Add support for code appendices: enable code blocks with language labels, line-number gutter, and directive-based integration.

.idea/workspace.xml

@@ -4,14 +4,10 @@
     <option name="autoReloadType" value="ALL" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="c64f46d5-641a-468c-8fc1-94edec1f2deb" name="Changes" comment="Refactor PDF content rendering: improve list indentation logic, add numbered code block rendering with gutter, and update text wrapping alignment.">
+    <list default="true" id="c64f46d5-641a-468c-8fc1-94edec1f2deb" name="Changes" comment="Update MarkdownToIHKChemnitz: modify core functionality for improved PDF rendering">
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/MarkdownToIHKChemnits" beforeDir="false" afterPath="$PROJECT_DIR$/MarkdownToIHKChemnits" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/diagram.go" beforeDir="false" afterPath="$PROJECT_DIR$/diagram.go" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/main.go" beforeDir="false" afterPath="$PROJECT_DIR$/main.go" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/markdown_parser.go" beforeDir="false" afterPath="$PROJECT_DIR$/markdown_parser.go" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/pdf_content.go" beforeDir="false" afterPath="$PROJECT_DIR$/pdf_content.go" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/pdf_pages.go" beforeDir="false" afterPath="$PROJECT_DIR$/pdf_pages.go" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/pdf_renderer.go" beforeDir="false" afterPath="$PROJECT_DIR$/pdf_renderer.go" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/projektarbeit.pdf" beforeDir="false" afterPath="$PROJECT_DIR$/projektarbeit.pdf" afterDir="false" />
@@ -23,7 +19,7 @@
     <option name="LAST_RESOLUTION" value="IGNORE" />
   </component>
   <component name="EmbeddingIndexingInfo">
-    <option name="cachedIndexableFilesCount" value="22" />
+    <option name="cachedIndexableFilesCount" value="23" />
     <option name="fileBasedEmbeddingIndicesEnabled" value="true" />
   </component>
   <component name="GOROOT" url="file:///usr/lib/go" />
@@ -103,7 +99,10 @@
     <MESSAGE value="Remove outdated `toc_pages.txt`, add new Go modules for IHK Chemnitz PDF rendering including diagrams, tables, and TOC functionality." />
     <MESSAGE value="Refactor PDF content rendering: improve list indentation logic, add numbered code block rendering with gutter, and update text wrapping alignment." />
     <MESSAGE value="Add table annex handling, update diagram rendering with configurable Kroki URL, and improve Markdown directive parsing" />
-    <option name="LAST_COMMIT_MESSAGE" value="Add table annex handling, update diagram rendering with configurable Kroki URL, and improve Markdown directive parsing" />
+    <MESSAGE value="Add new features: diagram rendering via Kroki, table handling improvements including appendices, and Docker Compose setup for self-hosted Kroki." />
+    <MESSAGE value="Add support for appendices: landscape diagrams, tables, and images; implement Kroki URL configurability; enhance directive parsing logic." />
+    <MESSAGE value="Update MarkdownToIHKChemnitz: modify core functionality for improved PDF rendering" />
+    <option name="LAST_COMMIT_MESSAGE" value="Update MarkdownToIHKChemnitz: modify core functionality for improved PDF rendering" />
   </component>
   <component name="XDebuggerManager">
     <breakpoint-manager>

markdown_parser.go

@@ -44,15 +44,17 @@ func ParseMarkdown(mdPath string) (Config, ast.Node, []byte, error) {
 
 // parserState tracks transient state during the AST walk.
 type parserState struct {
-	nextCodeIsAppendix    bool
+	nextCodeIsAppendix     bool
-	nextAppendixLandscape bool // set by @AnhangUMLQuer: — landscape for diagram appendix
+	nextAppendixLandscape  bool // set by @AnhangUMLQuer: — landscape for diagram appendix
-	appendixTitle         string
+	appendixTitle          string
-	nextTableCaption      string      // set by @Tabelle: directive
+	nextCodeBlockAppendix  bool // set by @AnhangCode: — next non-diagram code block → appendix
-	nextTableIsAppendix   bool        // set by @TabelleAnhang: or @TabelleAnhangQuer:
+	codeBlockAppendixTitle string
-	nextTableIsLandscape  bool        // set by @TabelleAnhangQuer:
+	nextTableCaption       string      // set by @Tabelle: directive
-	nextDiagramLandscape  bool        // set by @DiagrammQuer: directive
+	nextTableIsAppendix    bool        // set by @TabelleAnhang: or @TabelleAnhangQuer:
-	nextDiagramCaption    string      // caption for the landscape diagram page
+	nextTableIsLandscape   bool        // set by @TabelleAnhangQuer:
-	listStack             []listFrame // stack for nested list tracking
+	nextDiagramLandscape   bool        // set by @DiagrammQuer: directive
+	nextDiagramCaption     string      // caption for the landscape diagram page
+	listStack              []listFrame // stack for nested list tracking
 }
 
