{ pkgs, config, ... }:
let vim_conf = ''
  " if tabular
  vmap a= :Tabularize /=<CR>
  vmap a; :Tabularize /::<CR>
  vmap a- :Tabularize /-><CR>

  colorscheme delek

  filetype plugin indent on
  set title
  set nocompatible
  set smartcase
  set shiftwidth=2 tabstop=2 expandtab
  set number
  set path=$PWD/**
  set completeopt=menu,longest
  set wildmode=list:full wildignore+=${builtins.concatStringsSep "," config.constants.ignore}
  set shortmess+=aI
  set nowritebackup noswapfile
  set mouse=a
  set showmatch
  set encoding=utf8 ffs=unix,dos,mac
  set smartindent
  set nowrap
  set nohlsearch
  set clipboard=unnamedplus
  set nopaste
  set list listchars=tab:⇥\ ,extends:❯,precedes:❮,nbsp:␣,trail:· showbreak=↪
  set foldlevelstart=30

  if exists("g:loaded_netrwPlugin")
    let g:netrw_banner=0
    let g:netrw_browse_split=4
    let g:netrw_altv=1 " open splits to the right
    let g:netrw_liststyle=3 " tree view
    let g:netrw_list_hide=netrw_gitignore#Hide()
    let g:netrw_list_hide.=',\(^\|\s\s\)\zs\.\S\+'
  endif

  call matchadd('colorcolumn', '\%101v', 100)
  highlight colorcolumn ctermbg=red

  " undofile - This allows you to use undos after exiting and restarting
  " This, like swap and backups, uses .vim-undo first, then ~/.vim/undo
  " :help undo-persistence
  if exists("+undofile")
    if isdirectory($HOME . '/.vim/undo') == 0
      :silent !mkdir -p ~/.vim/undo > /dev/null 2>&1
    endif
    set undodir=./.vim-undo//
    set undodir+=~/.vim/undo//
    set undofile
  endif

  nmap <C-j> ddp | vmap <C-j> xp`[V`]
  nmap <C-k> ddkP | vmap <C-k> xkP`[V`]

  nnoremap <silent> <Space> @=(foldlevel('.')?'za':"\<Space>")<CR>
  vnoremap <Space> zf

  command! RandomLine execute 'normal! '.(system('/bin/sh -c "echo -n $RANDOM"') % line('$')).'G'

  function! <SID>StripTrailingWhitespaces()
    let _s=@/
    let l=line(".")
    let c=col(".")

    %s/\s\+$//e

    let @/=_s
    call cursor(l,c)
  endfunction

  function! s:DiffWithSaved()
    let filetype=&ft
    diffthis
    vnew | r # | normal! 1Gdd
    diffthis
    execute "setlocal bt=nofile bh=wipe nobl noswf ro ft=" . filetype
  endfunction
  command! DiffSaved call s:DiffWithSaved()

  if has("autocmd")
    autocmd bufnewfile,bufread *.4th set filetype=forth
    autocmd bufnewfile,bufread *.asm set filetype=nasm
    autocmd bufnewfile,bufread *.c set keywordprg=man\ 3
    autocmd bufnewfile,bufread *.conf set filetype=conf
    autocmd bufnewfile,bufread *.fs :packadd vim-fsharp | set filetype=fsharp
    autocmd bufnewfile,bufread *.h set keywordprg=man\ 3
    autocmd bufnewfile,bufread *.md set filetype=markdown.pandoc | set nospell
    autocmd bufnewfile,bufread *.nix :packadd vim-nix | set filetype=nix
    autocmd bufnewfile,bufread *.rust :packadd rust-vim deoplete-rust
    autocmd bufnewfile,bufread *.tex :packadd vimtex | set filetype=tex
    autocmd bufnewfile,bufread *.ts :packadd vim-typescript
    autocmd bufnewfile,bufread *.journal :packadd vim-ledger | set filetype=ledger shiftwidth=4
    autocmd bufnewfile,bufread config set filetype=conf
    autocmd bufnewfile,bufread *.elm :packadd elm-vim | set filetype=elm shiftwidth=4
    autocmd filetype haskell set formatprg=hindent
    autocmd filetype python set formatprg=black
    autocmd filetype javascript *.js :packadd vim-javascript
    autocmd filetype make setlocal noexpandtab
    autocmd filetype markdown,text set formatoptions+=t
    autocmd filetype markdown,text set formatprg=par\ -w80
    autocmd filetype markdown,text set textwidth=80
    autocmd bufreadpost *
      \ if line("'\"") > 0 && line("'\"") <= line("$") |
        \ exe "normal! g`\"" |
      \ endif
    autocmd bufreadpre * setlocal foldmethod=indent
    autocmd bufwritepre * :call <SID>StripTrailingWhitespaces()
    autocmd bufwinenter * if &fdm == 'indent' | setlocal foldmethod=manual | endif
  endif

