add markdown support

Summary:
Adds support for Markdown documents

BUG: 360603

Test Plan: Open a Markdown (.md) document in Okular

Reviewers: #okular, aacid

Reviewed By: #okular, aacid

Subscribers: michaelweghorn, aacid

Tags: #okular

Differential Revision: https://phabricator.kde.org/D7382

cmake/modules/FindDiscount.cmake

@@ -0,0 +1,36 @@
+# - Find Discount
+# Find the discount markdown library.
+#
+# This module defines
+#  discount_FOUND - whether the discount library was found
+#  discount_LIBRARIES - the discount library
+#  discount_INCLUDE_DIR - the include path of the discount library
+
+# Copyright (c) 2017, Julian Wolff, <wolff@julianwolff.de>
+#
+# Redistribution and use is allowed according to the terms of the BSD license.
+# For details see the accompanying COPYING-CMAKE-SCRIPTS file.
+
+
+if (discount_INCLUDE_DIR AND discount_LIBRARIES)
+
+  # Already in cache
+  set (discount_FOUND TRUE)
+
+else (discount_INCLUDE_DIR AND discount_LIBRARIES)
+
+  find_library (discount_LIBRARIES
+    NAMES markdown libmarkdown
+  )
+
+  find_path (discount_INCLUDE_DIR
+    NAMES mkdio.h
+  )
+
+  include (FindPackageHandleStandardArgs)
+  find_package_handle_standard_args (discount DEFAULT_MSG discount_LIBRARIES discount_INCLUDE_DIR)
+
+endif (discount_INCLUDE_DIR AND discount_LIBRARIES)
+
+mark_as_advanced(discount_INCLUDE_DIR discount_LIBRARIES)
+

generators/CMakeLists.txt

@@ -89,6 +89,13 @@ set_package_properties("libqmobipocket" PROPERTIES
         TYPE RECOMMENDED
         PURPOSE "Support for Mobipocket documents in Okular.")
         
+find_package(Discount "2")
+set_package_properties("discount" PROPERTIES
+        DESCRIPTION "A library that gives you formatting functions suitable for marking down entire documents or lines of text"
+        URL "http://www.pell.portland.or.us/~orc/Code/discount/"
+        TYPE RECOMMENDED
+        PURPOSE "Support for Markdown documents in Okular.")
+
 # let's enable the generators properly configured
 
 if(Poppler_Qt5_FOUND)
@@ -140,3 +147,7 @@ add_subdirectory(txt)
 if(QMobipocket_FOUND)
   add_subdirectory(mobipocket)
 endif()
+
+if(discount_FOUND)
+  add_subdirectory(markdown)
+endif()

generators/markdown/CMakeLists.txt

@@ -0,0 +1,22 @@
+include_directories(
+   ${CMAKE_CURRENT_SOURCE_DIR}/../..
+)
+
+
+########### next target ###############
+
+set(okularGenerator_md_PART_SRCS
+  converter.cpp
+  generator_md.cpp
+)
+
+
+okular_add_generator(okularGenerator_md ${okularGenerator_md_PART_SRCS})
+
+target_link_libraries(okularGenerator_md okularcore KF5::I18n KF5::KIOCore ${discount_LIBRARIES})
+
+########### install files ###############
+install( FILES okularMd.desktop  DESTINATION  ${KDE_INSTALL_KSERVICES5DIR} )
+install( PROGRAMS okularApplication_md.desktop org.kde.mobile.okular_md.desktop  DESTINATION  ${KDE_INSTALL_APPDIR} )
+install( FILES org.kde.okular-md.metainfo.xml DESTINATION ${KDE_INSTALL_METAINFODIR} )
+

generators/markdown/Messages.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+$XGETTEXT $(find . -name "*.cpp" -o -name "*.h") -o $podir/okular_markdown.pot

