stores the encrypted crypto keys that encrypt all other generated keys

    stores the current sync state of the root manager.

            scopeBucketNme is the name of the top-level bucket within the
            hierarchy. It maps: purpose || coinType to a new sub-bucket that
            will house a scoped address manager. All buckets below are a child
            of this bucket:

            scopeBucket -> scope -> acctBucketName //account id=>dbDefaultAccountRow
            scopeBucket -> scope -> addrBucketName //addressID Hash=>dbAddressRow
            scopeBucket -> scope -> usedAddrBucketName // 一个地址是否被使用
            scopeBucket -> scope -> addrAcctIdxBucketName //addressID hash => account id
            scopeBucket -> scope -> acctNameIdxBucketName //accountName => account_id
            scopeBucket -> scope -> acctIDIdxBucketName //account_id => accountName
            scopeBucket -> scope -> metaBucket //metaData
            scopeBucket -> scope -> metaBucket -> lastAccountNameKey //manager中的最后一个account
            scopeBucket -> scope -> coinTypePrivKey //后面这两个代码没看到
            scopeBucket -> scope -> coinTypePubKey

scopeSchemaBucket is the name of the bucket that maps a particular
manager scope to the type of addresses that should be derived for
particular branches during key derivation.

	// KeyScopeBIP0049Plus is the key scope of our modified BIP0049
	// derivation. We say this is BIP0049 "plus", as we'll actually use
	// p2wkh change all change addresses.
	KeyScopeBIP0049Plus = KeyScope{
		Purpose: 49,
		Coin:    0,
	}

	// KeyScopeBIP0084 is the key scope for BIP0084 derivation. BIP0084
	// will be used to derive all p2wkh addresses.
	KeyScopeBIP0084 = KeyScope{
		Purpose: 84,
		Coin:    0,
	}

	// KeyScopeBIP0044 is the key scope for BIP0044 derivation. Legacy
	// wallets will only be able to use this key scope, and no keys beyond
	// it.
	KeyScopeBIP0044 = KeyScope{
		Purpose: 44,
		Coin:    0,
	}

	// DefaultKeyScopes is the set of default key scopes that will be
	// created by the root manager upon initial creation.
	DefaultKeyScopes = []KeyScope{
		KeyScopeBIP0049Plus,
		KeyScopeBIP0084,
		KeyScopeBIP0044,
	}

	// ScopeAddrMap is a map from the default key scopes to the scope
	// address schema for each scope type. This will be consulted during
	// the initial creation of the root key manager.
	ScopeAddrMap = map[KeyScope]ScopeAddrSchema{
		KeyScopeBIP0049Plus: {
			ExternalAddrType: NestedWitnessPubKey,
			InternalAddrType: WitnessPubKey,
		},
		KeyScopeBIP0084: {
			ExternalAddrType: WitnessPubKey,
			InternalAddrType: WitnessPubKey,
		},
		KeyScopeBIP0044: {
			InternalAddrType: PubKeyHash,
			ExternalAddrType: PubKeyHash,
		},
	}

// AddressType represents the various address types waddrmgr is currently able
// to generate, and maintain.
//
// NOTE: These MUST be stable as they're used for scope address schema
// recognition within the database.
type AddressType uint8

const (
	// PubKeyHash is a regular p2pkh address.
	PubKeyHash AddressType = iota

	// Script reprints a raw script address.
	Script

	// RawPubKey is just raw public key to be used within scripts, This
	// type indicates that a scoped manager with this address type
	// shouldn't be consulted during historical rescans.
	RawPubKey

	// NestedWitnessPubKey represents a p2wkh output nested within a p2sh
	// output. Using this address type, the wallet can receive funds from
	// other wallet's which don't yet recognize the new segwit standard
	// output types. Receiving funds to this address maintains the
	// scalability, and malleability fixes due to segwit in a backwards
	// compatible manner.
	NestedWitnessPubKey

	// WitnessPubKey represents a p2wkh (pay-to-witness-key-hash) address
	// type.
	WitnessPubKey
)

// ManagedAddress is an interface that provides acces to information regarding
// an address managed by an address manager. Concrete implementations of this
// type may provide further fields to provide information specific to that type
// of address.
type ManagedAddress interface {
	// Account returns the account the address is associated with.
	Account() uint32

