var Defaults = Config{
	HistoryMode:        history.KeepAll,
	SyncMode:           SnapSync,
	NetworkId:          0,
	TxLookupLimit:      2350000,
	TransactionHistory: 2350000,
	LogHistory:         2350000,
	StateHistory:       params.FullImmutabilityThreshold,
	DatabaseCache:      512,
	TrieCleanCache:     154,
	TrieDirtyCache:     256,
	TrieTimeout:        60 * time.Minute,
	SnapshotCache:      102,
	FilterLogCacheSize: 32,
	Miner:              miner.DefaultConfig,
	TxPool:             legacypool.DefaultConfig,
	BlobPool:           blobpool.DefaultConfig,
	RPCGasCap:          50000000,
	RPCEVMTimeout:      5 * time.Second,
	GPO:                FullNodeGPO,
	RPCTxFeeCap:        1,
}

var FullNodeGPO = gasprice.Config{
	Blocks:           20,
	Percentile:       60,
	MaxHeaderHistory: 1024,
	MaxBlockHistory:  1024,
	MaxPrice:         gasprice.DefaultMaxPrice,
	IgnorePrice:      gasprice.DefaultIgnorePrice,
}

type Config struct {
	// The genesis block, which is inserted if the database is empty.
	// If nil, the Ethereum main net block is used.
	Genesis *core.Genesis `toml:",omitempty"`

	// Network ID separates blockchains on the peer-to-peer networking level. When left
	// zero, the chain ID is used as network ID.
	NetworkId uint64
	SyncMode  SyncMode

	// HistoryMode configures chain history retention.
	HistoryMode history.HistoryMode

	// This can be set to list of enrtree:// URLs which will be queried for
	// nodes to connect to.
	EthDiscoveryURLs  []string
	SnapDiscoveryURLs []string

	// State options.
	NoPruning  bool // Whether to disable pruning and flush everything to disk
	NoPrefetch bool // Whether to disable prefetching and only load state on demand

	// Deprecated: use 'TransactionHistory' instead.
	TxLookupLimit uint64 `toml:",omitempty"` // The maximum number of blocks from head whose tx indices are reserved.

	TransactionHistory   uint64 `toml:",omitempty"` // The maximum number of blocks from head whose tx indices are reserved.
	LogHistory           uint64 `toml:",omitempty"` // The maximum number of blocks from head where a log search index is maintained.
	LogNoHistory         bool   `toml:",omitempty"` // No log search index is maintained.
	LogExportCheckpoints string // export log index checkpoints to file
	StateHistory         uint64 `toml:",omitempty"` // The maximum number of blocks from head whose state histories are reserved.

	// State scheme represents the scheme used to store ethereum states and trie
	// nodes on top. It can be 'hash', 'path', or none which means use the scheme
	// consistent with persistent state.
	StateScheme string `toml:",omitempty"`

	// RequiredBlocks is a set of block number -> hash mappings which must be in the
	// canonical chain of all remote peers. Setting the option makes geth verify the
	// presence of these blocks for every new peer connection.
	RequiredBlocks map[uint64]common.Hash `toml:"-"`

	// Database options
	SkipBcVersionCheck bool `toml:"-"`
	DatabaseHandles    int  `toml:"-"`
	DatabaseCache      int
	DatabaseFreezer    string
	DatabaseEra        string

	TrieCleanCache int
	TrieDirtyCache int
	TrieTimeout    time.Duration
	SnapshotCache  int
	Preimages      bool

	// This is the number of blocks for which logs will be cached in the filter system.
	FilterLogCacheSize int

	// Mining options
	Miner miner.Config

	// Transaction pool options
	TxPool   legacypool.Config
	BlobPool blobpool.Config

	// Gas Price Oracle options
	GPO gasprice.Config

	// Enables tracking of SHA3 preimages in the VM
	EnablePreimageRecording bool

	// Enables VM tracing
	VMTrace           string
	VMTraceJsonConfig string

	// RPCGasCap is the global gas cap for eth-call variants.
	RPCGasCap uint64

	// RPCEVMTimeout is the global timeout for eth-call.
	RPCEVMTimeout time.Duration

	// RPCTxFeeCap is the global transaction fee (price * gas limit) cap for
	// send-transaction variants. The unit is ether.
	RPCTxFeeCap float64

	// OverrideOsaka (TODO: remove after the fork)
	OverrideOsaka *uint64 `toml:",omitempty"`

	// OverrideVerkle (TODO: remove after the fork)
	OverrideVerkle *uint64 `toml:",omitempty"`
}

type SyncMode uint32

const (
	FullSync SyncMode = iota // Synchronise the entire blockchain history from full blocks
	SnapSync                 // Download the chain and the state via compact snapshots
)