{ helpers, ... }:
let
  inherit (helpers) mkRaw;
in
{
  plugins.luasnip = {
    enable = true;
    filetypeExtend = {
      lua = [
        "c"
        "cpp"
      ];
    };
    settings = {
      # https://github.com/L3MON4D3/LuaSnip/blob/master/DOC.md#config-options
      enable_autosnippets = true;
      # https://github.com/L3MON4D3/LuaSnip/blob/master/DOC.md#variables
      cut_selection_keys = "<Tab>";
      update_events = "TextChanged,TextChangedI";
    };
    # https://github.com/L3MON4D3/LuaSnip/blob/master/DOC.md#lua
    fromLua = [
      { paths = ./snippets; } # snippts attached to nixvim repo
      { paths = "~/snippets"; } # snippts in home dir
    ];
  };
  extraFiles = {
    "lua/luasnip-helper-funcs.lua".source = ./helpers/luasnip-helper-funcs.lua;
  };
  # https://github.com/L3MON4D3/LuaSnip/wiki/Nice-Configs#hint-node-type-with-virtual-text
  extraConfigLua = ''
    local types = require("luasnip.util.types")
    require'luasnip'.config.setup({
      ext_opts = {
        [types.choiceNode] = {
          active = {
            -- virt_text = {{"●", "GruvboxOrange"}}
            -- see ":h group-name" (syntax highlighting)
            virt_text = {{ '««« Choice Node', 'Constant', }}
          }
        },
        [types.insertNode] = {
          active = {
            -- virt_text = {{"●", "GruvboxBlue"}}
            -- see ":h group-name" (syntax highlighting)
            virt_text = {{ '««« Insert Node', 'Comment', }}
          }
        }
      },
    })
  '';
  keymaps = [
    {
      mode = [
        "i"
        "s"
      ];
      key = "<C-j>";
      action = mkRaw ''
        function()
          local ls = require('luasnip')
          if ls.expand_or_jumpable() then
            ls.expand_or_jump()
          end
        end
      '';
      options.silent = true;
    }
    {
      mode = [
        "i"
        "s"
      ];
      key = "<C-k>";
      action = mkRaw ''
        function()
          local ls = require('luasnip')
          if ls.jumpable(-1) then
            ls.jump(-1)
          end
        end
      '';
      options.silent = true;
    }
    {
      mode = [
        "i"
        "s"
      ];
      key = "<C-e>";
      action = mkRaw ''
        function()
          local ls = require('luasnip')
          if ls.choice_active() then
            ls.change_choice(1)
          end
        end
      '';
      options.silent = true;
    }
  ];
}