<?php
// Based on: https://github.com/Zverik/mbtiles-php
// Read: https://github.com/klokantech/tileserver-php/issues/1
// TODO: clean the code!!!

if (!is_file($_GET['tileset'])) {
  header('HTTP/1.0 404 Not Found');
  echo "<h1>404 Not Found</h1>";
  echo "TileServer.php could not found what you requested.";
  die();
  // TODO: if ($_GET['ext'] == 'png') { ...
  // TODO: better image 256x256px !!!
  // header("Content-type: image/png");
//print("\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\x01\x00\x00\x00\x01\x08\x06\x00\x00\x00\x1f\x15\xc4\x89\x00\x00\x00\rIDAT\x08\xd7c````\x00\x00\x00\x05\x00\x01^\xf3*:\x00\x00\x00\x00IEND\xaeB`\x82");
}

if( isset($_GET['tileset']) ) {
	$tileset = $_GET['tileset'];
	$flip = true;
	try {
		$db = new PDO('sqlite:'.$tileset,'','',array(PDO::ATTR_PERSISTENT => true));
		if( !isset($db) ) {
			header('Content-type: text/plain');
			print 'Incorrect tileset name: '.$_GET['tileset'];
			exit;
		}
		// http://c.tile.openstreetmap.org/12/2392/1190.png
		$z = floatval($_GET['z']);
		$y = floatval($_GET['y']);
		$x = floatval($_GET['x']);
		if( $flip ) {
			$y = pow(2, $z) - 1 - $y;
		}
		$result = $db->query('select tile_data as t from tiles where zoom_level='.$z.' and tile_column='.$x.' and tile_row='.$y);
		$data = $result->fetchColumn();
		if( !isset($data) || $data === FALSE ) {
		  // TODO: Put here ready to use empty tile!!!
			$png = imagecreatetruecolor(256, 256);
			imagesavealpha($png, true);
			$trans_colour = imagecolorallocatealpha($png, 0, 0, 0, 127);
			imagefill($png, 0, 0, $trans_colour);
			header('Content-type: image/png');
			imagepng($png);
			//header($_SERVER['SERVER_PROTOCOL'].' 404 Not Found');
		} else {
			$result = $db->query('select value from metadata where name="format"');
			$resultdata = $result->fetchColumn();
			$format = isset($resultdata) && $resultdata !== FALSE ? $resultdata : 'png';
			if( $format == 'jpg' )
				$format = 'jpeg';
			header('Content-type: image/'.$format);
			print $data;
		}
	} catch( PDOException $e ) {
		header('Content-type: text/plain');
		print 'Error querying the database: '.$e->getMessage();
	}
}
/*
function getbaseurl() {
	return 'http://'.$_SERVER['HTTP_HOST'].preg_replace('/\/(1.0.0\/)?[^\/]*$/','/',$_SERVER['REQUEST_URI']);
}
*/
function readparams( $db ) {
	$params = array();
	$result = $db->query('select name, value from metadata');
	while ($row = $result->fetch(PDO::FETCH_ASSOC)) {
		$params[$row['name']] = $row['value'];
	}
	return $params;
}

function readzooms( $db ) {
	$zooms = array();
	$result = $db->query('select zoom_level from tiles group by zoom_level order by zoom_level');
	while ($zoom = $result->fetchColumn()) {
		$zooms[] = $zoom;
	}
	return $zooms;
}
?>