Find comments part using document relationships

2 files changed, 63 insertions, 16 deletions

diff --git a/lib/docx/docx-reader.js b/lib/docx/docx-reader.js
index cbeaccd..e6dd798 100644
--- a/lib/docx/docx-reader.js
+++ b/lib/docx/docx-reader.js
@@ -83,29 +83,64 @@ function read(docxFile, input) {
 
 function findPartPaths(docxFile) {
     return readPackageRelationships(docxFile).then(function(packageRelationships) {
-        var documentFilename = findDocumentFilename(docxFile, packageRelationships);
-        return {
-            mainDocument: documentFilename,
-            comments: "word/comments.xml",
-            endnotes: "word/endnotes.xml",
-            footnotes: "word/footnotes.xml",
-            numbering: "word/numbering.xml",
-            styles: "word/styles.xml"
-        };
+        var mainDocumentPath = findPartPath({
+            docxFile: docxFile,
+            relationships: packageRelationships,
+            relationshipType: "http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument",
+            basePath: "",
+            fallbackPath: "word/document.xml"
+        });
+        
+        if (!docxFile.exists(mainDocumentPath)) {
+            throw new Error("Could not find main document part. Are you sure this is a valid .docx file?");
+        }
+        
+        return xmlFileReader({
+            filename: relationshipsFilename(mainDocumentPath),
+            readElement: relationshipsReader.readRelationships,
+            defaultValue: relationshipsReader.defaultValue
+        })(docxFile).then(function(documentRelationships) {
+            function findPartRelatedToMainDocument(options) {
+                return findPartPath({
+                    docxFile: docxFile,
+                    relationships: documentRelationships,
+                    relationshipType: options.relationshipType,
+                    basePath: zipfile.splitPath(mainDocumentPath).dirname,
+                    fallbackPath: options.fallbackPath
+                });
+            }
+        
+            return {
+                mainDocument: mainDocumentPath,
+                comments: findPartRelatedToMainDocument({
+                    relationshipType: "http://schemas.openxmlformats.org/officeDocument/2006/relationships/comments",
+                    fallbackPath: "word/comments.xml"
+                }),
+                endnotes: "word/endnotes.xml",
+                footnotes: "word/footnotes.xml",
+                numbering: "word/numbering.xml",
+                styles: "word/styles.xml"
+            };
+        });
     });
 }
 
-function findDocumentFilename(docxFile, relationships) {
-    var officeDocumentType = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument";
-    var targets = relationships.findTargetsByType(officeDocumentType).concat(["word/document.xml"]);
+function findPartPath(options) {
+    var docxFile = options.docxFile;
+    var relationships = options.relationships;
+    var relationshipType = options.relationshipType;
+    var basePath = options.basePath;
+    var fallbackPath = options.fallbackPath;
+    
+    var targets = relationships.findTargetsByType(relationshipType);
     var normalisedTargets = targets.map(function(target) {
-        return stripPrefix(target, "/");
+        return stripPrefix(zipfile.joinPath(basePath, target), "/");
     });
     var validTargets = normalisedTargets.filter(function(target) {
         return docxFile.exists(target);
     });
     if (validTargets.length === 0) {
-        throw new Error("Could not find main document part. Are you sure this is a valid .docx file?");
+        return fallbackPath;
     } else {
         return validTargets[0];
     }
diff --git a/lib/zipfile.js b/lib/zipfile.js
index ae51310..8d46d92 100644
--- a/lib/zipfile.js
+++ b/lib/zipfile.js
@@ -51,7 +51,19 @@ function splitPath(path) {
 }
 
 function joinPath() {
-    return Array.prototype.filter.call(arguments, function(path) {
+    var nonEmptyPaths = Array.prototype.filter.call(arguments, function(path) {
         return path;
-    }).join("/");
+    });
+    
+    var relevantPaths = [];
+    
+    nonEmptyPaths.forEach(function(path) {
+        if (/^\//.test(path)) {
+            relevantPaths = [path];
+        } else {
+            relevantPaths.push(path);
+        }
+    });
+    
+    return relevantPaths.join("/");
 }