nixos-config/config/programs/vim.nix

{ pkgs, ... }:
let dsquotes = "''"; in
{
  programs.neovim = {
    enable = true;
    coc = {
      enable = true;
      settings = {
        languageserver = {
          nix = {
            command = "${pkgs.rnix-lsp}/bin/rnix-lsp";
            filetypes = [
              "nix"
            ];
          };
        };
      };
    };
    extraConfig = ''
      set tabstop=4
      set shiftwidth=4
      set expandtab
      set nocompatible
      set number relativenumber
      set mouse=a
      set hidden
      set clipboard=unnamedplus " the *correct* default clipboard thank you
      " Give more space for displaying messages.
      set cmdheight=2
      " Having longer updatetime (default is 4000 ms = 4 s) leads to noticeable
      " delays and poor user experience.
      set updatetime=300
      " Don't pass messages to |ins-completion-menu|.
      set shortmess+=c
      set signcolumn=number


      " NerdTree config
      " Automatically open NERDTree and move to the previous window
      autocmd VimEnter * NERDTree | wincmd p
      " Close vim when NERDTree is the only window left
      autocmd BufEnter * if winnr('$') == 1 && exists('b:NERDTree') && b:NERDTree.isTabTree() | quit | endif
      " Ban replacing NERDTree
      autocmd BufEnter * if bufname('#') =~ 'NERD_tree_\d\+' && bufname('%') !~ 'NERD_tree_\d\+' && winnr('$') > 1 |
              \ let buf=bufnr() | buffer# | execute "normal! \<C-W>w" | execute 'buffer'.buf | endif
      
      " NerdTree git plugin
      " Use nerdfonts
      let g:NERDTreeGitStatusUseNerdFonts = 1
      
      " CtrlP config
      let g:ctrlp_map = '<c-p>'
      let g:ctrlp_cmd = 'CtrlP'

      " Tagbar config
      nmap <F8> :TagbarToggle<CR>

      " CoC Config
      " Use tab for trigger completion with characters ahead and navigate.
      " NOTE: Use command ':verbose imap <tab>' to make sure tab is not mapped by
      " other plugin before putting this into your config.
      inoremap <silent><expr> <TAB>
               \ pumvisible() ? "\<C-n>" :
               \ <SID>check_back_space() ? "\<TAB>" :
               \ coc#refresh()
      inoremap <expr><S-TAB> pumvisible() ? "\<C-p>" : "\<C-h>"

      function! s:check_back_space() abort
        let col = col('.') - 1
        return !col || getline('.')[col - 1]  =~# '\s'
      endfunction
      inoremap <silent><expr> <c-space> coc#refresh()
      " Make <CR> auto-select the first completion item and notify coc.nvim to
      " format on enter, <cr> could be remapped by other vim plugin
      inoremap <silent><expr> <cr> pumvisible() ? coc#_select_confirm()
                                   \: "\<C-g>u\<CR>\<c-r>=coc#on_enter()\<CR>"
      
      " Use `[g` and `]g` to navigate diagnostics
      " Use `:CocDiagnostics` to get all diagnostics of current buffer in location list.
      nmap <silent> [g <Plug>(coc-diagnostic-prev)
      nmap <silent> ]g <Plug>(coc-diagnostic-next)

      " GoTo code navigation.
      nmap <silent> gd <Plug>(coc-definition)
      nmap <silent> gy <Plug>(coc-type-definition)
      nmap <silent> gi <Plug>(coc-implementation)
      nmap <silent> gr <Plug>(coc-references)

      " Use K to show documentation in preview window.
      nnoremap <silent> K :call <SID>show_documentation()<CR>

      function! s:show_documentation()
        if (index(['vim','help'], &filetype) >= 0)
          execute 'h '.expand('<cword>')
        elseif (coc#rpc#ready())
          call CocActionAsync('doHover')
        else
          execute '!' . &keywordprg . " " . expand('<cword>')
        endif
      endfunction

      " Highlight the symbol and its references when holding the cursor.
      autocmd CursorHold * silent call CocActionAsync('highlight')

      " Symbol renaming.
      nmap <leader>rn <Plug>(coc-rename)

      " Formatting selected code.
      xmap <leader>f  <Plug>(coc-format-selected)
      nmap <leader>f  <Plug>(coc-format-selected)

      augroup mygroup
        autocmd!
        " Setup formatexpr specified filetype(s).
        autocmd FileType typescript,json setl formatexpr=CocAction('formatSelected')
        " Update signature help on jump placeholder.
        autocmd User CocJumpPlaceholder call CocActionAsync('showSignatureHelp')
      augroup end

