From 2d04d31894586d69524d43b78e605239499032b2 Mon Sep 17 00:00:00 2001
From: Roy Lee <roylee17@gmail.com>
Date: Fri, 19 Aug 2022 11:57:29 -0700
Subject: [PATCH] rpc: implement rescanblockchain rpcclient

---
 btcjson/walletsvrcmds.go    | 19 +++++++++++++++++++
 btcjson/walletsvrresults.go |  6 ++++++
 rpcclient/wallet.go         | 38 +++++++++++++++++++++++++++++++++++++
 rpcserver.go                |  1 +
 4 files changed, 64 insertions(+)

diff --git a/btcjson/walletsvrcmds.go b/btcjson/walletsvrcmds.go
index cf77877a..bc1515f9 100644
--- a/btcjson/walletsvrcmds.go
+++ b/btcjson/walletsvrcmds.go
@@ -960,6 +960,24 @@ func NewImportMultiCmd(requests []ImportMultiRequest, options *ImportMultiOption
 	}
 }
 
+// RescanBlockchainCmd defines the RescanBlockchain JSON-RPC command.
+type RescanBlockchainCmd struct {
+	StartHeight *int64 `jsonrpcdefault:"0"`
+	StopHeight  *int64 `jsonrpcdefault:"0"`
+}
+
+// NewRescanBlockchainCmd returns a new instance which can be used to issue
+// an RescanBlockchain JSON-RPC command.
+//
+// The parameters which are pointers indicate they are optional. Passing nil
+// for optional parameters will use the default value.
+func NewRescanBlockchainCmd(startHeight *int64, stopHeight *int64) *RescanBlockchainCmd {
+	return &RescanBlockchainCmd{
+		StartHeight: startHeight,
+		StopHeight:  stopHeight,
+	}
+}
+
 // PsbtInput represents an input to include in the PSBT created by the
 // WalletCreateFundedPsbtCmd command.
 type PsbtInput struct {
@@ -1081,6 +1099,7 @@ func init() {
 	MustRegisterCmd("listunspent", (*ListUnspentCmd)(nil), flags)
 	MustRegisterCmd("loadwallet", (*LoadWalletCmd)(nil), flags)
 	MustRegisterCmd("lockunspent", (*LockUnspentCmd)(nil), flags)
+	MustRegisterCmd("rescanblockchain", (*RescanBlockchainCmd)(nil), flags)
 	MustRegisterCmd("sendfrom", (*SendFromCmd)(nil), flags)
 	MustRegisterCmd("sendmany", (*SendManyCmd)(nil), flags)
 	MustRegisterCmd("sendtoaddress", (*SendToAddressCmd)(nil), flags)
diff --git a/btcjson/walletsvrresults.go b/btcjson/walletsvrresults.go
index 42402496..0c07ac1c 100644
--- a/btcjson/walletsvrresults.go
+++ b/btcjson/walletsvrresults.go
@@ -317,6 +317,12 @@ type ListUnspentResult struct {
 	IsStake       bool    `json:"isstake"`
 }
 
+// RescanBlockchainResult models the data returned from the rescanblockchain command.
+type RescanBlockchainResult struct {
+	StartHeight int64 `json:"start_height"`
+	StoptHeight int64 `json:"stop_height"`
+}
+
 // SignRawTransactionError models the data that contains script verification
 // errors from the signrawtransaction request.
 type SignRawTransactionError struct {
diff --git a/rpcclient/wallet.go b/rpcclient/wallet.go
index bc4dd917..54a5c56f 100644
--- a/rpcclient/wallet.go
+++ b/rpcclient/wallet.go
@@ -2027,6 +2027,44 @@ func (c *Client) ListReceivedByAddressIncludeEmpty(minConfirms int, includeEmpty
 		includeEmpty).Receive()
 }
 
+// FutureRescanBlockchainResult is a future promise to deliver the error result of a
+// RescanBlockchainAsync RPC invocation.
+type FutureRescanBlockchainResult chan *Response
+
+// Receive waits for the Response promised by the future and returns the result
+// of locking or unlocking the unspent output(s).
+func (r FutureRescanBlockchainResult) Receive() (*btcjson.RescanBlockchainResult, error) {
+	res, err := ReceiveFuture(r)
+	if err != nil {
+		return nil, err
+	}
+
+	// Unmarshal as an array of listreceivedbyaddress result objects.
+	var received btcjson.RescanBlockchainResult
+	err = json.Unmarshal(res, &received)
+	if err != nil {
+		return nil, err
+	}
+
+	return &received, nil
+}
+
+// RescanBlockchainAsync returns an instance of a type that can be used to get the
+// result of the RPC at some future time by invoking the Receive function on the
+// returned instance.
+//
+// See RescanBlockchain for the blocking version and more details.
+func (c *Client) RescanBlockchainAsync(startHeight *int64, stopHeight *int64) FutureRescanBlockchainResult {
+	cmd := btcjson.NewRescanBlockchainCmd(startHeight, stopHeight)
+	return c.SendCmd(cmd)
+}
+
+// RescanBlockchain rescans the local blockchain for wallet related
+// transactions from the startHeight to the the inclusive stopHeight.
+func (c *Client) RescanBlockchain(startHeight *int64, stopHeight *int64) (*btcjson.RescanBlockchainResult, error) {
+	return c.RescanBlockchainAsync(startHeight, stopHeight).Receive()
+}
+
 // ************************
 // Wallet Locking Functions
 // ************************
diff --git a/rpcserver.go b/rpcserver.go
index f02e347a..c9ca0eda 100644
--- a/rpcserver.go
+++ b/rpcserver.go
@@ -228,6 +228,7 @@ var rpcAskWallet = map[string]struct{}{
 	"listtransactions":       {},
 	"listunspent":            {},
 	"lockunspent":            {},
+	"rescanblockchain":       {},
 	"sendfrom":               {},
 	"sendmany":               {},
 	"sendtoaddress":          {},