/*
 * 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);
}

}
}