fix(mouse): prevent unhandled mouse events escape to terminal (#976)

* workaround to not write csi mouse seqs to terminal

* tab: copy selection to clipboard only if selecting was initiated with left click

* cleanup debug log messages

* unset selecting_with_mouse when selection is empty

zellij-client/src/stdin_handler.rs

@@ -58,6 +58,7 @@ pub(crate) fn stdin_loop(
 ) {
     let mut pasting = false;
     let bracketed_paste_start = vec![27, 91, 50, 48, 48, 126]; // \u{1b}[200~
+    let csi_mouse_sgr_start = vec![27, 91, 60];
     let adjusted_keys = keys_to_adjust();
     loop {
         let mut stdin_buffer = os_input.read_from_stdin();
@@ -149,6 +150,19 @@ pub(crate) fn stdin_loop(
                     continue;
                 }
             }
+
+            // FIXME: termion does not properly parse some csi sgr mouse sequences
+            // like ctrl + click.
+            // As a workaround, to avoid writing these sequences to tty stdin,
+            // we discard them.
+            if let termion::event::Event::Unsupported(_) = key_event {
+                if raw_bytes.len() > csi_mouse_sgr_start.len()
+                    && raw_bytes[0..csi_mouse_sgr_start.len()] == csi_mouse_sgr_start
+                {
+                    continue;
+                }
+            }
+
             send_input_instructions
                 .send(InputInstruction::KeyEvent(key_event, raw_bytes))
                 .unwrap();

zellij-server/src/tab.rs

@@ -155,6 +155,7 @@ pub(crate) struct Tab {
     draw_pane_frames: bool,
     session_is_mirrored: bool,
     pending_vte_events: HashMap<RawFd, Vec<VteBytes>>,
+    selecting_with_mouse: bool,
 }
 
 #[derive(Clone, Debug, Default, Serialize, Deserialize)]
@@ -370,6 +371,7 @@ impl Tab {
             pending_vte_events: HashMap::new(),
             connected_clients_in_app,
             connected_clients,
+            selecting_with_mouse: false,
         }
     }
 
@@ -3368,6 +3370,7 @@ impl Tab {
         if let Some(pane) = self.get_pane_at(position, false) {
             let relative_position = pane.relative_position(position);
             pane.start_selection(&relative_position);
+            self.selecting_with_mouse = true;
         };
     }
     pub fn handle_right_click(&mut self, position: &Position, client_id: ClientId) {
@@ -3393,6 +3396,10 @@ impl Tab {
         }
     }
     pub fn handle_mouse_release(&mut self, position: &Position, client_id: ClientId) {
+        if !self.selecting_with_mouse {
+            return;
+        }
+
         let active_pane_id = self.get_active_pane_id(client_id);
         // on release, get the selected text from the active pane, and reset it's selection
         let mut selected_text = None;
@@ -3414,6 +3421,7 @@ impl Tab {
         if let Some(selected_text) = selected_text {
             self.write_selection_to_clipboard(&selected_text);
         }
+        self.selecting_with_mouse = false;
     }
     pub fn handle_mouse_hold(&mut self, position_on_screen: &Position, client_id: ClientId) {
         if let Some(active_pane_id) = self.get_active_pane_id(client_id) {