generators/markdown/converter.cpp

@@ -0,0 +1,177 @@
+/***************************************************************************
+ *   Copyright (C) 2017 by Julian Wolff <wolff@julianwolff.de>             *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#include "converter.h"
+
+#include <KLocalizedString>
+
+#include <QTemporaryFile>
+#include <QTextDocument>
+#include <QTextStream>
+#include <QTextFrame>
+#include <QTextCursor>
+
+#include <core/action.h>
+
+#include "debug_md.h"
+
+extern "C" {
+#include <mkdio.h>
+}
+
+// older versions of discount might not have these flags.
+// defining them to 0 allows us to convert without them
+#ifndef MKD_FENCEDCODE 
+#define MKD_FENCEDCODE 0
+#endif
+
+#ifndef MKD_GITHUBTAGS 
+#define MKD_GITHUBTAGS 0
+#endif
+
+#ifndef MKD_AUTOLINK 
+#define MKD_AUTOLINK 0
+#endif
+    
+using namespace Markdown;
+
+Converter::Converter()
+: mTextDocument(nullptr)
+{
+}
+
+Converter::~Converter()
+{
+}
+
+QTextDocument* Converter::convert( const QString &fileName )
+{
+    FILE *markdownFile = fopen( fileName.toLocal8Bit(), "rb" );
+    mDir = QDir( fileName.left( fileName.lastIndexOf( '/' ) ) );
+    
+    MMIOT *markdownHandle = mkd_in( markdownFile, 0 );
+    
+    if ( !mkd_compile( markdownHandle, MKD_FENCEDCODE | MKD_GITHUBTAGS | MKD_AUTOLINK ) ) {
+        emit error( i18n( "Failed to compile markdown document!" ), -1 );
+        return 0;
+    }
+    
+    char *htmlDocument;
+    int size = mkd_document( markdownHandle, &htmlDocument );
+    
+    QString html = QString::fromUtf8( htmlDocument, size );
+    
+    mTextDocument = new QTextDocument;
+    mTextDocument->setPageSize( QSizeF( 980, 1307 ) );
+    mTextDocument->setHtml( html );
+    
+    mkd_cleanup( markdownHandle );
+    
+    QTextFrameFormat frameFormat;
+    frameFormat.setMargin( 45 );
+
+    QTextFrame *rootFrame = mTextDocument->rootFrame();
+    rootFrame->setFrameFormat( frameFormat );
+    
+    convertLinks();
+    convertImages();
+
+    return mTextDocument;
+}
+
+void Converter::convertLinks()
+{
+    convertLinks( mTextDocument->rootFrame() );
+}
+
+
+void Converter::convertLinks(QTextFrame * parent)
+{
+    for ( QTextFrame::iterator it = parent->begin(); !it.atEnd(); ++it ) {
+        QTextFrame *textFrame = it.currentFrame();
+        QTextBlock textBlock = it.currentBlock();
+
+        if ( textFrame ) {
+            convertLinks(textFrame);
+        }
+        else if ( textBlock.isValid() ) {
+            convertLinks(textBlock);
+        }
+    }
+}
+
+void Converter::convertLinks(QTextBlock & parent)
+{
+    for ( QTextBlock::iterator it = parent.begin(); !it.atEnd(); ++it ) {
+        QTextFragment textFragment = it.fragment();
+        if ( textFragment.isValid() ) {
+            QTextCharFormat textCharFormat = textFragment.charFormat();
+            if ( textCharFormat.isAnchor() ) {
+                Okular::BrowseAction *action = new Okular::BrowseAction( QUrl( textCharFormat.anchorHref() ) );
+                emit addAction( action, textFragment.position(), textFragment.position()+textFragment.length() );
+        
+            }
+        }
+    }
+}
+
+void Converter::convertImages()
+{
+    convertImages( mTextDocument->rootFrame() );
+}
+
+void Converter::convertImages(QTextFrame * parent)
+{
+    for ( QTextFrame::iterator it = parent->begin(); !it.atEnd(); ++it ) {
+        QTextFrame *textFrame = it.currentFrame();
+        QTextBlock textBlock = it.currentBlock();
+
+        if ( textFrame ) {
+            convertImages(textFrame);
+        }
+        else if ( textBlock.isValid() ) {
+            convertImages(textBlock);
+        }
+    }
+}
+
+void Converter::convertImages(QTextBlock & parent)
+{
+    for ( QTextBlock::iterator it = parent.begin(); !it.atEnd(); ++it ) {
+        QTextFragment textFragment = it.fragment();
+        if ( textFragment.isValid() ) {
+            QTextCharFormat textCharFormat = textFragment.charFormat();
+            if( textCharFormat.isImageFormat() ) {
+                
+                //TODO: Show images from http URIs
+                
+                QTextImageFormat format;
+                
+                format.setName( QDir::cleanPath( mDir.absoluteFilePath( textCharFormat.toImageFormat().name() ) ) );
+                const QImage img = QImage( format.name() );
+                
+                if ( img.width() > 890 ) {
+                    format.setWidth( 890 );
+                    format.setHeight( img.height() * 890. / img.width() );
+                }
+                else {
+                    format.setWidth( img.width() );
+                    format.setHeight( img.height() );
+                }
+                
+                QTextCursor cursor( mTextDocument );
+                cursor.setPosition( textFragment.position(), QTextCursor::MoveAnchor );
+                cursor.setPosition( textFragment.position() + textFragment.length(), QTextCursor::KeepAnchor );
+                cursor.removeSelectedText();
+                cursor.insertImage( format );
+    
+            }
+        }
+    }
+}

