" Helper methods for viml

" insert inserted to line at position, use ... when result is too long
" line should only contains character has strwidth equals 1
function! coc#helper#str_compose(line, position, inserted) abort
  let width = strwidth(a:line)
  let text = a:inserted
  let res = a:line
  let need_truncate = a:position + strwidth(text) + 1 > width
  if need_truncate
    let remain = width - a:position - 3
    if remain < 2
      " use text for full line, use first & end of a:line, ignore position
      let res = strcharpart(a:line, 0, 1)
      let w = strwidth(res)
      for i in range(strchars(text))
        let c = strcharpart(text, i, 1)
        let a = strwidth(c)
        if w + a <= width - 1
          let w = w + a
          let res = res.c
        endif
      endfor
      let res = res.strcharpart(a:line, w)
    else
      let res = strcharpart(a:line, 0, a:position)
      let w = strwidth(res)
      for i in range(strchars(text))
        let c = strcharpart(text, i, 1)
        let a = strwidth(c)
        if w + a <= width - 3
          let w = w + a
          let res = res.c
        endif
      endfor
      let res = res.'..'
      let w = w + 2
      let res = res.strcharpart(a:line, w)
    endif
  else
    let first = strcharpart(a:line, 0, a:position)
    let res = first.text.strcharpart(a:line, a:position + strwidth(text))
  endif
  return res
endfunction

" Return new dict with keys removed
function! coc#helper#dict_omit(dict, keys) abort
  let res = {}
  for key in keys(a:dict)
    if index(a:keys, key) == -1
      let res[key] = a:dict[key]
    endif
  endfor
  return res
endfunction