/**
* replace source object with alternatives according to user's preferences
* @access public
* @param $cid: content id.
* @param $content: the original content page ($content_row['text'], from content.php).
* @param $info_only: when "true", return the array of info (has_text_alternative, has_audio_alternative, has_visual_alternative, has_sign_lang_alternative)
* @param $only_on_secondary_type:
* @return string $content: the content page with the appropriated resources.
* @see $db from include/vitals.inc.php
* @author Cindy Qi Li
*/
public static function applyAlternatives($cid, $content, $info_only = false, $only_on_secondary_type = 0)
{
global $db, $_course_id;
include_once TR_INCLUDE_PATH . 'classes/DAO/DAO.class.php';
$dao = new DAO();
$video_exts = array("mpg", "avi", "wmv", "mov", "swf", "mp4", "flv");
$audio_exts = array("mp3", "wav", "ogg", "mid");
$audio_width = 425;
$audio_height = 27;
$txt_exts = array("txt", "html", "htm");
$image_exts = array("gif", "bmp", "png", "jpg", "jpeg", "png", "tif");
$only_on_secondary_type = intval($only_on_secondary_type);
// intialize the 4 returned values when $info_only is on
if ($info_only) {
$has_text_alternative = false;
$has_audio_alternative = false;
$has_visual_alternative = false;
$has_sign_lang_alternative = false;
}
if (!$info_only && !$only_on_secondary_type && $_SESSION['prefs']['PREF_USE_ALTERNATIVE_TO_TEXT'] == 0 && $_SESSION['prefs']['PREF_USE_ALTERNATIVE_TO_AUDIO'] == 0 && $_SESSION['prefs']['PREF_USE_ALTERNATIVE_TO_VISUAL'] == 0) {
//No user's preferences related to content format are declared
if (!$info_only) {
return $content;
} else {
return array($has_text_alternative, $has_audio_alternative, $has_visual_alternative, $has_sign_lang_alternative);
}
}
// get all relations between primary resources and their alternatives
$sql = "SELECT DISTINCT c.content_path, pr.resource, prt.type_id primary_type,\r\n sr.secondary_resource, srt.type_id secondary_type\r\n\t\t FROM " . TABLE_PREFIX . "primary_resources pr, " . TABLE_PREFIX . "primary_resources_types prt," . TABLE_PREFIX . "secondary_resources sr," . TABLE_PREFIX . "secondary_resources_types srt," . TABLE_PREFIX . "content c\r\n\t\t WHERE pr.content_id=" . $cid . "\r\n\t\t\t AND pr.primary_resource_id = prt.primary_resource_id\r\n\t\t\t AND pr.primary_resource_id = sr.primary_resource_id\r\n\t\t\t AND sr.language_code='" . $_SESSION['lang'] . "'\r\n\t\t\t AND sr.secondary_resource_id = srt.secondary_resource_id\r\n\t\t AND pr.content_id = c.content_id";
if ($only_on_secondary_type > 0) {
$sql .= " AND srt.type_id=" . $only_on_secondary_type;
}
$sql .= " ORDER BY pr.primary_resource_id, prt.type_id";
$rows = $dao->execute($sql);
if (!is_array($rows)) {
if (!$info_only) {
return $content;
} else {
return array($has_text_alternative, $has_audio_alternative, $has_visual_alternative, $has_sign_lang_alternative);
}
}
$primary_resource_names = array();
foreach ($rows as $row) {
// if the primary resource is defined with multiple resource type,
// the primary resource would be replaced/appended multiple times.
// This is what we want at applying alternatives by default, but
// not when only one secondary type is chosen to apply.
// This fix is to remove the duplicates on the same primary resource.
// A dilemma of this fix is, for example, if the primary resource type
// is "text" and "visual", but
// $_SESSION['prefs']['PREF_ALT_TO_TEXT_APPEND_OR_REPLACE'] == 'replace'
// $_SESSION['prefs']['PREF_ALT_TO_VISUAL_APPEND_OR_REPLACE'] == 'append'
// so, should replace happen or append happen? With this fix, whichever
// the first in the sql return gets preserved in the array and processed.
