nixvim-config/plugins/cmp.nix

{ ... }:
{
  programs.nixvim = {
    plugins.cmp = {
      enable = true;
      autoEnableSources = true;
      settings = {
        enabled.__raw = ''
          function()
            local filetype = vim.api.nvim_buf_get_option(0, "filetype")
              if filetype == "TelescopePrompt" then
                return false
              end
            return true
          end
        '';

        sources = [
          { name = "nvim_lua"; }
          { name = "nvim_lsp"; }
          { name = "emoji"; }
          {
            name = "buffer"; # text within current buffer
            option.get_bufnrs.__raw = "vim.api.nvim_list_bufs";
            keywordLength = 3;
          }
          # { name = "copilot"; } # enable/disable copilot
          {
            name = "path"; # file system paths
            keywordLength = 3;
          }
          {
            name = "luasnip"; # snippets
            keywordLength = 3;
          }
          { name = "cmdline"; }
        ];

        formatting = {
          fields = [ "kind" "abbr" "menu" ];
          format = ''
            function(entry, vim_item)
              local kind_icons = {
                Text = "󰊄",
                Method = "",
                Function = "󰡱",
                Constructor = "",
                Field = "",
                Variable = "󱀍",
                Class = "",
                Interface = "",
                Module = "󰕳",
                Property = "",
                Unit = "",
                Value = "",
                Enum = "",
                Keyword = "",
                Snippet = "",
                Color = "",
                File = "",
                Reference = "",
                Folder = "",
                EnumMember = "",
                Constant = "",
                Struct = "",
                Event = "",
                Operator = "",
                TypeParameter = "",
              }
              vim_item.kind = string.format("%s", kind_icons[vim_item.kind])
              vim_item.menu = ({
                path = "[Path]",
                nvim_lua = "[NVIM_LUA]",
                nvim_lsp = "[LSP]",
                luasnip = "[Snippet]",
                buffer = "[Buffer]",
              })[entry.source.name]
              return vim_item
            end
          '';
        };

        completion = {
          # completeopt = "menuone,noselect";
          completeopt = "";
        };

        autoEnableSources = true;

        experimental = { ghost_text = true; };

        performance = {
          debounce = 60;
          fetchingTimeout = 200;
          maxViewEntries = 30;
        };

        snippet = {
          expand = ''
            function(args)
              require('luasnip').lsp_expand(args.body)
            end
          '';
        };

        window = {
          completion = { border = "solid"; };
          documentation = { border = "solid"; };
        };

        mapping = {
          "<C-j>" = "cmp.mapping.select_next_item()";
          "<C-n>" = "cmp.mapping.select_next_item()";
          "<C-k>" = "cmp.mapping.select_prev_item()";
          "<C-p>" = "cmp.mapping.select_prev_item()";
          "<C-e>" = "cmp.mapping.abort()";
          "<C-b>" = "cmp.mapping.scroll_docs(-4)";
          "<C-f>" = "cmp.mapping.scroll_docs(4)";
          "<C-c>" = "cmp.mapping.complete()";
          "<Tab>" = "cmp.mapping.confirm({ select = true })";
          # "<Tab>" = ''
          #   cmp.mapping(function(fallback)
          #     -- local context = require("cmp.config.context")
          #     -- local is_comment = context.in_treesitter_capture("comment") == true or context.in_syntax_group("Comment")
          #
          #     local col = vim.fn.col('.') - 1
          #     local line = vim.fn.getline('.')
          #     local char_under_cursor = string.sub(line, col, col)
          #
          #     if col == 0 or string.match(char_under_cursor, '%s') then
          #       fallback()
          #     elseif cmp.visible() then
          #       cmp.confirm({ select = true })
          #     else
          #       fallback()
          #     end
          #   end, { "i", "s" })
          # '';
          "<S-Tab>" = "cmp.mapping.confirm({ behavior = cmp.ConfirmBehavior.Replace, select = true })";
          "<C-l>" = ''
            cmp.mapping(function()
              if luasnip.expand_or_locally_jumpable() then
                luasnip.expand_or_jump()
              end
            end, { 'i', 's' })
          '';
          "<C-h>" = ''
            cmp.mapping(function()
              if luasnip.locally_jumpable(-1) then
                luasnip.jump(-1)
              end
            end, { 'i', 's' })
          '';
        };
      };
    };
  };
}