tag-finder.php

// THIS SHOULD BE DONE IN C OR C++ I KNOW
function findTags($str=null) {
    if ($str==null) { return false; }
    $length = strlen($str);
    $temp = ""; $state = 0; $found = array();
    for($cnt=0;$cnt<$length;$cnt++) {
        $chr = substr($str, $cnt, 1);
        if ($chr == '<') {
            if ($state == 0) { $state = 1; }
            $temp .= $chr;
        }
        else if ($chr == '>') {
            if ($state == 1) { $state = 0; }
            $temp .= $chr;
            $found[] = strval($temp);
            $temp = "";
        }
        else {
            if ($state == 1) {
                $temp .= $chr;
            }
        }
    }
    return $found;
}

function parseTags($found=null) {
    if ($found==null || is_array($found)==false) { return false; }
    $parsed = array();
    foreach($found as $item) {
        $temp = array();
        // Clean the greater then and less than characters
        if (substr($item, 0, 1)=='<') { $item = substr($item, 1); }
        if (substr($item, -1, 1)=='>') { $item = substr($item, 0, intval(strlen($item)-1)); }
        // Determine what kind of tag it is
        if (substr($item, 0, 1)=='/' ) {
            $temp['TYPE'] = 'E';
            $item = substr($item, 1);
        }
        else if (substr($item, -1, 1)=='/') {
            $temp['TYPE'] = 'S';
            $item = substr($item, 0, intval(strlen($item)-1));
        }
        else { $temp['TYPE'] = 'B'; }
        // If the type is E skip further parsing
        if ($temp['TYPE'] == 'E') {
            $temp['TAG'] = $item;
            $parsed[] = $temp;
            continue;
        }
        // If the type is S or B there's a bit more
        if (preg_match("/=/", $item)==false) {
            $temp['TAG'] = $item;
        }
        else {
            // Define the tag
            $parts = split(" ", $item, 2);
            $temp['TAG'] = $parts[0];
            $temp['ATTR'] = array();
            // Collect up attributes
            $length = strlen($parts[1]);
            $state = 0; $temp_key = ""; $temp_val = "";
            for($cnt=0;$cnt<$length;$cnt++) {
                $chr = substr($parts[1],$cnt,1);
                if ($chr=='=') {
                    if ($state==0) { $state = 1; }
                    else { $temp_val .= $chr; }
                }
                else if ($chr=='"') {
                    if ($state==1) { $state = 2; }
                    else if ($state == 2) {
                        $temp['ATTR'][] = array('key'=>strval($temp_key),
                                                'val'=>strval($temp_val));
                        $temp_key = "";
                        $temp_val = "";
                        $state = 0;
                    }
                }
                else if ($chr==' ') {
                    if ($state == 2) {
                        $temp_val .= $chr;
                    }
                }
                else {
                    if ($state == 0) { $temp_key .= $chr; }
                    else { $temp_val .= $chr; }
                }
            }
        }
        // Add it to the main list
        $parsed[] = $temp;
    }
    return $parsed;
}

function parseHtml($html=null) {
    if ($html==null) { return false; }
    $tags = findTags($html);
    if (is_array($tags)==false) { return false; }
    return parseTags($tags);
}

function findSpecificTag($html=null, $tag=null, $type=null) {
    if ($tag==null||$html==null) { return false; }
    $tags = parseHtml($html);

    if ($tags==false) { return false; }
    $tags_filtered = array();
    if (isset($type)) { $type = strtoupper($type); }
    foreach($tags as $t) {
        if (isset($type)) { if ($type != $t['TYPE']) { continue; } }
        if ($tag != $t['TAG']) { continue; }
        $tags_filtered[] = $t;
    }
    if (count($tags_filtered) == 0) { return false; }
    return $tags_filtered;
}