feat(plugins): async plugin loading (#2327)

* work

* refactor(plugins): break down start plugin async function

* work

* loading messages

* nice ui

* floating panes and error handling

* cleanups and conflicting plugin/direction

* find exact pane when relayouting

* fix plugin pane titles

* kill loading tasks on exit

* refactor: move stuff around

* style(fmt): rustfmt

* various fixes and refactors

src/main.rs

@@ -32,6 +32,7 @@ fn main() {
         {
             let command_cli_action = CliAction::NewPane {
                 command,
+                plugin: None,
                 direction,
                 cwd,
                 floating,

src/tests/e2e/snapshots/zellij__tests__e2e__cases__bracketed_paste.snap

@@ -1,6 +1,6 @@
 ---
 source: src/tests/e2e/cases.rs
-assertion_line: 1671
+assertion_line: 1640
 expression: last_snapshot
 ---
  Zellij (e2e-test)  Tab #1                                                                                            
@@ -25,5 +25,5 @@ expression: last_snapshot
 │                                                                                                                      │
 │                                                                                                                      │
 └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
- Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT           
+ Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT  BASE   
  Tip: Alt + <n> => new pane. Alt + <←↓↑→> or Alt + <hjkl> => navigate. Alt + <+|-> => resize pane.                      

src/tests/e2e/snapshots/zellij__tests__e2e__cases__lock_mode.snap

@@ -1,6 +1,6 @@
 ---
 source: src/tests/e2e/cases.rs
-assertion_line: 803
+assertion_line: 804
 expression: last_snapshot
 ---
  Zellij (e2e-test)  Tab #1                                                                                            
@@ -25,5 +25,5 @@ expression: last_snapshot
 │                                                                                                                      │
 │                                                                                                                      │
 └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
- Ctrl + <g> LOCK  <> PANE  <> TAB  <> RESIZE  <> MOVE  <> SEARCH  <> SESSION  <> QUIT                  
+ Ctrl + <g> LOCK  <> PANE  <> TAB  <> RESIZE  <> MOVE  <> SEARCH  <> SESSION  <> QUIT          BASE  
  -- INTERFACE LOCKED --                                                                                                 

src/tests/e2e/snapshots/zellij__tests__e2e__cases__starts_with_one_terminal.snap

@@ -1,6 +1,6 @@
 ---
 source: src/tests/e2e/cases.rs
-assertion_line: 107
+assertion_line: 108
 expression: last_snapshot
 ---
  Zellij (e2e-test)  Tab #1                                                                                            
@@ -25,5 +25,5 @@ expression: last_snapshot
 │                                                                                                                      │
 │                                                                                                                      │
 └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
- Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT           
+ Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT  BASE   
  Tip: Alt + <n> => new pane. Alt + <←↓↑→> or Alt + <hjkl> => navigate. Alt + <+|-> => resize pane.                      

src/tests/e2e/snapshots/zellij__tests__e2e__cases__status_bar_loads_custom_keybindings.snap

@@ -1,6 +1,6 @@
 ---
 source: src/tests/e2e/cases.rs
-assertion_line: 398
+assertion_line: 987
 expression: last_snapshot
 ---
  Zellij (e2e-test)  Tab #1                                                                                            
@@ -25,5 +25,5 @@ expression: last_snapshot
 │                                                                                                                      │
 │                                                                                                                      │
 └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
- <F1> LOCK  <F2> PANE  <F3> TAB  <F4> RESIZE  <F5> MOVE  <F6> SEARCH  <F7> SESSION  <F8> QUIT            
+ <F1> LOCK  <F2> PANE  <F3> TAB  <F4> RESIZE  <F5> MOVE  <F6> SEARCH  <F7> SESSION  <F8> QUIT    BASE  
  Tip: UNBOUND => open new pane. UNBOUND => navigate between panes. UNBOUND => increase/decrease pane size.              

