TSCDecrypt - Decrypts Cave Story *.tsc files into plain text.

tscdecrypt.cpp

#include <iostream>
#include <fstream>
#include <sstream>

class TSCDecrypt {
public:
	std::string decrypt_file(const std::string& file_name) const {
		// Read the file into a string.
		std::ifstream file(file_name);
		std::stringstream stream;
		stream << file.rdbuf();
		std::string contents = stream.str();

		// Decrypt contents.
		return decrypt(contents);
	}

	std::string decrypt(const std::string& content) const {
		// Get key.
		const char& key = content[content.size() / 2];
		std::string decrypted;

		// Decrypt characters.
		for (const char& char_ : content)
			decrypted += char_ - key;

		return decrypted;
	}
};

int main(int argc, char* argv[]) {
	if (argc == 1) {
		std::cerr << "usage: tscdecrypt [file]\n";
		return -1;
	} else {
		// Decrypt the file.
		TSCDecrypt decrypter;
		std::cout << decrypter.decrypt_file(std::string(argv[1]));
		std::cout << std::flush;
		return 0;
	}
}