/* Copyright (C) 2015
 * swift project Community / Contributors
 *
 * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
 * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
 * including this file, may be copied, modified, propagated, or distributed except according to the terms
 * contained in the LICENSE file.
 */

#include "blackmisc/network/urllist.h"
#include "blackmisc/network/networkutils.h"
#include "blackmisc/math/mathutils.h"
#include "blackmisc/stringutils.h"

#include <QtGlobal>
#include <tuple>

using namespace BlackMisc::Math;

namespace BlackMisc
{
    namespace Network
    {
        CUrlList::CUrlList() { }

        CUrlList::CUrlList(const CSequence<CUrl> &other) :
            CSequence<CUrl>(other)
        { }

        CUrlList::CUrlList(const QStringList &listOfUrls, bool removeDuplicates)
        {
            QStringList urlList(listOfUrls);
            if (removeDuplicates) { urlList.removeDuplicates(); }
            for (const QString &url : urlList)
            {
                this->push_back(CUrl(url));
            }
        }

        CUrl CUrlList::getRandomUrl() const
        {
            if (this->isEmpty()) { return CUrl(); }
            if (this->size() == 1) { return this->front();}
            int i = CMathUtils::randomInteger(0, this->size() - 1);
            return (*this)[i];
        }

        CUrl CUrlList::getRandomWorkingUrl(int maxTrials) const
        {
            if (this->isEmpty()) { return CUrl(); }
            if (maxTrials < 1) { return CUrl();}
            CUrlList trials;

            for (int t = 0; t < maxTrials && t < this->size(); t++)
            {
                CUrl url(getRandomWithout(trials));
                trials.push_back(url);
                QString message;
                if (CNetworkUtils::canConnect(url, message)) { return url; }
            }
            return CUrl();
        }

        CUrl CUrlList::getRandomWithout(const CUrlList &exclude) const
        {
            CUrlList copy(*this);
            copy.removeIfIn(exclude);
            if (copy.isEmpty()) { return CUrl(); }
            return copy.getRandomUrl();
        }

        CUrlList CUrlList::withAppendedPath(const QString &path) const
        {
            if (path.isEmpty() || this->isEmpty()) { return (*this); }
            CUrlList urls;
            for (const CUrl &url : (*this))
            {
                urls.push_back(url.withAppendedPath(path));
            }
            return urls;
        }

        CUrlList CUrlList::findByHost(const QString &host, Qt::CaseSensitivity cs) const
        {
            CUrlList result;
            if (host.isEmpty() || this->isEmpty()) { return result; }
            for (const CUrl &url : *this)
            {
                if (stringCompare(url.getHost(), host, cs))
                {
                    result.push_back(url);
                }
            }
            return result;
        }

        QString CUrlList::convertToQString(const QString &separator, bool i18n) const
        {
            const QStringList sl(toStringList(i18n));
            return sl.join(separator);
        }

        CUrlList CUrlList::getWithoutDuplicates() const
        {
            if (this->size() < 2) { return (*this); }
            CUrlList withoutDuplicates;
            for (const CUrl &url : (*this))
            {
                withoutDuplicates.replaceOrAdd(url, url);
            }
            return withoutDuplicates;
        }

        int CUrlList::removeDuplicates()
        {
            if (this->size() < 2) { return 0; }
            const CUrlList withoutDuplicates(getWithoutDuplicates());
            if (this->size() == withoutDuplicates.size()) { return 0; }
            int r = this->size() - withoutDuplicates.size();
            (*this) = withoutDuplicates;
            return r;
        }

        CFailoverUrlList::CFailoverUrlList(int maxTrials) :
            m_maxTrials(maxTrials)
        { }

        CFailoverUrlList::CFailoverUrlList(const QStringList &listOfUrls, int maxTrials) :
            CUrlList(listOfUrls), m_maxTrials(maxTrials)
        { }

        CFailoverUrlList::CFailoverUrlList(const CSequence<CUrl> &other, int maxTrials) :
            CUrlList(other), m_maxTrials(maxTrials)
        { }

