From 2161ad13a069ae01748af394684ec4b2e04d0da3 Mon Sep 17 00:00:00 2001
From: robin <comfysagedev@gmail.com>
Date: Sat, 7 Feb 2026 15:38:42 +0100
Subject: [PATCH] feat: add tabline support

---
 lua/lylla/config.lua  | 79 ++++++++++++++++++++++++++++---------------
 lua/lylla/init.lua    |  4 +++
 lua/lylla/tabline.lua | 65 +++++++++++++++++++++++++++++++++++
 3 files changed, 121 insertions(+), 27 deletions(-)
 create mode 100644 lua/lylla/tabline.lua

diff --git a/lua/lylla/config.lua b/lua/lylla/config.lua
index b59b566..a36ac1c 100644
--- a/lua/lylla/config.lua
+++ b/lua/lylla/config.lua
@@ -11,8 +11,9 @@
 ---@field hls table<'normal'|'visual'|'command'|'insert', vim.api.keyset.highlight>
 ---@field modules (lylla.item|lylla.item.tuple|string)[]
 ---@field winbar any[]
+---@field tabline (fun(): (lylla.item|lylla.item.tuple|string)[])|vim.NIL
 
-local M = {}
+local M, H = {}, {}
 
 ---@type lylla.config
 ---@eval return MiniDoc.afterlines_to_code(MiniDoc.current.eval_section)
@@ -75,23 +76,50 @@ M.default = {
     },
   },
   winbar = {},
+  tabline = vim.NIL,
 }
 
 ---@type lylla.config
 ---@diagnostic disable-next-line: missing-fields
 M.config = {}
 
+---@return lylla.config
+function M.get()
+  return H.merge(M.default, M.config)
+end
+
+---@param cfg lylla.config
+---@return lylla.config
+function M.override(cfg)
+  return H.merge(M.default, cfg)
+end
+
+---@param cfg lylla.config
+function M.set(cfg)
+  M.config = cfg
+end
+
+-- helpers ====================================================================
+
+---@param tdefault lylla.config
+---@param toverride lylla.config
+---@return lylla.config
+function H.merge(tdefault, toverride)
+  return H.tmerge(tdefault, toverride)
+end
+
 ---@private
 ---@generic T: table|any[]
 ---@param tdefault T
 ---@param toverride T
 ---@return T
-local function tmerge(tdefault, toverride)
+H.tmerge = function(tdefault, toverride)
   if toverride == nil then
     return tdefault
   end
 
-  if vim.islist(tdefault) then
+  -- do not merge lists
+  if H.islist(tdefault) then
     return toverride
   end
   if vim.tbl_isempty(tdefault) then
@@ -99,12 +127,16 @@ local function tmerge(tdefault, toverride)
   end
 
   return vim.iter(pairs(tdefault)):fold({}, function(tnew, k, v)
-    if toverride[k] == nil or type(v) ~= type(toverride[k]) then
+    if toverride[k] == nil then
       tnew[k] = v
       return tnew
     end
+    if type(v) ~= type(toverride[k]) then
+      tnew[k] = toverride[k]
+      return tnew
+    end
     if type(v) == "table" then
-      tnew[k] = tmerge(v, toverride[k])
+      tnew[k] = H.tmerge(v, toverride[k])
       return tnew
     end
 
@@ -113,31 +145,24 @@ local function tmerge(tdefault, toverride)
   end)
 end
 
----@param tdefault lylla.config
----@param toverride lylla.config
----@return lylla.config
-function M.merge(tdefault, toverride)
-  if vim.fn.has("nvim-0.11.0") == 1 then
-    toverride =
-      vim.tbl_deep_extend("keep", toverride, { editor = { float = { solid_border = vim.o.winborder == "solid" } } })
+---@param t table
+---@return boolean
+H.islist = function(t)
+  if type(t) ~= "table" then
+    return false
   end
-  return tmerge(tdefault, toverride)
-end
 
----@return lylla.config
-function M.get()
-  return M.merge(M.default, M.config)
-end
+  for k, _ in ipairs(t) do
+    return type(k) == "number"
+  end
 
----@param cfg lylla.config
----@return lylla.config
-function M.override(cfg)
-  return M.merge(M.default, cfg)
-end
+  -- non-numeric keys
+  for _, _ in pairs(t) do
+    return false
+  end
 
----@param cfg lylla.config
-function M.set(cfg)
-  M.config = cfg
+  -- empty table
+  return true
 end
 
-return M
+return M, H
diff --git a/lua/lylla/init.lua b/lua/lylla/init.lua
index 9601fca..ed910c0 100644
--- a/lua/lylla/init.lua
+++ b/lua/lylla/init.lua
@@ -80,6 +80,10 @@ function M.init()
     end,
   })
 
+  if config.get().tabline ~= vim.NIL then
+    require("lylla.tabline").setup()
+  end
+
   vim.api.nvim_create_autocmd("ColorSchemePre", {
     group = vim.api.nvim_create_augroup("lylla:resethl", { clear = true }),
     callback = function()
diff --git a/lua/lylla/tabline.lua b/lua/lylla/tabline.lua
new file mode 100644
index 0000000..9f28804
--- /dev/null
+++ b/lua/lylla/tabline.lua
@@ -0,0 +1,65 @@
+vim.g.tablinefn = function()
+  local tabfn = require("lylla.config").get().tabline
+  if tabfn == vim.NIL or type(tabfn) ~= "function" then
+    return
+  end
+
+  local utils = require("lylla.utils")
+
+  return utils.fold(tabfn())
+end
+
+local M, H = {}, {}
+
+M.setup = function()
+  vim.o.tabline = "%!v:lua.vim.g.tablinefn()"
+end
+
+-- helpers ====================================================================
+
+function H.fortabwins(tabn, f)
+  local buflist = vim.fn.tabpagebuflist(tabn)
+
+  return vim
+    .iter(setmetatable({
+      idx = 0,
+    }, {
+      __call = function(t)
+        local i = t.idx + 1
+        if i > vim.fn.tabpagewinnr(tabn, "$") then
+          return
+        end
+        t.idx = i
+        return t.idx
+      end,
+    }))
+    :fold({}, function(t, i)
+      local buf = buflist[i]
+      table.insert(t, { f(i, i == vim.fn.tabpagewinnr(tabn), buf) })
+      return t
+    end)
+end
+
+function H.fortabs(f)
+  return vim
+    .iter(setmetatable({
+      idx = 0,
+    }, {
+      __call = function(t)
+        local i = t.idx + 1
+        if i > vim.fn.tabpagenr("$") then
+          return
+        end
+        t.idx = i
+        return t.idx
+      end,
+    }))
+    :fold({}, function(t, i)
+      table.insert(t, { f(i, i == vim.fn.tabpagenr()) })
+      return t
+    end)
+end
+
+return vim.defaulttable(function(k)
+  return M[k] or H[k]
+end)
-- 
2.51.2