From 394516c351602f58150bdbbb4e61c45163927147 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Wed, 6 Mar 2024 01:17:59 +0100
Subject: [PATCH] Use stored has_non_zero_entry_point() instead of parsing the
 DCP again (#2524).

---
 src/lib/dcp_content.cc        | 35 ++++--------------
 test/text_entry_point_test.cc | 70 +++++++++++++++++++++++++++++++++++
 test/wscript                  |  1 +
 3 files changed, 78 insertions(+), 28 deletions(-)
 create mode 100644 test/text_entry_point_test.cc

diff --git a/src/lib/dcp_content.cc b/src/lib/dcp_content.cc
index 35ef15442..e583578ec 100644
--- a/src/lib/dcp_content.cc
+++ b/src/lib/dcp_content.cc
@@ -750,37 +750,16 @@ DCPContent::can_reference_audio (shared_ptr<const Film> film, string& why_not) c
 bool
 DCPContent::can_reference_text (shared_ptr<const Film> film, TextType type, string& why_not) const
 {
-	shared_ptr<DCPDecoder> decoder;
-	try {
-		decoder = make_shared<DCPDecoder>(film, shared_from_this(), false, film->tolerant(), shared_ptr<DCPDecoder>());
-	} catch (dcp::ReadError &) {
-		/* We couldn't read the DCP, so it's probably missing */
-		return false;
-	} catch (DCPError &) {
-		/* We couldn't read the DCP, so it's probably missing */
-		return false;
-	} catch (dcp::KDMDecryptionError &) {
-		/* We have an incorrect KDM */
+	if (_has_non_zero_entry_point[TextType::OPEN_SUBTITLE]) {
+		/// TRANSLATORS: this string will follow "Cannot reference this DCP: "
+		why_not = _("one of its subtitle reels has a non-zero entry point so it must be re-written.");
 		return false;
 	}
 
-        for (auto i: decoder->reels()) {
-                if (type == TextType::OPEN_SUBTITLE) {
-			if (i->main_subtitle() && i->main_subtitle()->entry_point().get_value_or(0) != 0) {
-				/// TRANSLATORS: this string will follow "Cannot reference this DCP: "
-				why_not = _("one of its subtitle reels has a non-zero entry point so it must be re-written.");
-				return false;
-			}
-                }
-		if (type == TextType::CLOSED_CAPTION) {
-			for (auto j: i->closed_captions()) {
-				if (j->entry_point().get_value_or(0) != 0) {
-					/// TRANSLATORS: this string will follow "Cannot reference this DCP: "
-					why_not = _("one of its closed caption has a non-zero entry point so it must be re-written.");
-					return false;
-				}
-			}
-		}
+	if (_has_non_zero_entry_point[TextType::CLOSED_CAPTION]) {
+		/// TRANSLATORS: this string will follow "Cannot reference this DCP: "
+		why_not = _("one of its closed caption has a non-zero entry point so it must be re-written.");
+		return false;
         }
 
 	if (trim_start() != dcpomatic::ContentTime()) {
diff --git a/test/text_entry_point_test.cc b/test/text_entry_point_test.cc
new file mode 100644
index 000000000..ce4f6148e
--- /dev/null
+++ b/test/text_entry_point_test.cc
@@ -0,0 +1,70 @@
+/*
+    Copyright (C) 2024 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/>.
+
+*/
+
+
+#include "test.h"
+#include "lib/dcp_content.h"
+#include "lib/film.h"
+#include <dcp/cpl.h>
+#include <dcp/dcp.h>
+#include <dcp/reel.h>
+#include <dcp/reel_smpte_subtitle_asset.h>
+#include <dcp/smpte_subtitle_asset.h>
+#include <boost/test/unit_test.hpp>
+
+
+using std::make_shared;
+using std::string;
+
+
+BOOST_AUTO_TEST_CASE(test_text_entry_point)
+{
+	auto const path = boost::filesystem::path("build/test/test_text_entry_point");
+	boost::filesystem::remove_all(path);
+	boost::filesystem::create_directories(path);
+
+	/* Make a "bad" DCP with a non-zero text entry point */
+	dcp::DCP bad_dcp(path / "dcp");
+	auto sub = make_shared<dcp::SMPTESubtitleAsset>();
+	sub->write(path / "dcp" / "subs.mxf");
+	auto reel_sub = make_shared<dcp::ReelSMPTESubtitleAsset>(sub, dcp::Fraction{24, 1}, 42, 6);
+	auto reel = make_shared<dcp::Reel>();
+	reel->add(reel_sub);
+
+	auto cpl = make_shared<dcp::CPL>("foo", dcp::ContentKind::FEATURE, dcp::Standard::SMPTE);
+	bad_dcp.add(cpl);
+	cpl->add(reel);
+
+	bad_dcp.write_xml();
+
+	/* Make a film and add the bad DCP, so that the examiner spots the problem */
+	auto dcp_content = make_shared<DCPContent>(path / "dcp");
+	auto film = new_test_film2("test_text_entry_point/film", { dcp_content });
+	film->write_metadata();
+
+	/* Reload the film to check that the examiner's output is saved and recovered */
+	auto film2 = make_shared<Film>(path / "film");
+	film2->read_metadata();
+
+	string why_not;
+	BOOST_CHECK(!dcp_content->can_reference_text(film2, TextType::OPEN_SUBTITLE, why_not));
+	BOOST_CHECK_EQUAL(why_not, "one of its subtitle reels has a non-zero entry point so it must be re-written.");
+}
+
diff --git a/test/wscript b/test/wscript
index 400d8ea74..eb8901338 100644
--- a/test/wscript
+++ b/test/wscript
@@ -162,6 +162,7 @@ def build(bld):
                  template_test.cc
                  test.cc
                  text_decoder_test.cc
+                 text_entry_point_test.cc
                  threed_test.cc
                  time_calculation_test.cc
                  torture_test.cc
-- 
2.30.2