#include "NotificationChecker.h"

#include <QJsonDocument>
#include <QJsonObject>
#include <QJsonArray>
#include <QDebug>

#include "Env.h"
#include "net/Download.h"


NotificationChecker::NotificationChecker(QObject *parent)
    : QObject(parent)
{
}

void NotificationChecker::setNotificationsUrl(const QUrl &notificationsUrl)
{
    m_notificationsUrl = notificationsUrl;
}

void NotificationChecker::setApplicationChannel(QString channel)
{
    m_appVersionChannel = channel;
}

void NotificationChecker::setApplicationFullVersion(QString version)
{
    m_appFullVersion = version;
}

void NotificationChecker::setApplicationPlatform(QString platform)
{
    m_appPlatform = platform;
}

QList<NotificationChecker::NotificationEntry> NotificationChecker::notificationEntries() const
{
    return m_entries;
}

void NotificationChecker::checkForNotifications()
{
    if (!m_notificationsUrl.isValid())
    {
        qCritical() << "Failed to check for notifications. No notifications URL set."
                     << "If you'd like to use MultiMC's notification system, please pass the "
                        "URL to CMake at compile time.";
        return;
    }
    if (m_checkJob)
    {
        return;
    }
    m_checkJob.reset(new NetJob("Checking for notifications"));
    auto entry = ENV.metacache()->resolveEntry("root", "notifications.json");
    entry->setStale(true);
    m_checkJob->addNetAction(m_download = Net::Download::makeCached(m_notificationsUrl, entry));
    connect(m_download.get(), &Net::Download::succeeded, this, &NotificationChecker::downloadSucceeded);
    m_checkJob->start();
}

void NotificationChecker::downloadSucceeded(int)
{
    m_entries.clear();

    QFile file(m_download->getTargetFilepath());
    if (file.open(QFile::ReadOnly))
    {
        QJsonArray root = QJsonDocument::fromJson(file.readAll()).array();
        for (auto it = root.begin(); it != root.end(); ++it)
        {
            QJsonObject obj = (*it).toObject();
            NotificationEntry entry;
            entry.id = obj.value("id").toDouble();
            entry.message = obj.value("message").toString();
            entry.channel = obj.value("channel").toString();
            entry.platform = obj.value("platform").toString();
            entry.from = obj.value("from").toString();
            entry.to = obj.value("to").toString();
            const QString type = obj.value("type").toString("critical");
            if (type == "critical")
            {
                entry.type = NotificationEntry::Critical;
            }
            else if (type == "warning")
            {
                entry.type = NotificationEntry::Warning;
            }
            else if (type == "information")
            {
                entry.type = NotificationEntry::Information;
            }
            if(entryApplies(entry))
                m_entries.append(entry);
        }
    }

    m_checkJob.reset();

    emit notificationCheckFinished();
}

bool versionLessThan(const QString &v1, const QString &v2)
{
    QStringList l1 = v1.split('.');
    QStringList l2 = v2.split('.');
    while (!l1.isEmpty() && !l2.isEmpty())
    {
        int one = l1.isEmpty() ? 0 : l1.takeFirst().toInt();
        int two = l2.isEmpty() ? 0 : l2.takeFirst().toInt();
        if (one != two)
        {
            return one < two;
        }
    }
    return false;
}

bool NotificationChecker::entryApplies(const NotificationChecker::NotificationEntry& entry) const
{
    bool channelApplies = entry.channel.isEmpty() || entry.channel == m_appVersionChannel;
    bool platformApplies = entry.platform.isEmpty() || entry.platform == m_appPlatform;
    bool fromApplies =
        entry.from.isEmpty() || entry.from == m_appFullVersion || !versionLessThan(m_appFullVersion, entry.from);
    bool toApplies =
        entry.to.isEmpty() || entry.to == m_appFullVersion || !versionLessThan(entry.to, m_appFullVersion);
    return channelApplies && platformApplies && fromApplies && toApplies;
}
