" Function for commenting out blocks of text.

noremap cd <cmd>set operatorfunc=<sid>comment<cr>g@
nnoremap cdd <cmd>set operatorfunc=<sid>comment<cr>g@_
nnoremap cD <cmd>set operatorfunc=<sid>comment<cr>g@$

" Comment out the rest of the line and put the cursor into insert mode
noremap cdC  c<Plug><SID>(comment-change-object-i)

" Comment out the line and go into insert mode before the first non-blank
" character.
noremap cdcc c<Plug><SID>(comment-change-object-I)

onoremap <Plug><SID>(comment-change-object-i) <cmd>call <sid>change_comment_obj('i')<cr>
onoremap <Plug><SID>(comment-change-object-I) <cmd>call <sid>change_comment_obj('I')<cr>

onoremap i/ <cmd>call <sid>inner_comment(v:operator)<cr>
vnoremap i/ <cmd>call <sid>inner_comment('')<cr>

noremap czd <cmd>set operatorfunc=<sid>uncomment<cr>g@
nnoremap czdd <cmd>set operatorfunc=<sid>uncomment<cr>g@_

function! s:inner_comment(op)
  let [line_com, bstart, bcont, bend, bpad, inl] =
        \ get(s:comment_style, &ft, ['#', '#', '#', '#', 0, 0])
  let lc = escape(line_com, '/')

  if getline('.') =~ printf('\V\^\s\*%s', lc)
    call search(printf('\V\^\s\*\S\(%s\)\@<!', lc), 'W')
    exec "normal! k$m>"
    let l = search(printf('\V\^\s\*\S\(%s\)\@<!', lc), 'bW')
    if l == 0
      normal! 0m<
    else
      exec "normal! j0m<"
    endif

    normal! gvoh

    if a:op == 'c'
      exec printf("normal! \<esc>i%s gv%dll", line_com, len(line_com))
    endif
  else
    let cs = escape(bstart, '/')
    let ce = escape(bend, '/')

    normal! k
    let l2 = search('\V\zs\S\_s\*' . ce, 'Wc')
    exec "normal! m>"
    let l1 = search('\V' . cs . '\S\*\_s\?\zs', 'bW')
    exec "normal! m<gvo"

    if l1 != l2 && len(v:operator) > 0
      exec printf("normal! \<esc>i%s gv%dll", bcont, len(bcont))
    else
      " exec printf("normal! \<esc>i%s gv%dllo%dll", bcont, len(bcont), len(bcont))
    endif
  endif
endfunction

function! s:change_comment_obj(mv) abort
  if v:operator == 'c'
    " This is a cheese to allow the cdcc and cdC commands to be repeated with
    " the dot operator. When in insert mode <left><right><up><down> stop
    " recording into the redobuff. This is a way to get around that.
    "
    " exec "normal! i \<esc>v"
    let [line_com, bstart, bcont, bend, bpad, inl] =
          \ get(s:comment_style, &ft, ['#', '#', '#', '#', 0, 0])
    exec printf("normal! %s   %s \<esc>%dhvl", a:mv, line_com, len(line_com) + 3)
  else
  endif
endfunction

      "  filetype, linecomment, block start, block continue, blockend, blockpad,
      "  inline_support
let s:comment_style = {
      \ 'java': ['//', '/*', ' *', '*/', 1, 1],
      \ 'c':    ['//', '/*', ' *', '*/', 1, 1],
      \ 'cpp':  ['//', '/*', ' *', '*/', 1, 1],
      \ 'vim':  ['"',  '"',  '"',  '"',  0, 0]
      \ }

function! s:uncomment(arg, ...) abort

  let [line_com, bstart, bcont, bend, bpad, inl] =
        \ get(s:comment_style, &ft, ['#', '#', '#', '#', 0, 0])
  let l1 = line("'[")
  let l2 = line("']")

  if inl
    silent exec printf(
          \ 'silent! %s,%s s/\V\zs%s\s\?\ze//', l1, l2, escape(bstart, '/'))
    silent exec printf('silent! %s,%s s/\V\zs\s\?%s\ze//', l1, l2, escape(bend, '/'))
  endif

  silent exec printf('silent! %s,%s s/\V\^\s\*\zs%s\s\?\ze//', l1, l2, escape(line_com, '/'))
  silent exec printf('silent! %s,%s s/\V\^\s\*\zs%s\s\?\ze//', l1, l2, escape(bcont, '/'))
endfunction

function! s:comment(arg, ...) abort
  let cb = { 'arg': a:arg }
  normal! m`

  function! cb.operate(ls, t) dict abort
    let [line_com, bstart, bcont, bend, bpad, inl] = get(s:comment_style, &ft, ['#', '#', '#', '#', 0, 0])
    let smallest = 100
    let ls = a:ls

    if self.arg == 'line' || len(ls) > 1
      for l in ls
        if ! (l =~ '^\s*$')
          let sz = match(l, '^\(\s\+\)\zs\S\ze') + 1
          if sz <= 0
            let sz = 1
          endif

          if sz < smallest && sz > 0
            let smallest = sz
          endif
        endif
      endfor

      if self.arg == 'line'
        let i = 0
        while i < len(ls)
          let ls[i] = substitute(ls[i], printf('\%%%dc', smallest), line_com . ' ', '')
          let i += 1
        endwhile
      else
        if self.arg != 'line' && !inl
          throw "Inline comments not allowed"
        endif

        let ls[0] = substitute(ls[0], '^', bstart . ' ', '')
        let ls[-1] = substitute(ls[-1], '$', ' ' . bend, '')
      endif
    else
      let l = getline('.')
      if l[len(l) - len(ls[0]):] ==# ls[0]
        let ls[0] = printf("%s %s", line_com, ls[0])
      else
        if !inl
          throw "Inline comments not allowed"
        endif
        let ls[0] = printf("%s %s %s", bstart, ls[0], bend)
      endif
    endif

    return ls
  endfunction

  call fieldmarshal#modifytext(a:arg, cb)
  norm ``
endfunction