feat(plugins): Plugin workers and strider (#2449)

* mvp of strider fuzzy find

* improve search ui

* various refactoringz

* moar refactoring

* even more refactoring

* tests and more refactoring

* refactor: remove unused stuff

* style(fmt): rustfmt

* debug ci

* debug ci

* correct path for plugin system tests

* fix plugin system ci tests

* remove debugging statements from test

* fix plugin worker persistence

* add test for plugin worker persistence

* style(fmt): rustfmt

* final cleanups

* remove outdated comments

34 files changed, 1926 insertions, 186 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 74374912a..33c762962 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -776,11 +776,12 @@ checksum = "3c877555693c14d2f84191cfd3ad8582790fc52b5e2274b40b59cf5f5cea25c7"
 
 [[package]]
 name = "dialoguer"
-version = "0.10.1"
+version = "0.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d8c8ae48e400addc32a8710c8d62d55cb84249a7d58ac4cd959daecfbaddc545"
+checksum = "59c6f2989294b9a498d3ad5491a79c6deb604617378e1cdc4bfc1c1361fe2f87"
 dependencies = [
  "console",
+ "shell-words",
  "tempfile",
  "zeroize",
 ]
@@ -1020,6 +1021,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
 
 [[package]]
+name = "fixture-plugin-for-tests"
+version = "0.1.0"
+dependencies = [
+ "serde",
+ "serde_json",
+ "zellij-tile",
+]
+
+[[package]]
 name = "fnv"
 version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1072,6 +1082,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "fuzzy-matcher"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "54614a3312934d066701a80f20f15fa3b56d67ac7722b39eea5b4c9dd1d66c94"
+dependencies = [
+ "thread_local",
+]
+
+[[package]]
 name = "generational-arena"
 version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2444,6 +2463,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f3f6f92acf49d1b98f7a81226834412ada05458b7364277387724a237f062695"
 
 [[package]]
+name = "same-file"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
+dependencies = [
+ "winapi-util",
+]
+
+[[package]]
 name = "scopeguard"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2597,6 +2625,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "shell-words"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24188a676b6ae68c3b2cb3a01be17fbf7240ce009799bb56d5b1409051e78fde"
+
+[[package]]
 name = "shellexpand"
 version = "3.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2798,8 +2832,14 @@ checksum = "213701ba3370744dcd1a12960caa4843b3d68b4d1c0a5d575e0d65b2ee9d16c0"
 name = "strider"
 version = "0.2.0"
 dependencies = [
+ "ansi_term",
  "colored",
+ "fuzzy-matcher",
  "pretty-bytes",
+ "serde",
+ "serde_json",
+ "unicode-width",
+ "walkdir",
  "zellij-tile",
 ]
 
@@ -3067,6 +3107,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "thread_local"
+version = "1.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fdd6f064ccff2d6567adcb3873ca630700f00b5ad3f060c25b5dcfd9a4ce152"
+dependencies = [
+ "cfg-if 1.0.0",
+ "once_cell",
+]
+
+[[package]]
 name = "time"
 version = "0.1.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -3372,6 +3422,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9d5b2c62b4012a3e1eca5a7e077d13b3bf498c4073e33ccd58626607748ceeca"
 
