From 66f009b873f693ba3f2e2169065b161fc2045a9e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nikodem=20Rabuli=C5=84ski?= <nikodem@rabulinski.com>
Date: Sat, 1 Jul 2023 14:53:54 +0200
Subject: [PATCH] Add style configuration for tabline, make tabline compatible
 with bufferline

---
 helix-term/src/ui/editor.rs | 40 ++++++++++++++++++++++++++++---------
 helix-view/src/editor.rs    | 14 +++++++++++++
 helix-view/src/tabs.rs      | 10 ++++++++++
 3 files changed, 55 insertions(+), 9 deletions(-)

diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
index cf9a35df9..5e8ee22eb 100644
--- a/helix-term/src/ui/editor.rs
+++ b/helix-term/src/ui/editor.rs
@@ -583,18 +583,21 @@ impl EditorView {
             viewport,
             editor
                 .theme
-                .try_get("ui.bufferline.background")
+                .try_get("ui.tabline.background")
+                .or_else(|| editor.theme.try_get("ui.bufferline.background"))
                 .unwrap_or_else(|| editor.theme.get("ui.statusline")),
         );
 
-        let bufferline_active = editor
+        let tabline_active = editor
             .theme
-            .try_get("ui.bufferline.active")
+            .try_get("ui.tabline.active")
+            .or_else(|| editor.theme.try_get("ui.bufferline.active"))
             .unwrap_or_else(|| editor.theme.get("ui.statusline.active"));
 
-        let bufferline_inactive = editor
+        let tabline_inactive = editor
             .theme
-            .try_get("ui.bufferline")
+            .try_get("ui.tabline")
+            .or_else(|| editor.theme.try_get("ui.bufferline"))
             .unwrap_or_else(|| editor.theme.get("ui.statusline.inactive"));
 
         let mut x = viewport.x;
@@ -602,9 +605,9 @@ impl EditorView {
         let current_tab = editor.tabs.focus;
         for (id, tab) in editor.tabs.iter_tabs() {
             let style = if current_tab == id {
-                bufferline_active
+                tabline_active
             } else {
-                bufferline_inactive
+                tabline_inactive
             };
 
             let text = format!(" {} ", tab.name);
@@ -1511,6 +1514,14 @@ impl Component for EditorView {
         surface.set_style(area, cx.editor.theme.get("ui.background"));
         let config = cx.editor.config();
 
+        // check if tabline should be rendered
+        use helix_view::editor::TabLine;
+        let use_tabline = if let TabLine::Multiple = config.tabline {
+            cx.editor.tabs.len() > 1
+        } else {
+            true
+        };
+
         // check if bufferline should be rendered
         use helix_view::editor::BufferLine;
         let use_bufferline = match config.bufferline {
@@ -1519,8 +1530,15 @@ impl Component for EditorView {
             _ => false,
         };
 
-        // -1 for commandline and -1 for bufferline
+        // -1 for commandline and -1 for tabline
+        let mut bufferline_area = area;
         let mut editor_area = area.clip_bottom(1);
+        if use_tabline {
+            editor_area = editor_area.clip_top(1);
+            bufferline_area = bufferline_area.clip_top(1);
+        }
+
+        // -1 for bufferline
         if use_bufferline {
             editor_area = editor_area.clip_top(1);
         }
@@ -1528,10 +1546,14 @@ impl Component for EditorView {
         // if the terminal size suddenly changed, we need to trigger a resize
         cx.editor.resize(editor_area);
 
-        if use_bufferline {
+        if use_tabline {
             Self::render_tabline(cx.editor, area.with_height(1), surface);
         }
 
+        if use_bufferline {
+            Self::render_bufferline(cx.editor, bufferline_area.with_height(1), surface);
+        }
+
         for (view, is_focused) in cx.editor.tabs.curr_tree().views() {
             let doc = cx.editor.document(view.doc).unwrap();
             self.render_view(cx.editor, doc, view, area, surface, is_focused);
diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index 2023dbede..7a4f058d5 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -311,6 +311,8 @@ pub struct Config {
     pub rulers: Vec<u16>,
     #[serde(default)]
     pub whitespace: WhitespaceConfig,
+    /// Display open tabs along the top
+    pub tabline: TabLine,
     /// Persistently display open buffers along the top
     pub bufferline: BufferLine,
     /// Vertical indent width guides.
@@ -625,6 +627,17 @@ impl Default for CursorShapeConfig {
     }
 }
 
+/// tabline render modes
+#[derive(Debug, Default, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "kebab-case")]
+pub enum TabLine {
+    /// Always render
+    Always,
+    /// Only if multiple tabs are open
+    #[default]
+    Multiple,
+}
+
 /// bufferline render modes
 #[derive(Debug, Default, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case")]
@@ -898,6 +911,7 @@ impl Default for Config {
             terminal: get_terminal_provider(),
             rulers: Vec::new(),
             whitespace: WhitespaceConfig::default(),
+            tabline: TabLine::default(),
             bufferline: BufferLine::default(),
             indent_guides: IndentGuidesConfig::default(),
             color_modes: false,
diff --git a/helix-view/src/tabs.rs b/helix-view/src/tabs.rs
index a33dad415..25aa22081 100644
--- a/helix-view/src/tabs.rs
+++ b/helix-view/src/tabs.rs
@@ -76,4 +76,14 @@ impl Tabs {
         self.focus = id;
         id
     }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.tabs.len()
+    }
+
+    #[inline]
+    pub fn is_empty(&self) -> bool {
+        self.tabs.is_empty()
+    }
 }