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function image_resize_filter_get_images in Image Resize Filter 7

Same name and namespace in other branches
  1. 8 image_resize_filter.module \image_resize_filter_get_images()
  2. 6 image_resize_filter.module \image_resize_filter_get_images()

Parsing function to locate all images in a piece of text that need replacing.

Parameters

array $settings: An array of settings that will be used to identify which images need updating. Includes the following:

  • image_locations: An array of acceptable image locations. May contain any of the following values: "remote". Remote image will be downloaded and saved locally. This procedure is intensive as the images need to be retrieved to have their dimensions checked.

string $text: The text to be updated with the new img src tags.

1 call to image_resize_filter_get_images()
image_resize_filter_process_filter in ./image_resize_filter.module
Filter callback function.

File

./image_resize_filter.module, line 237
After adding to a text format, this filter will parse the contents of submitted content and automatically scale image files to match the set dimensions of img tags.

Code

function image_resize_filter_get_images($settings, $text) {
  $images = array();

  // Find all image tags, ensuring that they have a src.
  $matches = array();
  preg_match_all('/((<a [^>]*>)[ ]*)?(<img[^>]*?src[ ]*=[ ]*"([^"]+)"[^>]*>)/i', $text, $matches);

  // Loop through matches and find if replacements are necessary.
  // $matches[0]: All complete image tags and preceding anchors.
  // $matches[1]: The anchor tag of each match (if any).
  // $matches[2]: The anchor tag and trailing whitespace of each match (if any).
  // $matches[3]: The complete img tag.
  // $matches[4]: The src value of each match.
  foreach ($matches[0] as $key => $match) {
    $has_link = (bool) $matches[1][$key];
    $img_tag = $matches[3][$key];

    // Extract the query string (image style token) if any from the url.
    $src_query = parse_url($matches[4][$key], PHP_URL_QUERY);
    if ($src_query) {
      $src = substr($matches[4][$key], 0, -strlen($src_query) - 1);
    }
    else {
      $src = $matches[4][$key];
    }
    $resize = NULL;
    $image_size = NULL;
    $attributes = array();

    // Find attributes of this image tag.
    $attribute_matches = array();
    preg_match_all('/([\\w\\-]+)[ ]*=[ ]*"([^"]*)"/i', $img_tag, $attribute_matches);
    foreach ($attribute_matches[0] as $key => $match) {
      $attribute = $attribute_matches[1][$key];
      $attribute_value = $attribute_matches[2][$key];
      $attributes[$attribute] = $attribute_value;
    }

    // Height and width need to be matched specifically because they may come as
    // either an HTML attribute or as part of a style attribute. FCKeditor
    // specifically has a habit of using style tags instead of height and width.
    foreach (array(
      'width',
      'height',
    ) as $property) {
      $property_matches = array();
      preg_match_all('/[ \'";]' . $property . '[ ]*([=:])[ ]*"?([0-9]+)(%?)"?/i', $img_tag, $property_matches);

      // If this image uses percentage width or height, do not process it.
      if (in_array('%', $property_matches[3])) {
        $resize = FALSE;
        break;
      }

      // In the odd scenario there is both a style="width: xx" and a width="xx"
      // tag, base our calculations off the style tag, since that's what the
      // browser will display.
      $property_key = 0;
      $property_count = count($property_matches[1]);
      if ($property_count) {
        $property_key = array_search(':', $property_matches[1]);
      }
      $attributes[$property] = !empty($property_matches[2][$property_key]) ? $property_matches[2][$property_key] : '';
    }

    // Determine if this is a local or remote file.
    $base_path = base_path();
    $location = 'unknown';
    if (strpos($src, $base_path) === 0) {
      $location = 'local';
    }
    elseif (preg_match('/http[s]?:\\/\\/' . preg_quote($_SERVER['HTTP_HOST'] . $base_path, '/') . '/', $src)) {
      $location = 'local';
    }
    elseif (strpos($src, 'http') === 0) {
      $location = 'remote';
    }

    // If not resizing images in this location, continue on to the next image.
    if (!in_array($location, $settings['image_locations'])) {
      continue;
    }

    // Convert the URL to a local path.
    $local_path = NULL;
    if ($location == 'local') {

      // Remove the http:// and base path.
      $local_path = preg_replace('/(http[s]?:\\/\\/' . preg_quote($_SERVER['HTTP_HOST'], '/') . ')?' . preg_quote(base_path(), '/') . '/', '', $src, 1);

      // Build a list of acceptable language prefixes.
      $lang_codes = '';
      if (array_key_exists('locale-url', variable_get('language_negotiation_language', array())) && variable_get('locale_language_negotiation_url_part', 0) == 0) {
        $languages = language_list();
        $lang_codes = array();
        foreach ($languages as $key => $language) {
          if ($language->prefix) {
            $lang_codes[$key] = preg_quote($language->prefix, '!');
          }
        }
        $lang_codes = $lang_codes ? '((' . implode('|', $lang_codes) . ')/)?' : '';
      }

