feat(plugin): Add mouse events for plugins (#629)

* feat(plugin): Add mouse events for plugins

* Add double click support in strider

* Add support for mouse clicks in tab-bar and fix bug in strider with selecting past the list of files and random double click action

* continue working on mouse support for tab bar

* finish tab change

* fix fmt and fix bug in strider double-click

* fix clippy

* cleanup dbgs and logs

* fix clippy

* noop change to rerun e2e tests

* Rebase and fix mouse click behavior in tab-bar and strider after rebase

* fix fmt

* remove dbgs and and comment in tab-line/main.rs

* cargo fmt

* Code review suggestions

* rebase fix

* fix clippy

* fix mouse selection for tabs in tab-bar

3 files changed, 133 insertions, 42 deletions

diff --git a/default-plugins/strider/src/main.rs b/default-plugins/strider/src/main.rs
index f0b5cebfc..3bdceefdd 100644
--- a/default-plugins/strider/src/main.rs
+++ b/default-plugins/strider/src/main.rs
@@ -1,23 +1,27 @@
 mod state;
 
 use colored::*;
-use state::{FsEntry, State};
-use std::{cmp::min, fs::read_dir, path::Path};
+use state::{refresh_directory, FsEntry, State};
+use std::{cmp::min, time::Instant};
 use zellij_tile::prelude::*;
 
-const ROOT: &str = "/host";
-
 register_plugin!(State);
 
 impl ZellijPlugin for State {
     fn load(&mut self) {
         refresh_directory(self);
-        subscribe(&[EventType::KeyPress]);
+        subscribe(&[EventType::KeyPress, EventType::Mouse]);
     }
 
     fn update(&mut self, event: Event) {
-        if let Event::KeyPress(key) = event {
-            match key {
+        let prev_event = if self.ev_history.len() == 2 {
+            self.ev_history.pop_front()
+        } else {
+            None
+        };
+        self.ev_history.push_back((event.clone(), Instant::now()));
+        match event {
+            Event::KeyPress(key) => match key {
                 Key::Up | Key::Char('k') => {
                     *self.selected_mut() = self.selected().saturating_sub(1);
                 }
@@ -26,13 +30,8 @@ impl ZellijPlugin for State {
                     *self.selected_mut() = min(self.files.len() - 1, next);
                 }
                 Key::Right | Key::Char('\n') | Key::Char('l') if !self.files.is_empty() => {
-                    match self.files[self.selected()].clone() {
-                        FsEntry::Dir(p, _) => {
-                            self.path = p;
-                            refresh_directory(self);
-                        }
-                        FsEntry::File(p, _) => open_file(p.strip_prefix(ROOT).unwrap()),
-                    }
+                    self.traverse_dir_or_open_file();
+                    self.ev_history.clear();
                 }
                 Key::Left | Key::Char('h') => {
                     if self.path.components().count() > 2 {
@@ -44,25 +43,59 @@ impl ZellijPlugin for State {
                         refresh_directory(self);
                     }
                 }
-
                 Key::Char('.') => {
                     self.toggle_hidden_files();
                     refresh_directory(self);
                 }
 
                 _ => (),
-            };
+            },
+            Event::Mouse(mouse_event) => match mouse_event {
+                Mouse::ScrollDown(_) => {
+                    let next = self.selected().saturating_add(1);
+                    *self.selected_mut() = min(self.files.len().saturating_sub(1), next);
+                }
+                Mouse::ScrollUp(_) => {
+                    *self.selected_mut() = self.selected().saturating_sub(1);
+                }
+                Mouse::MouseRelease(Some((line, _))) => {
+                    if line < 0 {
+                        return;
+                    }
+                    let mut should_select = true;
+                    if let Some((Event::Mouse(Mouse::MouseRelease(Some((prev_line, _)))), t)) =
+                        prev_event
+                    {
+                        if prev_line == line
+                            && Instant::now().saturating_duration_since(t).as_millis() < 400
+                        {
+                            self.traverse_dir_or_open_file();
+                            self.ev_history.clear();
+                            should_select = false;
+                        }
+                    }
+                    if should_select && self.scroll() + (line as usize) < self.files.len() {
+                        *self.selected_mut() = self.scroll() + (line as usize);
+                    }
+                }
+                _ => {}
+            },
+            _ => {
+                dbg!("Unknown event {:?}", event);
+            }
         }
     }
 