	// Address returns a btcutil.Address for the backing address.
	Address() btcutil.Address

	// AddrHash returns the key or script hash related to the address
	AddrHash() []byte

	// Imported returns true if the backing address was imported instead
	// of being part of an address chain.
	Imported() bool

	// Internal returns true if the backing address was created for internal
	// use such as a change output of a transaction.
	Internal() bool

	// Compressed returns true if the backing address is compressed.
	Compressed() bool

	// Used returns true if the backing address has been used in a transaction.
	Used(ns walletdb.ReadBucket) bool

	// AddrType returns the address type of the managed address. This can
	// be used to quickly discern the address type without further
	// processing
	AddrType() AddressType
}

// ManagedPubKeyAddress extends ManagedAddress and additionally provides the
// public and private keys for pubkey-based addresses.
type ManagedPubKeyAddress interface {
	ManagedAddress

	// PubKey returns the public key associated with the address.
	PubKey() *btcec.PublicKey

	// ExportPubKey returns the public key associated with the address
	// serialized as a hex encoded string.
	ExportPubKey() string

	// PrivKey returns the private key for the address.  It can fail if the
	// address manager is watching-only or locked, or the address does not
	// have any keys.
	PrivKey() (*btcec.PrivateKey, error)

	// ExportPrivKey returns the private key associated with the address
	// serialized as Wallet Import Format (WIF).
	ExportPrivKey() (*btcutil.WIF, error)

	// DerivationInfo contains the information required to derive the key
	// that backs the address via traditional methods from the HD root. For
	// imported keys, the first value will be set to false to indicate that
	// we don't know exactly how the key was derived.
	DerivationInfo() (KeyScope, DerivationPath, bool)
}

// ManagedScriptAddress extends ManagedAddress and represents a pay-to-script-hash
// style of bitcoin addresses.  It additionally provides information about the
// script.
type ManagedScriptAddress interface {
	ManagedAddress

	// Script returns the script associated with the address.
	Script() ([]byte, error)
}

// Manager represents a concurrency safe crypto currency address manager and
// key store.
type Manager struct {
	mtx sync.RWMutex

	// scopedManager is a mapping of scope of scoped manager, the manager
	// itself loaded into memory.
	scopedManagers map[KeyScope]*ScopedKeyManager

	externalAddrSchemas map[AddressType][]KeyScope
	internalAddrSchemas map[AddressType][]KeyScope

	syncState    syncState
	watchingOnly bool
	birthday     time.Time
	locked       bool
	closed       bool
	chainParams  *chaincfg.Params

	// masterKeyPub is the secret key used to secure the cryptoKeyPub key
	// and masterKeyPriv is the secret key used to secure the cryptoKeyPriv
	// key.  This approach is used because it makes changing the passwords
	// much simpler as it then becomes just changing these keys.  It also
	// provides future flexibility.
	//
	// NOTE: This is not the same thing as BIP0032 master node extended
	// key.
	//
	// The underlying master private key will be zeroed when the address
	// manager is locked.
	masterKeyPub  *snacl.SecretKey
	masterKeyPriv *snacl.SecretKey

	// cryptoKeyPub is the key used to encrypt public extended keys and
	// addresses.
	cryptoKeyPub EncryptorDecryptor

	// cryptoKeyPriv is the key used to encrypt private data such as the
	// master hierarchical deterministic extended key.
	//
	// This key will be zeroed when the address manager is locked.
	cryptoKeyPrivEncrypted []byte
	cryptoKeyPriv          EncryptorDecryptor

	// cryptoKeyScript is the key used to encrypt script data.
	//
	// This key will be zeroed when the address manager is locked.
	cryptoKeyScriptEncrypted []byte
	cryptoKeyScript          EncryptorDecryptor

	// privPassphraseSalt and hashedPrivPassphrase allow for the secure
	// detection of a correct passphrase on manager unlock when the
	// manager is already unlocked.  The hash is zeroed each lock.
	privPassphraseSalt   [saltSize]byte
	hashedPrivPassphrase [sha512.Size]byte
}