From e637e843e7e0ab5a60e87f04bbf78d1e64989342 Mon Sep 17 00:00:00 2001
From: adi2011 <aditya.sharma.met19@itbhu.ac.in>
Date: Thu, 2 Feb 2023 20:31:25 +1030
Subject: [PATCH] Plugins/chanbackup: Add RPC for recovering from the latestscb
 received from peers.

---
 plugins/chanbackup.c | 72 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 71 insertions(+), 1 deletion(-)

diff --git a/plugins/chanbackup.c b/plugins/chanbackup.c
index bd861a2b0..ca480433e 100644
--- a/plugins/chanbackup.c
+++ b/plugins/chanbackup.c
@@ -258,7 +258,7 @@ static struct command_result *json_emergencyrecover(struct command *cmd,
 
 	if (version != VERSION) {
 		plugin_err(cmd->plugin,
-                           "Incompatible version, Contact the admin!");
+                           "Incompatible SCB file version on disk, contact the admin!");
 	}
 
 	req = jsonrpc_request_start(cmd->plugin, cmd, "recoverchannel",
@@ -665,6 +665,67 @@ static struct command_result *handle_your_peer_storage(struct command *cmd,
         }
 }
 
+static struct command_result *after_latestscb(struct command *cmd,
+					        const u8 *res,
+					        void *cb_arg UNUSED)
+{
+        u64 version;
+	u32 timestamp;
+	struct scb_chan **scb;
+        struct json_stream *response;
+        struct out_req *req;
+
+        if (tal_bytelen(res) == 0) {
+        	response = jsonrpc_stream_success(cmd);
+
+		json_add_string(response, "result",
+				"No backup received from peers");
+		return command_finished(cmd, response);
+        }
+
+	if (!fromwire_static_chan_backup(cmd,
+                                         res,
+                                         &version,
+                                         &timestamp,
+                                         &scb)) {
+		plugin_err(cmd->plugin, "Corrupted SCB on disk!");
+	}
+
+	if (version != VERSION) {
+		plugin_err(cmd->plugin,
+                           "Incompatible version, Contact the admin!");
+	}
+
+        req = jsonrpc_request_start(cmd->plugin, cmd, "recoverchannel",
+				after_recover_rpc,
+				&forward_error, NULL);
+
+	json_array_start(req->js, "scb");
+	for (size_t i=0; i<tal_count(scb); i++) {
+		u8 *scb_hex = tal_arr(cmd, u8, 0);
+		towire_scb_chan(&scb_hex,scb[i]);
+		json_add_hex(req->js, NULL, scb_hex, tal_bytelen(scb_hex));
+	}
+	json_array_end(req->js);
+
+	return send_outreq(cmd->plugin, req);
+
+}
+
+static struct command_result *json_restorefrompeer(struct command *cmd,
+				      const char *buf,
+                                      const jsmntok_t *params)
+{
+	if (!param(cmd, buf, params, NULL))
+		return command_param_failed();
+
+	return jsonrpc_get_datastore_binary(cmd->plugin,
+				     	    cmd,
+				     	    "chanbackup/latestscb",
+				     	    after_latestscb,
+				     	    NULL);
+}
+
 static const char *init(struct plugin *p,
 			const char *buf UNUSED,
 			const jsmntok_t *config UNUSED)
@@ -719,6 +780,15 @@ static const struct plugin_command commands[] = { {
 		"returns stub channel-id's on completion",
 		json_emergencyrecover,
 	},
+        {
+                "restorefrompeer",
+                "recovery",
+                "Checks if i have got a backup from a peer, and if so, will stub "
+		"those channels in the database and if is successful, will return "
+		"list of channels that have been successfully stubbed",
+                "return channel-id's on completion",
+                json_restorefrompeer,
+        },
 };
 
 int main(int argc, char *argv[])