//get image from external url and save to wordpress media library and set as featured image

$url = "http://yoursite.com/wp-content/uploads/2011/02/14/image_name.jpg";
$post_id = 1;
$att_id = aladdin_get_image_id($url);
if($att_id){
set_post_thumbnail( $post_id, $att_id );
}else{
// Need to require these files
if ( !function_exists('media_handle_upload') ) {
require_once(ABSPATH . "wp-admin" . '/includes/image.php');
require_once(ABSPATH . "wp-admin" . '/includes/file.php');
require_once(ABSPATH . "wp-admin" . '/includes/media.php');
}

$tmp = download_url( $url );
if( is_wp_error( $tmp ) ){
// download failed, handle error
}

$desc = get_the_title($post_id);
$file_array = array();

// Set variables for storage
// fix file filename for query strings
preg_match('/[^?]+.(jpg|jpe|jpeg|gif|png)/i', $url, $matches);
$file_array['name'] = basename($matches[0]);
$file_array['tmp_name'] = $tmp;

// If error storing temporarily, unlink
if ( is_wp_error( $tmp ) ) {
@unlink($file_array['tmp_name']);
$file_array['tmp_name'] = '';
}

// do the validation and storage stuff
$id = media_handle_sideload( $file_array, $post_id, $desc );

// If error storing permanently, unlink
if ( is_wp_error($id) ) {
@unlink($file_array['tmp_name']);
return $id;
}

set_post_thumbnail( $post_id, $id );

// retrieves the attachment ID from the file URL
function aladdin_get_image_id($image_url) {
global $wpdb;
$attachment = $wpdb->get_col($wpdb->prepare("SELECT ID FROM $wpdb->posts WHERE guid='%s';", $image_url ));
return $attachment[0];
}

function throttle(func, wait) {
    var timeout;
    return function() {
        var context = this, args = arguments;
        if (!timeout) {
            // the first time the event fires, we setup a timer, which 
            // is used as a guard to block subsequent calls; once the 
            // timer's handler fires, we reset it and create a new one
            timeout = setTimeout(function() {
                timeout = null;
                func.apply(context, args);
            }, wait);
        }
    }
}

//example
document.addEventListener("scroll", throttle(function() {
    console.log("test");
}, 2000), false);

http://stackoverflow.com/questions/5031501/how-to-rate-limit-ajax-requests

use this code

add_filter( 'redirect_canonical', 'redirectFrontPageFix', 1, 2 );

function redirectFrontPageFix( $redirect_url, $requested_url )
{
if ( strpos( $_SERVER['REQUEST_URI'], '/blog/page/' ) === 0 )
{
return false;
}
return $redirect_url;
}

source:

https://wpml.org/forums/topic/blogs-page-2-inaccessible/

Shopify advanced front end search links:

https://www.google.com.eg/search?q=shopify+search+in+a+collection

http://docs.shopify.com/manual/your-store/dashboard/storefront-search

http://docs.shopify.com/pos/operating-pos/products/view-search-products

http://docs.shopify.com/manual/configuration/store-customization/page-specific/collections/subcategories

http://docs.shopify.com/manual/configuration/store-customization/advanced-navigation/how-to-add-swiftype-search-to-your-shopify-store

http://docs.shopify.com/manual/configuration/store-customization/page-specific/collections/filter-a-collection-using-product-tags

http://docs.shopify.com/themes/theme-development/templates/search-liquid

http://www.microapps.com/blogs/english/13370313-shopify-store-search-limited-by-product-type

custom code to search by product type:

