Fix system order ambiguities (#74)

* start fixing stuff where systems run in the wrong order

* fix ordering ambiguity

* add debugging guide

* some fixes

* fix panic for swarms

* fix some warnings

7 files changed, 52 insertions, 104 deletions

diff --git a/azalea-client/Cargo.toml b/azalea-client/Cargo.toml
index 9fae2fbe..6bb31069 100644
--- a/azalea-client/Cargo.toml
+++ b/azalea-client/Cargo.toml
@@ -11,29 +11,27 @@ version = "0.6.0"
 [dependencies]
 anyhow = "1.0.59"
 async-trait = "0.1.58"
-azalea-auth = {path = "../azalea-auth", version = "0.6.0"}
-azalea-block = {path = "../azalea-block", version = "0.6.0"}
-azalea-chat = {path = "../azalea-chat", version = "0.6.0"}
-azalea-core = {path = "../azalea-core", version = "0.6.0"}
-azalea-crypto = {path = "../azalea-crypto", version = "0.6.0"}
-azalea-ecs = {path = "../azalea-ecs", version = "0.6.0"}
-azalea-physics = {path = "../azalea-physics", version = "0.6.0"}
-azalea-protocol = {path = "../azalea-protocol", version = "0.6.0"}
-azalea-registry = {path = "../azalea-registry", version = "0.6.0"}
-azalea-world = {path = "../azalea-world", version = "0.6.0"}
+azalea-auth = { path = "../azalea-auth", version = "0.6.0" }
+azalea-block = { path = "../azalea-block", version = "0.6.0" }
+azalea-chat = { path = "../azalea-chat", version = "0.6.0" }
+azalea-core = { path = "../azalea-core", version = "0.6.0" }
+azalea-crypto = { path = "../azalea-crypto", version = "0.6.0" }
+azalea-ecs = { path = "../azalea-ecs", version = "0.6.0" }
+azalea-physics = { path = "../azalea-physics", version = "0.6.0" }
+azalea-protocol = { path = "../azalea-protocol", version = "0.6.0" }
+azalea-registry = { path = "../azalea-registry", version = "0.6.0" }
+azalea-world = { path = "../azalea-world", version = "0.6.0" }
+bevy_log = "0.9.1"
 bevy_tasks = "0.9.1"
 bevy_time = "0.9.1"
-derive_more = {version = "0.99.17", features = ["deref", "deref_mut"]}
+derive_more = { version = "0.99.17", features = ["deref", "deref_mut"] }
 futures = "0.3.25"
 log = "0.4.17"
 nohash-hasher = "0.2.0"
 once_cell = "1.16.0"
-parking_lot = {version = "^0.12.1", features = ["deadlock_detection"]}
+parking_lot = { version = "^0.12.1", features = ["deadlock_detection"] }
 regex = "1.7.0"
 thiserror = "^1.0.34"
-tokio = {version = "^1.24.2", features = ["sync"]}
+tokio = { version = "^1.24.2", features = ["sync"] }
 typemap_rev = "0.3.0"
 uuid = "^1.1.2"
-
-[dev-dependencies]
-env_logger = "0.9.1"
diff --git a/azalea-client/examples/echo.rs b/azalea-client/examples/echo.rs
deleted file mode 100644
index f37cd904..00000000
--- a/azalea-client/examples/echo.rs
+++ /dev/null
@@ -1,49 +0,0 @@
-//! A simple bot that repeats chat messages sent by other players.
-
-use azalea_client::{Account, Client, Event};
-
-#[tokio::main]
-async fn main() {
-    env_logger::init();
-    // deadlock detection, you can safely delete this block if you're not trying to
-    // debug deadlocks in azalea
-    {
-        use parking_lot::deadlock;
-        use std::thread;
-        use std::time::Duration;
-        thread::spawn(move || loop {
-            thread::sleep(Duration::from_secs(10));
-            let deadlocks = deadlock::check_deadlock();
-            if deadlocks.is_empty() {
-                continue;
-            }
-            println!("{} deadlocks detected", deadlocks.len());
-            for (i, threads) in deadlocks.iter().enumerate() {
-                println!("Deadlock #{i}");
-                for t in threads {
-                    println!("Thread Id {:#?}", t.thread_id());
-                    println!("{:#?}", t.backtrace());
-                }
-            }
-        });
-    }
-
-    let account = Account::offline("bot");
-    // or let account = Account::microsoft("email").await;
-
-    let (client, mut rx) = Client::join(&account, "localhost").await.unwrap();
-
-    while let Some(event) = rx.recv().await {
-        match &event {
-            Event::Chat(m) => {
-                if let (Some(sender), content) = m.split_sender_and_content() {
-                    if sender == client.profile.name {
-                        continue; // ignore our own messages
-                    }
-                    client.chat(&content);
-                };
-            }
-            _ => {}
-        }
-    }
-}
diff --git a/azalea-client/src/chat.rs b/azalea-client/src/chat.rs
index ac119f24..202cf47c 100755
--- a/azalea-client/src/chat.rs
+++ b/azalea-client/src/chat.rs
@@ -19,7 +19,10 @@ use std::{
 };
 use uuid::Uuid;
 
