/** compute URL for a background image based on current time and index
*
* this routine returns a URL to be used as a background image. The
* URL is different depending on the time of day and the $index parameter.
* The latter is thought to be the position of the current item in the
* main navigation (starting at 1) or 0 in case no item in the main
* navigation is current.
*
* Configuration is done via two parameters:
* the path in $this->config['header_banners_directory'] and
* the interval in $this->config['header_banners_interval'].
*
* The interval is expressed in minutes. It means that a particular page
* has the same background image for the duration of the interval and
* another one in the next interval. The banners directory is supposed
* to contain banner files of the correct dimensions, e.g. 980x170.
*
* If the specified directory starts with a '/' it is assumed to start in
* the data root, e.g. something like /areas/exemplum/banners. This will
* eventually lead to a URL of the form
* /file.php/areas/exemplum/banners/mentha-banner.jpg using
* was_file_url()
*
* If the specified directory does NOT start with a '/' it is assumed to
* be a directory relative to the directory where index.php and friends
* live, unless it starts with program/ in which case it is a static dir
* somewhere in the program hierarchy. This is done via was_url().
*
* @param int $index indicates current main navigation item or 0 for none
* @param bool $fully_qualified if TRUE forces the URL to contain a scheme, authority etc.
* @return string ready to use URL
* @uses was_file_url()
* @uses was_url()
*/
function cornelia_get_background_url($index, $fully_qualified = FALSE)
{
global $CFG;
//
// 0 -- sanity checks
//
$path = trim($this->config['header_banners_directory']);
$interval = intval($this->config['header_banners_interval']);
if (empty($path) || $interval <= 0) {
return FALSE;
}
if (!utf8_validate($path) || strpos('/' . $path . '/', '/../') !== FALSE) {
logger(sprintf("%s.%s(): invalid path '%s'; bailing out", __CLASS__, __FUNCTION__, $path));
return FALSE;
}
//
// 1 -- where to find the files?
//
if (substr($path, 0, 1) == '/') {
$full_path = $CFG->datadir . $path;
} elseif (substr($path, 0, 8) == 'program/') {
$full_path = $CFG->progdir . substr($path, 7);
} else {
$full_path = $CFG->dir . '/' . $path;
}
// get rid of trailing slash if any
if (substr($full_path, -1) == '/') {
$full_path = substr($full_path, 0, -1);
}
if (($handle = @opendir($full_path)) === FALSE) {
logger(sprintf("%s.%s(): cannot open directory '%s'", __CLASS__, __FUNCTION__, $path));
return FALSE;
}
//
// 2 -- scan the directory for graphics files (skip the thumbnails)
//
$prefix_len = strlen(THUMBNAIL_PREFIX);
$extensions = explode(',', str_replace(array('.', ' '), '', $CFG->filemanager_images));
$files = array();
while (($entryname = readdir($handle)) !== FALSE) {
$full_entryname = $full_path . '/' . $entryname;
if ($entryname == '.' || $entryname == '..' || $entryname == 'index.html' || is_link($full_entryname) || !is_file($full_entryname)) {
continue;
}
// we are now fairly sure $entryname is a genuine file. check extension (if any)
if (strpos($entryname, '.') === FALSE) {
$ext = '';
} else {
$components = explode('.', $entryname);
$ext = utf8_strtolower(array_pop($components));
unset($components);
}
if (array_search($ext, $extensions) === FALSE) {
// not an image file, next please
continue;
}
if (substr($entryname, 0, $prefix_len) == THUMBNAIL_PREFIX) {
// thumbnail, next please
continue;
}
if (($image_info = @getimagesize($full_entryname)) === FALSE) {
// not an image, next please
continue;
}
$files[] = $entryname;
}
closedir($handle);
//
// 3 -- is there any image at all?
//
if (($n = sizeof($files)) <= 0) {
return FALSE;
}
if ($n == 1) {
$entryname = $files[0];
// Looks like Ford T: choice of 1
} else {
// use a different image every $interval minutes
$entryname = $files[($index + time() / (60 * $interval)) % $n];
}
if (substr($path, 0, 1) == '/') {
return was_file_url($path . '/' . $entryname, $fully_qualified);
} else {
return was_url($path . '/' . $entryname, $fully_qualified);
}
}
/** construct the necessary code to show N static images in case JavaScript is OFF
*
* this steps through the first N images of the snapshots list and prepares the
* necessary code to create and populate N static non-rotating img-tags,
* sandwiched ina noscript tag (gracefull degradation...)
*
* The following slideshow parameters are used:
* - the available width
* - the available height
* - the number N of visible images
*
* The following parameters of the first N images are used:
* - width of the image (in pixels)
* - height of the image (in pixels)
* - the url of the image file (src-attribute of the img tag)
* - title to add to the display (document title)
* Notably absent:
* - the number of seconds to display this image ;-)
*
* @param string $m code readability
* @return void
*/
function noscript_add_inline_show($m = ' ')
{
// sanity check
$w = max(16, intval($this->inline_show_width));
$h = max(16, intval($this->inline_show_height));
$n = max(1, intval($this->inline_show_visible_images));
$vx = intval($w / $n);
$vy = $h;
$index = 0;
$this->theme->add_content($m . '<noscript>');
if (($num_snapshots = sizeof($this->snapshots)) == 0) {
$this->theme->add_content($m . ' ' . t('js_no_images', $this->domain));
} else {
foreach ($this->snapshots as $i => $snapshot) {
if (++$index > $n) {
break;
}
$px = $snapshot['width'];
$py = $snapshot['height'];
$r = min($px * $vy, $py * $vx);
$key = $snapshot['key'];
$matches = array();
$showtime = $this->default_showtime;
if (preg_match('/^[0-9]*_([0-9]*)_/', $key, $matches)) {
$showtime = intval($matches[1]);
if (0 < $showtime && $showtime < 3600) {
$key = substr($snapshot['key'], strlen($matches[0]));
}
}
$attributes = array('width' => intval($r / $py), 'height' => intval($r / $px), 'title' => sprintf('%d/%d - %s (%dx%d, %s)', $index, $num_snapshots, $key, $snapshot['width'], $snapshot['height'], $snapshot['human_size']));
$src = was_file_url($snapshot['image']);
$this->theme->add_content($m . ' ' . html_img($src, $attributes));
}
}
$this->theme->add_content($m . '</noscript>');
return;
}
