Repeatable upload field

so_13646200.php

add_action('admin_init',    'so_13646200_add_post_gallery');
add_action('save_post' , 'so_13646200_update_post_gallery');

function so_13646200_add_post_gallery() {
  add_meta_box(
    'post_gallery',
    'Clients Logo Options',
    'so_13646200_post_gallery_options',
    'post',
    'normal',
    'core'
  );
}

function so_13646200_post_gallery_options() {
  global $post;

  //$custom = get_post_custom($post->ID);
  $gallery_data = get_post_meta($post->ID, 'gallery_data', true);
  ?>

<div id="dynamic_form">

    <div id="field_wrap">
    <?php 
    if (isset($gallery_data['image_url'])) {
      for ($i = 0; $i < count($gallery_data['image_url']); $i++) {
        ?>

        <div class="field_row">

          <div class="field_left">
            <div class="form_field">
              <label>Image URL</label>
              <input type="text"
                     class="meta_image_url"
                     name="gallery[image_url][]"
                     value="<?=$gallery_data['image_url'][$i];?>"
              />
            </div>
            <div class="form_field">
              <label>Image Link</label>
              <input type="text"
                     class="meta_image_link"
                     name="gallery[image_link][]"
                     value="<?=$gallery_data['image_link'][$i];?>"
              />
            </div>
          </div>

          <div class="field_right image_wrap">
            <img src="<?=$gallery_data['image_url'][$i];?>" height="48" width="48" />
          </div>

          <div class="field_right">
            <input class="button" type="button" value="Choose File" onclick="add_image(this)" /><br />
            <input class="button" type="button" value="Remove" onclick="reomove_field(this)" />
          </div>

          <div class="clear" /></div> 
		</div>
        <?php
	  } // endif
	} // endforeach
    ?>
    </div>
	
	<div style="display:none" id="master-row">
	<div class="field_row">
		<div class="field_left">
			<div class="form_field">
				<label>Image URL</label>
				<input class="meta_image_url" value="" type="text" name="gallery[image_url][]" />
			</div>
			<div class="form_field">
				<label>Image Link</label>
				<input class="meta_image_link" value="" type="text" name="gallery[image_link][]" />
			</div>
		</div>
		<div class="field_right image_wrap">
		</div> 
		<div class="field_right"> 
			<input type="button" class="button" value="Choose File" onclick="add_image(this)" />
			<br />
			<input class="button" type="button" value="Remove" onclick="reomove_field(this)" /> 
		</div>
		<div class="clear"></div>
	</div>
	</div>
	
    <div id="add_field_row">
      <input class="button" type="button" value="Add Field" onclick="add_field_row();" />
    </div>

</div>

    <style type="text/css">
      .field_left {
        float:left;
      }

      .field_right {
        float:left;
        margin-left:10px;
      }

      .clear {
        clear:both;
      }

      #dynamic_form {
        width:580px;
      }

      #dynamic_form input[type=text] {
        width:300px;
      }

      #dynamic_form .field_row {
        border:1px solid #999;
        margin-bottom:10px;
        padding:10px;
      }

      #dynamic_form label {
        padding:0 6px;
      }
    </style>

	<script type="text/javascript">
		function add_image(obj) {
			var parent=jQuery(obj).parent().parent('div.field_row');
			var inputField = jQuery(parent).find("input.meta_image_url");

			tb_show('', 'media-upload.php?TB_iframe=true');

			window.send_to_editor = function(html) {
				var url = jQuery(html).find('img').attr('src');
				inputField.val(url);
				jQuery(parent)
				.find("div.image_wrap")
				.html('<img src="'+url+'" height="48" width="48" />');

				// inputField.closest('p').prev('.awdMetaImage').html('<img height=120 width=120 src="'+url+'"/><p>URL: '+ url + '</p>'); 
			 
				tb_remove();
			};

			return false;  
		}

		function reomove_field(obj) {
			var parent=jQuery(obj).parent().parent();
			//console.log(parent)
			parent.remove();
		}
				
		function add_field_row() {
			var row = jQuery('#master-row').html();
			jQuery(row).appendTo('#field_wrap');
		}
	</script>

  <?php
}

function so_13646200_update_post_gallery() {
	global $post;
	if ($_POST['gallery']) {
		$gallery_data=array();
		for ($i = 0; $i < count($_POST['gallery']['image_url']); $i++) {
			if ($_POST['gallery']['image_url'][$i] != '') {
				$gallery_data['image_url'][]  = $_POST['gallery']['image_url'][$i];
				$gallery_data['image_link'][] = $_POST['gallery']['image_link'][$i];
			}
		}

		if ($gallery_data) 
			update_post_meta($post->ID, 'gallery_data', $gallery_data);
		else 
			delete_post_meta($post->ID, 'gallery_data');
	} else {
		delete_post_meta($post->ID, 'gallery_data');
	}
}