Add DxfWriter tests

.gitignore

@@ -4,6 +4,9 @@
 # Resources in build output
 bin/
 
+# Test output
+src/test/data/Results/
+
 ### Intellij ###
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 # Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839

src/main/java/ch/geowerkstatt/lk2dxf/DxfWriter.java

@@ -12,31 +12,61 @@
 import java.util.*;
 import java.util.stream.Stream;
 
+/**
+ * Writes a DXF file from INTERLIS {@link IomObject}s.
+ * @see <a href="https://help.autodesk.com/view/OARX/2024/ENU/?guid=GUID-235B22E0-A567-4CF6-92D3-38A2306D73F3">Autodesk DXF Reference</a>
+ * @see <a href="https://ezdxf.readthedocs.io/en/stable/index.html">ezdxf Documentation</a> (additional info autout DXF format)
+ */
 public final class DxfWriter implements AutoCloseable {
     private final DecimalFormat decimalFormat;
     private final Writer dxfWriter;
     private int handle = 1;
 
-    public DxfWriter(String filePath) throws IOException {
-        this(filePath, 3, Collections.emptyList());
+    /**
+     * Creates a new DXF writer.
+     * @param writer The writer to write the DXF file to.
+     * @throws IOException If an error occurs while writing the DXF file.
+     */
+    public DxfWriter(Writer writer) throws IOException {
+        this(writer, 3, Collections.emptyList(), null);
     }
 
-    public DxfWriter(String filePath, int doublePrecision, Collection<LayerMapping> layerMappings) throws IOException {
+    /**
+     * Creates a new DXF writer.
+     * @param filePath The path to the DXF file to write.
+     * @param doublePrecision The number of decimal places to write for double values.
+     * @param layerMappings The layer mappings to use.
+     * @param comment The comment at the beginning of the DXF file. May be {@code null}.
+     * @throws IOException If an error occurs while writing the DXF file.
+     */
+    public DxfWriter(String filePath, int doublePrecision, Collection<LayerMapping> layerMappings, String comment) throws IOException {
+        this(new FileWriter(filePath, StandardCharsets.UTF_8), doublePrecision, layerMappings, comment);
+    }
+
+    /**
+     * Creates a new DXF writer.
+     * @param writer The writer to write the DXF file to.
+     * @param doublePrecision The number of decimal places to write for double values.
+     * @param layerMappings The layer mappings to use.
+     * @param comment The comment at the beginning of the DXF file. May be {@code null}.
+     * @throws IOException If an error occurs while writing the DXF file.
+     */
+    public DxfWriter(Writer writer, int doublePrecision, Collection<LayerMapping> layerMappings, String comment) throws IOException {
         if (doublePrecision < 0) {
             throw new IllegalArgumentException("doublePrecision must be positive or zero.");
         }
         if (layerMappings == null) {
             throw new IllegalArgumentException("layerMappings must not be null.");
         }
 
-        dxfWriter = new FileWriter(filePath, StandardCharsets.UTF_8);
+        dxfWriter = writer;
         decimalFormat = new DecimalFormat("0." + "#".repeat(doublePrecision), new DecimalFormatSymbols(Locale.ROOT));
 
-        prepareDxfForWritingEntities(layerMappings);
+        prepareDxfForWritingEntities(layerMappings, comment);
     }
 
-    private void prepareDxfForWritingEntities(Collection<LayerMapping> layerMappings) throws IOException {
-        var layers = new TreeMap<String, ContentWriter>();
+    private void prepareDxfForWritingEntities(Collection<LayerMapping> layerMappings, String comment) throws IOException {
+        var layers = new LinkedHashMap<String, ContentWriter>(layerMappings.size());
         layers.put("0", () -> writeLayer("0", "Continuous", 0));
         for (var mapping : layerMappings) {
             layers.putIfAbsent(mapping.layer(), () -> writeLayer(mapping.layer(), mapping.linetype(), mapping.color()));
@@ -52,6 +82,9 @@ private void prepareDxfForWritingEntities(Collection<LayerMapping> layerMappings
                         .map(s -> (ContentWriter) (() -> writeBlock(s, () -> writeCircle("0", 0, 0, 0.5)))))
                 .toArray(ContentWriter[]::new);
 
