fix(panes): show visual error when unable to split panes vertically/horizontally (#2025)

* fix(panes): show visual error when failing to split pane vertically/horizontally

* fix: lockfile

3 files changed, 87 insertions, 4 deletions

diff --git a/zellij-server/src/panes/plugin_pane.rs b/zellij-server/src/panes/plugin_pane.rs
index a530b20b2..3a0ec9c83 100644
--- a/zellij-server/src/panes/plugin_pane.rs
+++ b/zellij-server/src/panes/plugin_pane.rs
@@ -64,6 +64,7 @@ pub(crate) struct PluginPane {
     prev_pane_name: String,
     frame: HashMap<ClientId, PaneFrame>,
     borderless: bool,
+    pane_frame_color_override: Option<(PaletteColor, Option<String>)>,
 }
 
 impl PluginPane {
@@ -102,6 +103,7 @@ impl PluginPane {
             vte_parsers: HashMap::new(),
             grids: HashMap::new(),
             style,
+            pane_frame_color_override: None,
         }
     }
 }
@@ -244,7 +246,13 @@ impl Pane for PluginPane {
         }
         if let Some(grid) = self.grids.get(&client_id) {
             let err_context = || format!("failed to render frame for client {client_id}");
-            let pane_title = if self.pane_name.is_empty()
+            let pane_title = if let Some(text_color_override) = self
+                .pane_frame_color_override
+                .as_ref()
+                .and_then(|(_color, text)| text.as_ref())
+            {
+                text_color_override.into()
+            } else if self.pane_name.is_empty()
                 && input_mode == InputMode::RenamePane
                 && frame_params.is_main_client
             {
@@ -257,12 +265,15 @@ impl Pane for PluginPane {
                 self.pane_name.clone()
             };
 
-            let frame = PaneFrame::new(
+            let mut frame = PaneFrame::new(
                 self.current_geom().into(),
                 grid.scrollback_position_and_length(),
                 pane_title,
                 frame_params,
             );
+            if let Some((frame_color_override, _text)) = self.pane_frame_color_override.as_ref() {
+                frame.override_color(*frame_color_override);
+            }
 
             let res = match self.frame.get(&client_id) {
                 // TODO: use and_then or something?
@@ -469,6 +480,17 @@ impl Pane for PluginPane {
             )]))
             .unwrap();
     }
+    fn add_red_pane_frame_color_override(&mut self, error_text: Option<String>) {
+        self.pane_frame_color_override = Some((self.style.colors.red, error_text));
+    }
+    fn clear_pane_frame_color_override(&mut self) {
+        self.pane_frame_color_override = None;
+    }
+    fn frame_color_override(&self) -> Option<PaletteColor> {
+        self.pane_frame_color_override
+            .as_ref()
+            .map(|(color, _text)| *color)
+    }
 }
 
 impl PluginPane {
diff --git a/zellij-server/src/panes/terminal_pane.rs b/zellij-server/src/panes/terminal_pane.rs
index b5c51c659..4d5ed840c 100644
--- a/zellij-server/src/panes/terminal_pane.rs
+++ b/zellij-server/src/panes/terminal_pane.rs
@@ -109,7 +109,8 @@ pub struct TerminalPane {
     is_held: Option<(Option<i32>, IsFirstRun, RunCommand)>, // a "held" pane means that its command has either exited and the pane is waiting for a
     // possible user instruction to be re-run, or that the command has not yet been run
     banner: Option<String>, // a banner to be rendered inside this TerminalPane, used for panes
-                            // held on startup and can possibly be used to display some errors
+    // held on startup and can possibly be used to display some errors
+    pane_frame_color_override: Option<(PaletteColor, Option<String>)>,
 }
 