        CFailoverUrlList::CFailoverUrlList(const CUrlList &urlIst) :
            CUrlList(urlIst)
        { }

        CUrlList CFailoverUrlList::getWithoutFailed() const
        {
            CUrlList urls(*this);
            urls.removeIfIn(m_failedUrls);
            return urls;
        }

        bool CFailoverUrlList::addFailedUrl(const CUrl &failedUrl)
        {
            Q_ASSERT_X(!failedUrl.isEmpty(), Q_FUNC_INFO, "empty URL as failed");
            m_failedUrls.push_back(failedUrl);
            return hasMoreUrlsToTry();
        }

        bool CFailoverUrlList::addFailedUrls(const CUrlList &failedUrls)
        {
            m_failedUrls.push_back(failedUrls);
            return hasMoreUrlsToTry();
        }

        bool CFailoverUrlList::addFailedHost(const CUrl &failedUrl)
        {
            Q_ASSERT_X(!failedUrl.isEmpty(), Q_FUNC_INFO, "empty URL as failed");
            const QString host = failedUrl.getHost();
            return CFailoverUrlList::addFailedHost(host);
        }

        bool CFailoverUrlList::addFailedHost(const QString &host, Qt::CaseSensitivity cs)
        {
            if (host.isEmpty()) { return this->hasMoreUrlsToTry(); }
            const CUrlList failedUrls = this->findByHost(host, cs);
            return addFailedUrls(failedUrls);
        }

        bool CFailoverUrlList::hasMoreUrlsToTry() const
        {
            return this->numberOfStillValidUrls() > 0;
        }

        int CFailoverUrlList::numberOfStillValidUrls() const
        {
            if (this->isEmpty()) { return 0; }
            if (m_failedUrls.size() >= m_maxTrials) { return 0; }
            const int trailsLeft1 = qMax(m_maxTrials - m_failedUrls.size(), 0);
            const int trailsLeft2 = qMax(this->size() - m_failedUrls.size(), 0);
            return qMin(trailsLeft1, trailsLeft2);
        }

        CUrl CFailoverUrlList::obtainNextWorkingUrl(bool random, int connectTimeoutMs)
        {
            if (!hasMoreUrlsToTry()) { return CUrl(); }
            const CUrl url(this->obtainNextUrlWithout(random, m_failedUrls));
            QString msg;
            if (CNetworkUtils::canConnect(url, msg, connectTimeoutMs)) { return url; }
            if (addFailedUrl(url))
            {
                if (!msg.isEmpty())
                {
                    m_errorMsgs.append(QString("URL: %1 error: %2").arg(url.toQString(), msg));
                }
                return obtainNextWorkingUrl(random, connectTimeoutMs);
            }
            return CUrl();
        }

        CUrl CFailoverUrlList::obtainNextUrl(bool randomStart)
        {
            if (this->isEmpty()) { return CUrl(); }
            if (this->size() == 1) { return this->front();}
            if (m_currentIndexDistributedLoad < 0)
            {
                // random start point
                m_currentIndexDistributedLoad =  randomStart ?
                                                 CMathUtils::randomInteger(0, this->size() - 1) :
                                                 0;
            }
            else
            {
                m_currentIndexDistributedLoad++;
                if (m_currentIndexDistributedLoad >= this->size())
                {
                    m_currentIndexDistributedLoad = 0;
                }
            }
            return (*this)[m_currentIndexDistributedLoad];
        }

        CUrl CFailoverUrlList::obtainNextUrlWithout(bool randomStart, const CUrlList &exclude) const
        {
            CFailoverUrlList copy(*this);
            copy.removeIfIn(exclude);
            if (copy.isEmpty()) { return CUrl(); }
            return copy.obtainNextUrl(randomStart);
        }

        void CFailoverUrlList::reset(int maxTrials)
        {
            m_failedUrls.clear();
            if (maxTrials >= 0) { m_maxTrials = maxTrials; }
        }
    } // namespace
} // namespace