refactor: Move wallet methods out of chain.h and node.h

Add WalletClient interface so node interface is cleaner and don't need
wallet-specific methods.

The new NodeContext::wallet_client pointer will also be needed to eliminate
global wallet variables like ::vpwallets, because createWallet(), loadWallet(),
getWallets(), etc methods called by the GUI need a way to get a reference to
the list of open wallets if it is no longer a global variable.

Also tweaks splash screen registration for load wallet events to be delayed
until after wallet client is created.

1 files changed, 35 insertions, 0 deletions

diff --git a/src/interfaces/wallet.h b/src/interfaces/wallet.h
index 3cdadbc72e..186f5d81a5 100644
--- a/src/interfaces/wallet.h
+++ b/src/interfaces/wallet.h
@@ -6,6 +6,7 @@
 #define BITCOIN_INTERFACES_WALLET_H
 
 #include <amount.h>                    // For CAmount
+#include <interfaces/chain.h>          // For ChainClient
 #include <pubkey.h>                    // For CKeyID and CScriptID (definitions needed in CTxDestination instantiation)
 #include <script/standard.h>           // For CTxDestination
 #include <support/allocators/secure.h> // For SecureString
@@ -28,9 +29,11 @@ class CWallet;
 enum class FeeReason;
 enum class OutputType;
 enum class TransactionError;
+enum class WalletCreationStatus;
 enum isminetype : unsigned int;
 struct CRecipient;
 struct PartiallySignedTransaction;
+struct WalletContext;
 struct bilingual_str;
 typedef uint8_t isminefilter;
 
@@ -301,6 +304,34 @@ public:
     virtual CWallet* wallet() { return nullptr; }
 };
 
+//! Wallet chain client that in addition to having chain client methods for
+//! starting up, shutting down, and registering RPCs, also has additional
+//! methods (called by the GUI) to load and create wallets.
+class WalletClient : public ChainClient
+{
+public:
+    //! Create new wallet.
+    virtual std::unique_ptr<Wallet> createWallet(const std::string& name, const SecureString& passphrase, uint64_t wallet_creation_flags, WalletCreationStatus& status, bilingual_str& error, std::vector<bilingual_str>& warnings) = 0;
+
+   //! Load existing wallet.
+   virtual std::unique_ptr<Wallet> loadWallet(const std::string& name, bilingual_str& error, std::vector<bilingual_str>& warnings) = 0;
+
+   //! Return default wallet directory.
+   virtual std::string getWalletDir() = 0;
+
+   //! Return available wallets in wallet directory.
+   virtual std::vector<std::string> listWalletDir() = 0;
+
+   //! Return interfaces for accessing wallets (if any).
+   virtual std::vector<std::unique_ptr<Wallet>> getWallets() = 0;
+
+   //! Register handler for load wallet messages. This callback is triggered by
+   //! createWallet and loadWallet above, and also triggered when wallets are
+   //! loaded at startup or by RPC.
+   using LoadWalletFn = std::function<void(std::unique_ptr<Wallet> wallet)>;
+   virtual std::unique_ptr<Handler> handleLoadWallet(LoadWalletFn fn) = 0;
+};
+
 //! Information about one wallet address.
 struct WalletAddress
 {
@@ -379,6 +410,10 @@ struct WalletTxOut
 //! dummywallet.cpp and throws if the wallet component is not compiled.
 std::unique_ptr<Wallet> MakeWallet(const std::shared_ptr<CWallet>& wallet);
 
+//! Return implementation of ChainClient interface for a wallet client. This
+//! function will be undefined in builds where ENABLE_WALLET is false.
+std::unique_ptr<WalletClient> MakeWalletClient(Chain& chain, ArgsManager& args, std::vector<std::string> wallet_filenames);
+
 } // namespace interfaces
 
 #endif // BITCOIN_INTERFACES_WALLET_H