From a621072e7de9b55f8ff0fdfec84d87249139121c Mon Sep 17 00:00:00 2001
From: Ryan Lucia <ryan@luciaonline.net>
Date: Thu, 10 May 2018 03:28:51 -0400
Subject: [PATCH] Add support for WWXD keyframes in qpfile format

---
 libaegisub/common/keyframe.cpp           | 42 +++++++++++++++++++-----
 libaegisub/include/libaegisub/keyframe.h |  3 +-
 src/project.cpp                          |  6 +++-
 3 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/libaegisub/common/keyframe.cpp b/libaegisub/common/keyframe.cpp
index 50e537338..b2855bd11 100644
--- a/libaegisub/common/keyframe.cpp
+++ b/libaegisub/common/keyframe.cpp
@@ -19,6 +19,8 @@
 
 #include "libaegisub/keyframe.h"
 
+#include <sstream>
+
 #include "libaegisub/io.h"
 #include "libaegisub/line_iterator.h"
 
@@ -35,10 +37,9 @@ std::vector<int> agi_keyframes(std::istream &file) {
 	return std::vector<int>(agi::line_iterator<int>(file), agi::line_iterator<int>());
 }
 
-std::vector<int> other_keyframes(std::istream &file, char (*func)(std::string const&)) {
+std::vector<int> enumerated_keyframes(std::istream &file, char (*func)(std::string const&)) {
 	int count = 0;
 	std::vector<int> ret;
-	agi::line_iterator<std::string> end;
 	for (auto line : agi::line_iterator<std::string>(file)) {
 		char c = tolower(func(line));
 		if (c == 'i')
@@ -49,6 +50,16 @@ std::vector<int> other_keyframes(std::istream &file, char (*func)(std::string co
 	return ret;
 }
 
+std::vector<int> indexed_keyframes(std::istream &file, int (*func)(std::string const&)) {
+	std::vector<int> ret;
+	for (auto line : agi::line_iterator<std::string>(file)) {
+		int frame_no = func(line);
+		if (frame_no >= 0)
+			ret.push_back(frame_no);
+	}
+	return ret;
+}
+
 char xvid(std::string const& line) {
 	return line.empty() ? 0 : line[0];
 }
@@ -68,6 +79,20 @@ char x264(std::string const& line) {
 	if (pos == line.npos || pos + 5 >= line.size()) return 0;
 	return line[pos + 5];
 }
+
+int wwxd(std::string const& line) {
+	if (line.empty() || line[0] == '#')
+		return -1;
+	std::istringstream ss(line);
+	int frame_no;
+	char frame_type;
+	ss >> frame_no >> frame_type;
+	if (ss.fail())
+		throw agi::keyframe::KeyframeFormatParseError("WWXD keyframe file not in qpfile format");
+	if (frame_type == 'I')
+		return frame_no;
+	return -1;
+}
 }
 
 namespace agi { namespace keyframe {
@@ -87,13 +112,14 @@ std::vector<int> Load(agi::fs::path const& filename) {
 	getline(is, header);
 
 	if (header == "# keyframe format v1") return agi_keyframes(is);
-	if (boost::starts_with(header, "# XviD 2pass stat file")) return other_keyframes(is, xvid);
-	if (boost::starts_with(header, "# ffmpeg 2-pass log file, using xvid codec")) return other_keyframes(is, xvid);
-	if (boost::starts_with(header, "# avconv 2-pass log file, using xvid codec")) return other_keyframes(is, xvid);
-	if (boost::starts_with(header, "##map version")) return other_keyframes(is, divx);
-	if (boost::starts_with(header, "#options:")) return other_keyframes(is, x264);
+	if (boost::starts_with(header, "# XviD 2pass stat file")) return enumerated_keyframes(is, xvid);
+	if (boost::starts_with(header, "# ffmpeg 2-pass log file, using xvid codec")) return enumerated_keyframes(is, xvid);
+	if (boost::starts_with(header, "# avconv 2-pass log file, using xvid codec")) return enumerated_keyframes(is, xvid);
+	if (boost::starts_with(header, "##map version")) return enumerated_keyframes(is, divx);
+	if (boost::starts_with(header, "#options:")) return enumerated_keyframes(is, x264);
+	if (boost::starts_with(header, "# WWXD log file, using qpfile format")) return indexed_keyframes(is, wwxd);
 
-	throw Error("Unknown keyframe format");
+	throw UnknownKeyframeFormatError("File header does not match any known formats");
 }
 
 } }
diff --git a/libaegisub/include/libaegisub/keyframe.h b/libaegisub/include/libaegisub/keyframe.h
index 43fb9333f..6fc82ff49 100644
--- a/libaegisub/include/libaegisub/keyframe.h
+++ b/libaegisub/include/libaegisub/keyframe.h
@@ -29,6 +29,7 @@ namespace agi {
 		/// @param keyframes List of keyframes to save
 		void Save(agi::fs::path const& filename, std::vector<int> const& keyframes);
 
-		DEFINE_EXCEPTION(Error, Exception);
+		DEFINE_EXCEPTION(KeyframeFormatParseError, agi::InvalidInputException);
+		DEFINE_EXCEPTION(UnknownKeyframeFormatError, agi::InvalidInputException);
 	}
 }
diff --git a/src/project.cpp b/src/project.cpp
index 312f86fe8..633a526b7 100644
--- a/src/project.cpp
+++ b/src/project.cpp
@@ -391,10 +391,14 @@ void Project::LoadKeyframes(agi::fs::path path) {
 		ShowError(e.GetMessage());
 		config::mru->Remove("Keyframes", path);
 	}
-	catch (agi::keyframe::Error const& e) {
+	catch (agi::keyframe::KeyframeFormatParseError const& e) {
 		ShowError("Failed to parse keyframes file: " + e.GetMessage());
 		config::mru->Remove("Keyframes", path);
 	}
+	catch (agi::keyframe::UnknownKeyframeFormatError const& e) {
+		ShowError("Keyframes file in unknown format: " + e.GetMessage());
+		config::mru->Remove("Keyframes", path);
+	}
 }
 
 void Project::CloseKeyframes() {