Follow w:numStyleLink in w:abstractNum

2 files changed, 24 insertions, 6 deletions

diff --git a/src/main/java/org/zwobble/mammoth/internal/docx/Numbering.java b/src/main/java/org/zwobble/mammoth/internal/docx/Numbering.java
index 0191763..90ea5c1 100644
--- a/src/main/java/org/zwobble/mammoth/internal/docx/Numbering.java
+++ b/src/main/java/org/zwobble/mammoth/internal/docx/Numbering.java
@@ -11,9 +11,11 @@ import static org.zwobble.mammoth.internal.util.Maps.map;
 public class Numbering {
     public static class AbstractNum {
         private final Map<String, NumberingLevel> levels;
+        private final Optional<String> numStyleLink;
 
-        public AbstractNum(Map<String, NumberingLevel> levels) {
+        public AbstractNum(Map<String, NumberingLevel> levels, Optional<String> numStyleLink) {
             this.levels = levels;
+            this.numStyleLink = numStyleLink;
         }
     }
 
@@ -25,23 +27,35 @@ public class Numbering {
         }
     }
 
-    public static final Numbering EMPTY = new Numbering(map(), map());
+    public static final Numbering EMPTY = new Numbering(map(), map(), Styles.EMPTY);
 
     private final Map<String, AbstractNum> abstractNums;
     private final Map<String, Num> nums;
+    private final Styles styles;
 
     public Numbering(
         Map<String, AbstractNum> abstractNums,
-        Map<String, Num> nums
+        Map<String, Num> nums,
+        Styles styles
     ) {
         this.abstractNums = abstractNums;
         this.nums = nums;
+        this.styles = styles;
     }
 
     public Optional<NumberingLevel> findLevel(String numId, String level) {
         return lookup(nums, numId)
             .flatMap(num -> num.abstractNumId)
             .flatMap(abstractNumId -> lookup(this.abstractNums, abstractNumId))
-            .flatMap(abstractNum -> lookup(abstractNum.levels, level));
+            .flatMap(abstractNum -> {
+                if (abstractNum.numStyleLink.isPresent()) {
+                    return abstractNum.numStyleLink
+                        .flatMap(numStyleLink -> styles.findNumberingStyleById(numStyleLink))
+                        .flatMap(style -> style.getNumId())
+                        .flatMap(linkedNumId -> findLevel(linkedNumId, level));
+                } else {
+                    return lookup(abstractNum.levels, level);
+                }
+            });
     }
 }
diff --git a/src/main/java/org/zwobble/mammoth/internal/docx/NumberingXml.java b/src/main/java/org/zwobble/mammoth/internal/docx/NumberingXml.java
index 6b5372f..b25ffdd 100644
--- a/src/main/java/org/zwobble/mammoth/internal/docx/NumberingXml.java
+++ b/src/main/java/org/zwobble/mammoth/internal/docx/NumberingXml.java
@@ -14,7 +14,7 @@ public class NumberingXml {
     public static Numbering readNumberingXmlElement(XmlElement element, Styles styles) {
         Map<String, Numbering.AbstractNum> abstractNums = readAbstractNums(element.findChildren("w:abstractNum"));
         Map<String, Numbering.Num> nums = readNums(element.findChildren("w:num"));
-        return new Numbering(abstractNums, nums);
+        return new Numbering(abstractNums, nums, styles);
     }
 
     private static Map<String, Numbering.AbstractNum> readAbstractNums(XmlElementList children) {
@@ -24,7 +24,11 @@ public class NumberingXml {
     private static Map.Entry<String, Numbering.AbstractNum> readAbstractNum(XmlElement element) {
         // TODO: in python-mammoth, we allow None here. Check whether that's actually possible or not
         String abstractNumId = element.getAttribute("w:abstractNumId");
-        return entry(abstractNumId, new Numbering.AbstractNum(readAbstractNumLevels(element)));
+        Numbering.AbstractNum abstractNum = new Numbering.AbstractNum(
+            readAbstractNumLevels(element),
+            element.findChildOrEmpty("w:numStyleLink").getAttributeOrNone("w:val")
+        );
+        return entry(abstractNumId, abstractNum);
     }
 
     private static Map<String, NumberingLevel> readAbstractNumLevels(XmlElement element) {