {
		return events, coalescedLogs, err
	}
	defer bc.resultProcess.Remove(block.HashNoValidator())
	bc.wg.Add(1)
	defer bc.wg.Done()
	// Write the block to the chain and get the status.
	if !bc.chainmu.TryLock() {
		return nil, nil, errChainStopped
	}
	defer bc.chainmu.Unlock()
	if bc.HasBlockAndFullState(block.Hash(), block.NumberU64()) {
		return events, coalescedLogs, nil
	}
	status, err := bc.writeBlockWithState(block, result.receipts, result.state, result.tradingState, result.lendingState)

	if err != nil {
		return events, coalescedLogs, err
	}
	switch status {
	case CanonStatTy:
		log.Debug("Inserted new block from fetcher", "number", block.Number(), "hash", block.Hash(), "uncles", len(block.Uncles()),
			"txs", len(block.Transactions()), "gas", block.GasUsed(), "elapsed", common.PrettyDuration(time.Since(block.ReceivedAt)))
		coalescedLogs = append(coalescedLogs, result.logs...)
		events = append(events, ChainEvent{block, block.Hash(), result.logs})
		// Only count canonical blocks for GC processing time
		bc.gcproc += result.proctime
		bc.UpdateBlocksHashCache(block)
	case SideStatTy:
		log.Debug("Inserted forked block from fetcher", "number", block.Number(), "hash", block.Hash(), "diff", block.Difficulty(), "elapsed",
			common.PrettyDuration(time.Since(block.ReceivedAt)), "txs", len(block.Transactions()), "gas", block.GasUsed(), "uncles", len(block.Uncles()))
		blockInsertTimer.Update(result.proctime)
		events = append(events, ChainSideEvent{block})
		bc.UpdateBlocksHashCache(block)
	}
	stats.processed++
	stats.usedGas += result.usedGas
	dirty, _ := bc.triedb.Size()
	stats.report(types.Blocks{block}, 0, dirty)
	if bc.chainConfig.XDPoS != nil {
		// epoch block
		isEpochSwithBlock, _, err := bc.Engine().(*XDPoS.XDPoS).IsEpochSwitch(block.Header())
		if err != nil {
			log.Error("[insertBlock] Error while checking if the incoming block is epoch switch block", "Hash", block.Hash(), "Number", block.Number())
			bc.reportBlock(block, nil, err)
		}
		if isEpochSwithBlock {
			CheckpointCh <- 1
		}
	}
	// Append a single chain head event if we've progressed the chain
	if status == CanonStatTy && bc.CurrentBlock().Hash() == block.Hash() {
		events = append(events, ChainHeadEvent{block})
		log.Debug("New ChainHeadEvent from fetcher ", "number", block.NumberU64(), "hash", block.Hash())
	}
	return events, coalescedLogs, nil
}

// collectLogs collects the logs that were generated or removed during
// the processing of a block. These logs are later announced as deleted or reborn.
func (bc *BlockChain) collectLogs(b *types.Block, removed bool) []*types.Log {
	receipts := rawdb.ReadRawReceipts(bc.db, b.Hash(), b.NumberU64())
	if err := receipts.DeriveFields(bc.chainConfig, b.Hash(), b.NumberU64(), b.BaseFee(), b.Transactions()); err != nil {
		log.Error("Failed to derive block receipts fields", "hash", b.Hash(), "number", b.NumberU64(), "err", err)
	}

	var logs []*types.Log
	for _, receipt := range receipts {
		for _, log := range receipt.Logs {
			if removed {
				log.Removed = true
			}
			logs = append(logs, log)
		}
	}
	return logs
}

// reorg takes two blocks, an old chain and a new chain and will reconstruct the
// blocks and inserts them to be part of the new canonical chain and accumulates
// potential missing transactions and post an event about them.
func (bc *BlockChain) reorg(oldHead, newHead *types.Header) error {
	log.Warn("Reorg", "OldHash", oldHead.Hash().Hex(), "OldNum", oldHead.Number, "NewHash", newHead.Hash().Hex(), "NewNum", newHead.Number)

	var (
		newChain    []*types.Header
		oldChain    []*types.Header
		commonBlock *types.Header
	)

