package eu.faircode.email;
/*
This file is part of FairEmail.
FairEmail 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 3 of the License, or
(at your option) any later version.
FairEmail is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with FairEmail. If not, see .
Copyright 2018-2024 by Marcel Bokhorst (M66B)
*/
import com.vladsch.flexmark.html2md.converter.FlexmarkHtmlConverter;
import com.vladsch.flexmark.util.data.DataHolder;
import com.vladsch.flexmark.util.data.MutableDataSet;
import org.commonmark.Extension;
import org.commonmark.ext.gfm.strikethrough.StrikethroughExtension;
import org.commonmark.ext.gfm.tables.TablesExtension;
import org.commonmark.ext.ins.InsExtension;
import org.commonmark.ext.task.list.items.TaskListItemsExtension;
import org.commonmark.node.Node;
import org.commonmark.parser.Parser;
import org.commonmark.renderer.html.HtmlRenderer;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class Markdown {
static String toHtml(String markdown) {
// https://github.com/commonmark/commonmark-java#usage
// https://github.com/commonmark/commonmark-java/issues/294
markdown = markdown.replace('\u00a0', ' ');
List extensions = Arrays.asList(
InsExtension.create(),
TaskListItemsExtension.create(),
TablesExtension.create(),
StrikethroughExtension.create());
Parser p = Parser.builder()
.extensions(extensions)
.build();
Node d = p.parse(markdown);
HtmlRenderer r = HtmlRenderer.builder()
.extensions(extensions)
.build();
String html = r.render(d);
if (BuildConfig.DEBUG) {
Log.i("Markdown md=" + markdown.replace('\n', '|'));
Log.i("Markdown html=" + html.replace('\n', '|'));
}
return html;
}
static String fromHtml(String html) {
// https://github.com/vsch/flexmark-java/wiki/Extensions#html-to-markdown
Map specialCharsMap = new HashMap<>();
//specialCharsMap.put("“", "\"");
//specialCharsMap.put("”", "\"");
specialCharsMap.put("“", "\"");
specialCharsMap.put("”", "\"");
//specialCharsMap.put("‘", "'");
//specialCharsMap.put("’", "'");
specialCharsMap.put("‘", "'");
specialCharsMap.put("’", "'");
specialCharsMap.put("'", "'");
//specialCharsMap.put("«", "<<");
specialCharsMap.put("«", "<<");
//specialCharsMap.put("»", ">>");
specialCharsMap.put("»", ">>");
//specialCharsMap.put("…", "...");
specialCharsMap.put("…", "...");
//specialCharsMap.put("–", "--");
specialCharsMap.put("&endash;", "--");
//specialCharsMap.put("—", "---");
specialCharsMap.put("&emdash;", "---");
DataHolder options = new MutableDataSet()
.set(FlexmarkHtmlConverter.SETEXT_HEADINGS, false)
.set(FlexmarkHtmlConverter.OUTPUT_ATTRIBUTES_ID, false)
.set(FlexmarkHtmlConverter.TYPOGRAPHIC_REPLACEMENT_MAP, specialCharsMap)
.toImmutable();
// Remove nested/empty tables
Document doc = JsoupEx.parse(html);
for (Element table : doc.select("table")) {
boolean empty = false;
Elements children = table.children().select("table");
if (children.size() == 0)
for (Element tr : table.children()) {
if (tr.children().size() == 1) {
empty = true;
break;
}
if (empty)
break;
}
if (children.size() > 0 || empty) {
table.tagName("div");
for (Element child : table.children())
if ("tr".equals(child.tagName()))
child.tagName("div");
else if ("td".equals(child.tagName()))
child.tagName("span");
}
}
String markdown = FlexmarkHtmlConverter.builder(options)
.build()
.convert(doc.html());
if (BuildConfig.DEBUG) {
Log.i("Markdown html=" + html.replace('\n', '|'));
Log.i("Markdown md=" + markdown.replace('\n', '|'));
}
return markdown
.replaceAll("(?m)^( *)(\\d+)\\.( +)", "$1$2\\\\.$3")
.replaceAll("
", "")
.replaceAll("\n\n\\s+\n", "");
}
}