// Copyright (c) 2012 - 2026 kio@little-bat.de
// BSD-2-Clause license
// https://opensource.org/licenses/BSD-2-Clause

#include "CheckUpdate.h"
#include "Application.h"
#include "Qt/Settings.h"
#include "Templates/Array.h"
#include "cpp/cppthreads.h"
#include "unix/FD.h"
#include "unix/files.h"
#include "version.h"
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QObject>
#include <QSettings>
#include <QString>
#include <QStringList>


namespace zxsp
{

// extern
void checkUpdate(bool verbose)
{
	new CheckUpdate(appl, verbose); // will self-destruct
	settings.setValue(key_check_update_timestamp, now() + 12 * 60 * 60);
}


// ---------------------------------------------------------------
// Implementation:


CheckUpdate::CheckUpdate(QObject* parent, bool verbose) :
	QObject(parent),
	verbose(verbose),
	state(dl_filelist),
	filename(nullptr),
	network_manager(nullptr),
	reply(nullptr),
	request()
{
	request.setUrl(QUrl(catstr(check_update_url, APPL_VERSION_STR)));
	network_manager = new QNetworkAccessManager(this);
	connect(network_manager, &QNetworkAccessManager::finished, this, &CheckUpdate::slot_finished);
	reply = network_manager->get(request);
}


CheckUpdate::~CheckUpdate()
{
	delete[] filename;
	filename = nullptr;
}


// private slot
void CheckUpdate::slot_finished()
{
	xlogIn("CheckUpdate::slotFinished");

	reply->deleteLater();

	if (reply->error() != QNetworkReply::NoError)
	{
		if (verbose) showWarning("CheckUpdate: error = %s", reply->errorString().toUtf8().data());
		else xlogline("CheckUpdate: error = %s", reply->errorString().toUtf8().data());
		goto x;
	}

	{
		QVariant qv = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
		if (QMetaType::Type(qv.type()) == QMetaType::QUrl)
		{
			QUrl url = request.url().resolved(qv.toUrl());
			xlogline("CheckUpdate: redirected to %s", url.toString().toUtf8().data());
			request.setUrl(QUrl(url));
			reply = network_manager->get(request);
			// state = state; dl_filelist or dl_file: both may be redirected
			return;
		}
	}

	{
		uint httpstatuscode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toUInt();
		if (httpstatuscode != 200u /*HTTP_RESPONSE_OK*/)
		{
			if (verbose) showWarning("CheckUpdate: http status = %u", httpstatuscode);
			else xlogline("CheckUpdate: http status = %u", httpstatuscode);
			goto x;
		}
	}

	if (!reply->isReadable())
	{
		if (verbose) showWarning("CheckUpdate: reply not readable");
		else xlogline("CheckUpdate: reply not readable");
		goto x;
	}

	try
	{
		switch (state)
		{
		case dl_filelist: // step 1: retrieve download url completed
		{
			QByteArray data = reply->readAll();
			if (data.isEmpty()) goto x; // empty reply => no new version

			cstr url = substr(data.data(), data.data() + data.count());
			if (*url == '<') goto x; // html error message...

			filename = newcopy(last_component_from_path(url));
			xlogline("CheckUpdate: download new version: %s", filename);
			fd.open_file_n(catstr("~/Desktop/", filename));

			request.setUrl(QUrl(url));
			reply = network_manager->get(request);
			connect(reply, &QNetworkReply::readyRead, this, [this]() {
				if (!fd.is_valid()) return;
				QByteArray data = reply->readAll();
				fd.write_bytes(data.data(), uint(data.count()));
			});
			state = dl_file; // state := download file
			return;			 // -> slotReadyRead and slotFinished will be called (again)
		}
		case dl_file: // step 2: download file completed
		{
			QByteArray data = reply->readAll();
			fd.write_bytes(data.data_ptr(), uint(data.count()));

			showInfo("A new version of zxsp has been placed on your desktop:\n\n\"%s\"", filename);
			xlogline("CheckUpdate: New version of zxsp received successfully");
			state = dl_idle;
			break;
		}
		default: break;
		}
	}
	catch (AnyError& e)
	{
		if (verbose) showWarning("CheckUpdate: %s", e.what());
		else xlogline("CheckUpdate: %s", e.what());
	}


x:
	deleteLater(); // self-destruct
}

} // namespace zxsp