	// Reduce the longer chain to the same number as the shorter one
	if oldHead.Number.Uint64() > newHead.Number.Uint64() {
		// Old chain is longer, gather all transactions and logs as deleted ones
		for ; oldHead != nil && oldHead.Number.Uint64() != newHead.Number.Uint64(); oldHead = bc.GetHeader(oldHead.ParentHash, oldHead.Number.Uint64()-1) {
			oldChain = append(oldChain, oldHead)
		}
	} else {
		// New chain is longer, stash all blocks away for subsequent insertion
		for ; newHead != nil && newHead.Number.Uint64() != oldHead.Number.Uint64(); newHead = bc.GetHeader(newHead.ParentHash, newHead.Number.Uint64()-1) {
			newChain = append(newChain, newHead)
		}
	}
	if oldHead == nil {
		return errInvalidOldChain
	}
	if newHead == nil {
		return errInvalidNewChain
	}

	// Both sides of the reorg are at the same number, reduce both until the common
	// ancestor is found
	for {
		// If the common ancestor was found, bail out
		if oldHead.Hash() == newHead.Hash() {
			commonBlock = oldHead
			break
		}
		// Remove an old block as well as stash away a new block
		oldChain = append(oldChain, oldHead)
		newChain = append(newChain, newHead)

		// Step back with both chains
		oldHead = bc.GetHeader(oldHead.ParentHash, oldHead.Number.Uint64()-1)
		if oldHead == nil {
			return errInvalidOldChain
		}
		newHead = bc.GetHeader(newHead.ParentHash, newHead.Number.Uint64()-1)
		if newHead == nil {
			return errInvalidNewChain
		}
	}

	// Ensure XDPoS engine committed block will be not reverted
	if xdpos, ok := bc.Engine().(*XDPoS.XDPoS); ok {
		latestCommittedBlock := xdpos.EngineV2.GetLatestCommittedBlockInfo()
		if latestCommittedBlock != nil {
			cmp := commonBlock.Number.Cmp(latestCommittedBlock.Number)
			if cmp < 0 {
				for _, oldBlock := range oldChain {
					if oldBlock.Number.Cmp(latestCommittedBlock.Number) == 0 {
						if oldBlock.Hash() != latestCommittedBlock.Hash {
							log.Error("Impossible reorg, please file an issue", "OldNum", oldBlock.Number, "OldHash", oldBlock.Hash().Hex(), "LatestCommittedHash", latestCommittedBlock.Hash.Hex())
						} else {
							log.Warn("Stop reorg, blockchain is under forking attack", "OldCommittedNum", oldBlock.Number, "OldCommittedHash", oldBlock.Hash().Hex())
							return fmt.Errorf("stop reorg, blockchain is under forking attack. OldCommitted num %d, hash %s", oldBlock.Number, oldBlock.Hash().Hex())
						}
					}
				}
			} else if cmp == 0 {
				if commonBlock.Hash() != latestCommittedBlock.Hash {
					log.Error("Impossible reorg, please file an issue", "OldNum", commonBlock.Number.Uint64(), "OldHash", commonBlock.Hash().Hex(), "LatestCommittedHash", latestCommittedBlock.Hash.Hex())
				}
			}
		}
	}

	// Ensure the user sees large reorgs
	if len(oldChain) > 0 && len(newChain) > 0 {
		logFn := log.Info
		msg := "Chain reorg detected"
		if len(oldChain) > 63 {
			msg = "Large chain reorg detected"
			logFn = log.Warn
		}
		logFn(msg, "number", commonBlock.Number, "hash", commonBlock.Hash().Hex(),
			"drop", len(oldChain), "dropfrom", oldChain[0].Hash().Hex(), "add", len(newChain), "addfrom", newChain[0].Hash().Hex())
		blockReorgAddMeter.Mark(int64(len(newChain)))
		blockReorgDropMeter.Mark(int64(len(oldChain)))
		blockReorgMeter.Mark(1)
	} else if len(newChain) > 0 {
		// Special case happens in the post merge stage that current head is
		// the ancestor of new head while these two blocks are not consecutive
		log.Info("Extend chain", "add", len(newChain), "number", newChain[0].Number, "hash", newChain[0].Hash())
		blockReorgAddMeter.Mark(int64(len(newChain)))
	} else {
		// len(newChain) == 0 && len(oldChain) > 0
		// rewind the canonical chain to a lower point.
		log.Error("Impossible reorg, please file an issue", "oldnum", oldHead.Number, "oldhash", oldHead.Hash(), "oldblocks", len(oldChain), "newnum", newHead.Number, "newhash", newHead.Hash(), "newblocks", len(newChain))
	}

