diff --git a/src/generator/generator.cpp b/src/generator/generator.cpp
index 57382e3..6e79ce5 100644
--- a/src/generator/generator.cpp
+++ b/src/generator/generator.cpp
@@ -1,879 +1,883 @@
 /*
     Copyright (C) 2020 Volker Krause <vkrause@kde.org>
 
     This program is free software; you can redistribute it and/or modify it
     under the terms of the GNU Library General Public License as published by
     the Free Software Foundation; either version 2 of the License, or (at your
     option) any later version.
 
     This program is distributed in the hope that it will be useful, but WITHOUT
     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
     License for more details.
 
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
 #include "indexeddatatable.h"
 #include "lineinfo.h"
 
 #include "../lib/datatypes/linecompare_p.h"
 
 #include <osm/xmlparser.h>
 #include <osm/ztile.h>
 
 #include <wikidataquery.h>
 #include <wikidataquerymanager.h>
 
 #include <QColor>
 #include <QCommandLineParser>
 #include <QCoreApplication>
 #include <QDebug>
 #include <QFile>
 
 #include <set>
 
 namespace wd = Wikidata;
 
 enum {
     MaxLogoFileSize = 10000, // bytes
 };
 
 static constexpr const auto MaxLogoAspectRatio = 2.75;
 static constexpr const auto MinLogoAspectRatio = 0.45; // Shanghai Metro is the extreme still valid case with 0.5
 
 static constexpr const auto MinTileCoverage = 0.1;
 
 static bool isCompatibleMode(LineInfo::Mode lhs, LineInfo::Mode rhs)
 {
     if (lhs == LineInfo::Unknown || rhs == LineInfo::Unknown) {
         return true;
     }
     if ((lhs == LineInfo::LocalTrain && rhs == LineInfo::RapidTransit) || (lhs == LineInfo::RapidTransit && rhs == LineInfo::LocalTrain)) {
         return true;
     }
 
     return lhs == rhs;
 }
 
 static bool isSameLine(const LineInfo &lhs, const LineInfo &rhs)
 {
     return isCompatibleMode(lhs.mode, rhs.mode)
         && KPublicTransport::Internal::isSameLineName(lhs.name, rhs.name, KPublicTransport::Internal::StrictCompare);
 }
 
 class Generator {
 public:
     void processOSMData(OSM::DataSet &&dataSet);
     void augmentFromWikidata();
     void applyWikidataResults(std::vector<wd::Item> &&entities);
     void augmentProductsFromWikidata();
     void applyWikidataProductResults(std::vector<wd::Item> &&entities);
     void applyWikidataProductResults();
     void verifyImages();
     void verifyImageMetaData(std::vector<wd::Image> &&images);
     void verifyImageMetaData(QStringList &logos);
     void verifyImageMetaData();
 
     void generateQuadTree();
     bool resolveOneBottomUpConflict();
     void writeCode();
 
     void insertToBucket(OSM::ZTile tile, std::size_t lineIdx);
 
     QIODevice *out = nullptr;
     std::vector<LineInfo> lines;
     WikidataQueryManager *m_wdMgr = new WikidataQueryManager(QCoreApplication::instance());
     std::set<wd::Q> wdPartOfIds;
     std::map<wd::Q, wd::Item> wdItems;
     std::map<QString, wd::Image> wdImages;
 
     std::map<OSM::ZTile, std::vector<size_t>> zQuadTree;
 };
 
 void Generator::insertToBucket(OSM::ZTile tile, std::size_t lineIdx)
 {
     auto &bucket = zQuadTree[tile];
     if (std::find(bucket.begin(), bucket.end(), lineIdx) == bucket.end()) {
         bucket.push_back(lineIdx);
     } else {
         // all tree transforms below should not create duplicates
         assert(false);
     }
 }
 
 void Generator::processOSMData(OSM::DataSet &&dataSet)
 {
     qDebug() << "got" << dataSet.relations.size() << "relations from OSM";
     // expand multi-line relations
     for (auto it = dataSet.relations.begin(); it != dataSet.relations.end();) {
         const auto ref = OSM::tagValue(*it, QLatin1String("ref"));
         if (!ref.contains(QLatin1Char(';'))) {
             ++it;
             continue;
         }
 
