From 86d4080061e57abefa892dc7eba7b95894063192 Mon Sep 17 00:00:00 2001
From: Dastan-glitch <Dastan.ManDan@gmail.com>
Date: Tue, 13 Jun 2023 04:03:13 +0300
Subject: [PATCH] bin/darkirc: resetting root every 24hrs at 00:00AM UTC

---
 bin/darkirc/src/main.rs  | 34 +++++++++++++++++++++++++++++++---
 src/event_graph/model.rs | 25 ++++++++++++++++++++++++-
 2 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/bin/darkirc/src/main.rs b/bin/darkirc/src/main.rs
index 39e3b0171..6f3acb306 100644
--- a/bin/darkirc/src/main.rs
+++ b/bin/darkirc/src/main.rs
@@ -21,6 +21,8 @@ use async_std::{
     sync::{Arc, Mutex},
     task,
 };
+
+use chrono::{Duration, Utc};
 use irc::ClientSubMsg;
 use log::{debug, error, info, warn};
 use rand::rngs::OsRng;
@@ -32,14 +34,14 @@ use darkfi::{
     async_daemonize,
     event_graph::{
         events_queue::EventsQueue,
-        model::Model,
+        model::{Model, ModelPtr},
         protocol_event::{ProtocolEvent, Seen},
         view::View,
     },
     net,
     rpc::server::listen_and_serve,
     system::{Subscriber, SubscriberPtr},
-    util::{file::save_json_file, path::expand_path},
+    util::{async_util::sleep, file::save_json_file, path::expand_path, time::Timestamp},
     Result,
 };
 
@@ -94,6 +96,7 @@ async fn realmain(settings: Args, executor: Arc<smol::Executor<'_>>) -> Result<(
     let model = Arc::new(Mutex::new(Model::new(events_queue.clone())));
     let view = Arc::new(Mutex::new(View::new(events_queue)));
     let model_clone = model.clone();
+    let model_clone2 = model.clone();
 
     ////////////////////
     // P2p setup
@@ -155,7 +158,10 @@ async fn realmain(settings: Args, executor: Arc<smol::Executor<'_>>) -> Result<(
 
     // Start the irc server and detach it
     let executor_cloned = executor.clone();
-    executor_cloned.spawn(async move { irc_server.start(executor.clone()).await }).detach();
+    executor.spawn(async move { irc_server.start(executor_cloned).await }).detach();
+
+    // Reset root task
+    executor.spawn(async move { reset_root(model_clone2).await }).detach();
 
     ////////////////////
     // Wait for termination signal
@@ -200,3 +206,25 @@ async fn handle_signals(
     }
     Ok(())
 }
+
+async fn reset_root(model: ModelPtr<PrivMsgEvent>) {
+    loop {
+        let now = Utc::now();
+
+        // clocks are valid, safe to unwrap
+        let next_midnight = (now + Duration::days(1)).date_naive().and_hms_opt(0, 0, 0).unwrap();
+
+        let duration = next_midnight.signed_duration_since(now.naive_utc()).to_std().unwrap();
+
+        // make sure the root is the same as everyone else's at
+        // startup by passing today's date 00:00 AM UTC as
+        // timestamp to root_event
+        let now_datetime = now.date_naive().and_hms_opt(0, 0, 0).unwrap();
+        let timestamp = now_datetime.timestamp() as u64;
+
+        model.lock().await.reset_root(Timestamp(timestamp));
+
+        sleep(duration.as_secs()).await;
+        info!("Resetting root");
+    }
+}
diff --git a/src/event_graph/model.rs b/src/event_graph/model.rs
index edbbdd409..5bbb786f1 100644
--- a/src/event_graph/model.rs
+++ b/src/event_graph/model.rs
@@ -21,7 +21,7 @@ use std::{cmp::Ordering, collections::HashMap, fmt::Debug};
 use async_std::sync::{Arc, Mutex};
 use blake3;
 use darkfi_serial::{serialize, Decodable, Encodable, SerialDecodable, SerialEncodable};
-use log::error;
+use log::{error, info};
 
 use crate::{event_graph::events_queue::EventsQueuePtr, util::time::Timestamp};
 
@@ -90,6 +90,29 @@ where
         Self { current_root: root_node_id, orphans: HashMap::new(), event_map, events_queue }
     }
 
+    pub fn reset_root(&mut self, timestamp: Timestamp) {
+        let root_node = EventNode {
+            parent: None,
+            event: Event {
+                previous_event_hash: blake3::hash(b""), // This is a blake3 hash of NULL
+                action: T::new(),
+                timestamp,
+            },
+            children: Vec::new(),
+        };
+
+        let root_node_id = root_node.event.hash();
+
+        let mut event_map = HashMap::new();
+        event_map.insert(root_node_id, root_node);
+
+        self.current_root = root_node_id;
+        self.orphans = HashMap::new();
+        self.event_map = event_map;
+
+        info!("reset current root to: {:?}", self.current_root);
+    }
+
     pub fn get_head_hash(&self) -> EventId {
         self.find_head()
     }