	// Acquire the tx-lookup lock before mutation. This step is essential
	// as the txlookups should be changed atomically, and all subsequent
	// reads should be blocked until the mutation is complete.
	// bc.txLookupLock.Lock()

	// Reorg can be executed, start reducing the chain's old blocks and appending
	// the new blocks
	var (
		deletedTxs []common.Hash
		rebirthTxs []common.Hash

		deletedLogs []*types.Log
		rebirthLogs []*types.Log
	)

	// Deleted log emission on the API uses forward order, which is borked, but
	// we'll leave it in for legacy reasons.
	//
	// TODO(karalabe): This should be nuked out, no idea how, deprecate some APIs?
	{
		for i := len(oldChain) - 1; i >= 0; i-- {
			block := bc.GetBlock(oldChain[i].Hash(), oldChain[i].Number.Uint64())
			if block == nil {
				return errInvalidOldChain // Corrupt database, mostly here to avoid weird panics
			}
			if logs := bc.collectLogs(block, true); len(logs) > 0 {
				deletedLogs = append(deletedLogs, logs...)
			}
			if len(deletedLogs) > 512 {
				go bc.rmLogsFeed.Send(RemovedLogsEvent{deletedLogs})
				deletedLogs = nil
			}
			// TODO(daniel): remove chainSideFeed, reference PR #30601
			// Also send event for blocks removed from the canon chain.
			// bc.chainSideFeed.Send(ChainSideEvent{Block: block})
		}
		if len(deletedLogs) > 0 {
			go bc.rmLogsFeed.Send(RemovedLogsEvent{deletedLogs})
		}
	}

	// Undo old blocks in reverse order
	for i := 0; i < len(oldChain); i++ {
		// Collect all the deleted transactions
		block := bc.GetBlock(oldChain[i].Hash(), oldChain[i].Number.Uint64())
		if block == nil {
			return errInvalidOldChain // Corrupt database, mostly here to avoid weird panics
		}
		for _, tx := range block.Transactions() {
			deletedTxs = append(deletedTxs, tx.Hash())
		}
		// Collect deleted logs and emit them for new integrations
		// if logs := bc.collectLogs(block, true); len(logs) > 0 {
		// 	slices.Reverse(logs) // Emit revertals latest first, older then
		// }
	}

	// Apply new blocks in forward order
	for i := len(newChain) - 1; i >= 0; i-- {
		// Collect all the included transactions
		block := bc.GetBlock(newChain[i].Hash(), newChain[i].Number.Uint64())
		if block == nil {
			return errInvalidNewChain // Corrupt database, mostly here to avoid weird panics
		}
		for _, tx := range block.Transactions() {
			rebirthTxs = append(rebirthTxs, tx.Hash())
		}
		// Collect inserted logs and emit them
		if logs := bc.collectLogs(block, false); len(logs) > 0 {
			rebirthLogs = append(rebirthLogs, logs...)
		}
		if len(rebirthLogs) > 512 {
			bc.logsFeed.Send(rebirthLogs)
			rebirthLogs = nil
		}
		// Update the head block
		bc.writeHeadBlock(block, true)
		// prepare set of masternodes for the next epoch
		if bc.chainConfig.XDPoS != nil && ((block.NumberU64() % bc.chainConfig.XDPoS.Epoch) == (bc.chainConfig.XDPoS.Epoch - bc.chainConfig.XDPoS.Gap)) {
			if err := bc.UpdateM1(); err != nil {
				log.Crit("Fail to update masternodes during reorg", "number", block.Number, "hash", block.Hash().Hex(), "err", err)
			}
		}
	}
	if len(rebirthLogs) > 0 {
		bc.logsFeed.Send(rebirthLogs)
	}

