From 66e12978ba6e289e64971ccbe933448cc7020123 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Tue, 7 Apr 2015 12:35:46 +0530
Subject: [PATCH] PDF Metadata: When choosing between reading metadata from the
 Info dict and the XMP block, consider both the MetadataData and the
 ModifyDate in the XMP block, since there exist PDF metadata writing tools
 that update one and not the other. See #1440304 ([Enhancement] configure
 metadata import when importing pdf file in calibre)

---
 src/calibre/ebooks/metadata/xmp.py | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/src/calibre/ebooks/metadata/xmp.py b/src/calibre/ebooks/metadata/xmp.py
index 2c86dd0209..43059856a5 100644
--- a/src/calibre/ebooks/metadata/xmp.py
+++ b/src/calibre/ebooks/metadata/xmp.py
@@ -199,6 +199,23 @@ def read_xmp_identifers(parent):
         else:
             yield scheme[0].text or '', value
 
+def safe_parse_date(raw):
+    if raw:
+        try:
+            return parse_date(raw)
+        except Exception:
+            pass
+
+def more_recent(one, two):
+    if one is None:
+        return two
+    if two is None:
+        return one
+    try:
+        return max(one, two)
+    except Exception:
+        return one
+
 def metadata_from_xmp_packet(raw_bytes):
     root = parse_xmp_packet(raw_bytes)
     mi = Metadata(_('Unknown'))
@@ -226,12 +243,11 @@ def metadata_from_xmp_packet(raw_bytes):
     bkp = first_simple('//xmp:CreatorTool', root)
     if bkp:
         mi.book_producer = bkp
-    md = first_simple('//xmp:MetadataDate', root)
-    if md:
-        try:
-            mi.metadata_date = parse_date(md)
-        except:
-            pass
+    md = safe_parse_date(first_simple('//xmp:MetadataDate', root))
+    mod = safe_parse_date(first_simple('//xmp:ModifyDate', root))
+    fd = more_recent(md, mod)
+    if fd is not None:
+        mi.metadata_date = fd
     rating = first_simple('//calibre:rating', root)
     if rating is not None:
         try:
@@ -311,7 +327,7 @@ def consolidate_metadata(info_mi, info):
     if 'ModDate' in info and hasattr(xmp_mi, 'metadata_date'):
         try:
             info_date = parse_date(info['ModDate'])
-        except:
+        except Exception:
             pass
         else:
             prefer_info = info_date > xmp_mi.metadata_date