generators/markdown/converter.h

@@ -0,0 +1,47 @@
+/***************************************************************************
+ *   Copyright (C) 2017 by Julian Wolff <wolff@julianwolff.de>             *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#ifndef MARKDOWN_CONVERTER_H
+#define MARKDOWN_CONVERTER_H
+
+#include <QDir>
+
+#include <core/textdocumentgenerator.h>
+
+class QTextCursor;
+class QTextFrame;
+
+namespace Markdown {
+
+class Converter : public Okular::TextDocumentConverter
+{
+    Q_OBJECT
+
+    public:
+        Converter();
+        ~Converter();
+
+        QTextDocument *convert( const QString &fileName ) override;
+
+    private:
+        void convertLinks();
+        void convertImages();
+        
+        void convertLinks(QTextFrame *parent);
+        void convertLinks(QTextBlock& parent);
+        void convertImages(QTextFrame *parent);
+        void convertImages(QTextBlock& parent);
+        
+        QTextDocument *mTextDocument;
+        QDir mDir;
+};
+
+}
+
+#endif

generators/markdown/debug_md.h

@@ -0,0 +1,19 @@
+
+/***************************************************************************
+ *   Copyright (C) 2006 by Luigi Toscano <luigi.toscano@tiscali.it>        *
+ *   Copyright (C) 2014 by Frederik Gladhorn <gladhorn@kde.org>            *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#ifndef OKULAR_MD_DEBUG_P_H
+#define OKULAR_MD_DEBUG_P_H
+
+#include <QtCore/qloggingcategory.h>
+
+Q_DECLARE_LOGGING_CATEGORY(OkularMdDebug)
+
+#endif

generators/markdown/generator_md.cpp

@@ -0,0 +1,37 @@
+/***************************************************************************
+ *   Copyright (C) 2017 by Julian Wolff <wolff@julianwolff.de>             *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#include "generator_md.h"
+
+#include "converter.h"
+#include "debug_md.h"
+
+#include <KAboutData>
+#include <KLocalizedString>
+#include <kconfigdialog.h>
+
+OKULAR_EXPORT_PLUGIN(MarkdownGenerator, "libokularGenerator_md.json")
+
+MarkdownGenerator::MarkdownGenerator( QObject *parent, const QVariantList &args )
+    : Okular::TextDocumentGenerator( new Markdown::Converter, QStringLiteral("okular_markdown_generator_settings"), parent, args )
+{
+}
+
+void MarkdownGenerator::addPages( KConfigDialog* dlg )
+{
+    Okular::TextDocumentSettingsWidget *widget = new Okular::TextDocumentSettingsWidget();
+
+    dlg->addPage( widget, generalSettings(), i18n("Markdown"), QStringLiteral("text-markdown"), i18n("Markdown Backend Configuration") );
+}
+
+
+Q_LOGGING_CATEGORY(OkularMdDebug, "org.kde.okular.generators.md", QtWarningMsg)
+
+#include "generator_md.moc"
+

