pojokcodeid.nvim-lazy/lua/user/bufferline.lua

local status_ok, bufferline = pcall(require, "bufferline")
if not status_ok then
	return
end

local icons = require("user.icons")
local use_icons = true

local function diagnostics_indicator(num, _, diagnostics, _)
	local result = {}
	local symbols = {
		error = icons.diagnostics.Error,
		warning = icons.diagnostics.Warning,
		info = icons.diagnostics.Information,
	}
	if not use_icons then
		return "(" .. num .. ")"
	end
	for name, count in pairs(diagnostics) do
		if symbols[name] and count > 0 then
			table.insert(result, symbols[name] .. " " .. count)
		end
	end
	result = table.concat(result, " ")
	return #result > 0 and result or ""
end

bufferline.setup({
	options = {
		color_icons = true,
		numbers = "none", -- | "ordinal" | "buffer_id" | "both" | function({ ordinal, id, lower, raise }): string,
		--close_command = "Bdelete! %d", -- can be a string | function, see "Mouse actions"
		close_command = function(bufnum)
			require("bufdelete").bufdelete(bufnum, true)
		end,
		--right_mouse_command = "Bdelete! %d", -- can be a string | function, see "Mouse actions"
		right_mouse_command = function(bufnum)
			require("bufdelete").bufdelete(bufnum, true)
		end,
		left_mouse_command = "buffer %d", -- can be a string | function, see "Mouse actions"
		middle_mouse_command = nil, -- can be a string | function, see "Mouse actions"
		-- NOTE: this plugin is designed with this icon in mind,
		-- and so changing this is NOT recommended, this is intended
		-- as an escape hatch for people who cannot bear it for whatever reason
		indicator_icon = nil,
		indicator = { style = "icon", icon = "▎" },
		--buffer_close_icon = "",
		buffer_close_icon = icons.ui.Close,
		-- buffer_close_icon = '',
		-- modified_icon = "●",
		modified_icon = icons.ui.Circle,
		-- close_icon = "",
		close_icon = icons.ui.BoldClose,
		-- close_icon = '',
		--left_trunc_marker = "",
		left_trunc_marker = icons.ui.ArrowCircleLeft,
		--right_trunc_marker = "",
		right_trunc_marker = icons.ui.ArrowCircleRight,
		--- name_formatter can be used to change the buffer's label in the bufferline.
		--- Please note some names can/will break the
		--- bufferline so use this at your discretion knowing that it has
		--- some limitations that will *NOT* be fixed.
		-- name_formatter = function(buf)  -- buf contains a "name", "path" and "bufnr"
		--   -- remove extension from markdown files for example
		--   if buf.name:match('%.md') then
		--     return vim.fn.fnamemodify(buf.name, ':t:r')
		--   end
		-- end,
		max_name_length = 30,
		max_prefix_length = 30, -- prefix used when a buffer is de-duplicated
		tab_size = 21,
		diagnostics = false, -- | "nvim_lsp" | "coc",
		diagnostics_update_in_insert = false,
		diagnostics_indicator = diagnostics_indicator,
		-- diagnostics_indicator = function(count, level, diagnostics_dict, context)
		--   return "("..count..")"
		-- end,
		-- NOTE: this will be called a lot so don't do any heavy processing here
		-- custom_filter = function(buf_number)
		--   -- filter out filetypes you don't want to see
		--   if vim.bo[buf_number].filetype ~= "<i-dont-want-to-see-this>" then
		--     return true
		--   end
		--   -- filter out by buffer name
		--   if vim.fn.bufname(buf_number) ~= "<buffer-name-I-dont-want>" then
		--     return true
		--   end
		--   -- filter out based on arbitrary rules
		--   -- e.g. filter out vim wiki buffer from tabline in your work repo
		--   if vim.fn.getcwd() == "<work-repo>" and vim.bo[buf_number].filetype ~= "wiki" then
		--     return true
		--   end
		-- end,
		offsets = {
			{
				filetype = "NvimTree",
				text = "Explorer",
				highlight = "Directory",
				text_align = "left",
				padding = 1,
			},
			{
				filetype = "neo-tree",
				text = "Explorer",
				highlight = "Directory",
				text_align = "left",
				padding = 1,
			},
		},
		show_buffer_icons = true,
		show_buffer_close_icons = true,
		show_close_icon = true,
		show_tab_indicators = true,
		persist_buffer_sort = true, -- whether or not custom sorted buffers should persist
		-- can also be a table containing 2 custom separators
		-- [focused and unfocused]. eg: { '|', '|' }
		separator_style = "thin", -- | "thick" | "thin" | { 'any', 'any' },
		enforce_regular_tabs = true,
		always_show_bufferline = true,
		-- sort_by = 'id' | 'extension' | 'relative_directory' | 'directory' | 'tabs' | function(buffer_a, buffer_b)
		--   -- add custom logic
		--   return buffer_a.modified > buffer_b.modified
		-- end
	},
	highlights = {
		fill = {
			fg = { attribute = "fg", highlight = "#ff0000" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},
		background = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},

		-- buffer_selected = {
		--   fg = {attribute='fg',highlight='#ff0000'},
		--   bg = {attribute='bg',highlight='#0000ff'},
		--   gui = 'none'
		--   },
		buffer_visible = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},

		close_button = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},
		close_button_visible = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},
		-- close_button_selected = {
		--   fg = {attribute='fg',highlight='TabLineSel'},
		--   bg ={attribute='bg',highlight='TabLineSel'}
		--   },

		tab_selected = {
			fg = { attribute = "fg", highlight = "Normal" },
			bg = { attribute = "bg", highlight = "Normal" },
		},
		tab = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},
		tab_close = {
			-- fg = {attribute='fg',highlight='LspDiagnosticsDefaultError'},
			fg = { attribute = "fg", highlight = "TabLineSel" },
			bg = { attribute = "bg", highlight = "Normal" },
		},

		duplicate_selected = {
			fg = { attribute = "fg", highlight = "TabLineSel" },
			bg = { attribute = "bg", highlight = "TabLineSel" },
			underline = true,
		},
		duplicate_visible = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
			underline = true,
		},
		duplicate = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
			underline = true,
		},

		modified = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},
		modified_selected = {
			fg = { attribute = "fg", highlight = "Normal" },
			bg = { attribute = "bg", highlight = "Normal" },
		},
		modified_visible = {
			fg = { attribute = "fg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},

		separator = {
			fg = { attribute = "bg", highlight = "TabLine" },
			bg = { attribute = "bg", highlight = "TabLine" },
		},
		separator_selected = {
			fg = { attribute = "bg", highlight = "Normal" },
			bg = { attribute = "bg", highlight = "Normal" },
		},
		-- separator_visible = {
		--   fg = {attribute='bg',highlight='TabLine'},
		--   bg = {attribute='bg',highlight='TabLine'}
		--   },
		indicator_selected = {
			fg = { attribute = "fg", highlight = "LspDiagnosticsDefaultHint" },
			bg = { attribute = "bg", highlight = "Normal" },
		},
	},
})