/////////////////////////////////////
 //  customizations by alhoseany
 /////////////////////////////////////
 jQuery(function() {

var query = '';
 var text = jQuery('.search_menu .search_box .txtbox');
 var option = jQuery('#select_product_type');
 var selection = '';

var prevValue = text.val();
 if(prevValue.indexOf("product_type:") != -1){
 var prevValue1 = prevValue.split(" AND ");
 var prevValue2 = prevValue1[0].split("product_type:");
 text.val(prevValue1[1]);
 option.val(prevValue2[1]);
 jQuery('.breadcrumb > li').last().html('Product Type: '+ prevValue2[1] + ' and Search Keyword: ' + prevValue1[1]);
 }
 jQuery('.select_product_type_cont').show();

jQuery('.search_menu form').submit(function() {
 if(option.val() != ''){
 selection = "product_type:" + option.val();
 query = selection+ " AND " + text.val();
 text.val(query);
 }

});

});

      <div class="select_product_type_cont">
        <select name="select_product_type" id="select_product_type" class="form-control">
          <option value="">Select Product Type</option>
          {% for product_type in shop.types %}
          <option value="{{ product_type }}">{{ product_type }}</option>
          {% endfor %}
        </select>
      </div>

/* select product type in search */
.select_product_type_cont {
  margin-bottom: 15px;
  display:none;
}

advanced solution. using tags like this:

actor_actor name

artist_artist name

author_author name

  <div class="menu_c search_menu">
      <div class="select_product_type_cont">
        <select name="select_product_type" id="select_product_type" class="form-control search-by" data-search-by="product_type:">
          <option value="">Search by Product Type</option>
          {% for product_type in shop.types %}
          <option value="{{ product_type }}">{{ product_type }}</option>
          {% endfor %}
        </select>
        <select name="select_product_vendor" id="select_product_vendor" class="form-control search-by" data-search-by="vendor:">
          <option value="">Search by Brand</option>
          {% for product_vendor in shop.vendors %}
          <option value="{{ product_vendor }}">{{ product_vendor }}</option>
          {% endfor %}
        </select>
        
        <select name="select_product_actor" id="select_product_actor" class="form-control search-by" data-search-by="tag:actor_">
          <option value="">Search by Actor</option>
          {% for tag in collections.all.all_tags %}
            {% if tag contains 'actor_' %}
          		{% assign thistag =  tag | replace_first: '"', ' ' | replace_first: 'actor_', '' %} 	 
          		<option value="{{ thistag }}">{{ thistag }}</option>
            {% endif %}
          {% endfor %}
        </select>
        
        <select name="select_product_artist" id="select_product_artist" class="form-control search-by" data-search-by="tag:artist_">
          <option value="">Search by Artist</option>
          {% for tag in collections.all.all_tags %}
            {% if tag contains 'artist_' %}
          		{% assign thistag =  tag | replace_first: '"', ' ' | replace_first: 'artist_', '' %} 	 
          		<option value="{{ thistag }}">{{ thistag }}</option>
            {% endif %}
          {% endfor %}
        </select>
        
        <select name="select_product_author" id="select_product_author" class="form-control search-by" data-search-by="tag:author_">
          <option value="">Search by Author</option>
          {% for tag in collections.all.all_tags %}
            {% if tag contains 'author_' %}
          		{% assign thistag =  tag | replace_first: '"', ' ' | replace_first: 'author_', '' %} 	 
          		<option value="{{ thistag }}">{{ thistag }}</option>
            {% endif %}
          {% endfor %}
        </select>
        
        <select name="select_product_tag" id="select_product_tag" class="form-control search-by" data-search-by="tag:">
          <option value="">Search by Product Tag</option>
          {% for tag in collections.all.all_tags %}
          {% if tag contains 'author_' %}{% elsif tag contains 'artist_' %}{% elsif tag contains 'actor_' %}{% else %}
          <option value="{{ tag | replace_first: '"', ' ' }}">{{ tag  | replace_first: '"', ' ' }}</option>
          {% endif %}
          {% endfor %}
        </select>
      </div>
    <form action="/search" method="get" role="search">
      <div class="search_box">
        {% unless settings.search_results == 'everything' %}
        <input type="hidden" name="type" value="product">
        {% endunless %}
        <input type="search" name="q" value="{{ search.terms | escape }}" class="txtbox" placeholder="{{ 'general.search.submit' | t }}" aria-label="{{ 'general.search.submit' | t }}">
        <button class="btn btn-link" type="submit" value="{{ 'general.search.submit' | t }}"><span class="fa fa-search"></span></button>
      </div>
    </form>
  </div>