	// Delete useless indexes right now which includes the non-canonical
	// transaction indexes, canonical chain indexes which above the head.
	batch := bc.db.NewBatch()
	for _, tx := range types.HashDifference(deletedTxs, rebirthTxs) {
		rawdb.DeleteTxLookupEntry(batch, tx)
	}
	// Delete all hash markers that are not part of the new canonical chain.
	// Because the reorg function handles new chain head, all hash
	// markers greater than new chain head should be deleted.
	number := commonBlock.Number
	if len(newChain) > 0 {
		number = newChain[0].Number
	}
	for i := number.Uint64() + 1; ; i++ {
		hash := rawdb.ReadCanonicalHash(bc.db, i)
		if hash == (common.Hash{}) {
			break
		}
		rawdb.DeleteCanonicalHash(batch, i)
	}
	if err := batch.Write(); err != nil {
		log.Crit("Failed to delete useless indexes", "err", err)
	}

	// Reset the tx lookup cache to clear stale txlookup cache.
	// bc.txLookupCache.Purge()

	// Release the tx-lookup lock after mutation.
	// bc.txLookupLock.Unlock()

	return nil
}

// PostChainEvents iterates over the events generated by a chain insertion and
// posts them into the event feed.
// TODO: Should not expose PostChainEvents. The chain events should be posted in WriteBlock.
func (bc *BlockChain) PostChainEvents(events []interface{}, logs []*types.Log) {
	// post event logs for further processing
	if logs != nil {
		bc.logsFeed.Send(logs)
	}
	for _, event := range events {
		switch ev := event.(type) {
		case ChainEvent:
			bc.chainFeed.Send(ev)

		case ChainHeadEvent:
			bc.chainHeadFeed.Send(ev)

		case ChainSideEvent:
			bc.chainSideFeed.Send(ev)
		}
	}
}

// futureBlocksLoop processes the 'future block' queue.
func (bc *BlockChain) futureBlocksLoop() {
	defer bc.wg.Done()

	futureTimer := time.NewTicker(100 * time.Millisecond)
	defer futureTimer.Stop()

	for {
		select {
		case <-futureTimer.C:
			bc.procFutureBlocks()
		case <-bc.quit:
			return
		}
	}
}

// reportBlock logs a bad block error.
func (bc *BlockChain) reportBlock(block *types.Block, receipts types.Receipts, err error) {
	rawdb.WriteBadBlock(bc.db, block)

	var roundNumber = types.Round(0)
	engine, ok := bc.Engine().(*XDPoS.XDPoS)
	if ok {
		var err error
		roundNumber, err = engine.EngineV2.GetRoundNumber(block.Header())
		if err != nil {
			log.Error("reportBlock", "GetRoundNumber", err)
		}
	}

	var receiptString string
	for i, receipt := range receipts {
		receiptString += fmt.Sprintf("\n  %d: cumulative: %v gas: %v contract: %v status: %v tx: %v logs: %v bloom: %x state: %x",
			i, receipt.CumulativeGasUsed, receipt.GasUsed, receipt.ContractAddress.Hex(),
			receipt.Status, receipt.TxHash.Hex(), receipt.Logs, receipt.Bloom, receipt.PostState)
	}
	log.Error(fmt.Sprintf(`
########## BAD BLOCK #########
Number: %v
Hash: %#x
Round: %v
Error: %v
%s
Receipts: %v
##############################
`, block.Number(), block.Hash(), roundNumber, err, bc.chainConfig.Description(), receiptString))
}

// InsertHeaderChain attempts to insert the given header chain in to the local
// chain, possibly creating a reorg. If an error is returned, it will return the
// index number of the failing header as well an error describing what went wrong.
//
// The verify parameter can be used to fine tune whether nonce verification
// should be done or not. The reason behind the optional check is because some
// of the header retrieval mechanisms already need to verify nonces, as well as
// because nonces can be verified sparsely, not needing to check each.
func (bc *BlockChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error) {
	start := time.Now()
	if i, err := bc.hc.ValidateHeaderChain(chain, checkFreq); err != nil {
		return i, err
	}

	if !bc.chainmu.TryLock() {
		return 0, errChainStopped
	}
	defer bc.chainmu.Unlock()

	whFunc := func(header *types.Header) error {
		_, err := bc.hc.WriteHeader(header)
		return err
	}

	return bc.hc.InsertHeaderChain(chain, whFunc, start)
}

// CurrentHeader retrieves the current head header of the canonical chain. The
// header is retrieved from the HeaderChain's internal cache.
func (bc *BlockChain) CurrentHeader() *types.Header {
	return bc.hc.CurrentHeader()
}

// GetTd retrieves a block's total difficulty in the canonical chain from the
// database by hash and number, caching it if found.
func (bc *BlockChain) GetTd(hash common.Hash, number uint64) *big.Int {
	return bc.hc.GetTd(hash, number)
}