generators/markdown/generator_md.h

@@ -0,0 +1,27 @@
+/***************************************************************************
+ *   Copyright (C) 2017 by Julian Wolff <wolff@julianwolff.de>             *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#ifndef _OKULAR_GENERATOR_MD_H_
+#define _OKULAR_GENERATOR_MD_H_
+
+#include <core/textdocumentgenerator.h>
+
+class MarkdownGenerator : public Okular::TextDocumentGenerator
+{
+    Q_OBJECT
+    Q_INTERFACES( Okular::Generator )
+
+    public:
+        MarkdownGenerator( QObject *parent, const QVariantList &args );
+
+        // [INHERITED] reparse configuration
+        void addPages( KConfigDialog* dlg ) override;
+};
+
+#endif

generators/markdown/libokularGenerator_md.json

@@ -0,0 +1,26 @@
+{
+    "KPlugin": {
+        "Authors": [
+            {
+                "Email": "wolff@julianwolff.de",
+                "Name": "Julian Wolff",
+                "Name[x-test]": "xxJulian Wolffxx"
+            }
+        ],
+        "Copyright": "© 2017 Julian Wolff",
+        "Id": "okular_markdown",
+        "License": "GPL",
+        "MimeTypes": [
+            "text/markdown",
+            "text/x-markdown"
+        ],
+        "Name": "Markdown Backend",
+        "ServiceTypes": [
+            "okular/Generator"
+        ],
+        "Version": "0.1.0"
+    },
+    "X-KDE-Priority": 1,
+    "X-KDE-okularAPIVersion": 1,
+    "X-KDE-okularHasInternalSettings": true
+}

generators/markdown/okularApplication_md.desktop

@@ -0,0 +1,13 @@
+[Desktop Entry]
+MimeType=text/markdown;
+Terminal=false
+Name=Okular
+GenericName=Document Viewer
+Comment=Universal document viewer
+Exec=okular %U
+Icon=okular
+Type=Application
+InitialPreference=7
+Categories=Qt;KDE;Graphics;Viewer;
+NoDisplay=true
+X-KDE-Keywords=Markdown

generators/markdown/okularMd.desktop

@@ -0,0 +1,7 @@
+[Desktop Entry]
+Icon=okular
+Name=Okular
+X-KDE-ServiceTypes=KParts/ReadOnlyPart
+X-KDE-Library=okularpart
+Type=Service
+MimeType=text/markdown;

generators/markdown/org.kde.mobile.okular_md.desktop

@@ -0,0 +1,14 @@
+[Desktop Entry]
+MimeType=text/markdown;
+Name=Reader
+GenericName=Document viewer
+Comment=Viewer for various types of documents
+TryExec=kpackagelauncherqml -a org.kde.mobile.okular
+Exec=kpackagelauncherqml -a org.kde.mobile.okular %u
+Terminal=false
+Icon=okular
+Type=Application
+Categories=Qt;KDE;Graphics;Office;Viewer;
+InitialPreference=2
+NoDisplay=true
+X-KDE-Keywords=Markdown

generators/markdown/org.kde.okular-md.metainfo.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<component type="addon">
+  <id>org.kde.okular-md</id>
+  <extends>org.kde.okular.desktop</extends>
+  <metadata_license>CC0-1.0</metadata_license>
+  <project_license>GPL-2.0+ and GFDL-1.3</project_license>
+  <name>Markdown</name>
+  <summary>Adds support for reading Markdown documents</summary>
+  <mimetypes>
+    <mimetype>text/markdown</mimetype>
+  </mimetypes>
+  <url type="homepage">https://okular.kde.org</url>
+</component>

okular.categories

@@ -5,6 +5,7 @@ org.kde.okular.generators.ooo Okular (Generator OOo)
 org.kde.okular.generators.dvi.core Okular (Generator DVI/Core)
 org.kde.okular.generators.dvi.shell Okular (Generator DVI/Shell)
 org.kde.okular.generators.txt Okular (Generator TXT)
+org.kde.okular.generators.md Okular (Generator Markdown)
 org.kde.kio.msits kioslave (kio_msits)
 org.kde.okular.generators.fax Okular (Generator Fax)
 org.kde.okular.generators.pdf Okular (Generator PDF)