src/tests/e2e/snapshots/zellij__tests__e2e__cases__undo_rename_pane.snap

@@ -1,6 +1,6 @@
 ---
 source: src/tests/e2e/cases.rs
-assertion_line: 1949
+assertion_line: 1881
 expression: last_snapshot
 ---
  Zellij (e2e-test)  Tab #1                                                                                            
@@ -25,5 +25,5 @@ expression: last_snapshot
 │                                                                                                                      │
 │                                                                                                                      │
 └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
- Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT           
+ Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT  BASE   
  Tip: Alt + <n> => new pane. Alt + <←↓↑→> or Alt + <hjkl> => navigate. Alt + <+|-> => resize pane.                      

src/tests/e2e/snapshots/zellij__tests__e2e__cases__undo_rename_tab.snap

@@ -1,6 +1,6 @@
 ---
 source: src/tests/e2e/cases.rs
-assertion_line: 1900
+assertion_line: 1832
 expression: last_snapshot
 ---
  Zellij (e2e-test)  Tab #1                                                                                            
@@ -25,5 +25,5 @@ expression: last_snapshot
 │                                                                                                                      │
 │                                                                                                                      │
 └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
- Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT           
+ Ctrl + <g> LOCK  <p> PANE  <t> TAB  <n> RESIZE  <h> MOVE  <s> SEARCH  <o> SESSION  <q> QUIT  BASE   
  Tip: Alt + <n> => new pane. Alt + <←↓↑→> or Alt + <hjkl> => navigate. Alt + <+|-> => resize pane.                      

zellij-server/src/background_jobs.rs

@@ -2,6 +2,10 @@ use zellij_utils::async_std::task;
 use zellij_utils::errors::{prelude::*, BackgroundJobContext, ContextType};
 
 use std::collections::HashMap;
+use std::sync::{
+    atomic::{AtomicBool, Ordering},
+    Arc,
+};
 use std::time::{Duration, Instant};
 
 use crate::panes::PaneId;
@@ -11,23 +15,31 @@ use crate::thread_bus::Bus;
 #[derive(Debug, Clone, Eq, PartialEq, Hash)]
 pub enum BackgroundJob {
     DisplayPaneError(Vec<PaneId>, String),
+    AnimatePluginLoading(u32),       // u32 - plugin_id
+    StopPluginLoadingAnimation(u32), // u32 - plugin_id
     Exit,
 }
 
 impl From<&BackgroundJob> for BackgroundJobContext {
     fn from(background_job: &BackgroundJob) -> Self {
         match *background_job {
             BackgroundJob::DisplayPaneError(..) => BackgroundJobContext::DisplayPaneError,
+            BackgroundJob::AnimatePluginLoading(..) => BackgroundJobContext::AnimatePluginLoading,
+            BackgroundJob::StopPluginLoadingAnimation(..) => {
+                BackgroundJobContext::StopPluginLoadingAnimation
+            },
             BackgroundJob::Exit => BackgroundJobContext::Exit,
         }
     }
 }
 
 static FLASH_DURATION_MS: u64 = 1000;
+static PLUGIN_ANIMATION_OFFSET_DURATION_MD: u64 = 500;
 
 pub(crate) fn background_jobs_main(bus: Bus<BackgroundJob>) -> Result<()> {
     let err_context = || "failed to write to pty".to_string();
     let mut running_jobs: HashMap<BackgroundJob, Instant> = HashMap::new();
+    let mut loading_plugins: HashMap<u32, Arc<AtomicBool>> = HashMap::new(); // u32 - plugin_id
 
