{ config, options, lib, pkgs, ... }:

with lib;
with lib.my;
let cfg = config.modules.editors.vim;
in {
  options.modules.editors.vim = {
    enable = mkBoolOpt false;
  };

  config = mkIf cfg.enable {
    user.packages = with pkgs; [
      editorconfig-core-c
      unstable.neovim
    ];

    # = TODO something like this n00b.
    # builtins.concatStringsSep "\n" [
    #   (lib.strings.fileContents ./base.vim)
    #   (lib.strings.fileContents ./plugins.vim)
    #   (lib.strings.fileContents ./lsp.vim)

    #   # this allows you to add lua config files
    #   ''
    #     lua << EOF
    #     ${lib.strings.fileContents ./config.lua}
    #     ${lib.strings.fileContents ./lsp.lua}
    #     EOF
    #   ''
    # ];

    extraConfig = ''
      set tabstop=2
      set showmatch
      set shiftwidth=2
      set noexpandtab
      set autoindent
      
      set foldmethod=indent   " fold based on indent
      set number
      set nocompatible
      set relativenumber
      set showtabline=2
      set autowriteall
      		syntax on
      set list lcs=tab:\|\ 
      filetype plugin on
      
      set termguicolors
      let ayucolor="dark"
      colorscheme ayu
      
      " window
      nmap <leader>wh  :topleft  vnew<CR>
      nmap <leader>wl :botright vnew<CR>
      nmap <leader>wk    :topleft  new<CR>
      nmap <leader>wj  :botright new<CR>
      
      let mapleader = "\<Space>"
      
      " lightline colorscheme
      let g:lightline = {
      			\ 'colorscheme': 'seoul256',
      			\ }
      
      " moving splits with vim movements.
      :tnoremap <A-h> <C-\><C-N><C-w>h
      :tnoremap <A-j> <C-\><C-N><C-w>j
      :tnoremap <A-k> <C-\><C-N><C-w>k
      :tnoremap <A-l> <C-\><C-N><C-w>l
      :inoremap <A-h> <C-\><C-N><C-w>h
      :inoremap <A-j> <C-\><C-N><C-w>j
      :inoremap <A-k> <C-\><C-N><C-w>k
      :inoremap <A-l> <C-\><C-N><C-w>l
      :nnoremap <A-h> <leader>h
      :nnoremap <A-j> <leader>j
      :nnoremap <A-k> <leader>k
      :nnoremap <A-l> <leader>l
      :nnoremap <F5> "=strftime("%Y-%m-%d %H:%M:")
      :inoremap <F5> <C-R>=strftime("%Y-%m-%d %H:%M:")
      
      " exit normal mode in terminal
      :tnoremap <C-n> <C-\><C-n>
      
      let g:syntastic_always_populate_loc_list = 1
      let g:syntastic_auto_loc_list = 1
      let g:syntastic_check_on_open = 1
      let g:syntastic_check_on_wq = 0
      
      let g:rainbow_active = 0
      autocmd BufReadPost,BufNewFile c,py,nix RainbowParenthesesToggleAll
      
      " keyboard commands
      map <leader>t :NERDTreeToggle<CR>
      map <leader>s :w<CR>
      map <leader>q :wq<CR>
      map <leader>r :RainbowParenthesesToggleAll<CR>
      map <leader>zs :ZettelSearch<CR>
      map <leader>zo :ZettelOpen<CR>
      map <leader>zn :ZettelNew<CR>
      
      
      " NERDTree 
      " open on directory
      autocmd StdinReadPre * let s:std_in=1
      
      " coc
      "
      " if hidden is not set, TextEdit might fail.
      set hidden
      
      " Some servers have issues with backup files, see #649
      set nobackup
      set nowritebackup
      
      " Better display for messages
      set cmdheight=2
      
      " You will have bad experience for diagnostic messages when it's default 4000.
      set updatetime=300
      
      " don't give |ins-completion-menu| messages.
      set shortmess+=c
      
      " always show signcolumns
      set signcolumn=yes
      
      " Use tab for trigger completion with characters ahead and navigate.
      " Use command ':verbose imap <tab>' to make sure tab is not mapped by other plugin.
      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
      
      " Use <c-space> to trigger completion.
      inoremap <silent><expr> <c-space> coc#refresh()
      