-use crate::{client::Client, local_player::SendPacketEvent};
+use crate::{
+    client::Client,
+    local_player::{handle_send_packet_event, SendPacketEvent},
+};
 
 /// A chat packet, either a system message or a chat message.
 #[derive(Debug, Clone, PartialEq)]
@@ -155,15 +158,12 @@ impl Plugin for ChatPlugin {
         app.add_event::<SendChatEvent>()
             .add_event::<SendChatKindEvent>()
             .add_event::<ChatReceivedEvent>()
-            .add_system(
-                handle_send_chat_event
-                    .label("handle_send_chat_event")
-                    .after("packet"),
-            )
+            .add_system(handle_send_chat_event.label("handle_send_chat_event"))
             .add_system(
                 handle_send_chat_kind_event
                     .label("handle_send_chat_kind_event")
-                    .after("handle_send_chat_event"),
+                    .after(handle_send_chat_event)
+                    .after(handle_send_packet_event),
             );
     }
 }
diff --git a/azalea-client/src/client.rs b/azalea-client/src/client.rs
index 69a50c33..661858db 100644
--- a/azalea-client/src/client.rs
+++ b/azalea-client/src/client.rs
@@ -20,7 +20,7 @@ use azalea_ecs::{
     bundle::Bundle,
     component::Component,
     entity::Entity,
-    schedule::{IntoSystemDescriptor, Schedule, Stage, SystemSet},
+    schedule::{IntoSystemDescriptor, ReportExecutionOrderAmbiguities, Schedule, Stage, SystemSet},
     AppTickExt,
 };
 use azalea_ecs::{ecs::Ecs, TickPlugin};
@@ -49,6 +49,7 @@ use azalea_world::{
     entity::{EntityPlugin, Local, WorldName},
     PartialWorld, World, WorldContainer,
 };
+use bevy_log::LogPlugin;
 use log::{debug, error};
 use parking_lot::{Mutex, RwLock};
 use std::{collections::HashMap, fmt::Debug, io, net::SocketAddr, sync::Arc};
@@ -497,36 +498,31 @@ impl Plugin for AzaleaPlugin {
 
         app.add_tick_system_set(
             SystemSet::new()
-                .with_system(send_position)
-                .with_system(update_in_loaded_chunk)
+                .with_system(send_position.after("ai_step"))
+                .with_system(update_in_loaded_chunk.before(send_position).after("travel"))
                 .with_system(
                     local_player_ai_step
-                        .before("ai_step")
-                        .after("sprint_listener"),
+                        .before(azalea_physics::ai_step)
+                        .label("ai_step"),
                 ),
         );
 
         // fire the Death event when the player dies.
-        app.add_system(death_event.after("tick").after("packet"));
+        app.add_system(death_event);
 
         // walk and sprint event listeners
-        app.add_system(walk_listener.label("walk_listener").before("travel"))
+        app.add_system(walk_listener.label("walk_listener"))
             .add_system(
                 sprint_listener
                     .label("sprint_listener")
-                    .before("travel")
                     .before("walk_listener"),
             );
 
         // add GameProfileComponent when we get an AddPlayerEvent
-        app.add_system(
-            retroactively_add_game_profile_component
-                .after("tick")
-                .after("packet"),
-        );
+        app.add_system(retroactively_add_game_profile_component.after("update_indexes"));
 
         app.add_event::<SendPacketEvent>()
-            .add_system(handle_send_packet_event.after("tick").after("packet"));
+            .add_system(handle_send_packet_event);
 
         app.init_resource::<WorldContainer>();
     }
@@ -547,6 +543,9 @@ pub fn init_ecs_app() -> App {
     // you might be able to just drop the lock or put it in its own scope to fix
 
