Pdf/Charts: add initial chart support to PDFs

Problem: TCPDF had SVG support, dompdf hasn't. This patch adds a
first rudimentary PNG conversion and a sample implementation making
use of such.

library/Icinga/Application/webrouter.php

@@ -87,6 +87,17 @@ if (in_array($path, $special)) {
     $pie->initFromRequest();
     echo $pie->render();
 
+} elseif ($path === 'png/chart.php') {
+    if (!array_key_exists('data', $_GET)) {
+        return false;
+    }
+    include __DIR__ . '/EmbeddedWeb.php';
+    EmbeddedWeb::start();
+    header('Content-Type: image/png');
+    $pie = new PieChart();
+    $pie->initFromRequest();
+    $pie->toPng();
+
 } elseif (file_exists($baseDir . '/' . $path) && is_file($baseDir . '/' . $path)) {
     return false;
 } else {

library/Icinga/Chart/Inline/PieChart.php

@@ -31,12 +31,14 @@
 namespace Icinga\Chart\Inline;
 
 use Icinga\Chart\PieChart as PieChartRenderer;
+use Imagick;
+use Exception;
 
 /**
  * Draw an inline pie-chart directly from the available request parameters.
  */
 class PieChart extends Inline {
-    public function render()
+    public function render($output = true)
     {
         $pie = new PieChartRenderer();
         $pie->disableLegend();
@@ -44,6 +46,23 @@ class PieChart extends Inline {
             'data' => $this->data, 'colors' => $this->colors, 'labels' => $this->labels
         ));
         $pie->setWidth($this->width)->setHeight($this->height);
+        if ($output) {
             echo $pie->render();
+        } else {
+            return $pie->render();
+        }
+    }
+
+    public function toPng()
+    {
+		if (! class_exists('Imagick')) {
+            // TODO: This is quick & dirty. 404?
+            throw new Exception('Cannot render PNGs without Imagick');
+        }
+        $image = new Imagick();
+        $image->readImageBlob($this->render(false));
+        $image->setImageFormat('png24');
+        $image->resizeImage($this->width, $this->height, imagick::FILTER_LANCZOS, 1);
+        echo $image;
     }
 }

library/Icinga/File/Pdf.php

@@ -48,6 +48,7 @@ class Pdf extends DOMPDF
         $html = $layout->render();
         $imgDir = Url::fromPath('img');
         $html = preg_replace('~src="' . $imgDir . '/~', 'src="' . Icinga::app()->getBootstrapDirecory() . '/img/', $html);
+        $html = preg_replace('~src="/svg/chart.php(.*)"~', 'class="icon" src="http://master1.com/png/chart.php$1"', $html);
         $this->load_html($html);
         $this->render();
         $this->stream(

library/vendor/dompdf/dompdf_config.inc.php

@@ -266,7 +266,7 @@ def("DOMPDF_ENABLE_PHP", false);
  *
  * @var bool
  */
-def("DOMPDF_ENABLE_JAVASCRIPT", true);
+def("DOMPDF_ENABLE_JAVASCRIPT", false;
 
 /**
  * Enable remote file access
@@ -285,7 +285,7 @@ def("DOMPDF_ENABLE_JAVASCRIPT", true);
  *
  * @var bool
  */
-def("DOMPDF_ENABLE_REMOTE", false);
+def("DOMPDF_ENABLE_REMOTE", true);
 
 /**
  * The debug output log