neovim-flake/modules/plugins/tabline/nvim-bufferline/config.nix

{
  config,
  lib,
  ...
}: let
  inherit (lib.modules) mkIf mkMerge;
  inherit (lib.nvim.binds) mkLuaBinding mkBinding pushDownDefault;
  inherit (lib.nvim.dag) entryAnywhere;

  cfg = config.vim.tabline.nvimBufferline;

  self = import ./nvim-bufferline.nix {inherit lib;};
  inherit (self.options.vim.tabline.nvimBufferline) mappings;
in {
  config = mkIf cfg.enable (
    let
      mouse = {
        right = "'vertical sbuffer %d'";
        close = ''
          function(bufnum)
            require("bufdelete").bufdelete(bufnum, false)
          end
        '';
      };
    in {
      vim = {
        startPlugins = [
          (assert config.vim.visuals.nvimWebDevicons.enable; "nvim-bufferline-lua")
          "bufdelete-nvim"
        ];

        maps.normal = mkMerge [
          (mkLuaBinding cfg.mappings.closeCurrent "require(\"bufdelete\").bufdelete" mappings.closeCurrent.description)
          (mkBinding cfg.mappings.cycleNext ":BufferLineCycleNext<CR>" mappings.cycleNext.description)
          (mkBinding cfg.mappings.cycleNext ":BufferLineCycleNext<CR>" mappings.cycleNext.description)
          (mkBinding cfg.mappings.cyclePrevious ":BufferLineCyclePrev<CR>" mappings.cyclePrevious.description)
          (mkBinding cfg.mappings.pick ":BufferLinePick<CR>" mappings.pick.description)
          (mkBinding cfg.mappings.sortByExtension ":BufferLineSortByExtension<CR>" mappings.sortByExtension.description)
          (mkBinding cfg.mappings.sortByDirectory ":BufferLineSortByDirectory<CR>" mappings.sortByDirectory.description)
          (mkLuaBinding cfg.mappings.sortById "function() require(\"bufferline\").sort_buffers_by(function (buf_a, buf_b) return buf_a.id < buf_b.id end) end" mappings.sortById.description)
          (mkBinding cfg.mappings.moveNext ":BufferLineMoveNext<CR>" mappings.moveNext.description)
          (mkBinding cfg.mappings.movePrevious ":BufferLineMovePrev<CR>" mappings.movePrevious.description)
        ];

        binds.whichKey.register = pushDownDefault {
          "<leader>b" = "+Buffer";
          "<leader>bm" = "BufferLineMove";
          "<leader>bs" = "BufferLineSort";
          "<leader>bsi" = "BufferLineSortById";
        };

        luaConfigRC.nvimBufferline = entryAnywhere ''
          require("bufferline").setup{
             options = {
                mode = "buffers",
                numbers = "both",
                close_command = ${mouse.close},
                right_mouse_command = ${mouse.right},
                indicator = {
                  style = 'icon',
                  indicator_icon = '▎',
                },
                buffer_close_icon = '󰅖',
                modified_icon = '●',
                close_icon = '',
                left_trunc_marker = '',
                right_trunc_marker = '',
                max_name_length = 18,
                max_prefix_length = 15,
                tab_size = 18,
                show_buffer_icons = true,
                show_buffer_close_icons = true,
                show_close_icon = true,
                show_tab_indicators = true,
                persist_buffer_sort = true,
                --separator_style = "thin",
                separator_style = { " ", " " },
                enforce_regular_tabs = true,
                always_show_bufferline = true,
                offsets = {
                  {filetype = "NvimTree", text = "File Explorer", text_align = "center"}
                },
                sort_by = 'extension',
                diagnostics = "nvim_lsp", -- TODO: use coc if it's enabled
                diagnostics_update_in_insert = true,
                diagnostics_indicator = function(count, level, diagnostics_dict, context)
                   local s = ""
                   for e, n in pairs(diagnostics_dict) do
                      local sym = e == "error" and ""
                         or (e == "warning" and "" or "" )
                      if(sym ~= "") then
                      s = s .. " " .. n .. sym
                      end
                   end
                   return s
                end,
                numbers = function(opts)
                  return string.format('%s·%s', opts.raise(opts.id), opts.lower(opts.ordinal))
                end,
             }
          }
        '';
      };
    }
  );
}