     let mut app = App::new();
+
+    app.insert_resource(ReportExecutionOrderAmbiguities);
+
     app.add_plugins(DefaultPlugins);
     app
 }
@@ -609,9 +608,10 @@ pub struct DefaultPlugins;
 impl PluginGroup for DefaultPlugins {
     fn build(self) -> PluginGroupBuilder {
         PluginGroupBuilder::start::<Self>()
+            .add(LogPlugin::default())
             .add(TickPlugin::default())
-            .add(AzaleaPlugin)
             .add(PacketHandlerPlugin)
+            .add(AzaleaPlugin)
             .add(EntityPlugin)
             .add(PhysicsPlugin)
             .add(EventPlugin)
diff --git a/azalea-client/src/disconnect.rs b/azalea-client/src/disconnect.rs
index 83870e69..9fd57e57 100644
--- a/azalea-client/src/disconnect.rs
+++ b/azalea-client/src/disconnect.rs
@@ -12,7 +12,7 @@ use azalea_ecs::{
 };
 use derive_more::Deref;
 
-use crate::{client::JoinedClientBundle, LocalPlayer};
+use crate::{client::JoinedClientBundle, movement::send_position, LocalPlayer};
 
 pub struct DisconnectPlugin;
 impl Plugin for DisconnectPlugin {
@@ -20,7 +20,9 @@ impl Plugin for DisconnectPlugin {
         app.add_event::<DisconnectEvent>()
             .add_system_to_stage(CoreStage::PostUpdate, handle_disconnect)
             .add_tick_system(
-                update_read_packets_task_running_component.before(disconnect_on_read_packets_ended),
+                update_read_packets_task_running_component
+                    .before(disconnect_on_read_packets_ended)
+                    .before(send_position),
             )
             .add_tick_system(disconnect_on_read_packets_ended);
     }
diff --git a/azalea-client/src/packet_handling.rs b/azalea-client/src/packet_handling.rs
index d5cce3a8..a4d638a4 100644
--- a/azalea-client/src/packet_handling.rs
+++ b/azalea-client/src/packet_handling.rs
@@ -2,13 +2,12 @@ use std::{collections::HashSet, io::Cursor, sync::Arc};
 
 use azalea_core::{ChunkPos, ResourceLocation, Vec3};
 use azalea_ecs::{
-    app::{App, Plugin},
+    app::{App, CoreStage, Plugin},
     component::Component,
     ecs::Ecs,
     entity::Entity,
     event::EventWriter,
     query::Changed,
-    schedule::{IntoSystemDescriptor, SystemSet},
     system::{Commands, Query, ResMut, SystemState},
 };
 use azalea_protocol::{
@@ -47,15 +46,13 @@ pub struct PacketHandlerPlugin;
 
 impl Plugin for PacketHandlerPlugin {
     fn build(&self, app: &mut App) {
-        app.add_system_set(
-            SystemSet::new().with_system(handle_packets.label("packet").before("tick")),
-        )
-        .add_event::<AddPlayerEvent>()
-        .add_event::<RemovePlayerEvent>()
-        .add_event::<UpdatePlayerEvent>()
-        .add_event::<ChatReceivedEvent>()
-        .add_event::<DeathEvent>()
-        .add_event::<KeepAliveEvent>();
+        app.add_system_to_stage(CoreStage::PreUpdate, handle_packets)
+            .add_event::<AddPlayerEvent>()
+            .add_event::<RemovePlayerEvent>()
+            .add_event::<UpdatePlayerEvent>()
+            .add_event::<ChatReceivedEvent>()
+            .add_event::<DeathEvent>()
+            .add_event::<KeepAliveEvent>();
     }
 }
 
@@ -110,7 +107,7 @@ pub struct PacketReceiver {
     pub run_schedule_sender: mpsc::UnboundedSender<()>,
 }
 
-fn handle_packets(ecs: &mut Ecs) {
+pub fn handle_packets(ecs: &mut Ecs) {
     let mut events_owned = Vec::new();
 
     {
diff --git a/azalea-client/src/player.rs b/azalea-client/src/player.rs
index 8bccedc8..3680e2d0 100755
--- a/azalea-client/src/player.rs
+++ b/azalea-client/src/player.rs
@@ -36,9 +36,9 @@ pub fn retroactively_add_game_profile_component(
 ) {
     for event in events.iter() {
         if let Some(entity) = entity_infos.get_entity_by_uuid(&event.info.uuid) {
-            if let Some(mut entity_commands) = commands.get_entity(entity) {
-                entity_commands.insert(GameProfileComponent(event.info.profile.clone()));
-            }
+            commands
+                .entity(entity)
+                .insert(GameProfileComponent(event.info.profile.clone()));
         }
     }
 }