Terminal compatibility: forward OSC52 events (#1644)

Fixes #1199

Co-authored-by: Christian Schubert <christian.schubert01@sap.com>

zellij-server/src/panes/grid.rs

@@ -342,6 +342,7 @@ pub struct Grid {
     scrollback_buffer_lines: usize,
     pub mouse_mode: bool,
     pub search_results: SearchResult,
+    pub pending_clipboard_update: Option<String>,
 }
 
 impl Debug for Grid {
@@ -447,6 +448,7 @@ impl Grid {
             character_cell_size,
             search_results: Default::default(),
             sixel_grid,
+            pending_clipboard_update: None,
         }
     }
     pub fn render_full_viewport(&mut self) {
@@ -1890,8 +1892,12 @@ impl Perform for Grid {
                     b"?" => {
                         // TBD: paste from own clipboard - currently unsupported
                     },
-                    _base64 => {
+                    base64 => {
-                        // TBD: copy to own clipboard - currently unsupported
+                        if let Ok(bytes) = base64::decode(base64) {
+                            if let Ok(string) = String::from_utf8(bytes) {
+                                self.pending_clipboard_update = Some(string);
+                            }
+                        };
                     },
                 }
             },

zellij-server/src/panes/terminal_pane.rs

@@ -484,6 +484,10 @@ impl Pane for TerminalPane {
         self.grid.pending_messages_to_pty.drain(..).collect()
     }
 
+    fn drain_clipboard_update(&mut self) -> Option<String> {
+        self.grid.pending_clipboard_update.take()
+    }
+
     fn start_selection(&mut self, start: &Position, _client_id: ClientId) {
         self.grid.start_selection(start);
         self.set_should_render(true);

zellij-server/src/tab/mod.rs

@@ -258,6 +258,9 @@ pub trait Pane {
         // we should probably refactor away from this trait at some point
         vec![]
     }
+    fn drain_clipboard_update(&mut self) -> Option<String> {
+        None
+    }
     fn render_full_viewport(&mut self) {}
     fn relative_position(&self, position_on_screen: &Position) -> Position {
         position_on_screen.relative_to(self.get_content_y(), self.get_content_x())
@@ -955,9 +958,13 @@ impl Tab {
         {
             terminal_output.handle_pty_bytes(bytes);
             let messages_to_pty = terminal_output.drain_messages_to_pty();
+            let clipboard_update = terminal_output.drain_clipboard_update();
             for message in messages_to_pty {
                 self.write_to_pane_id(message, PaneId::Terminal(pid));
             }
+            if let Some(string) = clipboard_update {
+                self.write_selection_to_clipboard(&string);
+            }
         }
     }
     pub fn write_to_terminals_on_current_tab(&mut self, input_bytes: Vec<u8>) {