// The further improvement is requried to keep rows based on the selected
// secondary type (http://www.atutor.ca/atutor/mantis/view.php?id=4598).
if ($only_on_secondary_type > 0) {
if (in_array($row['resource'], $primary_resource_names)) {
continue;
} else {
$primary_resource_names[] = $row['resource'];
}
}
$alternative_rows[] = $row;
$youtube_playURL = ContentUtility::convertYoutubeWatchURLToPlayURL($row['resource']);
if ($row['resource'] != $youtube_playURL) {
$row['resource'] = $youtube_playURL;
$alternative_rows[] = $row;
}
}
foreach ($alternative_rows as $row) {
if ($info_only || $only_on_secondary_type || $_SESSION['prefs']['PREF_USE_ALTERNATIVE_TO_TEXT'] == 1 && $row['primary_type'] == 3 && ($_SESSION['prefs']['PREF_ALT_TO_TEXT'] == "audio" && $row['secondary_type'] == 1 || $_SESSION['prefs']['PREF_ALT_TO_TEXT'] == "visual" && $row['secondary_type'] == 4 || $_SESSION['prefs']['PREF_ALT_TO_TEXT'] == "sign_lang" && $row['secondary_type'] == 2) || $_SESSION['prefs']['PREF_USE_ALTERNATIVE_TO_AUDIO'] == 1 && $row['primary_type'] == 1 && ($_SESSION['prefs']['PREF_ALT_TO_AUDIO'] == "visual" && $row['secondary_type'] == 4 || $_SESSION['prefs']['PREF_ALT_TO_AUDIO'] == "text" && $row['secondary_type'] == 3 || $_SESSION['prefs']['PREF_ALT_TO_AUDIO'] == "sign_lang" && $row['secondary_type'] == 2) || $_SESSION['prefs']['PREF_USE_ALTERNATIVE_TO_VISUAL'] == 1 && $row['primary_type'] == 4 && ($_SESSION['prefs']['PREF_ALT_TO_VISUAL'] == "audio" && $row['secondary_type'] == 1 || $_SESSION['prefs']['PREF_ALT_TO_VISUAL'] == "text" && $row['secondary_type'] == 3 || $_SESSION['prefs']['PREF_ALT_TO_VISUAL'] == "sign_lang" && $row['secondary_type'] == 2)) {
$ext = substr($row['secondary_resource'], strrpos($row['secondary_resource'], '.') + 1);
// alternative is video
if (in_array($ext, $video_exts) || in_array($ext, $audio_exts) || preg_match("/http:\\/\\/.*youtube.com\\/watch.*/", $row['secondary_resource'])) {
if (in_array($ext, $audio_exts)) {
// display audio medias in a smaller width/height (425 * 27)
// A hack for now to handle audio media player size
$target = '[media|' . $audio_width . '|' . $audio_height . ']' . $row['secondary_resource'] . '[/media]';
} else {
// use default media size for video medias
$target = '[media]' . $row['secondary_resource'] . '[/media]';
}
} else {
if (in_array($ext, $txt_exts)) {
if ($row['content_path'] != '') {
$file_location = $row['content_path'] . '/' . $row['secondary_resource'];
} else {
$file_location = $row['secondary_resource'];
}
$file = TR_CONTENT_DIR . $_SESSION['course_id'] . '/' . $file_location;
$target = '<br />' . file_get_contents($file);
// check whether html file
if (preg_match('/.*\\<html.*\\<\\/html\\>.*/s', $target)) {
// is a html file, use iframe to display
// get real path to the text file
if (defined('TR_FORCE_GET_FILE') && TR_FORCE_GET_FILE) {
$course_base_href = 'get.php/';
} else {
$course_base_href = 'content/' . $_SESSION['course_id'] . '/';
}
$file = TR_BASE_HREF . $course_base_href . $file_location;
$target = '<iframe width="100%" frameborder="0" class="autoHeight" scrolling="auto" src="' . $file . '"></iframe>';
} else {
// is a text file, insert/replace into content
$target = nl2br($target);
}
} else {
if (in_array($ext, $image_exts)) {
$target = '<img border="0" alt="' . _AT('alternate_text') . '" src="' . $row['secondary_resource'] . '"/>';
} else {
$target = '<p><a href="' . $row['secondary_resource'] . '">' . $row['secondary_resource'] . '</a></p>';
}
}
}
// replace or append the target alternative to the source
if ($row['primary_type'] == 3 && $_SESSION['prefs']['PREF_ALT_TO_TEXT_APPEND_OR_REPLACE'] == 'replace' || $row['primary_type'] == 1 && $_SESSION['prefs']['PREF_ALT_TO_AUDIO_APPEND_OR_REPLACE'] == 'replace' || $row['primary_type'] == 4 && $_SESSION['prefs']['PREF_ALT_TO_VISUAL_APPEND_OR_REPLACE'] == 'replace') {
