Start on import wizard and move JSON wrappers into NostalgiaStudio library

src/nostalgia/studio/lib/json_read.hpp

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2016-2017 gtalent2@gmail.com
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <QJsonArray>
+#include <QJsonObject>
+#include <QJsonDocument>
+#include "json_operator.hpp"
+
+namespace nostalgia {
+namespace studio {
+
+enum {
+	JSON_ERR_FIELD_MISSING,
+	JSON_ERR_UNEXPECTED_TYPE,
+};
+
+class JsonReader {
+
+	private:
+		QJsonObject &m_src;
+
+	public:
+		JsonReader(QJsonObject &obj);
+
+		ox::Error op(QString fieldName, int *dest);
+
+		ox::Error op(QString fieldName, bool *dest);
+
+		ox::Error op(QString fieldName, double *dest);
+
+		ox::Error op(QString fieldName, QString *dest);
+
+		template<typename T>
+		ox::Error op(QString fieldName, T *dest);
+
+		template<typename T>
+		ox::Error op(QString fieldName, QVector<T> *dest);
+
+	private:
+		ox::Error op(QJsonValueRef src, int *dest);
+
+		ox::Error op(QJsonValueRef src, bool *dest);
+
+		ox::Error op(QJsonValueRef src, double *dest);
+
+		ox::Error op(QJsonValueRef src, QString *dest);
+
+};
+
+template<typename T>
+ox::Error JsonReader::op(QString fieldName, T *dest) {
+	auto obj = m_src[fieldName].toObject();
+	auto reader = JsonReader(obj);
+	return ioOp(&reader, dest);
+};
+
+template<typename T>
+ox::Error JsonReader::op(QString fieldName, QVector<T> *dest) {
+	ox::Error err = 0;
+	auto a = m_src[fieldName].toArray();
+	dest->resize(a.size());
+	for (int i = 0; i < dest->size(); i++) {
+		err |= op(a[i], &dest->at(i));
+	}
+	return err;
+};
+
+template<typename T>
+int read(QString json, T *dest) {
+	auto obj = QJsonDocument::fromJson(json.toUtf8()).object();
+	JsonReader rdr(obj);
+	return ioOp(&rdr, dest);
+}
+
+}
+}