Pass through CompositionMetadataAsset correctly.

We weren't saving Id, and were not quite handling FullContentText
correctly.

3 files changed, 24 insertions, 2 deletions

diff --git a/src/cpl.cc b/src/cpl.cc
index 0eb25052..20d22b65 100644
--- a/src/cpl.cc
+++ b/src/cpl.cc
@@ -237,6 +237,8 @@ CPL::write_xml (boost::filesystem::path file, shared_ptr<const CertificateChain>
 void
 CPL::read_composition_metadata_asset (cxml::ConstNodePtr node)
 {
+	_cpl_metadata_id = remove_urn_uuid(node->string_child("Id"));
+
 	auto fctt = node->node_child("FullContentTitleText");
 	_full_content_title_text = fctt->content();
 	_full_content_title_text_language = fctt->optional_string_attribute("language");
@@ -337,14 +339,14 @@ CPL::maybe_write_composition_metadata_asset (xmlpp::Element* node) const
 	auto meta = node->add_child("meta:CompositionMetadataAsset");
 	meta->set_namespace_declaration (cpl_metadata_ns, "meta");
 
-	meta->add_child("Id")->add_child_text("urn:uuid:" + make_uuid());
+	meta->add_child("Id")->add_child_text("urn:uuid:" + _cpl_metadata_id);
 
 	auto mp = _reels.front()->main_picture();
 	meta->add_child("EditRate")->add_child_text(mp->edit_rate().as_string());
 	meta->add_child("IntrinsicDuration")->add_child_text(raw_convert<string>(mp->intrinsic_duration()));
 
 	auto fctt = meta->add_child("FullContentTitleText", "meta");
-	if (_full_content_title_text) {
+	if (_full_content_title_text && !_full_content_title_text->empty()) {
 		fctt->add_child_text (*_full_content_title_text);
 	}
 	if (_full_content_title_text_language) {
diff --git a/src/cpl.h b/src/cpl.h
index 797c49d2..9c85dccd 100644
--- a/src/cpl.h
+++ b/src/cpl.h
@@ -323,6 +323,10 @@ private:
 	ContentKind _content_kind;                  ///< &lt;ContentKind&gt;
 	std::vector<ContentVersion> _content_versions;
 	std::vector<Rating> _ratings;
+	/** ID for CompositionMetadataAsset tag; either a random one, ready for writing a new tag,
+	 *  or the one read in from the existing CPL.
+	 */
+	std::string _cpl_metadata_id = make_uuid();
 	/** Human-readable name of the composition, without any metadata (i.e. no -FTR-EN-XX- etc.) */
 	boost::optional<std::string> _full_content_title_text;
 	boost::optional<std::string> _full_content_title_text_language;
diff --git a/test/combine_test.cc b/test/combine_test.cc
index 0dcfd2d3..e1512e41 100644
--- a/test/combine_test.cc
+++ b/test/combine_test.cc
@@ -397,5 +397,21 @@ BOOST_AUTO_TEST_CASE (combine_two_dcps_with_duplicated_asset)
 }
 
 
+BOOST_AUTO_TEST_CASE (check_cpls_unchanged_after_combine)
+{
+	boost::filesystem::path in = "build/test/combine_one_dcp_with_composition_metadata_in";
+	boost::filesystem::path out = "build/test/combine_one_dcp_with_composition_metadata_out";
+	auto dcp = make_simple (in);
+	dcp->write_xml ();
+
+	dcp::combine ({in}, out);
+
+	BOOST_REQUIRE_EQUAL (dcp->cpls().size(), 1U);
+	auto cpl = dcp->cpls()[0]->file();
+	BOOST_REQUIRE (cpl);
+	check_file (*cpl, out / cpl->filename());
+}
+
+
 /* XXX: same CPL names */
 /* XXX: Interop PNG subs */