Find main document part using _rels/.rels

1 files changed, 32 insertions, 4 deletions

diff --git a/src/main/java/org/zwobble/mammoth/internal/docx/DocumentReader.java b/src/main/java/org/zwobble/mammoth/internal/docx/DocumentReader.java
index 4ef9c37..9d1b270 100644
--- a/src/main/java/org/zwobble/mammoth/internal/docx/DocumentReader.java
+++ b/src/main/java/org/zwobble/mammoth/internal/docx/DocumentReader.java
@@ -14,7 +14,8 @@ import java.nio.file.Path;
 import java.util.List;
 import java.util.Optional;
 
-import static org.zwobble.mammoth.internal.util.Lists.list;
+import static org.zwobble.mammoth.internal.util.Lists.*;
+import static org.zwobble.mammoth.internal.util.Strings.trimLeft;
 
 public class DocumentReader {
     @FunctionalInterface
@@ -23,12 +24,15 @@ public class DocumentReader {
     }
 
     public static InternalResult<Document> readDocument(Optional<Path> path, Archive zipFile) {
+        Relationships packageRelationships = readPackageRelationships(zipFile);
+        String documentFilename = findDocumentFilename(zipFile, packageRelationships);
+
         Styles styles = readStyles(zipFile);
         Numbering numbering = readNumbering(zipFile);
         ContentTypes contentTypes = readContentTypes(zipFile);
         FileReader fileReader = new PathRelativeFileReader(path);
         BodyReaders bodyReaders = name -> {
-            Relationships relationships = readRelationships(zipFile, name);
+            Relationships relationships = readRelationshipsFor(zipFile, name);
             return new BodyXmlReader(styles, numbering, relationships, contentTypes, zipFile, fileReader);
         };
         return InternalResult.flatMap(
@@ -36,10 +40,30 @@ public class DocumentReader {
             readComments(zipFile, bodyReaders),
             (notes, comments) -> {
                 DocumentXmlReader reader = new DocumentXmlReader(bodyReaders.forName("document"), notes, comments);
-                return reader.readElement(parseOfficeXml(zipFile, "word/document.xml"));
+                return reader.readElement(parseOfficeXml(zipFile, documentFilename));
             });
     }
 
+    private static Relationships readPackageRelationships(Archive archive) {
+        return readRelationships(archive, "_rels/.rels");
+    }
+
+    private static String findDocumentFilename(Archive archive, Relationships packageRelationships) {
+        String officeDocumentType = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument";
+        List<String> targets = eagerConcat(
+            eagerMap(
+                packageRelationships.findTargetsByType(officeDocumentType),
+                target -> trimLeft(target, '/')
+            ),
+            list("word/document.xml")
+        );
+        List<String> validTargets = eagerFilter(targets, archive::exists);
+        return tryGetFirst(validTargets)
+            .orElseThrow(() -> new PassThroughException(
+                new IOException("Could not find word/document.xml in ZIP file. Are you sure this is a valid .docx file?")
+            ));
+    }
+
     private static InternalResult<List<Comment>> readComments(Archive file, BodyReaders bodyReaders) {
         return tryParseOfficeXml(file, "word/comments.xml")
             .map(new CommentXmlReader(bodyReaders.forName("comments"))::readElement)
@@ -75,8 +99,12 @@ public class DocumentReader {
             .orElse(ContentTypes.DEFAULT);
     }
 
+    private static Relationships readRelationshipsFor(Archive zipFile, String name) {
+        return readRelationships(zipFile, "word/_rels/" + name + ".xml.rels");
+    }
+
     private static Relationships readRelationships(Archive zipFile, String name) {
-        return tryParseOfficeXml(zipFile, "word/_rels/" + name + ".xml.rels")
+        return tryParseOfficeXml(zipFile, name)
             .map(RelationshipsXml::readRelationshipsXmlElement)
             .orElse(Relationships.EMPTY);
     }