+#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
+        const auto refs = ref.split(QLatin1Char(';'), QString::SkipEmptyParts);
+#else
         const auto refs = ref.split(QLatin1Char(';'), Qt::SkipEmptyParts);
+#endif
         for (const auto &ref : refs) {
             auto rel = *it;
             OSM::setTagValue(rel, QStringLiteral("ref"), ref);
             dataSet.relations.push_back(rel);
         }
         it = dataSet.relations.erase(it);
     }
     qDebug() << "OSM relations after ref split:" << dataSet.relations.size();
 
     // split relations into route_master elements and route elements
     auto splitIt = std::partition(dataSet.relations.begin(), dataSet.relations.end(), [](const auto &rel) {
         return OSM::tagValue(rel, QLatin1String("type")) == QLatin1String("route_master");
     });
     sort(splitIt, dataSet.relations.end());
     const auto routeMasterCount = std::distance(dataSet.relations.begin(), splitIt);
     qDebug() << "  containing" << routeMasterCount << "route masters and" << (dataSet.relations.size() - routeMasterCount) << "routes";
 
     // resolve route masters first, and then consider the remaining routes that have no route_master
     for (auto i = 0; i < routeMasterCount; ++i) {
         auto &rel = dataSet.relations[i];
         auto info = LineInfo::fromRelation(rel);
         if (info.name.isEmpty()) {
             continue;
         }
 
         const auto members = std::move(rel.members); // reference will become invalid once we start to modify below
         for (const auto &mem : members) {
             auto memIt = std::lower_bound(dataSet.relations.begin() + routeMasterCount, dataSet.relations.end(), mem.id);
             if (memIt == dataSet.relations.end() || (*memIt).id != mem.id) {
                 continue;
             }
             LineInfo::merge(info, LineInfo::fromRelation(*memIt));
             dataSet.relations.erase(memIt);
         }
         lines.push_back(std::move(info));
     }
 
     // deal with routes without a route master
     qDebug() << "  " << (dataSet.relations.size() - routeMasterCount) << "dangling routes remaining";
     for (auto it = dataSet.relations.begin() + routeMasterCount; it != dataSet.relations.end(); ++it) {
         auto info = LineInfo::fromRelation(*it);
         if (info.name.isEmpty()) {
             continue;
         }
         lines.push_back(std::move(info));
     }
     qDebug() << "merged lines:" << lines.size();
 
     // filter useless lines - ie. those that don't contain useful information and have no wikidata id to fill the missing gaps
     lines.erase(std::remove_if(lines.begin(), lines.end(), [](const auto &info) {
         return !LineInfo::isUseful(info) && !info.wdId.isValid();
     }), lines.end());
     qDebug() << "lines after filtering OSM data:" << lines.size();
 
     // check for uniqueness of (bbox, name) - would break indexing and can happen for lines without a route_master relation
     // we assume those to belong together as well and thus merge them to a single line
     for (auto lit = lines.begin(); lit != lines.end(); ++lit) {
         // a merge pass can increase the bbox to include more elements that we previously missed
         // so do this as long as we find things
         while (true) {
             auto dupIt = std::partition(lit + 1, lines.end(), [lit](const auto &rhs) {
                 return !isSameLine(*lit, rhs) || !OSM::intersects((*lit).bbox, rhs.bbox);
             });
             if (dupIt == lines.end()) {
                 break;
             }
 
             for (auto it = dupIt; it != lines.end(); ++it) {
                 LineInfo::merge(*lit, *it);
             }
             lines.erase(dupIt, lines.end());
         }
     }
     qDebug() << "lines after bbox merge:" << lines.size();
 
