Javascript calling smarty

[eluser]Unknown[/eluser]
2nd question: is calling variable on tpl to be used on javascript function

when i put the function on the .tpl ( internal script) it work but on javascript external i do'nt have idea the variable shall be the same as in the tpl or in the php file

for example

Code:

{literal} [removed]

  function autoPostToFeed(url) {
  'post',
  {
   video : "{/literal}{$video_link}{literal}"
  }
}
[removed] {/literal}

the external js using this (internal scxript) is working

but when i want to add it to the same js !!!
i do'nt know how to call the variable used on the details.tpl this varible{$video_link}

Code:

function autoPostToFeed(url) {
  'post',
  {
   video : "{$video_link}"
  }
}

---------------------------------------------------------
same thing for another varible
on tpl

Code:

{$facebook_image_src }

on php

Code:

$facebook_image_src = show_thumb($video['uniq_id']);
.......
$smarty->assign('facebook_image_src', $facebook_image_src);

on external js i testest many but still not working ?

Code:

var poster = ''