#include "updater.h"

#include <QHBoxLayout>
#include <QFormLayout>
#include <QTimer>
#include <QLabel>
#include <QApplication>
#include <QPushButton>
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QJsonObject>
#include <QPointer>

#include <widgets/widgetsfactory.h>
#include <utils/widgetutils.h>
#include <utils/utils.h>
#include <vtextedit/networkutils.h>

using namespace vnotex;

Updater::Updater(QWidget *p_parent)
    : Dialog(p_parent)
{
    setupUI();
}

void Updater::setupUI()
{
    auto mainWidget = new QWidget(this);
    setCentralWidget(mainWidget);

    auto mainLayout = WidgetsFactory::createFormLayout(mainWidget);

    mainLayout->addRow(tr("Version:"), new QLabel(qApp->applicationVersion(), mainWidget));

    m_latestVersionLabel = new QLabel(tr("Fetching information..."), mainWidget);
    mainLayout->addRow(tr("Latest version:"), m_latestVersionLabel);

    setDialogButtonBox(QDialogButtonBox::Ok);

    {
        auto btnBox = getDialogButtonBox();
        auto viewBtn = btnBox->addButton(tr("View Releases"), QDialogButtonBox::AcceptRole);
        connect(viewBtn, &QPushButton::clicked,
                this, []() {
                    WidgetUtils::openUrlByDesktop(QUrl("https://github.com/vnotex/vnote/releases"));
                });
    }

    setWindowTitle(tr("Check for Updates"));
}

void Updater::showEvent(QShowEvent *p_event)
{
    Dialog::showEvent(p_event);

    QTimer::singleShot(1000, this, &Updater::start);
}

void Updater::start()
{
    checkForUpdates(this, [this](bool p_hasUpdate, const QString &p_version, const QString &p_errMsg) {
                Q_UNUSED(p_hasUpdate);
                if (p_version.isEmpty()) {
                    setInformationText(tr("Failed to fetch information (%1).").arg(p_errMsg), InformationLevel::Warning);
                    m_latestVersionLabel->setText("");
                } else {
                    clearInformationText();
                    m_latestVersionLabel->setText(p_version);
                }
            });
}

void Updater::checkForUpdates(QObject *p_receiver, const std::function<void(bool, const QString &, const QString &)> &p_callback)
{
    QPointer<QObject> receiver(p_receiver);

    // Will delete it in the callback.
    auto mgr = new QNetworkAccessManager();
    connect(mgr, &QNetworkAccessManager::finished,
            mgr, [mgr, receiver, p_callback](QNetworkReply *p_reply) {
                bool hasUpdate = false;
                QString version;
                QString errMsg;
                if (p_reply->error() != QNetworkReply::NoError) {
                    errMsg = vte::NetworkUtils::networkErrorStr(p_reply->error());
                } else {
                    auto obj = Utils::fromJsonString(p_reply->readAll());
                    version = obj["tag_name"].toString();
                    if (version.startsWith('v')) {
                        version = version.mid(1);
                    }
                    hasUpdate = version != qApp->applicationVersion();
                }

                if (receiver) {
                    p_callback(hasUpdate, version, errMsg);
                }
                p_reply->deleteLater();
                mgr->deleteLater();
            });

    mgr->get(vte::NetworkUtils::networkRequest(QUrl("https://api.github.com/repos/vnotex/vnote/releases/latest")));
}