" Joiner. Ability to join lines in a text object.

if ! exists('g:joiner_include_bindings')
  let g:joiner_include_bindings = 1
endif

if ! exists('g:joiner_leader')
  let g:joiner_leader = '<leader>+'
endif

function! s:join_text_literal(yanked, yankedtype) abort
  if !exists('g:joiner_join_text')
    let g:joiner_join_text = ' '
  endif
  return join(a:yanked, g:joiner_join_text)
endfunction

function! s:join_text_collapse(yanked, yankedtype) abort
  let changed = []
  if !exists('g:joiner_join_text')
    let g:joiner_join_text = ' '
  endif
  for y in a:yanked
    call add(changed, substitute(y, '^\s\+', '', 'g'))
  endfor
  return join(changed, g:joiner_join_text)
endfunction

function! s:joiner_do(type, ...) abort
  if a:0
    psilent exe "norm! gvy"
  elseif a:type == 'line'
    " yank the text described by the motion
    silent exe "norm! '[V']y"
  else
    silent exe "norm! `[v`]y"
  endif

  let yanked = getreg('"', 1, v:true)
  let yankedtype = getregtype('"')

  if !exists('g:joiner_join_text')
    let g:joiner_join_text = ' '
  endif

  let changed = [g:JoinerJoinText(yanked, yankedtype)]

  call setreg('"', changed, yankedtype)

  norm gvp

  " Reset the yanked text to what it was originally.
  call setreg('"', yanked, yankedtype)
endfunction

noremap <Plug>(joiner-leader)
      \ :<C-u>let g:JoinerJoinText=function("<SID>join_text_collapse")<cr>
      \:<C-u>let g:joiner_join_text=' '<cr>
      \:<C-u>set operatorfunc=<SID>joiner_do<cr>
      \g@

vnoremap <Plug>(joiner-leader)
      \ :<C-u>let g:JoinerJoinText=function("<SID>join_text_collapse")<cr>
      \:<C-u>let g:joiner_join_text=' '<cr>
      \gv:<C-u>call joiner_do(visualmode(), 1)<cr>

if g:joiner_include_bindings
  exec printf('nmap %s <Plug>(joiner-leader)', g:joiner_leader)
  exec printf('vmap %s <Plug>(joiner-leader)', g:joiner_leader)
endif