 [[package]]
+name = "walkdir"
+version = "2.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36df944cda56c7d8d8b7496af378e6b16de9284591917d307c9b4d313c44e698"
+dependencies = [
+ "same-file",
+ "winapi-util",
+]
+
+[[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -4212,6 +4272,7 @@ dependencies = [
  "sixel-image",
  "sixel-tokenizer",
  "sysinfo",
+ "tempfile",
  "typetag",
  "unicode-width",
  "url",
@@ -4278,6 +4339,7 @@ dependencies = [
  "thiserror",
  "unicode-width",
  "url",
+ "uuid",
  "vte 0.11.0",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index 1c16269f2..1ce85c77f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,6 +34,7 @@ members = [
     "default-plugins/status-bar",
     "default-plugins/strider",
     "default-plugins/tab-bar",
+    "default-plugins/fixture-plugin-for-tests",
     "zellij-client",
     "zellij-server",
     "zellij-utils",
diff --git a/default-plugins/fixture-plugin-for-tests/.cargo/config.toml b/default-plugins/fixture-plugin-for-tests/.cargo/config.toml
new file mode 100644
index 000000000..bc255e30b
--- /dev/null
+++ b/default-plugins/fixture-plugin-for-tests/.cargo/config.toml
@@ -0,0 +1,2 @@
+[build]
+target = "wasm32-wasi"
\ No newline at end of file
diff --git a/default-plugins/fixture-plugin-for-tests/Cargo.toml b/default-plugins/fixture-plugin-for-tests/Cargo.toml
new file mode 100644
index 000000000..39211c340
--- /dev/null
+++ b/default-plugins/fixture-plugin-for-tests/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "fixture-plugin-for-tests"
+version = "0.1.0"
+authors = ["Aram Drevekenin <aram@poor.dev>"]
+edition = "2021"
+license = "MIT"
+
+[dependencies]
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
+zellij-tile = { path = "../../zellij-tile" }
diff --git a/default-plugins/fixture-plugin-for-tests/LICENSE.md b/default-plugins/fixture-plugin-for-tests/LICENSE.md
new file mode 120000
index 000000000..f0608a63a
--- /dev/null
+++ b/default-plugins/fixture-plugin-for-tests/LICENSE.md
@@ -0,0 +1 @@
+../../LICENSE.md
\ No newline at end of file
diff --git a/default-plugins/fixture-plugin-for-tests/src/main.rs b/default-plugins/fixture-plugin-for-tests/src/main.rs
new file mode 100644
index 000000000..124b2dc75
--- /dev/null
+++ b/default-plugins/fixture-plugin-for-tests/src/main.rs
@@ -0,0 +1,78 @@
+use serde::{Deserialize, Serialize};
+use zellij_tile::prelude::*;
+
+// This is a fixture plugin used only for tests in Zellij
+// it is not (and should not!) be included in the mainline executable
+// it's included here for convenience so that it will be built by the CI
+
+#[derive(Default)]
+struct State {
+    received_events: Vec<Event>,
+    received_payload: Option<String>,
+}
+
+#[derive(Default, Serialize, Deserialize)]
+struct TestWorker {
+    number_of_messages_received: usize,
+}
+
+impl<'de> ZellijWorker<'de> for TestWorker {
+    fn on_message(&mut self, message: String, payload: String) {
+        if message == "ping" {
+            self.number_of_messages_received += 1;
+            post_message_to_plugin(
+                "pong".into(),
+                format!(
+                    "{}, received {} messages",
+                    payload, self.number_of_messages_received
+                ),
+            );
+        }
+    }
+}
+
+register_plugin!(State);
+register_worker!(TestWorker, test_worker);
+
+impl ZellijPlugin for State {
+    fn load(&mut self) {
+        subscribe(&[
+            EventType::InputReceived,
+            EventType::SystemClipboardFailure,
+            EventType::CustomMessage,
+        ]);
+    }
+
+    fn update(&mut self, event: Event) -> bool {
+        match &event {
+            Event::CustomMessage(message, payload) => {
+                if message == "pong" {
+                    self.received_payload = Some(payload.clone());
+                }
+            },
+            Event::SystemClipboardFailure => {
+                // this is just to trigger the worker message
+                post_message_to(
+                    "test",
+                    "ping".to_owned(),
+                    "gimme_back_my_payload".to_owned(),
+                );
+            },
+            _ => {},
+        }
+        let should_render = true;
+        self.received_events.push(event);
+        should_render
+    }
+
+    fn render(&mut self, rows: usize, cols: usize) {
+        if let Some(payload) = self.received_payload.as_ref() {
+            println!("Payload from worker: {:?}", payload);
+        } else {
+            println!(
+                "Rows: {:?}, Cols: {:?}, Received events: {:?}",
+                rows, cols, self.received_events
+            );
+        }
+    }
+}
diff --git a/default-plugins/strider/Cargo.toml b/default-plugins/strider/Cargo.toml
index f7801bfaf..d45a8ff21 100644
--- a/default-plugins/strider/Cargo.toml
+++ b/default-plugins/strider/Cargo.toml
@@ -10,3 +10,9 @@ license = "MIT"
 colored = "2.0.0"
 zellij-tile = { path = "../../zellij-tile" }
 pretty-bytes = "0.2.2"
+walkdir = "2.3.3"
+fuzzy-matcher = "0.3.7"
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
+unicode-width = "0.1.8"
+ansi_term = "0.12.1"
diff --git a/default-plugins/strider/src/main.rs b/default-plugins/strider/src/main.rs
index 6868c6706..4f299c508 100644
--- a/default-plugins/strider/src/main.rs
+++ b/default-plugins/strider/src/main.rs
@@ -1,16 +1,28 @@
+mod search;
 mod state;
 
