Add markdown support for bold and italic

ui/src/main/java/io/xeres/ui/support/contentline/ContentEmphasis.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2023 by David Gerber - https://zapek.com
+ *
+ * This file is part of Xeres.
+ *
+ * Xeres 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.
+ *
+ * Xeres 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 Xeres.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package io.xeres.ui.support.contentline;
+
+import javafx.scene.Node;
+import javafx.scene.text.Text;
+
+import java.util.Set;
+
+public class ContentEmphasis implements Content
+{
+	public enum Style
+	{
+		BOLD,
+		ITALIC
+	}
+
+	private final Text node;
+
+	public ContentEmphasis(String text, Set<Style> style)
+	{
+		node = new Text(text);
+		var css = "";
+		if (style.contains(Style.BOLD))
+		{
+			css += "-fx-font-weight: bold;";
+		}
+		if (style.contains(Style.ITALIC))
+		{
+			css += "-fx-font-style: italic;";
+		}
+		if (!css.isEmpty())
+		{
+			node.setStyle(css);
+		}
+	}
+
+	@Override
+	public Node getNode()
+	{
+		return node;
+	}
+}

ui/src/main/java/io/xeres/ui/support/contentline/ContentUtils.java

@@ -19,8 +19,9 @@
 
 package io.xeres.ui.support.contentline;
 
+import io.xeres.ui.support.util.Range;
+
 import java.util.List;
-import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 public final class ContentUtils
@@ -43,14 +44,14 @@ public static void parseInlineUrls(String s, List<Content> contents)
 			var currentRange = new Range(matcher);
 
 			// Text before/between URLs
-			var betweenRange = currentRange.textRange(previousRange);
+			var betweenRange = currentRange.outerRange(previousRange);
 			if (betweenRange.hasRange())
 			{
-				contents.add(new ContentText(s.substring(betweenRange.start, betweenRange.end)));
+				contents.add(new ContentText(s.substring(betweenRange.start(), betweenRange.end())));
 			}
 
 			// URL
-			contents.add(new ContentUri(s.substring(currentRange.start, currentRange.end)));
+			contents.add(new ContentUri(s.substring(currentRange.start(), currentRange.end())));
 
 			previousRange = currentRange;
 		}
@@ -60,47 +61,11 @@ public static void parseInlineUrls(String s, List<Content> contents)
 			// Text if no URL at all
 			contents.add(new ContentText(s));
 		}
-		else if (previousRange.end < s.length())
+		else if (previousRange.end() < s.length())
 		{
 			// Text after the last URL
-			contents.add(new ContentText(s.substring(previousRange.end)));
+			contents.add(new ContentText(s.substring(previousRange.end())));
 		}
 	}
 
-	private static class Range
-	{
-		private final int start;
-		private final int end;
-
-		public Range(Matcher matcher)
-		{
-			start = matcher.start(1);
-			end = matcher.end();
-		}
-
-		public Range(int start, int end)
-		{
-			this.start = start;
-			this.end = end;
-		}
-
-		public boolean hasRange()
-		{
-			return end > start;
-		}
-
-		public Range textRange(Range other)
-		{
-			if (other.start > start)
-			{
-				// other is after us
-				return new Range(end, other.start);
-			}
-			else
-			{
-				// other is before us
-				return new Range(other.end, start);
-			}
-		}
-	}
 }

ui/src/main/java/io/xeres/ui/support/markdown/Markdown2Flow.java

@@ -1,18 +1,23 @@
 package io.xeres.ui.support.markdown;
 
 import com.vdurmont.emoji.EmojiParser;
-import io.xeres.ui.support.contentline.Content;
-import io.xeres.ui.support.contentline.ContentHeader;
-import io.xeres.ui.support.contentline.ContentUtils;
+import io.xeres.ui.support.contentline.*;
+import io.xeres.ui.support.util.Range;
 import io.xeres.ui.support.util.SmileyUtils;
 import javafx.scene.Node;
 
 import java.util.ArrayList;
+import java.util.EnumSet;
 import java.util.List;
 import java.util.Scanner;
+import java.util.function.Consumer;
+import java.util.regex.Pattern;
 
 public class Markdown2Flow
 {
+	private static final Pattern BOLD_PATTERN = Pattern.compile("(\\*\\*[^* ]((?!\\*\\*).)*[^* ]\\*\\*)");
+	private static final Pattern ITALIC_PATTERN = Pattern.compile("(\\*[^* ]((?!\\*).)*[^* ]\\*)");
+
 	private String input;
 	private final List<Content> content = new ArrayList<>();
 