+        if (comment != null) {
+            writeElement(999, comment);
+        }
         writeHeader();
         writeSection("CLASSES");
 
@@ -66,7 +99,7 @@ private void prepareDxfForWritingEntities(Collection<LayerMapping> layerMappings
                         () -> writeLineType("DashDotDot", 0.5, -0.25, 0.0, -0.25, 0.0, -0.25)),
                 () -> writeTable("LAYER", layers.values().toArray(ContentWriter[]::new)),
                 () -> writeTable("STYLE",
-                        () -> writeStyle("cadastra", "cadastra_regular.ttf")),
+                        layerMappings.stream().map(LayerMapping::font).filter(f -> !f.isBlank()).map(f -> (ContentWriter) () -> writeStyle(f, f)).toArray(ContentWriter[]::new)),
                 () -> writeTable("VIEW"),
                 () -> writeTable("UCS"),
                 () -> writeTable("APPID",
@@ -86,6 +119,10 @@ private void finishDxfAfterWritingEntities() throws IOException {
         writeElement(0, "EOF");
     }
 
+    /**
+     * Writes a LWPOLYLINE (Leightweight POLYLINE) to the DXF file. This is a 2D polyline that supports arcs, the 3rd dimension is ignored if present.
+     * @see <a href="https://help.autodesk.com/view/OARX/2024/ENU/?guid=GUID-748FC305-F3F2-4F74-825A-61F04D757A50">LWPOLYLINE (DXF Reference)</a>
+     */
     public void writeLwPolyline(String layerName, IomObject polyline) throws IOException {
         var segments = polyline.getattrobj("sequence", 0);
         var segmentCount = segments.getattrvaluecount("segment");
@@ -105,6 +142,10 @@ public void writeLwPolyline(String layerName, IomObject polyline) throws IOExcep
         writePolylinePoints(polyline, isClosed);
     }
 
+    /**
+     * Writes a HATCH to the DXF file. Arcs are supported, the 3rd dimension is ignored if present. The enclosed area is filled with a solid fill.
+     * @see <a href="https://help.autodesk.com/view/OARX/2024/ENU/?guid=GUID-C6C71CED-CE0F-4184-82A5-07AD6241F15B">HATCH (DXF Reference)</a>
+     */
     public void writeHatch(String layerName, IomObject multiSurface) throws IOException {
         writeElement(0, "HATCH");
         writeElement(5, getNextHandle());
@@ -189,6 +230,10 @@ private void writePolylinePoints(IomObject polyline, boolean isClosed) throws IO
         }
     }
 
+    /**
+     * Writes a CIRCLE to the DXF file.
+     * @see <a href="https://help.autodesk.com/view/OARX/2024/ENU/?guid=GUID-8663262B-222C-414D-B133-4A8506A27C18">CIRCLE (DXF Reference)</a>
+     */
     public void writeCircle(String layerName, double centerX, double centerY, double radius) throws IOException {
         writeElement(0, "CIRCLE");
         writeElement(5, getNextHandle());
@@ -200,6 +245,10 @@ public void writeCircle(String layerName, double centerX, double centerY, double
         writeElement(40, radius);
     }
 
+    /**
+     * Writes a INSERT to the DXF file. The predefined block symbol {@code blockName} is inserted at the specified {@code point}.
+     * @see <a href="https://help.autodesk.com/view/OARX/2024/ENU/?guid=GUID-28FA4CFB-9D5E-4880-9F11-36C97578252F">INSERT (DXF Reference)</a>
+     */
     public void writeBlockInsert(String layerName, String blockName, double rotation, IomObject point) throws IOException {
         writeElement(0, "INSERT");
         writeElement(5, getNextHandle());
@@ -209,25 +258,35 @@ public void writeBlockInsert(String layerName, String blockName, double rotation
         writeElement(2, blockName);
         writeElement(10, Double.parseDouble(point.getattrvalue("C1")));
         writeElement(20, Double.parseDouble(point.getattrvalue("C2")));
-        writeElement(50, rotation);
+        writeElement(50, convertOrientation(rotation));
     }
 