// GetTdByHash retrieves a block's total difficulty in the canonical chain from the
// database by hash, caching it if found.
func (bc *BlockChain) GetTdByHash(hash common.Hash) *big.Int {
	return bc.hc.GetTdByHash(hash)
}

// GetHeader retrieves a block header from the database by hash and number,
// caching it if found.
func (bc *BlockChain) GetHeader(hash common.Hash, number uint64) *types.Header {
	return bc.hc.GetHeader(hash, number)
}

// GetHeaderByHash retrieves a block header from the database by hash, caching it if
// found.
func (bc *BlockChain) GetHeaderByHash(hash common.Hash) *types.Header {
	return bc.hc.GetHeaderByHash(hash)
}

// HasHeader checks if a block header is present in the database or not, caching
// it if present.
func (bc *BlockChain) HasHeader(hash common.Hash, number uint64) bool {
	return bc.hc.HasHeader(hash, number)
}

// GetCanonicalHash returns the canonical hash for a given block number
func (bc *BlockChain) GetCanonicalHash(number uint64) common.Hash {
	return bc.hc.GetCanonicalHash(number)
}

// GetBlockHashesFromHash retrieves a number of block hashes starting at a given
// hash, fetching towards the genesis block.
func (bc *BlockChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash {
	return bc.hc.GetBlockHashesFromHash(hash, max)
}

// GetHeaderByNumber retrieves a block header from the database by number,
// caching it (associated with its hash) if found.
func (bc *BlockChain) GetHeaderByNumber(number uint64) *types.Header {
	return bc.hc.GetHeaderByNumber(number)
}

// Set config for testing purpose function
func (bc *BlockChain) SetConfig(config *params.ChainConfig) {
	bc.chainConfig = config
}

// Config retrieves the blockchain's chain configuration.
func (bc *BlockChain) Config() *params.ChainConfig { return bc.chainConfig }

// Engine retrieves the blockchain's consensus engine.
func (bc *BlockChain) Engine() consensus.Engine { return bc.engine }

// SubscribeRemovedLogsEvent registers a subscription of RemovedLogsEvent.
func (bc *BlockChain) SubscribeRemovedLogsEvent(ch chan<- RemovedLogsEvent) event.Subscription {
	return bc.scope.Track(bc.rmLogsFeed.Subscribe(ch))
}

// SubscribeChainEvent registers a subscription of ChainEvent.
func (bc *BlockChain) SubscribeChainEvent(ch chan<- ChainEvent) event.Subscription {
	return bc.scope.Track(bc.chainFeed.Subscribe(ch))
}

// SubscribeChainHeadEvent registers a subscription of ChainHeadEvent.
func (bc *BlockChain) SubscribeChainHeadEvent(ch chan<- ChainHeadEvent) event.Subscription {
	return bc.scope.Track(bc.chainHeadFeed.Subscribe(ch))
}

// SubscribeChainSideEvent registers a subscription of ChainSideEvent.
func (bc *BlockChain) SubscribeChainSideEvent(ch chan<- ChainSideEvent) event.Subscription {
	return bc.scope.Track(bc.chainSideFeed.Subscribe(ch))
}

// SubscribeLogsEvent registers a subscription of []*types.Log.
func (bc *BlockChain) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription {
	return bc.scope.Track(bc.logsFeed.Subscribe(ch))
}

// Get current IPC Client.
func (bc *BlockChain) GetClient() (bind.ContractBackend, error) {
	if bc.Client == nil {
		// Inject ipc client global instance.
		client, err := ethclient.Dial(bc.IPCEndpoint)
		if err != nil {
			log.Error("Fail to connect IPC", "error", err)
			return nil, err
		}
		bc.Client = client
	}

	return bc.Client, nil
}

func (bc *BlockChain) UpdateM1() error {
	engine, ok := bc.Engine().(*XDPoS.XDPoS)
	if bc.Config().XDPoS == nil || !ok {
		return ErrNotXDPoS
	}
	log.Info("It's time to update new set of masternodes for the next epoch...")
	// get masternodes information from smart contract
	client, err := bc.GetClient()
	if err != nil {
		return fmt.Errorf("failed to get client: %w", err)
	}
	addr := common.MasternodeVotingSMCBinary
	validator, err := contractValidator.NewXDCValidator(addr, client)
	if err != nil {
		return fmt.Errorf("failed to create validator contract: %w", err)
	}
	opts := new(bind.CallOpts)