@@ -51,7 +56,11 @@ private void parse()
 			}
 			else if (line.contains("*"))
 			{
-				processBoldAndItalic(line);
+				processPattern(BOLD_PATTERN, line,
+						lineBold -> content.add(new ContentEmphasis(lineBold, EnumSet.of(ContentEmphasis.Style.BOLD))), 2,
+						lineBold -> processPattern(ITALIC_PATTERN, lineBold,
+								lineItalic -> content.add(new ContentEmphasis(lineItalic, EnumSet.of(ContentEmphasis.Style.ITALIC))), 1,
+								lineItalic -> content.add(new ContentText(lineItalic))));
 			}
 			else
 			{
@@ -79,11 +88,45 @@ private void processHeader(String line)
 		content.add(new ContentHeader(line.substring(size).trim() + "\n", size));
 	}
 
-	private void processBoldAndItalic(String line)
+	private void processPattern(Pattern pattern, String line, Consumer<String> match, int matchStrip, Consumer<String> noMatch)
 	{
-		// we can have **hello *my* world** and also *hello **my** world*. a space after * or ** makes it fail
+		var matcher = pattern.matcher(line);
+		var previousRange = new Range(0, 0);
+
+		while (matcher.find())
+		{
+			var currentRange = new Range(matcher);
+
+			// Before/between matches
+			var betweenRange = currentRange.outerRange(previousRange);
+			if (betweenRange.hasRange())
+			{
+				noMatch.accept(line.substring(betweenRange.start(), betweenRange.end()));
+			}
+
+			// Match
+			match.accept(line.substring(currentRange.start() + matchStrip, currentRange.end() - matchStrip));
+
+			previousRange = currentRange;
+		}
+
+		if (!previousRange.hasRange())
+		{
+			// If no match at all
+			noMatch.accept(line);
+		}
+		else if (previousRange.end() < line.length())
+		{
+			// After the last match
+			noMatch.accept(line.substring(previousRange.end()));
+		}
+	}
 
-		// XXX: try bold for now
+	private enum SANITIZE_MODE
+	{
+		NORMAL, // keep text as it is
+		EMPTY_LINES, // remove useless empty lines
+		CONTINUATION_BREAK // remove line feed to make a continuation break
 	}
 
 	/**
@@ -95,34 +138,42 @@ static String sanitize(String input)
 	{
 		var lines = input.split("\n");
 		var sb = new StringBuilder();
-		var skip = 0; // XXX: use an enum or so... 0 = normal, 1 = empty lines, 2 = continuation break
+		var skip = SANITIZE_MODE.NORMAL;
 
 		for (String s : lines)
 		{
 			if (s.trim().isEmpty())
 			{
 				// One empty line is treated as a paragraph
-				if (skip != 1)
+				if (skip != SANITIZE_MODE.EMPTY_LINES)
 				{
 					sb.append("\n\n");
-					skip = 1;
+					skip = SANITIZE_MODE.EMPTY_LINES;
 				}
 			}
-			else if (s.startsWith("> "))
+			else if (s.startsWith("> ") || s.startsWith(">>"))
 			{
 				// We don't process quoted text
-				skip = 0;
+				skip = SANITIZE_MODE.NORMAL;
 				sb.append(s.stripTrailing()).append("\n");
 			}
 			else
 			{
 				// Normal break is treated as continuation
-				if (skip == 2)
+				if (skip == SANITIZE_MODE.CONTINUATION_BREAK)
 				{
-					sb.append(" ");
+					if (s.stripIndent().startsWith("- ") || s.stripIndent().startsWith("* "))
+					{
+						// Except quoted text
+						sb.append("\n");
+					}
+					else
+					{
+						sb.append(" ");
+					}
 				}
 				sb.append(s.stripTrailing());
-				skip = 2;
+				skip = SANITIZE_MODE.CONTINUATION_BREAK;
 			}
 		}
 		return sb.toString();

ui/src/main/java/io/xeres/ui/support/util/Range.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2023 by David Gerber - https://zapek.com
+ *
+ * This file is part of Xeres.
+ *
+ * Xeres 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.
+ *
+ * Xeres 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 Xeres.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package io.xeres.ui.support.util;
+
+import java.util.regex.Matcher;
+
+/**
+ * Helper class to handle ranges of text. Provide a matcher then you can find the start and end of the range but
+ * also the surrounding parts.
+ */
+public class Range
+{
+	private final int start;
+	private final int end;
+
+	public Range(Matcher matcher)
+	{
+		start = matcher.start(1);
+		end = matcher.end();
+	}
+
+	public Range(int start, int end)
+	{
+		this.start = start;
+		this.end = end;
+	}
+
+	public boolean hasRange()
+	{
+		return end > start;
+	}
+
+	public Range outerRange(Range other)
+	{
+		if (other.start > start)
+		{
+			// other is after us
+			return new Range(end, other.start);
+		}
+		else
+		{
+			// other is before us
+			return new Range(other.end, start);
+		}
+	}
+
+	public int start()
+	{
+		return start;
+	}
+
+	public int end()
+	{
+		return end;
+	}
+}