     fn render(&mut self, rows: usize, cols: usize) {
         for i in 0..rows {
+            // If the key was pressed, set selected so that we can see the cursor
             if self.selected() < self.scroll() {
                 *self.scroll_mut() = self.selected();
             }
             if self.selected() - self.scroll() + 2 > rows {
                 *self.scroll_mut() = self.selected() + 2 - rows;
             }
+
             let i = self.scroll() + i;
             if let Some(entry) = self.files.get(i) {
                 let mut path = entry.as_line(cols).normal();
@@ -82,24 +115,3 @@ impl ZellijPlugin for State {
         }
     }
 }
-
-fn refresh_directory(state: &mut State) {
-    state.files = read_dir(Path::new(ROOT).join(&state.path))
-        .unwrap()
-        .filter_map(|res| {
-            res.and_then(|d| {
-                if d.metadata()?.is_dir() {
-                    let children = read_dir(d.path())?.count();
-                    Ok(FsEntry::Dir(d.path(), children))
-                } else {
-                    let size = d.metadata()?.len();
-                    Ok(FsEntry::File(d.path(), size))
-                }
-            })
-            .ok()
-            .filter(|d| !d.is_hidden_file() || !state.hide_hidden_files)
-        })
-        .collect();
-
-    state.files.sort_unstable();
-}
diff --git a/default-plugins/strider/src/state.rs b/default-plugins/strider/src/state.rs
index 0ae84ab29..7c19cb695 100644
--- a/default-plugins/strider/src/state.rs
+++ b/default-plugins/strider/src/state.rs
@@ -1,12 +1,20 @@
 use pretty_bytes::converter as pb;
-use std::{collections::HashMap, path::PathBuf};
+use std::{
+    collections::{HashMap, VecDeque},
+    fs::read_dir,
+    path::{Path, PathBuf},
+    time::Instant,
+};
+use zellij_tile::prelude::*;
 
+const ROOT: &str = "/host";
 #[derive(Default)]
 pub struct State {
     pub path: PathBuf,
     pub files: Vec<FsEntry>,
     pub cursor_hist: HashMap<PathBuf, (usize, usize)>,
     pub hide_hidden_files: bool,
+    pub ev_history: VecDeque<(Event, Instant)>, // stores last event, can be expanded in future
 }
 
 impl State {
@@ -25,6 +33,15 @@ impl State {
     pub fn toggle_hidden_files(&mut self) {
         self.hide_hidden_files = !self.hide_hidden_files;
     }
+    pub fn traverse_dir_or_open_file(&mut self) {
+        match self.files[self.selected()].clone() {
+            FsEntry::Dir(p, _) => {
+                self.path = p;
+                refresh_directory(self);
+            }
+            FsEntry::File(p, _) => open_file(p.strip_prefix(ROOT).unwrap()),
+        }
+    }
 }
 
