function smd_qr_code($atts, $thing=NULL) {
	extract(lAtts(array(
		'type'    => 'text', // text/link/bookmark/sms/phone/email/contact/geo/wifi
		'data'    => 'Hello world!',
		'delim'   => '|',
		'format'  => 'view', // view/download/raw
		'width'   => '200',
		'height'  => '200',
		'quality' => 'L', // L/M/Q/H
		'margin'  => '4',
		'bgcol'   => '',
		'alpha'   => '',
		'escape'  => '',
		'class'   => '',
		'html_id' => '',
		'wraptag' => '',
		'debug'   => 0,
	),$atts));

	// Common regexes
	$re_url = '@^[http://|https://|ftp://].*@';
	$re_email = "<^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$>";
	$re_phone = '/^[0-9()\-+ ]+$/';
	$re_msg = '/^.+$/';
	$re_geo = '/^[0-9.\-]+$/';
	$re_digits = '/^[0-9\+\-]+$/';

	// Each entry links the 'type' attribute with an array of:
	//  method name to call via $qrc->$method()
	//  expected params array and their format regex
	//TODO: iappli ("app")
	$allowed_types = array(
		'text' => array('text' => array('text' => $re_msg)),
		'link' => array('link' => array('url' => $re_url)),
		'bookmark' => array('bookmark' => array('title' => $re_msg, 'url' => $re_url)),
		'sms' => array('sms' => array('phone' => $re_phone, 'text' => $re_msg)),
		'phone' => array('phone_number' => array('phone' => $re_phone)),
		'contact' => array('contact_info' => array('name' => $re_msg, 'address' => $re_msg, 'phone' => $re_phone, 'email' => $re_email)),
		'email' => array('email' => array('email' => $re_email, 'subject' => $re_msg, 'message' => $re_msg)),
		'geo' => array('geo' => array('lat' => $re_geo, 'lon' => $re_geo, 'height' => $re_digits)),
		'wifi' => array('wifi' => array('type' => '^[WEP|WPA]$', 'ssid' => $re_msg, 'pass' => $re_msg)),
	);

	if (array_key_exists($type, $allowed_types)) {
		$qrc = new smd_qrcode($width, $height, $quality, $margin, $bgcol, $alpha, $escape);

		$entry = $allowed_types[$type];
		// Only ever one "entry" but it's the simplest way to split key=>value
		foreach ($entry as $method => $attribs) {
			$params = smd_qrcode_extract($attribs, $data, $delim, $method, $debug);
		}

		if ($params === false) {
			return '';
		} else {
			// Run the function that prepares the data object
			$qrc->$method($params);
		}

		if ($format == 'view') {
			$tribs = '';
			if (!$wraptag) {
				$tribs .= ($class) ? ' class="'.$class.'"' : '';
				$tribs .= ($html_id) ? ' id="'.$html_id.'"' : '';
			}

			$content = '<img src="' . $qrc->get_link() . '"'.$tribs.' alt="QR code" />';

			return ($wraptag) ? doTag($content, $wraptag, $class, '', $html_id) : $content;

		} elseif ($format == 'download') {
			$file = $qrc->get_image();
			$qrc->download_image($file);
			return '';
		} elseif ($format == 'raw') {
			$content = $qrc->get_link();
			return ($wraptag) ? doTag($content, $wraptag, $class, '', $html_id) : $content;
		}
	} else {
		trigger_error(smd_qr_code_gTxt('smd_qr_code_invalid_type', array('{type}' => $type)), E_USER_NOTICE);
		return '';
	}
}

//------------------------
function smd_qrcode_extract($permitted, $data, $dlm, $tag, $debug=false) {
	$opts = do_list($data, $dlm);

	$out = array();
	$count = 0;

	if ($debug) {
		echo '++ PERMITTED ITEMS / SUPPLIED ITEMS ++';
		dmp($permitted, $opts);
	}

	if (count($permitted) != count($opts)) {
		trigger_error(smd_qr_code_gTxt('smd_qr_code_attribute_mismatch', array('{type}' => $tag, '{count}' => count($opts), '{expected}' => count($permitted))), E_USER_NOTICE);
		return false;
	}

	foreach ($permitted as $idx => $vars) {
		if (isset($opts[$count])) {
			$dataval = $opts[$count];
			if (preg_match($vars, $dataval)) {
				$out[$idx] = $dataval;
			} else {
				trigger_error(smd_qr_code_gTxt('smd_qr_code_invalid_attribute', array('{attrib}' => $idx, '{tag}' => $tag)), E_USER_NOTICE);
				return false;
			}
		} else {
			// TODO: erm...?
		}
		$count++;
	}

	return $out;
}

function smd_qr_code_gTxt($what, $atts = array()) {
	$lang = array(
		'smd_qr_code_attribute_mismatch' => "Number of parameters don't match in '{type}' QR code: given {count}, expecting {expected}",
		'smd_qr_code_invalid_attribute' => "Invalid attribute '{attrib}' supplied in '{tag}' QR code. Check the format and order of data items",
		'smd_qr_code_invalid_type' => "Invalid QR code type '{type}'",
	);
	return strtr($lang[$what], $atts);
}