     loop {
         let (event, mut err_ctx) = bus.recv().with_context(err_context)?;
@@ -54,7 +66,37 @@ pub(crate) fn background_jobs_main(bus: Bus<BackgroundJob>) -> Result<()> {
                     }
                 });
             },
+            BackgroundJob::AnimatePluginLoading(pid) => {
+                let loading_plugin = Arc::new(AtomicBool::new(true));
+                if job_already_running(job, &mut running_jobs) {
+                    continue;
+                }
+                task::spawn({
+                    let senders = bus.senders.clone();
+                    let loading_plugin = loading_plugin.clone();
+                    async move {
+                        while loading_plugin.load(Ordering::SeqCst) {
+                            let _ = senders.send_to_screen(
+                                ScreenInstruction::ProgressPluginLoadingOffset(pid),
+                            );
+                            task::sleep(std::time::Duration::from_millis(
+                                PLUGIN_ANIMATION_OFFSET_DURATION_MD,
+                            ))
+                            .await;
+                        }
+                    }
+                });
+                loading_plugins.insert(pid, loading_plugin);
+            },
+            BackgroundJob::StopPluginLoadingAnimation(pid) => {
+                if let Some(loading_plugin) = loading_plugins.remove(&pid) {
+                    loading_plugin.store(false, Ordering::SeqCst);
+                }
+            },
             BackgroundJob::Exit => {
+                for loading_plugin in loading_plugins.values() {
+                    loading_plugin.store(false, Ordering::SeqCst);
+                }
                 return Ok(());
             },
         }

zellij-server/src/panes/plugin_pane.rs

@@ -6,7 +6,10 @@ use crate::panes::{grid::Grid, sixel::SixelImageStore, LinkHandler, PaneId};
 use crate::plugins::PluginInstruction;
 use crate::pty::VteBytes;
 use crate::tab::Pane;
-use crate::ui::pane_boundaries_frame::{FrameParams, PaneFrame};
+use crate::ui::{
+    loading_indication::LoadingIndication,
+    pane_boundaries_frame::{FrameParams, PaneFrame},
+};
 use crate::ClientId;
 use std::cell::RefCell;
 use std::rc::Rc;
@@ -67,6 +70,7 @@ pub(crate) struct PluginPane {
     borderless: bool,
     pane_frame_color_override: Option<(PaletteColor, Option<String>)>,
     invoked_with: Option<Run>,
+    loading_indication: LoadingIndication,
 }
 
 impl PluginPane {
@@ -81,10 +85,13 @@ impl PluginPane {
         terminal_emulator_color_codes: Rc<RefCell<HashMap<usize, String>>>,
         link_handler: Rc<RefCell<LinkHandler>>,
         character_cell_size: Rc<RefCell<Option<SizeInPixels>>>,
+        currently_connected_clients: Vec<ClientId>,
         style: Style,
         invoked_with: Option<Run>,
     ) -> Self {
-        Self {
+        let loading_indication = LoadingIndication::new(title.clone()).with_colors(style.colors);
+        let initial_loading_message = loading_indication.to_string();
+        let mut plugin = PluginPane {
             pid,
             should_render: HashMap::new(),
             selectable: true,
@@ -108,7 +115,12 @@ impl PluginPane {
             style,
             pane_frame_color_override: None,
             invoked_with,
+            loading_indication,
+        };
+        for client_id in currently_connected_clients {
+            plugin.handle_plugin_bytes(client_id, initial_loading_message.as_bytes().to_vec());
         }
+        plugin
     }
 }
 
@@ -513,6 +525,24 @@ impl Pane for PluginPane {
     fn set_title(&mut self, title: String) {
         self.pane_title = title;
     }
+    fn update_loading_indication(&mut self, loading_indication: LoadingIndication) {
+        if self.loading_indication.ended {
+            return;
+        }
+        self.loading_indication.merge(loading_indication);
+        self.handle_plugin_bytes_for_all_clients(
+            self.loading_indication.to_string().as_bytes().to_vec(),
+        );
+    }
+    fn progress_animation_offset(&mut self) {
+        if self.loading_indication.ended {
+            return;
+        }
+        self.loading_indication.progress_animation_offset();
+        self.handle_plugin_bytes_for_all_clients(
+            self.loading_indication.to_string().as_bytes().to_vec(),
+        );
+    }
 }
 