 #[derive(PartialEq, Eq, PartialOrd, Ord, Clone)]
@@ -61,3 +78,24 @@ impl FsEntry {
         self.name().starts_with('.')
     }
 }
+
+pub(crate) fn refresh_directory(state: &mut State) {
+    state.files = read_dir(Path::new(ROOT).join(&state.path))
+        .unwrap()
+        .filter_map(|res| {
+            res.and_then(|d| {
+                if d.metadata()?.is_dir() {
+                    let children = read_dir(d.path())?.count();
+                    Ok(FsEntry::Dir(d.path(), children))
+                } else {
+                    let size = d.metadata()?.len();
+                    Ok(FsEntry::File(d.path(), size))
+                }
+            })
+            .ok()
+            .filter(|d| !d.is_hidden_file() || !state.hide_hidden_files)
+        })
+        .collect();
+
+    state.files.sort_unstable();
+}
diff --git a/default-plugins/tab-bar/src/main.rs b/default-plugins/tab-bar/src/main.rs
index 850781261..c34693523 100644
--- a/default-plugins/tab-bar/src/main.rs
+++ b/default-plugins/tab-bar/src/main.rs
@@ -1,6 +1,9 @@
 mod line;
 mod tab;
 
+use std::cmp::{max, min};
+use std::convert::TryInto;
+
 use zellij_tile::prelude::*;
 
 use crate::line::tab_line;
@@ -15,7 +18,10 @@ pub struct LinePart {
 #[derive(Default)]
 struct State {
     tabs: Vec<TabInfo>,
+    active_tab_idx: usize,
     mode_info: ModeInfo,
+    mouse_click_pos: usize,
+    should_render: bool,
 }
 
 static ARROW_SEPARATOR: &str = "";
@@ -25,13 +31,34 @@ register_plugin!(State);
 impl ZellijPlugin for State {
     fn load(&mut self) {
         set_selectable(false);
-        subscribe(&[EventType::TabUpdate, EventType::ModeUpdate]);
+        subscribe(&[
+            EventType::TabUpdate,
+            EventType::ModeUpdate,
+            EventType::Mouse,
+        ]);
     }
 
     fn update(&mut self, event: Event) {
         match event {
             Event::ModeUpdate(mode_info) => self.mode_info = mode_info,
-            Event::TabUpdate(tabs) => self.tabs = tabs,
+            Event::TabUpdate(tabs) => {
+                // tabs are indexed starting from 1 so we need to add 1
+                self.active_tab_idx = (&tabs).iter().position(|t| t.active).unwrap() + 1;
+                self.tabs = tabs;
+            }
+            Event::Mouse(me) => match me {
+                Mouse::LeftClick(_, col) => {
+                    self.mouse_click_pos = col;
+                    self.should_render = true;
+                }
+                Mouse::ScrollUp(_) => {
+                    switch_tab_to(min(self.active_tab_idx + 1, self.tabs.len()) as u32);
+                }
+                Mouse::ScrollDown(_) => {
+                    switch_tab_to(max(self.active_tab_idx.saturating_sub(1), 1) as u32);
+                }
+                _ => {}
+            },
             _ => unimplemented!(), // FIXME: This should be unreachable, but this could be cleaner
         }
     }
@@ -70,8 +97,21 @@ impl ZellijPlugin for State {
             self.mode_info.capabilities,
         );
         let mut s = String::new();
-        for bar_part in tab_line {
-            s = format!("{}{}", s, bar_part.part);
+        let mut len_cnt = 0;
+        dbg!(&tab_line);
+        for (idx, bar_part) in tab_line.iter().enumerate() {
+            s = format!("{}{}", s, &bar_part.part);
+
+            if self.should_render
+                && self.mouse_click_pos > len_cnt
+                && self.mouse_click_pos <= len_cnt + bar_part.len
+                && idx > 2
+            {
+                // First three elements of tab_line are "Zellij", session name and empty thing, hence the idx > 2 condition.
+                // Tabs are indexed starting from 1, therefore we need subtract 2 below.
+                switch_tab_to(TryInto::<u32>::try_into(idx).unwrap() - 2);
+            }
+            len_cnt += bar_part.len;
         }
         match self.mode_info.palette.cyan {
             PaletteColor::Rgb((r, g, b)) => {
@@ -81,5 +121,6 @@ impl ZellijPlugin for State {
                 println!("{}\u{1b}[48;5;{}m\u{1b}[0K", s, color);
             }
         }
+        self.should_render = false;
     }
 }