MyChat_Client/model/datacenter.cpp

#include "datacenter.h"

namespace model
{
	DataCenter* DataCenter::instance = nullptr;

	DataCenter* DataCenter::getInstance()
	{
		if (instance == nullptr) {
			instance = new DataCenter();
		}
		return instance;
	}

	DataCenter::~DataCenter()
	{
		//释放所有的成员
		//此处就不必判断nullptr，直接delete即可
		//c++标准中明确规定了，对nullptr进行delete是合法行为，不会有任何副作用
		delete myself;
		delete friendList;
		delete chatSessionList;
		delete memberList;
		delete applyList;
		delete recentMessages;
		delete unreadMessageCount;
		delete searchUserResult;
		delete searchMessageResult;
	}

	DataCenter::DataCenter() : netClient(this)
	{
		//此处只是把这几个hash类型的属性进行new出实例，其他的QList都暂时不实例化
		//主要是为了使用nullptr表示非法状态
		//对于hash来说，不关心整个的QHash是否是nullptr，而是关心某个key对应的value是否存在
		//通过key是否存在，也能表示该值是否有效
		recentMessages = new QHash<QString, QList<Message>>();
		memberList = new QHash<QString, QList<UserInfo>>();
		unreadMessageCount = new QHash<QString, int>();

		//加载数据
		loadDataFile();
	}

	void DataCenter::initDataFile()
	{
		//构造出文件的路径，使用appData存储文件
		QString basePath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
		QString filePath = basePath + "/ChatClient.json";

		QDir dir;
		if (!dir.exists(basePath)) {
			//没有则进行目录的创建
			dir.mkpath(basePath);
		}

		//构造好文件的路径之后，把文件创建出来
		//写的方式打开，并且写入初始内容
		QFile file(filePath);
		if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
			LOG() << "initDataFile open file failed!!!" << file.errorString();
			file.close();
			return;
		}
		//打开成功，写入初始内容
		QString data = "{\n\n}";
		file.write(data.toUtf8());
		file.close();
	}

	void DataCenter::saveDataFile()
	{
		QString basePath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
		QString filePath = basePath + "/ChatClient.json";

		QFile file(filePath);
		if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
			LOG() << "saveDataFile open file failed!!!" << file.errorString();
			file.close();
			return;
		}

		//按照json格式进行数据的写入
		//这个对象可以当作map一样来使用
		QJsonObject jsonObj;
		jsonObj["loginSessionId"] = loginSessionId;
		
		QJsonObject jsonUnread;
		for (auto it = unreadMessageCount->begin(); it != unreadMessageCount->end(); ++it) {
			//注意此处的qt迭代器使用和stl有区别（不是使用first和second）
			jsonUnread[it.key()] = it.value();
		}
		jsonObj["unread"] = jsonUnread;

		//把json写入文件
		QJsonDocument jsonDoc(jsonObj);
		QString s = jsonDoc.toJson();
		file.write(s.toUtf8());

		//关闭文件
		file.close();
	}

	//加载文件，在DataCenter实例化就应该执行的
	void DataCenter::loadDataFile()
	{
		//确保加载之前就针对文件进行初始化操作
		QString basePath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
		QString filePath = basePath + "/ChatClient.json";

		//判定文件是否存在，不存在则初始化，并创建出空空白的json文件
		QFileInfo fileInfo(filePath);
		if (!fileInfo.exists()) {
			initDataFile();
		}

		//按读方式打开文件
		QFile file(filePath);
		if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
			LOG() << "loadDataFile open file failed!!!" << file.errorString();
			return;
		}

		//读取文件内容，解析为 JSON对象
		QJsonDocument jsonDoc = QJsonDocument::fromJson(file.readAll());
		if (jsonDoc.isNull()) {
			LOG() << "loadDataFile parsing the json file failed!!!";
			file.close();
			return;
		}

		QJsonObject jsonObj = jsonDoc.object();
		this->loginSessionId = jsonObj["loginSessionId"].toString();


		this->unreadMessageCount->clear();
		QJsonObject jsonUnread = jsonObj["unread"].toObject();
		for (auto it = jsonUnread.begin(); it != jsonUnread.end(); ++it) {
			this->unreadMessageCount->insert(it.key(), it.value().toInt());
		}

		file.close();
	}

	void DataCenter::getMyselfAsync()
	{
		//DataCenter 只是负责“处理数据”，
		//而真正负责网络进行通信，需要通过NetClient
		netClient.getMyself(loginSessionId);
	}

	UserInfo* DataCenter::getMyselfsync()
	{
		return myself;
	}

	void DataCenter::resetMyself(std::shared_ptr<bite_im::GetUserInfoRsp> resp)
	{
		if (myself == nullptr) {
			myself = new UserInfo();
		}
		const bite_im::UserInfo& userInfo = resp->userInfo();
		myself->load(userInfo);
	}

} //end namespace model