 impl Pane for TerminalPane {
@@ -301,7 +302,13 @@ impl Pane for TerminalPane {
     ) -> Result<Option<(Vec<CharacterChunk>, Option<String>)>> {
         let err_context = || format!("failed to render frame for client {client_id}");
         // TODO: remove the cursor stuff from here
-        let pane_title = if self.pane_name.is_empty()
+        let pane_title = if let Some(text_color_override) = self
+            .pane_frame_color_override
+            .as_ref()
+            .and_then(|(_color, text)| text.as_ref())
+        {
+            text_color_override.into()
+        } else if self.pane_name.is_empty()
             && input_mode == InputMode::RenamePane
             && frame_params.is_main_client
         {
@@ -353,6 +360,9 @@ impl Pane for TerminalPane {
                 frame.add_exit_status(exit_status.as_ref().copied());
             }
         }
+        if let Some((frame_color_override, _text)) = self.pane_frame_color_override.as_ref() {
+            frame.override_color(*frame_color_override);
+        }
 
         let res = match self.frame.get(&client_id) {
             // TODO: use and_then or something?
@@ -669,6 +679,17 @@ impl Pane for TerminalPane {
         }
         self.set_should_render(true);
     }
+    fn add_red_pane_frame_color_override(&mut self, error_text: Option<String>) {
+        self.pane_frame_color_override = Some((self.style.colors.red, error_text));
+    }
+    fn clear_pane_frame_color_override(&mut self) {
+        self.pane_frame_color_override = None;
+    }
+    fn frame_color_override(&self) -> Option<PaletteColor> {
+        self.pane_frame_color_override
+            .as_ref()
+            .map(|(color, _text)| *color)
+    }
 }
 
 impl TerminalPane {
@@ -717,6 +738,7 @@ impl TerminalPane {
             search_term: String::new(),
             is_held: None,
             banner: None,
+            pane_frame_color_override: None,
         }
     }
     pub fn get_x(&self) -> usize {
diff --git a/zellij-server/src/panes/tiled_panes/mod.rs b/zellij-server/src/panes/tiled_panes/mod.rs
index b5caa5916..ee752ea15 100644
--- a/zellij-server/src/panes/tiled_panes/mod.rs
+++ b/zellij-server/src/panes/tiled_panes/mod.rs
@@ -205,6 +205,19 @@ impl TiledPanes {
             })
             .collect()
     }
+    pub fn borderless_pane_geoms(&self) -> Vec<Viewport> {
+        self.panes
+            .values()
+            .filter_map(|p| {
+                let geom = p.position_and_size();
+                if p.borderless() {
+                    Some(geom.into())
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
     pub fn first_selectable_pane_id(&self) -> Option<PaneId> {
         self.panes
             .iter()
@@ -295,6 +308,19 @@ impl TiledPanes {
         }
         false
     }
+    pub fn can_split_active_pane_horizontally(&self, client_id: ClientId) -> bool {
+        let active_pane_id = &self.active_panes.get(&client_id).unwrap();
+        let active_pane = self.panes.get(active_pane_id).unwrap();
+        let full_pane_size = active_pane.position_and_size();
+        if full_pane_size.rows.is_fixed() {
+            return false;
+        }
+        if split(SplitDirection::Horizontal, &full_pane_size).is_some() {
+            true
+        } else {
+            false
+        }
+    }
     pub fn split_pane_horizontally(
         &mut self,
         pid: PaneId,
@@ -313,6 +339,19 @@ impl TiledPanes {
             self.relayout(SplitDirection::Vertical);
         }
     }
+    pub fn can_split_active_pane_vertically(&self, client_id: ClientId) -> bool {
+        let active_pane_id = &self.active_panes.get(&client_id).unwrap();
+        let active_pane = self.panes.get(active_pane_id).unwrap();
+        let full_pane_size = active_pane.position_and_size();
+        if full_pane_size.cols.is_fixed() {
+            return false;
+        }
+        if split(SplitDirection::Vertical, &full_pane_size).is_some() {
+            true
+        } else {
+            false
+        }
+    }
     pub fn split_pane_vertically(
         &mut self,
         pid: PaneId,