 // listFrame tracks the type and item counter for one list nesting level.
@@ -142,6 +144,12 @@ func RenderAST(doc ast.Node, content []byte, r *IHKRenderer) error {
 				}
 				// Fall through: render as plain code block on error
 			}
+			if state.nextCodeBlockAppendix {
+				r.AddCodeAppendix(state.codeBlockAppendixTitle, lang, code)
+				state.nextCodeBlockAppendix = false
+				state.codeBlockAppendixTitle = ""
+				return ast.WalkSkipChildren, nil
+			}
 			// Render as a numbered code block (gutter + monospace body).
 			r.RenderCodeBlock(lang, code)
 			return ast.WalkSkipChildren, nil
@@ -264,6 +272,10 @@ func handleDirectives(text string, state *parserState, r *IHKRenderer) bool {
 		case strings.HasPrefix(line, "@Quelle:"):
 			r.AddSource(strings.TrimSpace(strings.TrimPrefix(line, "@Quelle:")))
 			handled = true
+		case strings.HasPrefix(line, "@AnhangCode:"):
+			state.nextCodeBlockAppendix = true
+			state.codeBlockAppendixTitle = strings.TrimSpace(strings.TrimPrefix(line, "@AnhangCode:"))
+			handled = true
 		case strings.HasPrefix(line, "@Anhang:"):
 			r.AddAppendix(strings.TrimSpace(strings.TrimPrefix(line, "@Anhang:")))
 			handled = true

pdf_pages.go

@@ -171,8 +171,9 @@ func (r *IHKRenderer) RenderAppendices() {
 		case AppendixKindImage:
 			r.renderAppendixImage(app.Path)
 		case AppendixKindTable:
-			// Render without numbering/recording; the annex header already identifies the table.
 			r.renderTableBody(app.TableData, "")
+		case AppendixKindCode:
+			r.RenderCodeBlock(app.Lang, app.Code)
 		}
 
 		if app.Landscape {

pdf_renderer.go

@@ -38,10 +38,8 @@ const (
 	dinSpaceAfterHeading   = dinLineHtBody     // ≈ 6.35 mm
 	dinSpaceAfterParagraph = 4.0               // between body paragraphs
 
-	// List items use tighter line spacing than body text (1.2× instead of 1.5×).
+	dinLineHtList     = dinLineHtBody // 1.5× IHK standard, same as body text
-	// This keeps lists compact while remaining legible at 12 pt.
+	dinSpaceAfterList = 3.0           // gap inserted after the outermost list exits
-	dinLineHtList     = 5.0 // 12 pt × 1.2 ≈ 5.08 mm, rounded to 5.0
-	dinSpaceAfterList = 3.0 // gap inserted after the outermost list exits
 )
 
 // AppendixKind distinguishes between image and table annexes.
@@ -50,6 +48,7 @@ type AppendixKind int
 const (
 	AppendixKindImage AppendixKind = iota
 	AppendixKindTable
+	AppendixKindCode
 )
 
 // Appendix holds the content for one annex entry.
@@ -59,6 +58,8 @@ type Appendix struct {
 	Title     string
 	Path      string     // image path (Kind == AppendixKindImage)
 	TableData [][]string // table rows (Kind == AppendixKindTable)
+	Lang      string     // language label (Kind == AppendixKindCode)
+	Code      string     // source code (Kind == AppendixKindCode)
 }
 
 // IHKRenderer is the central PDF generator for IHK Chemnitz project documentation.
@@ -183,6 +184,16 @@ func (r *IHKRenderer) AddTableAppendix(title string, data [][]string) {
 	})
 }
 
+// AddCodeAppendix registers a source-code annex rendered with line-number gutter.
+func (r *IHKRenderer) AddCodeAppendix(title, lang, code string) {
+	r.appendices = append(r.appendices, Appendix{
+		Kind:  AppendixKindCode,
+		Title: title,
+		Lang:  lang,
+		Code:  code,
+	})
+}
+
 // AddLandscapeAppendix registers an image annex in "Title | /path/to/image" format
 // that will be rendered on a landscape A4 page with 15 mm symmetric margins.
 func (r *IHKRenderer) AddLandscapeAppendix(titlePath string) {

report.md

@@ -282,6 +282,38 @@ eine konfigurierbare Spaltenbreite für Tabellen umfassen.
 | Bildanhang | @Anhang: Titel \| Pfad | Fügt ein Bild als nummerierte Anlage in den Anhang ein |
 | Diagrammanhang | @AnhangUML: Titel | Rendert den folgenden Mermaid/PlantUML-Block als Anlage |
 
+@AnhangCode: Implementierung – Tabellen-Renderer (prepareRow)
+
+```go
+func (r *IHKRenderer) prepareRow(rawCells []string, numCols int,
+    colW, lineHt float64, bold bool) tableRowData {
+
+    r.pdf.SetFont("Helvetica", map[bool]string{true: "B", false: ""}[bold], dinFontCaption)
+
+    cells := make([][]string, numCols)
+    maxLines := 0
+    for j := 0; j < numCols; j++ {
+        raw := ""
+        if j < len(rawCells) {
+            raw = rawCells[j]
+        }
+        split := r.pdf.SplitLines([]byte(r.tr(raw)), colW-2)
+        lines := make([]string, len(split))
+        for k, b := range split {
+            lines[k] = string(b)
+        }
+        if len(lines) == 0 {
+            lines = []string{""}
+        }
+        cells[j] = lines
+        if len(lines) > maxLines {
+            maxLines = len(lines)
+        }
+    }
+    return tableRowData{cells: cells, height: float64(maxLines) * lineHt}
+}
+```
+
 @AnhangUML: Systemarchitektur – Datenflussdiagramm
 
 ```mermaid