/**************************************************************************************
 * This script is developed by Arturs Sosins aka ar2rsawseen, http://code-snippets.co.cc
 * Feel free to distribute and modify code, but keep reference to its creator
 *
 * Class name prefixed with smd_ for use in Textpattern (to avoid namespace clashes)
 * Modified by Stef Dawson for Textpattern
 *
 * This class generate QR [Quick Response] codes with proper metadata for mobile  phones
 * using google chart api http://chart.apis.google.com
 * Here are sources with free QR code reading software for mobile phones:
 * http://reader.kaywa.com/
 * http://www.quickmark.com.tw/En/basic/download.asp
 * http://code.google.com/p/zxing/
 *
 * For more information, examples and online documentation visit:
 * http://code-snippets.co.cc/PHP-classes/QR-code-generator-class
 ***************************************************************************************/
class smd_qrcode
{
	private $api = 'http://chart.apis.google.com/chart';
	private $data;
	private $dimensions = '';
	private $quality = '';
	private $colour = '';
	private $escape = '';

	// Constructor
	public function smd_qrcode($width, $height, $qual, $margin, $bgcol, $alpha, $esc) {
		$this->escape = $esc;

		// Build API strings
		$w = (is_numeric($width)) ? $width : 200;
		$h = (is_numeric($height)) ? $height : 200;
		$this->dimensions = $w.'x'.$h;

		$colours = array();
		if ($alpha) $colours[] = 'a,s,000000'.substr($alpha, -2);
		if ($bgcol) $colours[] = 'bg,s,'.$bgcol;
		$this->colour = ($colours) ? join('|', $colours) : '';

		$qual = strtoupper($qual);
		$szopts[] = ($qual && in_array($qual, array('L', 'M', 'Q', 'H'))) ? $qual : 'L';
		if (is_numeric($margin)) $szopts[] = $margin;
		$this->quality = join('|', $szopts);
	}

	// create code with link metadata
	public function link($args) {
		extract($args);
		if (preg_match('/^http:\/\//', $url) || preg_match('/^https:\/\//', $url)) {
			$this->data = $url;
		} else {
			$this->data = "http://".$url;
		}
	}

	// create code with bookmark metadata
	public function bookmark($args) {
		extract($args);
		$this->data = "MEBKM:TITLE:".$title.";URL:".$url.";;";
	}

	// create text qr code
	public function text($args) {
		extract($args);
		$this->data = $text;
	}

	// create code with sms metadata
	public function sms($args) {
		extract($args);
		$this->data = "SMSTO:".$phone.":".$text;
	}

	// create code with phone number
	public function phone_number($args) {
		extract($args);
		$this->data = "TEL:".$phone;
	}

	// create code with mecard metadata
	public function contact_info($args) {
		extract($args);
		$this->data = "MECARD:N:".$name.";ADR:".$address.";TEL:".$phone.";EMAIL:".$email.";;";
	}

	// create code wth email metadata
	public function email($args) {
		extract($args);
		$this->data = "MATMSG:TO:".$email.";SUB:".$subject.";BODY:".$message.";;";
	}

	// create code with geo location metadata
	public function geo($args) {
		extract($args);
		$this->data = "GEO:".$lat.",".$lon.",".$height;
	}

	// create code with wifi configuration metadata
	public function wifi($args) {
		extract($args);
		$this->data = "WIFI:T:".$type.";S".$ssid.";".$pass.";;";
	}

	// TODO
	// create code with i-appli activating meta data
	public function iappli($adf, $cmd, $param) {
		$param_str = "";
		foreach($param as $val)
		{
			$param_str .= "PARAM:".$val["name"].",".$val["value"].";";
		}
		$this->data = "LAPL:ADFURL:".$adf.";CMD:".$cmd.";".$param_str.";";
	}

	// create code with gif or jpg image, or smf or MFi of ToruCa files as content
	public function content($args) {
		extract($args);
		$this->data = "CNTS:TYPE:".$type.";LNG:".$size.";BODY:".$content.";;";
	}

	private function get_url_params() {
		$params = array(
			'cht' => 'qr',
			'chs' => $this->dimensions,
			'chld' => $this->quality,
			'chl' => (($this->escape == 'html') ? urlencode($this->data) : $this->data),
		);

		// Colour is optional
		if ($this->colour) {
			$params['chf'] = $this->colour;
		}

		return http_build_query($params, '', '&amp;');
	}

	// get image
	public function get_image(){
		$ch = curl_init();
		curl_setopt($ch, CURLOPT_URL, $this->api);
		curl_setopt($ch, CURLOPT_POST, true);
		curl_setopt($ch, CURLOPT_POSTFIELDS, $this->get_url_params());
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
		curl_setopt($ch, CURLOPT_HEADER, false);
		curl_setopt($ch, CURLOPT_TIMEOUT, 30);

		$response = curl_exec($ch);
		curl_close($ch);
		return $response;
	}

	// get link for image
	public function get_link($follow=false){
		return $this->api.'?'.$this->get_url_params();
	}

	// force image download
	public function download_image($file){
		header('Content-Description: File Transfer');
		header('Content-Type: image/png');
		header('Content-Disposition: attachment; filename=qr_code.png');
		header('Content-Transfer-Encoding: binary');
		header('Expires: 0');
		header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
		header('Pragma: public');
		header('Content-Length: ' . filesize($file));
		ob_clean();
		flush();
		echo $file;
	}
}