1 files changed, 102 insertions, 0 deletions
diff --git a/nihil.ucl/parser.cc b/nihil.ucl/parser.cc
new file mode 100644
index 0000000..0a08670
--- /dev/null
+++ b/nihil.ucl/parser.cc
@@ -0,0 +1,102 @@
+/*
+ * This source code is released into the public domain.
+ */
+
+module;
+
+#include <expected>
+#include <functional>
+#include <string>
+
+#include <ucl.h>
+
+module nihil.ucl;
+
+import nihil.error;
+
+namespace nihil::ucl {
+
+auto make_parser(int flags) -> std::expected<parser, error>
+{
+	auto *p = ::ucl_parser_new(flags);
+	if (p != nullptr)
+		return p;
+
+	// TODO: Is there a way to get the actual error here?
+	return std::unexpected(error("failed to create parser"));
+}
+
+auto macro_handler::handle(unsigned char const *data,
+			   std::size_t len, void *ud)
+	-> bool
+{
+	auto handler = static_cast<macro_handler *>(ud);
+	auto string = std::string_view(
+			reinterpret_cast<char const *>(data),
+			len);
+	return handler->callback(string);
+}
+
+parser::parser(::ucl_parser *uclp)
+	: m_parser(uclp)
+{
+}
+
+parser::~parser()
+{
+	if (m_parser)
+		::ucl_parser_free(m_parser);
+}
+
+parser::parser(parser &&other) noexcept
+	: m_parser(std::exchange(other.m_parser, nullptr))
+	, m_macros(std::move(other.m_macros))
+{
+}
+
+auto parser::operator=(this parser &self, parser &&other) noexcept
+	-> parser &
+{
+	if (&self != &other) {
+		if (self.m_parser)
+			::ucl_parser_free(self.m_parser);
+
+		self.m_parser = std::exchange(other.m_parser, nullptr);
+		self.m_macros = std::move(other.m_macros);
+	}
+
+	return self;
+}
+
+auto parser::register_value(
+	this parser &self,
+	std::string_view variable,
+	std::string_view value)
+	-> void
+{
+	::ucl_parser_register_variable(
+		self.get_parser(),
+		std::string(variable).c_str(),
+		std::string(value).c_str());
+}
+
+auto parser::top(this parser &self) -> map<object>
+{
+	auto obj = ::ucl_parser_get_object(self.get_parser());
+	if (obj != nullptr)
+		// ucl_parser_get_object() refs the object for us.
+		return {noref, obj};
+
+	throw std::logic_error(
+		"attempt to call top() on an invalid ucl::parser");
+}
+
+auto parser::get_parser(this parser &self) -> ::ucl_parser *
+{
+	if (self.m_parser == nullptr)
+		throw std::logic_error("attempt to fetch a null ucl::parser");
+	
+	return self.m_parser;
+}
+
+} // namespace nihil::ucl