+    /**
+     * Writes a TEXT to the DXF file.
+     * @param layerName The layer name.
+     * @param textStyle The name of the STYLE entry that defines the font.
+     * @param text The text string.
+     * @param hAlignment The horizontal alignment of the text. Values from the HALIGNMENT INTERLIS enumeration.
+     * @param vAlignment The vertical alignment of the text. Values from the VALIGNMENT INTERLIS enumeration.
+     * @param orientation The rotation angle of the text.
+     * @param position The position of the text.
+     * @see <a href="https://help.autodesk.com/view/OARX/2024/ENU/?guid=GUID-62E5383D-8A14-47B4-BFC4-35824CAE8363">TEXT (DXF Reference)</a>
+     */
     public void writeText(String layerName, String textStyle, String text, String hAlignment, String vAlignment, double orientation, IomObject position) throws IOException {
-        var hAlignmentValue = switch (hAlignment) {
-            case "Right" -> 2;
-            case "Center" -> 1;
+        var hAlignmentValue = switch (hAlignment.toLowerCase(Locale.ROOT)) {
+            case "right" -> 2;
+            case "center" -> 1;
             default -> 0; // Left
         };
-        var vAlignmentValue = switch (vAlignment) {
-            case "Top", "Cap" -> 3;
-            case "Half" -> 2;
-            case "Bottom" -> 1;
+        var vAlignmentValue = switch (vAlignment.toLowerCase(Locale.ROOT)) {
+            case "top", "cap" -> 3;
+            case "half" -> 2;
+            case "bottom" -> 1;
             default -> 0; // Base
         };
         var isDefaultAlignment = hAlignmentValue == 0 && vAlignmentValue == 0;
 
-        // Convert transfer orientation to DXF orientation
-        orientation = (-orientation + 90 + 360) % 360;
+        orientation = convertOrientation(orientation);
 
         writeElement(0, "TEXT");
         writeElement(5, getNextHandle());
@@ -338,7 +397,7 @@ private void writeBlock(String name, ContentWriter... writeContent) throws IOExc
         writeElement(100, "AcDbBlockEnd");
     }
 
-    public void writeMinimalDictionary() throws IOException {
+    private void writeMinimalDictionary() throws IOException {
         var rootHandle = getNextHandle();
         var entryHandle = getNextHandle();
 
@@ -424,6 +483,13 @@ private String getNextHandle() {
         return Integer.toHexString(handle++).toUpperCase(Locale.ROOT);
     }
 
+    /**
+     * Convert transfer orientation to DXF orientation.
+     */
+    private double convertOrientation(double angle) {
+        return (-angle + 90 + 360) % 360;
+    }
+
     @Override
     public void close() throws Exception {
         finishDxfAfterWritingEntities();

src/main/java/ch/geowerkstatt/lk2dxf/Main.java

@@ -57,7 +57,7 @@ private static void processFiles(LK2DxfOptions options) {
         Optional<Geometry> perimeter = options.parsePerimeter();
         AtomicInteger counter = new AtomicInteger();
 
-        try (var dxfWriter = new DxfWriter(options.dxfFile(), 3, ObjectMapper.getLayerMappings())) {
+        try (var dxfWriter = new DxfWriter(options.dxfFile(), 3, ObjectMapper.getLayerMappings(), "lk2dxf " + Main.VERSION)) {
             for (String xtfFile : options.xtfFiles()) {
                 try (LKMapXtfReader reader = new LKMapXtfReader(new File(xtfFile))) {
                     ObjectMapper mapper = new ObjectMapper();

src/main/java/ch/geowerkstatt/lk2dxf/mapping/ObjectMapper.java

@@ -29,6 +29,9 @@ public final class ObjectMapper {
         }
     }
 
+    /**
+     * Get the layer mappings as an immutable list.
+     */
     public static List<LayerMapping> getLayerMappings() {
         return Collections.unmodifiableList(LAYER_MAPPINGS);
     }