From 1b774d7718b398ee0b4241b0c61305c87bc00efe Mon Sep 17 00:00:00 2001
From: Adrian Johnson <ajohnson@redneon.com>
Date: Thu, 7 Sep 2017 22:54:56 +0930
Subject: [PATCH] Include timezone in timeToDateString()

---
 poppler/DateInfo.cc | 59 ++++++++++++++++++++++-------------------------------
 poppler/DateInfo.h  |  1 +
 2 files changed, 25 insertions(+), 35 deletions(-)

diff --git a/poppler/DateInfo.cc b/poppler/DateInfo.cc
index fef3f00a..2580dab9 100644
--- a/poppler/DateInfo.cc
+++ b/poppler/DateInfo.cc
@@ -77,41 +77,30 @@ GBool parseDateString(const char *dateString, int *year, int *month, int *day, i
 }
 
 // Convert time to PDF date string
-GooString *timeToDateString(time_t *timet) {
-  GooString *dateString;
-  char s[5];
-  struct tm *gt;
-  size_t len;
-  time_t timep = timet ? *timet : time(NULL);
-  struct tm t;
-
-  gt = gmtime_r (&timep, &t);
-
-  dateString = new GooString ("D:");
-
-  /* Year YYYY */
-  len = strftime (s, sizeof(s), "%Y", gt);
-  dateString->append (s, len);
-
-  /* Month MM */
-  len = strftime (s, sizeof(s), "%m", gt);
-  dateString->append (s, len);
-
-  /* Day DD */
-  len = strftime (s, sizeof(s), "%d", gt);
-  dateString->append (s, len);
-
-  /* Hour HH */
-  len = strftime (s, sizeof(s), "%H", gt);
-  dateString->append (s, len);
-
-  /* Minute mm */
-  len = strftime (s, sizeof(s), "%M", gt);
-  dateString->append (s, len);
-
-  /* Second SS */
-  len = strftime (s, sizeof(s), "%S", gt);
-  dateString->append (s, len);
+GooString *timeToDateString(time_t *timeA)
+{
+  time_t timet = timeA ? *timeA : time(NULL);
+
+  struct tm localtime_tm;
+  localtime_r (&timet, &localtime_tm);
+
+  char buf[50];
+  strftime (buf, sizeof(buf), "D:%Y%m%d%H%M%S", &localtime_tm);
+  GooString *dateString = new GooString(buf);
+
+  // strftime "%z" does not work on windows (it prints zone name, not offset)
+  // calculate time zone offset by comparing local and gmtime time_t value for same
+  // time.
+  time_t timeg = timegm(&localtime_tm);
+  time_t offset = difftime(timeg, timet); // find time zone offset in seconds
+  if (offset > 0) {
+    dateString->appendf ("+{0:02d}'{1:02d}", offset/3600, (offset%3600)/60);
+  } else if (offset < 0) {
+    offset = -offset;
+    dateString->appendf ("-{0:02d}'{1:02d}", offset/3600, (offset%3600)/60);
+  } else {
+    dateString->append("Z");
+  }
 
   return dateString;
 }
diff --git a/poppler/DateInfo.h b/poppler/DateInfo.h
index 468dd93b..1956e904 100644
--- a/poppler/DateInfo.h
+++ b/poppler/DateInfo.h
@@ -32,6 +32,7 @@ GBool parseDateString(const char *string, int *year, int *month, int *day, int *
 
 /* Converts the time_t into a PDF Date format string.
  * If timet is NULL, current time is used.
+ * Returns new GooString. Free with delete.
  */
 GooString *timeToDateString(time_t *timet);
 
-- 
2.11.0