From adf4970fa4e6ea4ef6ab22fb5612c3e2c6aaf268 Mon Sep 17 00:00:00 2001
From: Josh Rickmar <jrick@conformal.com>
Date: Wed, 23 Oct 2013 18:23:20 -0400
Subject: [PATCH] Keep a pool of unmined transactions, and resend if unmined.

---
 cmdmgr.go   |  6 ++++++
 createtx.go | 12 ++++++++++++
 sockets.go  | 41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 59 insertions(+)

diff --git a/cmdmgr.go b/cmdmgr.go
index 65541d1..fe16539 100644
--- a/cmdmgr.go
+++ b/cmdmgr.go
@@ -574,6 +574,12 @@ func SendMany(reply chan []byte, msg *btcjson.Message) {
 			w.UtxoStore.Unlock()
 		}
 
+		// Add hex string of raw tx to sent tx pool.  If future blocks
+		// do not contain a tx, a resend is attempted.
+		UnminedTxs.Lock()
+		UnminedTxs.m[result.(string)] = hex.EncodeToString(rawtx)
+		UnminedTxs.Unlock()
+
 		ReplySuccess(reply, msg.Id, result)
 
 		// TODO(jrick): If message succeeded in being sent, save the
diff --git a/createtx.go b/createtx.go
index 6d143ea..a6e444a 100644
--- a/createtx.go
+++ b/createtx.go
@@ -44,6 +44,18 @@ var TxFee struct {
 	i int64
 }
 
+// UnminedTXs holds a map of transaction IDs as keys mapping to a
+// hex string of a raw transaction.  If sending a raw transaction
+// succeeds, the tx is added to this map and checked again after each
+// new block.  If the new block contains a tx, it is removed from
+// this map.  Otherwise, btcwallet will resend the tx to btcd.
+var UnminedTxs = struct {
+	sync.Mutex
+	m map[string]string
+}{
+	m: make(map[string]string),
+}
+
 // ByAmount defines the methods needed to satisify sort.Interface to
 // sort a slice of Utxos by their amount.
 type ByAmount []*tx.Utxo
diff --git a/sockets.go b/sockets.go
index b8c1316..3f8c4c0 100644
--- a/sockets.go
+++ b/sockets.go
@@ -341,8 +341,23 @@ func NtfnBlockConnected(r interface{}) {
 	heightf, ok := result["height"].(float64)
 	if !ok {
 		log.Error("blockconnected notification: invalid height")
+		return
 	}
 	height := int64(heightf)
+	iminedTxs, ok := result["minedtxs"].([]interface{})
+	if !ok {
+		log.Error("blockconnected notification: invalid mined tx array")
+		return
+	}
+	minedTxs := make([]string, len(iminedTxs))
+	for i, iminedTx := range iminedTxs {
+		minedTx, ok := iminedTx.(string)
+		if !ok {
+			log.Error("blockconnected notification: mined tx is not a string")
+			continue
+		}
+		minedTxs[i] = minedTx
+	}
 
 	curHeight.Lock()
 	curHeight.h = height
@@ -370,6 +385,32 @@ func NtfnBlockConnected(r interface{}) {
 		NotifyWalletBalanceUnconfirmed(frontendNotificationMaster, w.name, unconfirmed)
 	}
 	wallets.RUnlock()
+
+	// Remove all mined transactions from pool.
+	UnminedTxs.Lock()
+	for _, txid := range minedTxs {
+		delete(UnminedTxs.m, txid)
+	}
+
+	// Resend any remaining transactions still left in pool.  These are
+	// transactions that have not yet been mined into a block.
+	for _, hextx := range UnminedTxs.m {
+		n := <-NewJSONID
+		var id interface{} = fmt.Sprintf("btcwallet(%v)", n)
+		m, err := btcjson.CreateMessageWithId("sendrawtransaction", id, hextx)
+		if err != nil {
+			log.Errorf("cannot create resend request: %v", err)
+			continue
+		}
+		replyHandlers.Lock()
+		replyHandlers.m[n] = func(result interface{}, err *btcjson.Error) bool {
+			// Do nothing, just remove the handler.
+			return true
+		}
+		replyHandlers.Unlock()
+		btcdMsgs <- m
+	}
+	UnminedTxs.Unlock()
 }
 
 // NtfnBlockDisconnected handles btcd notifications resulting from