 use colored::*;
-use state::{refresh_directory, FsEntry, State};
+use search::{ResultsOfSearch, SearchWorker};
+use serde_json;
+use state::{refresh_directory, FsEntry, State, CURRENT_SEARCH_TERM};
 use std::{cmp::min, time::Instant};
 use zellij_tile::prelude::*;
 
 register_plugin!(State);
+register_worker!(SearchWorker, search_worker);
 
 impl ZellijPlugin for State {
     fn load(&mut self) {
         refresh_directory(self);
-        subscribe(&[EventType::Key, EventType::Mouse]);
+        self.loading = true;
+        subscribe(&[
+            EventType::Key,
+            EventType::Mouse,
+            EventType::CustomMessage,
+            EventType::Timer,
+        ]);
+        post_message_to("search", String::from("scan_folder"), String::new());
+        set_timeout(0.5); // for displaying loading animation
     }
 
     fn update(&mut self, event: Event) -> bool {
@@ -22,26 +34,101 @@ impl ZellijPlugin for State {
         };
         self.ev_history.push_back((event.clone(), Instant::now()));
         match event {
+            Event::Timer(_elapsed) => {
+                should_render = true;
+                if self.loading {
+                    set_timeout(0.5);
+                    if self.loading_animation_offset == u8::MAX {
+                        self.loading_animation_offset = 0;
+                    } else {
+                        self.loading_animation_offset =
+                            self.loading_animation_offset.saturating_add(1);
+                    }
+                }
+            },
+            Event::CustomMessage(message, payload) => match message.as_str() {
+                "update_search_results" => {
+                    if let Ok(mut results_of_search) =
+                        serde_json::from_str::<ResultsOfSearch>(&payload)
+                    {
+                        if Some(results_of_search.search_term) == self.search_term {
+                            self.search_results =
+                                results_of_search.search_results.drain(..).collect();
+                            should_render = true;
+                        }
+                    }
+                },
+                "done_scanning_folder" => {
+                    self.loading = false;
+                    should_render = true;
+                },
+                _ => {},
+            },
             Event::Key(key) => match key {
+                // modes:
+                // 1. typing_search_term
+                // 2. exploring_search_results
+                // 3. normal
+                Key::Esc | Key::Char('\n') if self.typing_search_term() => {
+                    self.accept_search_term();
+                },
+                _ if self.typing_search_term() => {
+                    self.append_to_search_term(key);
+                    if let Some(search_term) = self.search_term.as_ref() {
+                        std::fs::write(CURRENT_SEARCH_TERM, search_term.as_bytes()).unwrap();
+                        post_message_to(
+                            "search",
+                            String::from("search"),
+                            String::from(&self.search_term.clone().unwrap()),
+                        );
+                    }
+                    should_render = true;
+                },
+                Key::Esc if self.exploring_search_results() => {
+                    self.stop_exploring_search_results();
+                    should_render = true;
+                },
+                Key::Char('/') => {
+                    self.start_typing_search_term();
+                    should_render = true;
+                },
+                Key::Esc => {
+                    self.stop_typing_search_term();
+                    should_render = true;
+                },
                 Key::Up | Key::Char('k') => {
-                    let currently_selected = self.selected();
-                    *self.selected_mut() = self.selected().saturating_sub(1);
-                    if currently_selected != self.selected() {
+                    if self.exploring_search_results() {
+                        self.move_search_selection_up();
                         should_render = true;
+                    } else {
+                        let currently_selected = self.selected();
+                        *self.selected_mut() = self.selected().saturating_sub(1);
+                        if currently_selected != self.selected() {
+                            should_render = true;
+                        }
                     }
                 },
                 Key::Down | Key::Char('j') => {
-                    let currently_selected = self.selected();
-                    let next = self.selected().saturating_add(1);
-                    *self.selected_mut() = min(self.files.len().saturating_sub(1), next);
-                    if currently_selected != self.selected() {
+                    if self.exploring_search_results() {
+                        self.move_search_selection_down();
                         should_render = true;
+                    } else {
+                        let currently_selected = self.selected();
+                        let next = self.selected().saturating_add(1);
+                        *self.selected_mut() = min(self.files.len().saturating_sub(1), next);
+                        if currently_selected != self.selected() {
+                            should_render = true;
+                        }
                     }
                 },
                 Key::Right | Key::Char('\n') | Key::Char('l') if !self.files.is_empty() => {
+                    if self.exploring_search_results() {
+                        self.open_search_result();
+                    } else {
+                        self.traverse_dir_or_open_file();
+                        self.ev_history.clear();
+                    }
                     should_render = true;
-                    self.traverse_dir_or_open_file();
-                    self.ev_history.clear();
                 },
                 Key::Left | Key::Char('h') => {
                     if self.path.components().count() > 2 {
@@ -111,6 +198,10 @@ impl ZellijPlugin for State {
     }
 
