From 8bc23cafb44d1984c9e31e2b07d07c3bca5a46c3 Mon Sep 17 00:00:00 2001
From: "physikerwelt (Moritz Schubotz)" <wiki@physikerwelt.de>
Date: Fri, 6 Jun 2014 00:12:33 +0200
Subject: [PATCH] SpecialPage for MathImages

Add new special page that displays
math images. (Either SVG- or PNG-Images)

Change-Id: I6065b474b8197232fcb4e79ae17bb08d9bef3ac4
---
 Math.alias.php           |  14 +++++
 Math.php                 |   4 ++
 SpecialMathShowImage.php | 111 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 129 insertions(+)
 create mode 100644 Math.alias.php
 create mode 100644 SpecialMathShowImage.php

diff --git a/Math.alias.php b/Math.alias.php
new file mode 100644
index 0000000..0613ed6
--- /dev/null
+++ b/Math.alias.php
@@ -0,0 +1,14 @@
+<?php
+/**
+ * Aliases for Math
+ *
+ * @file
+ * @ingroup Extensions
+ */
+
+$specialPageAliases = array();
+
+/** English (English) */
+$specialPageAliases['en'] = array(
+	'MathShowImage' => array( 'MathShowImage', 'MathShowImage' ) // No need to translate! The PageTitle does not appear.
+);
\ No newline at end of file
diff --git a/Math.php b/Math.php
index 7df3a06..b97f6a7 100644
--- a/Math.php
+++ b/Math.php
@@ -211,11 +211,15 @@ $wgAutoloadClasses['MathMathML'] = $dir . 'MathMathML.php';
 $wgAutoloadClasses['MathLaTeXML'] = $dir . 'MathLaTeXML.php';
 $wgAutoloadClasses['MathInputCheck'] = $dir . 'MathInputCheck.php';
 $wgAutoloadClasses['MathInputCheckTexvc'] = $dir . 'MathInputCheckTexvc.php';
+$wgAutoloadClasses['SpecialMathShowImage'] = $dir . 'SpecialMathShowImage.php';
 $wgMessagesDirs['Math'] = __DIR__ . '/i18n';
 $wgExtensionMessagesFiles['Math'] = $dir . 'Math.i18n.php';
+$wgExtensionMessagesFiles['MathAlias'] = $dir . 'Math.alias.php';
 
 $wgParserTestFiles[] = $dir . 'mathParserTests.txt';
 
+$wgSpecialPageGroups[ 'MathShowImage' ] = 'other';
+$wgSpecialPages['MathShowImage'] = 'SpecialMathShowImage';
 
 $wgResourceModules['ext.math.styles'] = array(
 	'localBasePath' => __DIR__ . '/modules',
diff --git a/SpecialMathShowImage.php b/SpecialMathShowImage.php
new file mode 100644
index 0000000..3d38504
--- /dev/null
+++ b/SpecialMathShowImage.php
@@ -0,0 +1,111 @@
+<?php
+/**
+ * Description of SpecialMathShowSVG
+ *
+ * @author Moritz Schubotz (Physikerwelt)
+ */
+class SpecialMathShowImage extends SpecialPage {
+	private $noRender = false;
+	private $renderer = null;
+	private $mode = false;
+
+	function __construct() {
+		parent::__construct( 'MathShowImage' );
+	}
+	/**
+	 * Sets headers - this should be called from the execute() method of all derived classes!
+	 */
+	function setHeaders( $success = true ) {
+		$out = $this->getOutput();
+		$request = $this->getRequest();
+		$out->setArticleBodyOnly( true );
+		$out->setArticleRelated( false );
+		$out->setRobotPolicy( "noindex,nofollow" );
+		$out->disable();
+		if ( $success && $this->mode == MW_MATH_PNG ) {
+			$request->response()->header( "Content-type: image/png;" );
+		} else {
+			$request->response()->header( "Content-type: image/svg+xml; charset=utf-8" );
+		}
+		if ( $success && !( $this->noRender ) ) {
+			$request->response()->header( 'Cache-Control: public max-age=2419200' ); // 4 weeks
+			$request->response()->header( 'Vary: User-Agent' );
+		}
+	}
+
+	function execute( $par ) {
+		$request = $this->getRequest();
+		$hash = $request->getText( 'hash', '' );
+		$tex = $request->getText( 'tex', '');
+		$asciimath = $request->getText( 'asciimath', '');
+		$this->mode = $request->getInt( 'mode', MW_MATH_MATHML );
+		if ( $hash === '' && $tex === '' && $asciimath === '' ) {
+			$this->setHeaders( false );
+			echo $this->printSvgError( 'No Inputhash specified' );
+		} else {
+			if ( $tex === '' && $asciimath === ''){
+				switch ( $this->mode ) {
+					case MW_MATH_PNG:
+						$this->renderer = MathTexvc::newFromMd5( $hash );
+						break;
+					case MW_MATH_LATEXML:
+						$this->renderer = MathLaTeXML::newFromMd5( $hash );
+						break;
+					default:
+						$this->renderer = MathMathML::newFromMd5( $hash );
+				}
+				$this->noRender = $request->getBool( 'noRender', false );
+				if ( $this->noRender ) {
+					$success = $this->renderer->readFromDatabase();
+				} else {
+					if ( $this->mode == MW_MATH_PNG ) {
+						$mmlRenderer = MathMathML::newFromMd5( $hash );
+						$mmlRenderer->readFromDatabase();
+						$this->renderer = new MathTexvc( $mmlRenderer->getUserInputTex() );
+					}
+					$success = $this->renderer->render();
+				}
+			} elseif ( $asciimath === '' ) {
+				$this->renderer = MathRenderer::getRenderer( $tex , array(), $this->mode );
+				$success = $this->renderer->render();
+			} else {
+				$this->renderer = MathRenderer::getRenderer( $asciimath , array( 'type' => 'ascii' ), $this->mode );
+				$success = $this->renderer->render();
+			}
+			if ( $success ) {
+				if ( $this->mode == MW_MATH_PNG ) {
+					$output = $this->renderer->getPng();
+				} else {
+					$output = $this->renderer->getSvg();
+				}
+			} else {
+				// Error message in PNG not supported
+				$output = $this->printSvgError( $this->renderer->getLastError() );
+			}
+			if ( $output == "" ) {
+				$output = $this->printSvgError( 'No Output produced' );
+				$success = false;
+			}
+			$this->setHeaders( $success );
+			echo $output;
+			$this->renderer->writeCache();
+		}
+	}
+
+	/**
+	 * Prints the specified error message as svg.
+	 * @param string $msg error message
+	 * @return xml svg image with the error message
+	 */
+	private function printSvgError( $msg ) {
+		global $wgMathDebug;
+		$result =  '<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 100 4"
+ preserveAspectRatio="xMidYMid meet" >' .
+			'<text text-anchor="start" fill="red" y="2">' . htmlspecialchars( $msg ) . '</text></svg>';
+		if ( $wgMathDebug ) {
+			$result .= '<!--'. var_export($this->renderer, true) .'-->';
+		}
+		return $result;
+	}
+
+}
\ No newline at end of file