text: <?php
  	// Check writability of directories
  	$directories_to_check = array(
  		"cache/",
  		"extensions/",
  		"site/extensions/"
  	);
  	foreach ($directories_to_check as $directory) {
  		if (!is_writable(SERVER_ROOT.$directory)) {
  ?>
  <div class="container">
  	<section>
  		<h3>Error</h3>
  		<p>Your <code>/<?=$directory?></code> directory must be writable to install extensions.</p>
  	</section>
  </div>
  <?php
  			$admin->stop();
  		}
  	}
  ?>
  <div class="container">
  	<form method="post" action="<?=DEVELOPER_ROOT?>extensions/install/unpack/" enctype="multipart/form-data">
  		<?php $admin->drawCSRFToken() ?>
  		<input type="hidden" name="MAX_FILE_SIZE" value="<?=BigTree::uploadMaxFileSize()?>" />
  		<section>
  			<?php
  				if ($_SESSION["upload_error"]) {
  			?>
  			<p class="error_message"><?=$_SESSION["upload_error"]?></p>
  			<?php
  					unset($_SESSION["upload_error"]);
  				}
  				
  				$admin->drawPOSTErrorMessage();
  			?>
  			<fieldset>
  				<label>Extension</label>
  				<input type="file" name="file" />
  			</fieldset>
  		</section>
  		<footer>
  			<input type="submit" class="button blue" value="Unpack" />
  		</footer>
  	</form>
  </div>