nvim/lua/config/lualine.lua

local fn = vim.fn

local function get_coc_lsp_client()
  local clients = vim.g.coc_service_initialized and vim.fn['CocAction']('services') or {}
  for _, client in pairs(clients) do
    if client['state'] == 'running' then
      local client_name = client['id']
      -- Remove 'languageserver.' prefix if it exists
      client_name = client_name:gsub('^languageserver%.', '')
      return client_name
    end
  end
  return ''
end

local function spell()
    if vim.o.spell then
        return string.format("[SPELL]")
    end

    return ""
end

--- show indicator for Chinese IME
local function ime_state()
    if vim.g.is_mac then
        local layout = fn.libcall(vim.g.XkbSwitchLib, "Xkb_Switch_getXkbLayout", "")
        local res = fn.match(layout, [[\v(Squirrel\.Rime|SCIM.ITABC)]])
        if res ~= -1 then
            return "[CN]"
        end
    end

    return ""
end

local diff = function()
    local git_status = vim.b.gitsigns_status_dict
    if git_status == nil then
        return
    end

    local modify_num = git_status.changed
    local remove_num = git_status.removed
    local add_num = git_status.added

    local info = { added = add_num, modified = modify_num, removed = remove_num }
    -- vim.print(info)
    return info
end

local virtual_env = function()
    -- only show virtual env for Python
    if vim.bo.filetype ~= "python" then
        return ""
    end

    local conda_env = os.getenv("CONDA_DEFAULT_ENV")
    local venv_path = os.getenv("VIRTUAL_ENV")

    if venv_path == nil then
        if conda_env == nil then
            return ""
        else
            return string.format("  %s (conda)", conda_env)
        end
    else
        local venv_name = vim.fn.fnamemodify(venv_path, ":t")
        return string.format("  %s (venv)", venv_name)
    end
end

require("lualine").setup {
    options = {
        icons_enabled = true,
        theme = "auto",
        globalstatus = true,
        component_separators = '',
        section_separators = { left = '', right = '' },
        disabled_filetypes = {},
        always_divide_middle = true,
    },
    sections = {
        lualine_a = {
            {
                "mode",
            },
        },
        lualine_b = {
            {
                "branch",
                fmt = function(name, _)
                    -- truncate branch name in case the name is too long
                    return string.sub(name, 1, 20)
                end,
                color = { gui = "italic,bold" },
                separator = { right = "" },
            },
            {
                virtual_env,
                color = { fg = "black", bg = "#F1CA81" },
            },
        },
        lualine_c = {
            {
                "filename",
                symbols = {
                    readonly = "[🔒]",
                },
            },
            {
                "diff",
                source = diff,
            },
            {
                "%S",
                color = { gui = "bold", fg = "cyan" },
            },
            {
                spell,
                color = { fg = "black", bg = "#a7c080" },
            },
        },
        lualine_x = {
            {
                ime_state,
                color = { fg = "black", bg = "#f46868" },
            },
            {
                get_coc_lsp_client,
                icon = " LSP:",
            },
            {
                "diagnostics",
                sources = { "nvim_diagnostic" },
                symbols = { error = "🆇 ", warn = "⚠️ ", info = "ℹ️ ", hint = " " },
            },
        },
        lualine_y = {
            { "encoding", fmt = string.upper },
            {
                "fileformat",
                symbols = {
                    unix = "",
                    dos = "",
                    mac = "",
                },
            },
            "filetype",
        },
        lualine_z = {
            "progress",
        },
    },
    inactive_sections = {
        lualine_a = {},
        lualine_b = {},
        lualine_c = { "filename" },
        lualine_x = { "location" },
        lualine_y = {},
        lualine_z = {},
    },
    tabline = {},
    extensions = { "quickfix", "fugitive", "nvim-tree" },
}