	var candidates []common.Address
	// get candidates from slot of stateDB
	// if can't get anything, request from contracts
	stateDB, err := bc.State()
	if err != nil {
		candidates, err = validator.GetCandidates(opts)
		if err != nil {
			return err
		}
	} else if stateDB == nil {
		return errors.New("nil stateDB in UpdateM1")
	} else {
		candidates = stateDB.GetCandidates()
	}

	var ms []utils.Masternode
	for _, candidate := range candidates {
		v, err := validator.GetCandidateCap(opts, candidate)
		if err != nil {
			return err
		}
		// TODO: smart contract shouldn't return "0x0000000000000000000000000000000000000000"
		if !candidate.IsZero() {
			ms = append(ms, utils.Masternode{Address: candidate, Stake: v})
		}
	}
	if len(ms) == 0 {
		log.Error("No masternode found. Stopping node")
		return errors.New("no masternode found")
	} else {
		sort.Slice(ms, func(i, j int) bool {
			return ms[i].Stake.Cmp(ms[j].Stake) >= 0
		})
		log.Info("Ordered list of masternode candidates")
		for _, m := range ms {
			log.Info("", "address", m.Address.String(), "stake", m.Stake)
		}
		// update masternodes

		log.Info("Updating new set of masternodes")
		// get block header
		header := bc.CurrentHeader()
		err = engine.UpdateMasternodes(bc, header, ms)
		if err != nil {
			return err
		}
		log.Info("Masternodes are ready for the next epoch")
	}
	return nil
}

func (bc *BlockChain) AddMatchingResult(txHash common.Hash, matchingResults map[common.Hash]tradingstate.MatchingResult) {
	for hash, result := range matchingResults {
		cacheKey := crypto.Keccak256Hash(txHash.Bytes(), hash.Bytes())
		bc.resultTrade.Add(cacheKey, result.Trades)
		bc.rejectedOrders.Add(cacheKey, result.Rejects)
	}
}

func (bc *BlockChain) AddLendingResult(txHash common.Hash, lendingResults map[common.Hash]lendingstate.MatchingResult) {
	for hash, result := range lendingResults {
		bc.resultLendingTrade.Add(crypto.Keccak256Hash(txHash.Bytes(), hash.Bytes()), result.Trades)
		bc.rejectedLendingItem.Add(crypto.Keccak256Hash(txHash.Bytes(), hash.Bytes()), result.Rejects)
	}
}

func (bc *BlockChain) AddFinalizedTrades(txHash common.Hash, trades map[common.Hash]*lendingstate.LendingTrade) {
	bc.finalizedTrade.Add(txHash, trades)
}

// processTradingAndLendingStates processes the trading and lending states for a given block in the blockchain.
//
// Parameters:
//   - isValidBlockNumber: A boolean indicating whether the block number is valid for processing trading and lending states.
//   - block: The current block being processed.
//   - parent: The parent block of the current block.
//   - statedb: The current state database for the blockchain.
//
// Returns:
//   - *tradingstate.TradingStateDB: The updated trading state database, if applicable.
//   - *lendingstate.LendingStateDB: The updated lending state database, if applicable.
//   - error: An error if any issues occur during processing.
//
// The function performs the following operations:
//  1. Validates if the block number is eligible for trading and lending state processing based on the blockchain configuration.
//  2. Retrieves the block author and validates the block header.
//  3. Fetches the trading and lending services from the consensus engine.
//  4. Retrieves the trading and lending states of the parent block.
//  5. Handles epoch switch logic, including updating medium prices for trading services if the block is an epoch switch block.
//  6. Validates trading and lending orders using the block's transactions and state.
//  7. Processes liquidation data for lending trades if the block is a liquidation block.
//  8. Verifies the integrity of the trading and lending state roots by comparing the computed roots with the expected roots.
func (bc *BlockChain) processTradingAndLendingStates(isValidBlockNumber bool, block *types.Block, parent *types.Header, statedb *state.StateDB) (*tradingstate.TradingStateDB, *lendingstate.LendingStateDB, error) {
	if !isValidBlockNumber || bc.chainConfig.XDPoS == nil || block.NumberU64() <= bc.chainConfig.XDPoS.Epoch {
		return nil, nil, nil
	}

