From 60adc5a3312a9412b8988a0e2e82724779b5b84e Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Thu, 19 Nov 2020 15:04:28 +0100
Subject: [PATCH] Recover subtitle language metadata from the places is was
 written in older films.

---
 src/lib/film.cc                | 33 +++++++++++++++
 test/data                      |  2 +-
 test/subtitle_metadata_test.cc | 76 ++++++++++++++++++++++++++++++++++
 test/wscript                   |  1 +
 4 files changed, 111 insertions(+), 1 deletion(-)
 create mode 100644 test/subtitle_metadata_test.cc

diff --git a/src/lib/film.cc b/src/lib/film.cc
index 9943711f5..5d298baae 100644
--- a/src/lib/film.cc
+++ b/src/lib/film.cc
@@ -686,6 +686,39 @@ Film::read_metadata (optional<boost::filesystem::path> path)
 		set_backtrace_file (file ("backtrace.txt"));
 	}
 
+	/* Around 2.15.108 we removed subtitle language state from the text content and the ISDCF
+	 * metadata and put it into the Film instead.  If we've loaded an old Film let's try and fish
+	 * out the settings from where they were so that they don't get lost.
+	 */
+
+	optional<dcp::LanguageTag> found_language;
+
+	BOOST_FOREACH (cxml::ConstNodePtr i, f.node_child("Playlist")->node_children("Content")) {
+		cxml::ConstNodePtr text = i->optional_node_child("Text");
+		if (text && text->optional_string_child("Language") && !found_language) {
+			try {
+				found_language = dcp::LanguageTag(text->string_child("Language"));
+			} catch (...) {}
+		}
+	}
+
+	optional<string> isdcf_language = f.node_child("ISDCFMetadata")->optional_string_child("SubtitleLanguage");
+	if (isdcf_language && !found_language) {
+		try {
+			found_language = dcp::LanguageTag(*isdcf_language);
+		} catch (...) {
+			try {
+				found_language = dcp::LanguageTag(boost::algorithm::to_lower_copy(*isdcf_language));
+			} catch (...) {
+
+			}
+		}
+	}
+
+	if (found_language) {
+		_subtitle_languages.push_back (*found_language);
+	}
+
 	_dirty = false;
 	return notes;
 }
diff --git a/test/data b/test/data
index 30022e624..eebc165cf 160000
--- a/test/data
+++ b/test/data
@@ -1 +1 @@
-Subproject commit 30022e624852127f464933f5008f8ac6226d831c
+Subproject commit eebc165cf7df4af980e918bc3176d93521f5beea
diff --git a/test/subtitle_metadata_test.cc b/test/subtitle_metadata_test.cc
new file mode 100644
index 000000000..a60d0675c
--- /dev/null
+++ b/test/subtitle_metadata_test.cc
@@ -0,0 +1,76 @@
+/*
+    Copyright (C) 2020 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+/** @file  test/subtitle_metadata_test.cc
+ *  @brief Test that subtitle language metadata is recovered from metadata files
+ *  written by versions before the subtitle language was only stored in Film.
+ */
+
+
+#include "lib/film.h"
+#include "test.h"
+#include <boost/filesystem.hpp>
+#include <boost/shared_ptr.hpp>
+#include <boost/test/unit_test.hpp>
+
+
+using std::vector;
+using boost::shared_ptr;
+
+
+BOOST_AUTO_TEST_CASE (subtitle_metadata_test1)
+{
+	using namespace boost::filesystem;
+
+	path p = test_film_dir ("subtitle_metadata_test1");
+	if (exists (p)) {
+		remove_all (p);
+	}
+	create_directory (p);
+
+	copy_file ("test/data/subtitle_metadata1.xml", p / "metadata.xml");
+	shared_ptr<Film> film(new Film(p));
+	film->read_metadata();
+
+	vector<dcp::LanguageTag> langs = film->subtitle_languages ();
+	BOOST_REQUIRE (!langs.empty());
+	BOOST_CHECK_EQUAL (langs.front().to_string(), "de-DE");
+}
+
+
+BOOST_AUTO_TEST_CASE (subtitle_metadata_test2)
+{
+	using namespace boost::filesystem;
+
+	path p = test_film_dir ("subtitle_metadata_test2");
+	if (exists (p)) {
+		remove_all (p);
+	}
+	create_directory (p);
+
+	copy_file ("test/data/subtitle_metadata2.xml", p / "metadata.xml");
+	shared_ptr<Film> film(new Film(p));
+	film->read_metadata();
+
+	vector<dcp::LanguageTag> langs = film->subtitle_languages ();
+	BOOST_REQUIRE (!langs.empty());
+	BOOST_CHECK_EQUAL (langs.front().to_string(), "fr");
+}
+
diff --git a/test/wscript b/test/wscript
index ec01bf4f8..9a3347be3 100644
--- a/test/wscript
+++ b/test/wscript
@@ -118,6 +118,7 @@ def build(bld):
                  ssa_subtitle_test.cc
                  stream_test.cc
                  subtitle_charset_test.cc
+                 subtitle_metadata_test.cc
                  subtitle_reel_test.cc
                  subtitle_reel_number_test.cc
                  subtitle_trim_test.cc
-- 
2.30.2