/**
* Prepares XHTML content for text difference comparison.
* @param string $content XHTML content [NO SLASHES]
* @return array Array of ouwiki_line objects
*/
function ouwiki_diff_html_to_lines($content)
{
// These functions are a pain mostly because PHP preg_* don't provide
// proper information as to the start/end position of matches. As a
// consequence there is a lot of hackery going down. At every point we
// replace things with spaces rather than getting rid, in order to store
// positions within original content.
// Get rid of all script, style, object tags (that might contain non-text
// outside tags)
$content = preg_replace_callback('^(<script .*?</script>)|(<object .*?</object>)|(<style .*?</style>)^i', create_function('$matches', 'return preg_replace("/./"," ",$matches[0]);'), $content);
// Get rid of all ` symbols as we are going to use these for a marker later.
$content = preg_replace('/[`]/', ' ', $content);
// Put line breaks on block tags. Mark each line break with ` symbol
$blocktags = array('p', 'div', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'td', 'li');
$taglist = '';
foreach ($blocktags as $blocktag) {
if ($taglist !== '') {
$taglist .= '|';
}
$taglist .= "<{$blocktag}>|<\\/{$blocktag}>";
}
$content = preg_replace_callback('/((' . $taglist . ')\\s*)+/i', create_function('$matches', 'return "`".preg_replace("/./"," ",substr($matches[0],1));'), $content);
// Now go through splitting each line
$lines = array();
$index = 1;
$pos = 0;
while ($pos < strlen($content)) {
$nextline = strpos($content, '`', $pos);
if ($nextline === false) {
// No more line breaks? Take content to end
$nextline = strlen($content);
}
$linestr = substr($content, $pos, $nextline - $pos);
$line = new ouwiki_line($linestr, $pos);
if (!$line->is_empty()) {
$lines[$index++] = $line;
}
$pos = $nextline + 1;
}
return $lines;
}