/*----------------
Customizations Styles
-----------------*/

/* Customizations Styles by alhoseany*/

#header #nav .navbar .dropdown-menu li > a {
  color: #e53e2e;
  letter-spacing: 1px;
}

/* select product type in search */
.select_product_type_cont {
  display:none;
}
.select_product_type_cont select {
  margin-bottom: 15px;
}

/////////////////////////////////////
//  customizations by alhoseany
/////////////////////////////////////
  jQuery(function () {

    // query is the search query
    // text is the text input used for serach string
    // searchBy is the select elements for cutom search
    var query = '';
    var text = jQuery('.search_menu .search_box .txtbox');
    var searchBy = jQuery('.select_product_type_cont .search-by');

    // get the search string on page load
    var prevValue = text.val();
    // is there is a previous search string on page load
    var searchByCheck = false;
    // search query text to use in breadcrumb
    var searchByText = '';
    var searchByIndex = 0;
    // iterate through the select elements
    searchBy.each(function () {
      // check if this select element is used in the previous search query and set its load value 
      if (prevValue.indexOf(jQuery(this).data('search-by')) !== -1) {
        var prevValue1 = prevValue.split(" AND ");
        var prevValue2 = prevValue1[searchByIndex].split(jQuery(this).data('search-by'));
        console.log(prevValue1);
        console.log(prevValue2);
        searchByCheck = true;
        if (prevValue2[1]) {
          jQuery(this).val(prevValue2[1]);
          searchByText += "<strong>" + jQuery(this).data('search-by').replace('_', ' ').toUpperCase() + "</strong> " + prevValue2[1] + " , ";
        }
        searchByIndex++;
      }
    });
    if (searchByCheck) {
      var prevValue1 = prevValue.split(" AND ");

      if (prevValue1[prevValue1.length - 1]) {
        text.val(prevValue1[prevValue1.length - 1]);
        searchByText += '<strong>Search Keyword:</strong> ' + prevValue1[prevValue1.length - 1];
      } else {
        // remove last comma
        searchByText = searchByText.replace(/,s*$/, "");
        text.val('');
      }

      jQuery('.breadcrumb > li').last().html(searchByText);
    }
    jQuery('.select_product_type_cont').show();


    jQuery('.search_menu form').submit(function () {
      searchBy.each(function () {
        if (jQuery(this).val() !== '') {
          query += jQuery(this).data('search-by') + jQuery(this).val() + " AND ";
        }
      });
      query += text.val();
      text.val(query);

    });

  });

// Hook in
add_filter( 'woocommerce_checkout_fields' , 'custom_override_checkout_fields' );

// Our hooked in function - $fields is passed via the filter!
function custom_override_checkout_fields( $fields ) {
         // loop by category
    foreach ($fields as $category => $value) {
        // loop by fields
        foreach ($fields[$category] as $field => $property) {
            // remove placeholder property
            unset($fields[$category][$field]['placeholder']);
        }
    }
     
     
     return $fields;
}

sanitize_title($sometext);
// if you want to limit its length
sanitize_title(substr($sometext,0,100))

https://github.com/sgruhier/typeahead-addresspicker

https://developers.google.com/maps/documentation/javascript/examples/places-autocomplete?csw=1

https://developers.google.com/maps/documentation/javascript/examples/places-searchbox

https://developers.google.com/maps/documentation/javascript/examples/places-autocomplete-hotelsearch

https://developers.google.com/maps/documentation/javascript/places-autocomplete

http://ubilabs.github.io/geocomplete/

https://hpneo.github.io/gmaps/examples/geocoding.html

http://refreshless.com/nouislider/

http://lokku.github.io/jquery-nstslider/

http://andreruffert.github.io/rangeslider.js/

you can use json to view what is inside liquid variables in shopify like:

{{product | json}}