1 files changed, 41 insertions, 96 deletions

diff --git a/nihil.config/store.ccm b/nihil.config/store.ccm
index 7ed4ccb..e0eebc0 100644
--- a/nihil.config/store.ccm
+++ b/nihil.config/store.ccm
@@ -9,12 +9,12 @@ module;
  */
 
 #include <coroutine>
+#include <filesystem>
 #include <format>
 #include <map>
 
 export module nihil.config:store;
 
-import nihil;
 import :error;
 import :option;
 
@@ -22,15 +22,22 @@ namespace nihil::config {
 
 // Exception thrown on an attempt to fetch an undefined option.
 export struct unknown_option final : error {
-	std::string varname;
-
-	unknown_option(std::string_view varname_)
-		: error("unknown configuration variable '{}'", varname_)
-		, varname(varname_)
+	unknown_option(std::string_view option_name)
+		: error(std::format("unknown configuration variable '{}'",
+				    option_name))
+		, _option_name(option_name)
 	{}
+
+	auto option_name(this unknown_option const &self) -> std::string_view
+	{
+		return self._option_name;
+	}
+
+private:
+	std::string _option_name;
 };
 
-export struct store final {
+struct store final {
 	/*
 	 * Get the global config store.
 	 */
@@ -41,52 +48,6 @@ export struct store final {
 		return *instance;
 	}
 
-	/*
-	 * Initialise the global config store.
-	 */
-#if 0
-	void init(context const &ctx) {
-		std::string config_text;
-
-		// Load the configuration text.
-		auto config_path = ctx.dbdir / "config.ucl";
-		try {
-			read_file(config_path, std::back_inserter(config_text));
-		} catch (io_error const &exc) {
-			// Ignore ENOENT, it simply means we haven't created the
-			// config file yet, so default values will be used.
-			if (exc.error == std::errc::no_such_file_or_directory)
-				return;
-			throw;
-		}
-
-		// Parse the UCL.
-
-		std::string err;
-		auto uclconfig = ucl::Ucl::parse(config_text, err);
-
-		if (!uclconfig)
-			throw error("{0}: {1}", config_path, err);
-
-		auto const &cfg = get();
-		for (auto const &uclvalue : uclconfig) {
-			auto &value = cfg.fetch(uclvalue.key());
-
-			switch (uclvalue.type()) {
-			case UCL_INT:
-				value.integer(uclvalue.int_value());
-				break;
-			case UCL_STRING:
-				value.string(uclvalue.string_value());
-				break;
-			default:
-				throw error(
-					"INTERNAL ERROR: unknown value type {0}",
-					static_cast<int>(uclvalue.type()));
-			}
-		}
-	}
-#endif
 
 	/*
 	 * Register a new value with the config store.
@@ -96,12 +57,26 @@ export struct store final {
 		auto [it, okay] = self.options.insert(
 					std::pair{object->name(), object});
 
-		if (okay)
-			return;
+		if (!okay)
+			throw error(std::format(
+				"INTERNAL ERROR: attempt to register "
+				"duplicate config value '{0}'",
+				object->name()));
+	}
 
-		throw error("INTERNAL ERROR: attempt to register "
-			    "duplicate config value '{0}'",
-			    object->name());
+	/*
+	 * Remove a value from the config store.
+	 */
+	auto unregister_option(this store &self, option *object) -> void
+	{
+		auto it = self.options.find(object->name());
+		if (it == self.options.end())
+			throw error(std::format(
+				"INTERNAL ERROR: attempt to unregister "
+				"non-existent config value '{}'",
+				object->name()));
+
+		self.options.erase(it);
 	}
 
 	/*
@@ -125,44 +100,6 @@ export struct store final {
 			co_yield *it.second;
 	}
 
-	/*
-	 * Write all config values (except defaults) to disk.
-	 */
-#if 0
-	void store::write_all(this store const &self, context const &ctx) {
-		// The UCL C++ API doesn't seem to support creating new objects
-		// from scratch, so we use the C API here.  We should probably
-		// provider a better wrapper for this.
-
-		auto ucl = ::ucl_object_typed_new(UCL_OBJECT);
-		auto ucl_guard = guard([ucl] { ::ucl_object_unref(ucl); });
-
-		// Add all the options to the UCL object.
-		for (auto const &option : self.fetch_all()) {
-			if (option.is_default)
-				continue;
-
-			option.add_to_ucl(ucl);
-		}
-
-		// Dump the UCL object to a string.
-		auto *ucl_c_text = reinterpret_cast<char *>(
-					::ucl_object_emit(ucl, UCL_EMIT_CONFIG));
-		//NOLINTNEXTLINE(cppcoreguidelines-no-malloc)
-		auto ucl_text_guard = guard([ucl_c_text] { ::free(ucl_c_text); });
-		std::string ucl_text(ucl_c_text);
-
-		// Write the object to a file.
-		auto config_path = ctx.dbdir / "config.ucl";
-
-		try {
-			safe_write_file(config_path, ucl_text);
-		} catch (io_error const &exc) {
-			throw error("{}", exc.what());
-		}
-	}
-#endif
-
 	// Not movable or copyable.
 	store(store const &) = delete;
 	store(store &&) = delete;
@@ -180,4 +117,12 @@ private:
 	store() = default;
 };
 
+/*
+ * The public API.
+ */
+export auto get_option(std::string_view option_name) -> option &
+{
+	return store::get().fetch(option_name);
+}
+
 } // namespace nihil::config