	engine, _ := bc.Engine().(*XDPoS.XDPoS)
	if engine == nil {
		return nil, nil, nil
	}

	author, err := bc.Engine().Author(block.Header()) // Ignore error, we're past header validation
	if err != nil {
		return nil, nil, err
	}

	tradingService := engine.GetXDCXService()
	lendingService := engine.GetLendingService()
	if tradingService == nil || lendingService == nil {
		return nil, nil, nil
	}

	parentAuthor, _ := bc.Engine().Author(parent)
	parentBlock := bc.GetBlock(parent.Hash(), parent.Number.Uint64())
	tradingState, err := tradingService.GetTradingState(parentBlock, parentAuthor)
	if err != nil {
		return nil, nil, err
	}
	lendingState, err := lendingService.GetLendingState(parentBlock, parentAuthor)
	if err != nil {
		return nil, nil, err
	}

	isEpochSwithBlock, epochNumber, err := engine.IsEpochSwitch(block.Header())
	if err != nil {
		log.Error("[insertChain] Error while checking if the incoming block is epoch switch block", "Hash", block.Hash(), "Number", block.Number())
		return tradingState, lendingState, err
	}

	if isEpochSwithBlock {
		if err := tradingService.UpdateMediumPriceBeforeEpoch(epochNumber, tradingState, statedb); err != nil {
			return tradingState, lendingState, err
		}
	} else {
		txMatchBatchData, err := ExtractTradingTransactions(block.Transactions())
		if err != nil {
			return tradingState, lendingState, err
		}
		for _, txMatchBatch := range txMatchBatchData {
			log.Debug("Verify matching transaction", "txHash", txMatchBatch.TxHash.Hex())
			err := bc.validator.ValidateTradingOrder(statedb, tradingState, txMatchBatch, author, block.Header())
			if err != nil {
				return tradingState, lendingState, err
			}
		}
		batches, err := ExtractLendingTransactions(block.Transactions())
		if err != nil {
			return tradingState, lendingState, err
		}
		for _, batch := range batches {
			log.Debug("Verify matching transaction", "txHash", batch.TxHash.Hex())
			err := bc.validator.ValidateLendingOrder(statedb, lendingState, tradingState, batch, author, block.Header())
			if err != nil {
				return tradingState, lendingState, err
			}
		}
		// liquidate / finalize open lendingTrades
		if block.Number().Uint64()%bc.chainConfig.XDPoS.Epoch == common.LiquidateLendingTradeBlock {
			_, _, _, _, _, err := lendingService.ProcessLiquidationData(block.Header(), bc, statedb, tradingState, lendingState)
			if err != nil {
				return tradingState, lendingState, fmt.Errorf("failed to ProcessLiquidationData. Err: %v", err)
			}
		}
	}

	if tradingState != nil {
		gotRoot := tradingState.IntermediateRoot()
		expectRoot, _ := tradingService.GetTradingStateRoot(block, author)
		parentRoot, _ := tradingService.GetTradingStateRoot(parentBlock, parentAuthor)
		if gotRoot != expectRoot {
			err = fmt.Errorf("invalid XDCx trading state merke trie got : %s , expect : %s ,parent : %s", gotRoot.Hex(), expectRoot.Hex(), parentRoot.Hex())
			return tradingState, lendingState, err
		}
		log.Debug("XDCX Trading State Root", "number", block.NumberU64(), "parent", parentRoot.Hex(), "nextRoot", expectRoot.Hex())
	}

	if lendingState != nil && tradingState != nil {
		gotRoot := lendingState.IntermediateRoot()
		expectRoot, _ := lendingService.GetLendingStateRoot(block, author)
		parentRoot, _ := lendingService.GetLendingStateRoot(parentBlock, parentAuthor)
		if gotRoot != expectRoot {
			err = fmt.Errorf("invalid lending state merke trie got: %s, expect: %s, parent: %s", gotRoot.Hex(), expectRoot.Hex(), parentRoot.Hex())
			return tradingState, lendingState, err
		}
		log.Debug("XDCX Lending State Root", "number", block.NumberU64(), "parent", parentRoot.Hex(), "nextRoot", expectRoot.Hex())
	}

	return tradingState, lendingState, nil
}