     augmentFromWikidata();
 }
 
 void Generator::augmentFromWikidata()
 {
     // sort to maximize cache hits of the batches wikidata queries
     std::sort(lines.begin(), lines.end(), [](const auto &lhs, const auto &rhs) {
         return lhs.wdId < rhs.wdId;
     });
     std::vector<wd::Q> wdIds;
     for (const auto &r: lines) {
         if (r.wdId.isValid()) {
             wdIds.push_back(r.wdId);
         }
     }
     wdIds.erase(std::unique(wdIds.begin(), wdIds.end()), wdIds.end());
     qDebug() << "Retrieving" << wdIds.size() << "items from Wikidata";
 
     auto query = new WikidataEntitiesQuery(m_wdMgr);
     query->setItems(std::move(wdIds));
     QObject::connect(query, &WikidataEntitiesQuery::partialResult, [this](auto query) { applyWikidataResults(std::move(query->takeResult())); });
     QObject::connect(query, &WikidataQuery::finished, [this, query]() mutable {
         if (query->error() != WikidataQuery::NoError) {
             qCritical() << "Wikidata query failed";
             QCoreApplication::exit(1);
             return;
         }
 
         augmentProductsFromWikidata();
     });
     m_wdMgr->execute(query);
 }
 
 static struct {
     wd::Q id;
     LineInfo::Mode mode;
 } const wd_type_to_mode_map[] = {
     { wd::Q(1412403), LineInfo::RapidTransit }, // commuter rail
     { wd::Q(1192191), LineInfo::RapidTransit }, // airport rail link
     { wd::Q(50331459), LineInfo::RapidTransit }, // S-Bahn line
     { wd::Q(95723), LineInfo::RapidTransit }, // S-Bahn
     { wd::Q(129172), LineInfo::LongDistance }, // ICE
     { wd::Q(15145593), LineInfo::Tram }, // tram line
     { wd::Q(2572054), LineInfo::RapidTransit }, // Transilien (multiple variants)
     { wd::Q(732778), LineInfo::RapidTransit }, // Transilien
     { wd::Q(2571458), LineInfo::RapidTransit }, // Transilien
     { wd::Q(2571977), LineInfo::RapidTransit }, // Transilien
     { wd::Q(373725), LineInfo::RapidTransit }, // Transilien
     { wd::Q(858485), LineInfo::LongDistance }, // high speed railway line
     { wd::Q(2138247), LineInfo::LocalTrain }, // Regional-Express
     { wd::Q(515449), LineInfo::LocalTrain }, // Regionalbahn
 };
 
 static LineInfo::Mode modeFromWikidataType(wd::Q type)
 {
     LineInfo::Mode mode = LineInfo::Unknown;
     for (const auto &modeMap : wd_type_to_mode_map) {
         if (type == modeMap.id) {
             mode = std::max(modeMap.mode, mode);
         }
     }
     return mode;
 }
 
 static const wd::Q wd_excluded_types[] {
     wd::Q(43229), // organization
     wd::Q(740752), // transport company
     wd::Q(928830), // metro station
     wd::Q(4830453), // business
     wd::Q(7835189), // transit district
     wd::Q(249556), // railway company
     wd::Q(17377208), // train operating company
     wd::Q(138825), // children's railway (yes, really...)
     wd::Q(1144661), // amusement ride
     wd::Q(420962), // heritage railway
 };
 
 static bool isExcludedWikidataType(wd::Q type)
 {
     return std::find(std::begin(wd_excluded_types), std::end(wd_excluded_types), type) != std::end(wd_excluded_types);
 }
 
 static const wd::Q wd_product_types[] {
     wd::Q(5503), // rapid transit
     wd::Q(95723), // S-Bahn
     wd::Q(15640053), // tram system
     wd::Q(1412403), // commuter rail
     wd::Q(2140646), // Stadtbahn
     wd::Q(1268865), // light rail
 };
 
 static bool isWikidataProductType(wd::Q type)
 {
     return std::find(std::begin(wd_product_types), std::end(wd_product_types), type) != std::end(wd_product_types);
 }
 
 static const wd::Q wd_recursive_product_types[] = {
     wd::Q(95723), // S-Bahn
     wd::Q(1054782), // Cercanías
 };
 