      " Use <cr> to confirm completion, `<C-g>u` means break undo chain at current position.
      " Coc only does snippet and additional edit on confirm.
      inoremap <expr> <cr> pumvisible() ? "\<C-y>" : "\<C-g>u\<CR>"
      " Or use `complete_info` if your vim support it, like:
      " inoremap <expr> <cr> complete_info()["selected"] != "-1" ? "\<C-y>" : "\<C-g>u\<CR>"
      
      " Use `[g` and `]g` to navigate diagnostics
      nmap <silent> [g <Plug>(coc-diagnostic-prev)
      nmap <silent> ]g <Plug>(coc-diagnostic-next)
      
      " Remap keys for gotos
      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>')
      	else
      		call CocAction('doHover')
      	endif
      endfunction
      
      " Highlight symbol under cursor on CursorHold
      autocmd CursorHold * silent call CocActionAsync('highlight')
      
      " Remap for rename current word
      nmap <leader>rn <Plug>(coc-rename)
      
      " Remap for format selected region
      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
      
      " Remap for do codeAction of selected region, ex: `<leader>aap` for current paragraph
      xmap <leader>a  <Plug>(coc-codeaction-selected)
      nmap <leader>a  <Plug>(coc-codeaction-selected)
      
      " Remap for do codeAction of current line
      nmap <leader>ac  <Plug>(coc-codeaction)
      " Fix autofix problem of current line
      nmap <leader>qf  <Plug>(coc-fix-current)
      
      " Create mappings for function text object, requires document symbols feature of languageserver.
      xmap if <Plug>(coc-funcobj-i)
      xmap af <Plug>(coc-funcobj-a)
      omap if <Plug>(coc-funcobj-i)
      omap af <Plug>(coc-funcobj-a)
      
      " Use <C-d> for select selections ranges, needs server support, like: coc-tsserver, coc-python
      nmap <silent> <C-d> <Plug>(coc-range-select)
      xmap <silent> <C-d> <Plug>(coc-range-select)
      
      " Use `:Format` to format current buffer
      command! -nargs=0 Format :call CocAction('format')
      
      " Use `:Fold` to fold current buffer
      command! -nargs=? Fold :call     CocAction('fold', <f-args>)
      
      " use `:OR` for organize import of current buffer
      command! -nargs=0 OR   :call     CocAction('runCommand', 'editor.action.organizeImport')
      
      " Add status line support, for integration with other plugin, checkout `:h coc-status`
      " set statusline^=%{coc#status()}%{get(b:,'coc_current_function',"")}
      
      " Using CocList
      " Show all diagnostics
      nnoremap <silent> <space>a  :<C-u>CocList diagnostics<cr>
      " Manage extensions
      nnoremap <silent> <space>e  :<C-u>CocList extensions<cr>
      " Show commands
      nnoremap <silent> <space>c  :<C-u>CocList commands<cr>
      " Find symbol of current document
      nnoremap <silent> <space>o  :<C-u>CocList outline<cr>
      " Search workspace symbols
      nnoremap <silent> <space>s  :<C-u>CocList -I symbols<cr>
      " Do default action for next item.
      nnoremap <silent> <space>j  :<C-u>CocNext<CR>
      " Do default action for previous item.
      nnoremap <silent> <space>k  :<C-u>CocPrev<CR>
      " Resume latest coc list
      nnoremap <silent> <space>p  :<C-u>CocListResume<CR>
      
      au BufNewFile,BufRead *.frag,*.vert,*.fp,*.vp,*.glsl setf glsl
    '';

    extraPackages = with pkgs; [
      vim-nix
      fzf-vim
      vim-elixir
      emmet-vim
      nerdtree
      goyo-vim
      vim-sneak
      lightline-vim
      csv-vim
      vimwiki
      coc-nvim
      coc-json
      coc-python
      coc-pairs
      coc-emmet
      emmet-vim
      LanguageClient-neovim
      ayu-vim
      rainbow_parentheses-vim
      vim-surround
      vim-fugitive
      #iron-nvim
      #nvim-colorizer
      vim-devicons
      # testing
      #vim-processing
      #vim-tidal
      taskwiki
      vim-zettel
    ];

    environment.shellAliases = {
      vim = "nvim";
      v   = "nvim";
      k   = "vim -c :VimwikiIndex";
      kz  = "vim -c :VimwikiIndex -c :ZettelNew";
    };
  };
}