import std.file, std.regex, std.stdio;

struct Config
{
	private string[string] values;

	this(string[] filenames...)
	{
		bool found = false;
		foreach (filename; filenames) {
			if (exists(filename)) {
				found = true;
				load(filename);
			}
		}
		if (!found) throw new Exception("No config file found");
	}

	string get(string key)
	{
		auto p = key in values;
		if (p) {
			return *p;
		} else {
			throw new Exception("Missing config value: " ~ key);
		}
	}

	private void load(string filename)
	{
		auto file = File(filename, "r");
		auto r = regex("(?:^\\s*)(\\w+)(?:\\s*=\\s*\")(.*)(?:\"\\s*$)");
		foreach (line; file.byLine()) {
			auto c = line.matchFirst(r);
			if (!c.empty) {
				c.popFront(); // skip the whole match
				string key = c.front.dup;
				c.popFront();
				values[key] = c.front.dup;
			} else {
				writeln("Malformed config line: ", line);
			}
		}
	}
}

unittest
{
	auto cfg = Config("empty", "onedrive.conf");
	assert(cfg.get("sync_dir") == "~/OneDrive");
}

unittest
{
	try {
		auto cfg = Config("empty");
		assert(0);
	} catch (Exception e) {
	}
}