     fn render(&mut self, rows: usize, cols: usize) {
+        if self.typing_search_term() || self.exploring_search_results() {
+            return self.render_search(rows, cols);
+        }
+
         for i in 0..rows {
             if self.selected() < self.scroll() {
                 *self.scroll_mut() = self.selected();
diff --git a/default-plugins/strider/src/search.rs b/default-plugins/strider/src/search.rs
new file mode 100644
index 000000000..299882eac
--- /dev/null
+++ b/default-plugins/strider/src/search.rs
@@ -0,0 +1,415 @@
+use crate::state::{State, CURRENT_SEARCH_TERM, ROOT};
+
+use unicode_width::UnicodeWidthStr;
+use zellij_tile::prelude::*;
+
+use fuzzy_matcher::skim::SkimMatcherV2;
+use fuzzy_matcher::FuzzyMatcher;
+use serde::{Deserialize, Serialize};
+use walkdir::WalkDir;
+
+use std::io::{self, BufRead};
+
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub enum SearchResult {
+    File {
+        path: String,
+        score: i64,
+        indices: Vec<usize>,
+    },
+    LineInFile {
+        path: String,
+        line: String,
+        line_number: usize,
+        score: i64,
+        indices: Vec<usize>,
+    },
+}
+
+impl SearchResult {
+    pub fn new_file_name(score: i64, indices: Vec<usize>, path: String) -> Self {
+        SearchResult::File {
+            path,
+            score,
+            indices,
+        }
+    }
+    pub fn new_file_line(
+        score: i64,
+        indices: Vec<usize>,
+        path: String,
+        line: String,
+        line_number: usize,
+    ) -> Self {
+        SearchResult::LineInFile {
+            path,
+            score,
+            indices,
+            line,
+            line_number,
+        }
+    }
+    pub fn score(&self) -> i64 {
+        match self {
+            SearchResult::File { score, .. } => *score,
+            SearchResult::LineInFile { score, .. } => *score,
+        }
+    }
+    pub fn rendered_height(&self) -> usize {
+        match self {
+            SearchResult::File { .. } => 1,
+            SearchResult::LineInFile { .. } => 2,
+        }
+    }
+    pub fn render(&self, max_width: usize, is_selected: bool) -> String {
+        let green_code = 154;
+        let orange_code = 166;
+        let bold_code = "\u{1b}[1m";
+        let green_foreground = format!("\u{1b}[38;5;{}m", green_code);
+        let orange_foreground = format!("\u{1b}[38;5;{}m", orange_code);
+        let reset_code = "\u{1b}[m";
+        let max_width = max_width.saturating_sub(3); // for the UI left line separator
+        match self {
+            SearchResult::File { path, indices, .. } => {
+                if is_selected {
+                    let line = self.render_line_with_indices(
+                        path,
+