Fix up markdown rendering to be scrollable

lib/bbcode_converter.dart

@@ -1,11 +1,22 @@
 /// Utility class to convert BBCode to Markdown for RimWorld mod descriptions
+import 'dart:math' as math;
+
 class BBCodeConverter {
   /// Converts BBCode formatted text to Markdown format
   static String toMarkdown(String bbcode) {
     if (bbcode.isEmpty) return '';
     
-    // First, normalize line endings
-    String result = bbcode.replaceAll('\r\n', '\n');
+    // First, normalize line endings and escape any literal backslashes
+    String result = bbcode.replaceAll('\r\n', '\n').replaceAll('\\', '\\\\');
+    
+    // Ensure paragraphs - double newlines between paragraphs
+    // First normalize any consecutive newlines to a single one
+    result = result.replaceAll(RegExp(r'\n+'), '\n');
+    
+    // Then add empty line after each paragraph where needed
+    result = result.replaceAll('.\n', '.\n\n');
+    result = result.replaceAll('!\n', '!\n\n');
+    result = result.replaceAll('?\n', '?\n\n');
     
     // Fix unclosed tags - RimWorld descriptions often have unclosed tags
     final List<String> tagTypes = ['b', 'i', 'color', 'size', 'url', 'code', 'quote'];
@@ -42,30 +53,29 @@ class BBCodeConverter {
     // Italic
     result = result.replaceAll('[i]', '_').replaceAll('[/i]', '_');
     
-    // Headers
+    // Headers - ensure they start on their own line
     result = result.replaceAllMapped(
       RegExp(r'\[h1\](.*?)\[/h1\]', dotAll: true), 
-      (match) => '# ${match.group(1)}'
+      (match) => '\n\n# ${match.group(1)?.trim()}\n\n'
     );
     result = result.replaceAllMapped(
       RegExp(r'\[h2\](.*?)\[/h2\]', dotAll: true), 
-      (match) => '## ${match.group(1)}'
+      (match) => '\n\n## ${match.group(1)?.trim()}\n\n'
     );
     result = result.replaceAllMapped(
       RegExp(r'\[h3\](.*?)\[/h3\]', dotAll: true), 
-      (match) => '### ${match.group(1)}'
+      (match) => '\n\n### ${match.group(1)?.trim()}\n\n'
     );
     
     // Lists - handle nested lists too
     result = result.replaceAll('[list]', '\n').replaceAll('[/list]', '\n');
     
     // Handle list items - giving them proper indentation
-    int listLevel = 0;
     result = result.replaceAllMapped(
       RegExp(r'\[\*\](.*?)(?=\[\*\]|\[/list\]|$)', dotAll: true), 
       (match) {
         final content = match.group(1)?.trim() ?? '';
-        return '* $content\n'; 
+        return '\n* $content\n'; 
       }
     );
     
@@ -102,35 +112,64 @@ class BBCodeConverter {
         final tableContent = tableMatch.group(1) ?? '';
         final rows = RegExp(r'\[tr\](.*?)\[/tr\]', dotAll: true).allMatches(tableContent);
         
-        final markdownTable = StringBuffer();
+        // Only process tables that have rows
+        if (rows.isEmpty) {
+          result = result.replaceFirst(tableMatch.group(0)!, '');
+          continue;
+        }
+        
+        final markdownTable = StringBuffer('\n');
         var isFirstRow = true;
         
+        // First determine the number of columns by examining all rows
+        int maxColumns = 0;
+        for (final rowMatch in rows) {
+          final rowContent = rowMatch.group(1) ?? '';
+          final cellCount = RegExp(r'\[td\]').allMatches(rowContent).length;
+          maxColumns = math.max(maxColumns, cellCount);
+        }
+        
+        // Ensure we have at least 1 column
+        maxColumns = math.max(1, maxColumns);
+        
         for (final rowMatch in rows) {
           final rowContent = rowMatch.group(1) ?? '';
           final cells = RegExp(r'\[td\](.*?)\[/td\]', dotAll: true).allMatches(rowContent);
           
           if (cells.isEmpty) continue;
           
-          final rowBuffer = StringBuffer('|');
+          final rowBuffer = StringBuffer('| ');
           
+          int cellsAdded = 0;
           for (final cellMatch in cells) {
             final cellContent = cellMatch.group(1)?.trim() ?? '';
             // Clean up any newlines inside cell content
             final cleanCell = cellContent.replaceAll('\n', ' ').trim();
-            rowBuffer.write(' $cleanCell |');
+            rowBuffer.write('$cleanCell | ');
+            cellsAdded++;
+          }
+          
+          // Add empty cells if needed to maintain table structure
+          while (cellsAdded < maxColumns) {
+            rowBuffer.write(' | ');
+            cellsAdded++;
           }
           
           markdownTable.writeln(rowBuffer.toString());
           
           // Add header separator after first row
           if (isFirstRow) {
-            final cellCount = RegExp(r'\[td\]').allMatches(rowContent).length;
-            markdownTable.writeln('|${' --- |' * cellCount}');
+            final headerRow = StringBuffer('| ');
+            for (int i = 0; i < maxColumns; i++) {
+              headerRow.write('--- | ');
+            }
+            markdownTable.writeln(headerRow.toString());
             isFirstRow = false;
           }
         }
         
-        result = result.replaceFirst(tableMatch.group(0)!, '\n${markdownTable.toString()}\n');
+        markdownTable.write('\n');
+        result = result.replaceFirst(tableMatch.group(0)!, markdownTable.toString());
       }
     }
     
@@ -149,7 +188,7 @@ class BBCodeConverter {
       (match) {
         final content = match.group(1)?.trim() ?? '';
         if (content.isEmpty) return '';
-        return '\n> ${content.replaceAll('\n', '\n> ')}\n';
+        return '\n> ${content.replaceAll('\n', '\n> ')}\n\n';
       }
     );
     
@@ -163,12 +202,25 @@ class BBCodeConverter {
     // [h1] without closing tag is common
     result = result.replaceAllMapped(
       RegExp(r'\[h1\]([^\[]+)'), 
-      (match) => '# ${match.group(1)}\n'
+      (match) => '\n\n# ${match.group(1)?.trim()}\n\n'
     );
     
-    // Replace multiple newlines with at most two newlines
+    // Convert simple newlines to double newlines for proper markdown rendering
+    // But avoid doing this for lines that are already marked up as headings, lists, or tables
+    result = result.replaceAllMapped(
+      RegExp(r'([^\n#*>|])\n([^\n#*>|-])'),
+      (match) => '${match.group(1)}\n\n${match.group(2)}'
+    );
+    
+    // Normalize multiple spaces
+    result = result.replaceAll(RegExp(r' {2,}'), ' ');
+    
+    // Remove excessive newlines (more than 2 consecutive)
     result = result.replaceAll(RegExp(r'\n{3,}'), '\n\n');
     
+    // Ensure document starts and ends cleanly
+    result = result.trim();
+    
     return result;
   }
 }