function! utils#select(items, opts, on_choice) abort
  let prompt = get(a:opts, 'prompt', 'Select one of:')
  let s:format_item = get(a:opts, 'format_item', {item->item})
  let items = map(a:items[:], {idx,item-> (idx + 1) .. ': ' .. s:format_item(item)})

  let choice = inputlist(insert(items, prompt))

  if choice > 0 && choice <= len(a:items)
    call a:on_choice(a:items[choice-1], choice)
  else
    call a:on_choice(v:null, v:null)
  endif
endfunction

function! utils#echo(msg) abort
  echo a:msg
endfunction
function! utils#let(var_name, value, ...) abort
  let value = a:value
  let raw_value = get(a:000, 0, 0)
  if !raw_value
    let value = '"' .. a:value .. '"'
  endif
  execute 'let ' ..a:var_name .. '=' .. value
endfunction

function! utils#handler(item, idx) abort
  echo a:item a:idx
endfunction

" example
" lua vim.ui.select({'Fire', 'Air', 'Water', 'Earth'}, {}, vim.fn['utils#handler'])
" call utils#select(['Fire', 'Air', 'Water', 'Earth'], {}, function('utils#handler'))

" call utils#select(['Fire', 'Air', 'Water', 'Earth'], {}, {item,_->item != v:null ? utils#echo(item) : ''})
" call utils#select(['Fire', 'Air', 'Water', 'Earth'], {}, {item,num->num != v:null ? utils#let('b:selected', item) : ''})
" if exists('b:selected')
"   echo b:selected
"   unlet b:selected
" endif

" with options
" call utils#select(['Fire', 'Air', 'Water', 'Earth'], {
"   \   'prompt': 'Select Element:',
"   \   'format_item': {item->'The ' .. item}
"   \ }, function('utils#handler'))
" lua << EOF
" vim.ui.select({'Fire', 'Air', 'Water', 'Earth'}, {
"   prompt = 'Select Element:',
"   format_item = function(item) return 'The ' .. item end
"   }, vim.fn['utils#handler'])
" EOF