From c1f8016f6609477649e381423a641e8bd38432c8 Mon Sep 17 00:00:00 2001
From: King_DuckZ <king_duckz@posteo.net>
Date: Wed, 2 Apr 2025 21:23:26 +0100
Subject: [PATCH] Add helper find function

Hash calculation is only correct if the relative path
found in the torrent file is accessible from pwd
---
 src/main.cpp | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index e633060..7595e48 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -108,8 +108,8 @@ struct PrintVisitor {
 };
 
 struct FindStringVisitor : boost::static_visitor<std::string_view> {
-	FindStringVisitor (std::string path) {
-		auto split = dincore::split(path, '/', true, true);
+	FindStringVisitor (std::string_view search_path) {
+		auto split = dincore::split(search_path, '/', true, true);
 		search.reserve(split.size());
 		for (const auto& itm : split) {
 			search.emplace_back(itm.data(), itm.size());
@@ -188,6 +188,16 @@ std::vector<std::array<std::uint32_t, 5>> collect_hashes (std::string_view hashe
 	}
 	return retval;
 }
+
+std::string_view find_item(std::string_view path, const std::vector<duck::TorrentValue>& values) {
+	FindStringVisitor visitor(path);
+	for (const auto& value : values) {
+		std::string_view found = boost::apply_visitor(visitor, value);
+		if (not found.empty())
+			return found;
+	}
+	return {};
+}
 } //unnamed namespace
 
 int main(int argc, const char* argv[]) {
@@ -208,9 +218,8 @@ int main(int argc, const char* argv[]) {
 		boost::apply_visitor(visitor, value);
 	}
 
-	if (values.size() == 1) {
-		FindStringVisitor visitor("/info/pieces");
-		auto source_hashes = boost::apply_visitor(visitor, values.front());
+	{
+		auto source_hashes = find_item("/info/pieces", values);
 		std::cout << "Got source_hashes with size " << source_hashes.size() << '\n';
 		auto hashes = collect_hashes(source_hashes);
 		std::cout << "Got " << hashes.size() << " hashes\n";
@@ -222,12 +231,14 @@ int main(int argc, const char* argv[]) {
 		}
 	}
 
+	std::string_view file_name = find_item("/info/name", values);
+	std::cout << "Found file name \"" << file_name << "\"\n";
+
 	{
 		SHA1::MessageDigest hash160;
 		SHA1::FileSource file_source;
-		const char* const hash_path = argv[1];
-		file_source.open(hash_path);
+		file_source.open(std::string{file_name});
 		hash160 = SHA1::computeFromSource(file_source);
-		std::cout << hash160.toHexString() << "  " << hash_path << '\n';
+		std::cout << hash160.toHexString() << "  " << file_name << '\n';
 	}
 }