      // Convert to a public file system URI.
      $directory_path = file_stream_wrapper_get_instance_by_scheme('public')
        ->getDirectoryPath() . '/';
      if (preg_match('!^' . preg_quote($directory_path, '!') . '!', $local_path)) {
        $local_path = 'public://' . preg_replace('!^' . preg_quote($directory_path, '!') . '!', '', $local_path);
      }
      elseif (preg_match('!^(\\?q\\=)?' . $lang_codes . 'system/files/!', $local_path)) {
        $local_path = 'private://' . preg_replace('!^(\\?q\\=)?' . $lang_codes . 'system/files/!', '', $local_path);
      }
      $local_path = rawurldecode($local_path);
    }

    // If this is an Image preset, generate the source image if necessary.
    // Formatted as "uri://styles/[style-name]/[schema-name]/[original-path]".
    $image_style_matches = array();
    $scheme = file_uri_scheme($local_path);
    if (!file_exists($local_path) && preg_match('!^' . $scheme . '://styles/([a-z0-9_\\-]+)/([a-z0-9_\\-]+)/(.*)$!i', $local_path, $image_style_matches) && function_exists('image_style_path')) {
      $style_name = $image_style_matches[1];
      $original_path = $scheme . '://' . $image_style_matches[3];
      if ($style = image_style_load($style_name)) {
        image_style_create_derivative($style, $original_path, $local_path);
      }
    }

    // If this is a remote image, retrieve it to check its size.
    if ($location == 'remote') {

      // Basic flood prevention on remote images.
      $resize_threshold = variable_get('image_resize_filter_threshold', 10);
      if (!flood_is_allowed('image_resize_filter_remote', $resize_threshold, 120)) {
        drupal_set_message(t('Image resize threshold of @count remote images has been reached. Please use fewer remote images.', array(
          '@count' => $resize_threshold,
        )), 'error', FALSE);
        continue;
      }
      flood_register_event('image_resize_filter_remote', 120);
      $result = drupal_http_request($src);
      if ($result->code == 200) {
        $tmp_file = drupal_tempnam('temporary://', 'image_resize_filter_');
        $handle = fopen($tmp_file, 'w');
        fwrite($handle, $result->data);
        fclose($handle);
        $local_path = $tmp_file;
      }
    }

    // Get the image size.
    if (is_file($local_path)) {
      $image_size = @getimagesize($local_path);
    }

    // All this work and the image isn't even there. Bummer. Next image please.
    if (empty($image_size)) {
      image_resize_filter_delete_temp_file($location, $local_path);
      continue;
    }
    $actual_width = (int) $image_size[0];
    $actual_height = (int) $image_size[1];

    // If either height or width is missing, calculate the other.
    if (empty($attributes['width']) && empty($attributes['height'])) {
      $attributes['width'] = $actual_width;
      $attributes['height'] = $actual_height;
    }
    if (empty($attributes['height']) && is_numeric($attributes['width'])) {
      $ratio = $actual_height / $actual_width;
      $attributes['height'] = (int) round($ratio * $attributes['width']);
    }
    elseif (empty($attributes['width']) && is_numeric($attributes['height'])) {
      $ratio = $actual_width / $actual_height;
      $attributes['width'] = (int) round($ratio * $attributes['height']);
    }

    // If a percentage has been used in either width or height, and the other
    // attribute is not set at all, then set the missing attribute to an empty
    // string in $attributes. $resize is used because it hasn't otherwise
    // been operated on since the check for percentages.
    if ($resize === FALSE) {
      $attributes['height'] = isset($attributes['height']) ? $attributes['height'] : '';
      $attributes['width'] = isset($attributes['width']) ? $attributes['width'] : '';
    }

    // Determine if this image requires a resize.
    if (!isset($resize)) {
      $resize = $actual_width != $attributes['width'] || $actual_height != $attributes['height'];
    }

    // Skip processing if the image is a remote tracking image.
    if ($location == 'remote' && $actual_width == 1 && $actual_height == 1) {
      image_resize_filter_delete_temp_file($location, $local_path);
      continue;
    }

    // Check the image extension by name.
    $extension_matches = array();
    preg_match('/\\.([a-zA-Z0-9]+)$/', $src, $extension_matches);
    if (!empty($extension_matches)) {
      $extension = strtolower($extension_matches[1]);
    }
    elseif (isset($image_size['mime'])) {
      switch ($image_size['mime']) {
        case 'image/png':
          $extension = 'png';
          break;
        case 'image/gif':
          $extension = 'gif';
          break;
        case 'image/jpeg':
        case 'image/pjpeg':
          $extension = 'jpg';
          break;
      }
    }

    // If we're not certain we can resize this image, skip it.
    if (!isset($extension) || !in_array(strtolower($extension), array(
      'png',
      'jpg',
      'jpeg',
      'gif',
    ))) {
      image_resize_filter_delete_temp_file($location, $local_path);
      continue;
    }

    // If getting this far, the image exists and is not the right size, needs
    // to be saved locally from a remote server, or needs attributes added.
    // Add all information to a list of images that need resizing.
    $images[] = array(
      'expected_size' => array(
        'width' => $attributes['width'],
        'height' => $attributes['height'],
      ),
      'actual_size' => array(
        'width' => $image_size[0],
        'height' => $image_size[1],
      ),
      'attributes' => $attributes,
      'resize' => $resize,
      'img_tag' => $img_tag,
      'has_link' => $has_link,
      'original' => $src,
      'original_query' => $src_query,
      'location' => $location,
      'local_path' => $local_path,
      'mime' => $image_size['mime'],
      'extension' => $extension,
    );
  }
  return $images;
}