$pattern_replace_to = '${1}' . "\n" . $target . "\n" . '${3}';
} else {
$pattern_replace_to = '${1}${2}' . "<br /><br />\n" . $target . "\n" . '${3}';
}
// *** Alternative replace/append starts from here ***
$processed = false;
// one primary resource is only processed once
// append/replace target alternative to [media]source[/media]
if (!$processed && preg_match("/" . preg_quote("[media") . ".*" . preg_quote("]" . $row['resource'] . "[/media]", "/") . "/sU", $content)) {
$processed = true;
if (!$info_only) {
$content = preg_replace("/(.*)(" . preg_quote("[media") . ".*" . preg_quote("]" . $row['resource'] . "[/media]", "/") . ")(.*)/sU", $pattern_replace_to, $content);
} else {
if ($row['secondary_type'] == 1) {
$has_audio_alternative = true;
}
if ($row['secondary_type'] == 2) {
$has_sign_lang_alternative = true;
}
if ($row['secondary_type'] == 3) {
$has_text_alternative = true;
}
if ($row['secondary_type'] == 4) {
$has_visual_alternative = true;
}
}
}
// append/replace target alternative to <img ... src="source" ...></a>
if (!$processed && preg_match("/\\<img.*src=\"" . preg_quote($row['resource'], "/") . "\".*\\/\\>/sU", $content)) {
$processed = true;
if (!$info_only) {
$content = preg_replace("/(.*)(\\<img.*src=\"" . preg_quote($row['resource'], "/") . "\".*\\/\\>)(.*)/sU", $pattern_replace_to, $content);
} else {
if ($row['secondary_type'] == 1) {
$has_audio_alternative = true;
}
if ($row['secondary_type'] == 2) {
$has_sign_lang_alternative = true;
}
if ($row['secondary_type'] == 3) {
$has_text_alternative = true;
}
if ($row['secondary_type'] == 4) {
$has_visual_alternative = true;
}
}
}
// append/replace target alternative to <object ... source ...></object>
if (!$processed && preg_match("/\\<object.*" . preg_quote($row['resource'], "/") . ".*\\<\\/object\\>/sU", $content)) {
$processed = true;
if (!$info_only) {
$content = preg_replace("/(.*)(\\<object.*" . preg_quote($row['resource'], "/") . ".*\\<\\/object\\>)(.*)/sU", $pattern_replace_to, $content);
} else {
if ($row['secondary_type'] == 1) {
$has_audio_alternative = true;
}
if ($row['secondary_type'] == 2) {
$has_sign_lang_alternative = true;
}
if ($row['secondary_type'] == 3) {
$has_text_alternative = true;
}
if ($row['secondary_type'] == 4) {
$has_visual_alternative = true;
}
}
}
// append/replace target alternative to <a>...source...</a> or <a ...source...>...</a>
// skip this "if" when the source object has been processed in aboved <img> tag
if (!$processed && preg_match("/\\<a.*" . preg_quote($row['resource'], "/") . ".*\\<\\/a\\>/sU", $content)) {
$processed = true;
if (!$info_only) {
$content = preg_replace("/(.*)(\\<a.*" . preg_quote($row['resource'], "/") . ".*\\<\\/a\\>)(.*)/sU", $pattern_replace_to, $content);
} else {
if ($row['secondary_type'] == 1) {
$has_audio_alternative = true;
}
if ($row['secondary_type'] == 2) {
$has_sign_lang_alternative = true;
}
if ($row['secondary_type'] == 3) {
$has_text_alternative = true;
}
if ($row['secondary_type'] == 4) {
$has_visual_alternative = true;
}
}
}
// append/replace target alternative to <embed ... source ...>
if (!$processed && preg_match("/\\<embed.*" . preg_quote($row['resource'], "/") . ".*\\>/sU", $content)) {
$processed = true;
if (!$info_only) {
$content = preg_replace("/(.*)(\\<embed.*" . preg_quote($row['resource'], "/") . ".*\\>)(.*)/sU", $pattern_replace_to, $content);
} else {
if ($row['secondary_type'] == 1) {
$has_audio_alternative = true;
}
if ($row['secondary_type'] == 2) {
$has_sign_lang_alternative = true;
}
if ($row['secondary_type'] == 3) {
$has_text_alternative = true;
}
if ($row['secondary_type'] == 4) {
$has_visual_alternative = true;
}
}
}
}
}
if (!$info_only) {
return $content;
} else {
return array($has_text_alternative, $has_audio_alternative, $has_visual_alternative, $has_sign_lang_alternative);
}
}