  if exists("g:loaded_startify")
    let g:startify_custom_header = \'\'
  endif

  "if exists("g:loaded_airline")
    set noshowmode laststatus=0 noruler
    let g:airline#extensions#tabline#close_symbol = 'X'
    let g:airline#extensions#tabline#enabled = 0
    "let g:airline#extensions#tabline#left_alt_sep = ''
    "let g:airline#extensions#tabline#left_sep = ''
    "let g:airline#extensions#tabline#right_alt_sep = ''
    "let g:airline#extensions#tabline#right_sep = ''
    let g:airline#extensions#tabline#show_close_button = 1
    let g:airline#extensions#tabline#show_tab_type = 0
    let g:airline#extensions#tabline#tab_min_count = 2
    let g:airline#extensions#tabline#tab_nr_type = 0
    let g:airline#extensions#tmuxline#enabled = 0
    "let g:airline#extensions#wordcount#enabled = 1
    "let g:airline_left_alt_sep = ''
    "let g:airline_left_sep = ''
    "let g:airline_right_alt_sep = ''
    "let g:airline_right_sep = ''
    let g:airline_section_z = '%{line(".")}/%{line("$")} %{col(".")}'
  "endif
  "if exists("g:loaded_airline_themes")
    let g:airline_theme='base16'
  "endif
'';
in {
  environment.variables.EDITOR = pkgs.lib.mkForce "nvim";
  environment.shellAliases.vi = "nvim";
  environment.shellAliases.view = "nvim -R";

  programs.nano.nanorc = ''
    set autoindent
    set boldtext
    set morespace
    set smarthome
    set tabsize 4
    set tabstospaces
  '';

  nixpkgs.config.packageOverrides = pkgs: {
    nvim = pkgs.neovim.override {
      configure = {
        customRC = vim_conf;
        packages.nvim = with pkgs.vimPlugins; {
          start = [
            ctrlp
            deoplete-nvim
            supertab
            syntastic
            tabular
            vim-airline vim-airline-themes
            vim-commentary
            vim-eunuch
            vim-fugitive
            vim-gitgutter
            vim-pandoc vim-pandoc-after vim-pandoc-syntax
            vim-repeat
            vim-sensible
            vim-startify
            vim-surround
          ];
          opt = [
            elm-vim
            deoplete-rust
            idris-vim
            vimtex
            rust-vim
            typescript-vim
            vim-javascript
            vim-nix
            (pkgs.vimUtils.buildVimPluginFrom2Nix {
              name = "vim-ledger";
              src = pkgs.fetchFromGitHub {
                owner = "ledger";
                repo = "vim-ledger";
                rev = "6eb3bb21aa979cc295d0480b2179938c12b33d0d";
                sha256 = "0rbwyaanvl2bqk8xm4kq8fkv8y92lpf9xx5n8gw54iij7xxhnj01";
              };
            })
            (pkgs.vimUtils.buildVimPluginFrom2Nix {
              name = "vim-fsharp";
              src = pkgs.fetchFromGitHub {
                owner = "fsharp";
                repo = "vim-fsharp";
                rev = "627db7d701747e8fd7924b6505c61e16a369fb72";
                sha256 = "00hhgn2p54faysx1ddccyhl9jnvddgxsczhv0np3mgzza6ls4838";
              };
            })
          ];
        };
      };
    };
  };

  environment.systemPackages = [pkgs.nvim];
}