      " Applying codeAction to the selected region.
      " Example: `<leader>aap` for current paragraph
      xmap <leader>a  <Plug>(coc-codeaction-selected)
      nmap <leader>a  <Plug>(coc-codeaction-selected)

      " Remap keys for applying codeAction to the current buffer.
      nmap <leader>ac  <Plug>(coc-codeaction)
      " Apply AutoFix to problem on the current line.
      nmap <leader>qf  <Plug>(coc-fix-current)

      " Run the Code Lens action on the current line.
      nmap <leader>cl  <Plug>(coc-codelens-action)

      " Map function and class text objects
      " NOTE: Requires 'textDocument.documentSymbol' support from the language server.
      xmap if <Plug>(coc-funcobj-i)
      omap if <Plug>(coc-funcobj-i)
      xmap af <Plug>(coc-funcobj-a)
      omap af <Plug>(coc-funcobj-a)
      xmap ic <Plug>(coc-classobj-i)
      omap ic <Plug>(coc-classobj-i)
      xmap ac <Plug>(coc-classobj-a)
      omap ac <Plug>(coc-classobj-a)

      " Remap <C-f> and <C-b> for scroll float windows/popups.
      if has('nvim-0.4.0') || has('patch-8.2.0750')
        nnoremap <silent><nowait><expr> <C-f> coc#float#has_scroll() ? coc#float#scroll(1) : "\<C-f>"
        nnoremap <silent><nowait><expr> <C-b> coc#float#has_scroll() ? coc#float#scroll(0) : "\<C-b>"
        inoremap <silent><nowait><expr> <C-f> coc#float#has_scroll() ? "\<c-r>=coc#float#scroll(1)\<cr>" : "\<Right>"
        inoremap <silent><nowait><expr> <C-b> coc#float#has_scroll() ? "\<c-r>=coc#float#scroll(0)\<cr>" : "\<Left>"
        vnoremap <silent><nowait><expr> <C-f> coc#float#has_scroll() ? coc#float#scroll(1) : "\<C-f>"
        vnoremap <silent><nowait><expr> <C-b> coc#float#has_scroll() ? coc#float#scroll(0) : "\<C-b>"
      endif

      " Use CTRL-S for selections ranges.
      " Requires 'textDocument/selectionRange' support of language server.
      nmap <silent> <C-s> <Plug>(coc-range-select)
      xmap <silent> <C-s> <Plug>(coc-range-select)

      " Add `:Format` command to format current buffer.
      command! -nargs=0 Format :call CocActionAsync('format')

      " Add `:Fold` command to fold current buffer.
      command! -nargs=? Fold :call     CocAction('fold', <f-args>)

      " Add `:OR` command for organize imports of the current buffer.
      command! -nargs=0 OR   :call     CocActionAsync('runCommand', 'editor.action.organizeImport')

      " Add (Neo)Vim's native statusline support.
      " NOTE: Please see `:h coc-status` for integrations with external plugins that
      " provide custom statusline: lightline.vim, vim-airline.
      set statusline^=%{coc#status()}%{get(b:,'coc_current_function',${dsquotes})}

      " Mappings for CoCList
      " Show all diagnostics.
      nnoremap <silent><nowait> <space>a  :<C-u>CocList diagnostics<cr>
      " Manage extensions.
      nnoremap <silent><nowait> <space>e  :<C-u>CocList extensions<cr>
      " Show commands.
      nnoremap <silent><nowait> <space>c  :<C-u>CocList commands<cr>
      " Find symbol of current document.
      nnoremap <silent><nowait> <space>o  :<C-u>CocList outline<cr>
      " Search workspace symbols.
      nnoremap <silent><nowait> <space>s  :<C-u>CocList -I symbols<cr>
      " Do default action for next item.
      nnoremap <silent><nowait> <space>j  :<C-u>CocNext<CR>
      " Do default action for previous item.
      nnoremap <silent><nowait> <space>k  :<C-u>CocPrev<CR>
      " Resume latest coc list.
      nnoremap <silent><nowait> <space>p  :<C-u>CocListResume<CR>

      autocmd BufWrite * call CocAction('format')

      " ctags path
      let g:tagbar_ctags_bin = '${pkgs.universal-ctags}/bin/ctags'
    '';
    plugins = with pkgs.vimPlugins; [
      nerdtree
      nerdtree-git-plugin
      vim-devicons
      ctrlp-vim
      vim-nix
      tagbar
      coc-nvim
    ];
    extraPackages = with pkgs; [
      nodejs-17_x
    ];
  };
}