 impl PluginPane {
@@ -527,4 +557,10 @@ impl PluginPane {
     fn set_client_should_render(&mut self, client_id: ClientId, should_render: bool) {
         self.should_render.insert(client_id, should_render);
     }
+    fn handle_plugin_bytes_for_all_clients(&mut self, bytes: VteBytes) {
+        let client_ids: Vec<ClientId> = self.grids.keys().copied().collect();
+        for client_id in client_ids {
+            self.handle_plugin_bytes(client_id, bytes.clone());
+        }
+    }
 }

zellij-server/src/plugins/mod.rs

@@ -1,8 +1,10 @@
+mod start_plugin;
 mod wasm_bridge;
 use log::info;
 use std::{collections::HashMap, fs, path::PathBuf};
 use wasmer::Store;
 
+use crate::screen::ScreenInstruction;
 use crate::{pty::PtyInstruction, thread_bus::Bus, ClientId};
 
 use wasm_bridge::WasmBridge;
@@ -20,7 +22,14 @@ use zellij_utils::{
 
 #[derive(Clone, Debug)]
 pub enum PluginInstruction {
-    Load(RunPlugin, usize, ClientId, Size), // plugin metadata, tab_index, client_ids
+    Load(
+        Option<bool>,   // should float
+        Option<String>, // pane title
+        RunPlugin,
+        usize, // tab index
+        ClientId,
+        Size,
+    ),
     Update(Vec<(Option<u32>, Option<ClientId>, Event)>), // Focused plugin / broadcast, client_id, event data
     Unload(u32),                                         // plugin_id
     Resize(u32, usize, usize),                           // plugin_id, columns, rows
@@ -33,6 +42,7 @@ pub enum PluginInstruction {
         usize, // tab_index
         ClientId,
     ),
+    ApplyCachedEvents(u32), // u32 is the plugin id
     Exit,
 }
 
@@ -47,6 +57,7 @@ impl From<&PluginInstruction> for PluginContext {
             PluginInstruction::AddClient(_) => PluginContext::AddClient,
             PluginInstruction::RemoveClient(_) => PluginContext::RemoveClient,
             PluginInstruction::NewTab(..) => PluginContext::NewTab,
+            PluginInstruction::ApplyCachedEvents(..) => PluginContext::ApplyCachedEvents,
         }
     }
 }
@@ -69,8 +80,21 @@ pub(crate) fn plugin_thread_main(
         let (event, mut err_ctx) = bus.recv().expect("failed to receive event on channel");
         err_ctx.add_call(ContextType::Plugin((&event).into()));
         match event {
-            PluginInstruction::Load(run, tab_index, client_id, size) => {
-                wasm_bridge.load_plugin(&run, tab_index, size, client_id)?;
+            PluginInstruction::Load(should_float, pane_title, run, tab_index, client_id, size) => {
+                match wasm_bridge.load_plugin(&run, tab_index, size, client_id) {
+                    Ok(plugin_id) => {
+                        drop(bus.senders.send_to_screen(ScreenInstruction::AddPlugin(
+                            should_float,
+                            run,
+                            pane_title,
+                            tab_index,
+                            plugin_id,
+                        )));
+                    },
+                    Err(e) => {
+                        log::error!("Failed to load plugin: {e}");
+                    },
+                }
             },
             PluginInstruction::Update(updates) => {
                 wasm_bridge.update_plugins(updates)?;
@@ -126,7 +150,13 @@ pub(crate) fn plugin_thread_main(
                     client_id,
                 )));
             },
-            PluginInstruction::Exit => break,
+            PluginInstruction::ApplyCachedEvents(plugin_id) => {
+                wasm_bridge.apply_cached_events(plugin_id)?;
+            },
+            PluginInstruction::Exit => {
+                wasm_bridge.cleanup();
+                break;
+            },
         }
     }
     info!("wasm main thread exits");