 void Generator::applyWikidataResults(std::vector<wd::Item> &&items)
 {
     for (auto &item : items) {
         auto rit = std::lower_bound(lines.begin(), lines.end(), item.id(), [](const LineInfo &lhs, wd::Q rhs) {
             return lhs.wdId < rhs;
         });
         // wikidata line elements shouldn't occur for multiple lines, but in some cases
         // OSM points to product or network elements instead, and those can occur once per line
         for (; rit != lines.end() && (*rit).wdId == item.id(); ++rit) {
             // check if this is a plausible type
             const auto instancesOf = item.values<wd::Q>(wd::P::instanceOf);
             bool found = false;
             LineInfo::Mode mode = LineInfo::Unknown;
             for (const auto &instanceOf : instancesOf) {
                 if (isExcludedWikidataType(instanceOf)) {
                     qWarning() << "Suspicious WD types:" << (*rit) << instancesOf;
                     found = true;
                 }
                 mode = std::max(mode, modeFromWikidataType(instanceOf));
 
                 if (isWikidataProductType(instanceOf)) { // wikidata link in OSM is pointing to the product, not the line it seems
                     wdPartOfIds.insert(item.id());
                     (*rit).wdProducts.push_back(item.id());
                 }
             }
             if (found) {
                 break;
             }
 
             // collect possible product types
             const auto partOfIds = item.values<wd::Q>(wd::P::partOf);
             for (const auto &id : partOfIds) {
                 wdPartOfIds.insert(id);
                 (*rit).wdProducts.push_back(id);
 
                 mode = std::max(mode, modeFromWikidataType(id));
             }
 
             // merge information
             const auto color = item.value<QColor>(wd::P(465));
             if ((*rit).color.isValid() && color.isValid() && (*rit).color != color) {
                 qWarning() << "OSM/WD color conflict:" << (*rit) << color.name();
             } else if (color.isValid()) {
                 (*rit).color = color;
             }
             const auto logos = item.values<QString>(wd::P::logoImage);
             for (const auto &logo : logos) {
                 if (!logo.isEmpty() && !(*rit).lineLogos.contains(logo)) {
                     (*rit).lineLogos.push_back(logo);
                 }
             }
             if (!isCompatibleMode((*rit).mode, mode)) {
                 qWarning() << "OSM/WD mode conflict:" << (*rit) << mode;
             }
             (*rit).mode = std::max((*rit).mode, mode);
         }
 
         wdItems[item.id()] = std::move(item);
     }
 }
 
 void Generator::augmentProductsFromWikidata()
 {
     for (const auto &t : wd_recursive_product_types) { // should all be already in there, but let's make sure so we don't have to check again below
         wdPartOfIds.insert(t);
     }
     std::vector<wd::Q> wdIds;
     for (const auto &id: wdPartOfIds) {
         if (id.isValid() && wdItems.find(id) == wdItems.end()) {
             wdIds.push_back(id);
         }
     }
     qDebug() << "Retrieving" << wdIds.size() << "product items from Wikidata";
 
     auto query = new WikidataEntitiesQuery(m_wdMgr);
     query->setItems(std::move(wdIds));
     QObject::connect(query, &WikidataEntitiesQuery::partialResult, [this](auto query) { applyWikidataProductResults(std::move(query->takeResult())); });
     QObject::connect(query, &WikidataQuery::finished, [this, query]() mutable {
         if (query->error() != WikidataQuery::NoError) {
             qCritical() << "Wikidata product query failed";
             QCoreApplication::exit(1);
             return;
         }
 
         applyWikidataProductResults();
         verifyImages();
     });
     m_wdMgr->execute(query);
 }
 
 void Generator::applyWikidataProductResults(std::vector<wd::Item> &&items)
 {
     for (auto &item : items) {
         wdItems[item.id()] = std::move(item);
     }
 }
 
 void Generator::applyWikidataProductResults()
 {
     for (const auto &id : wdPartOfIds) {
         const auto item = wdItems[id];
         // check if this is a plausible type
         const auto instancesOf = item.values<wd::Q>(wd::P::instanceOf);
         LineInfo::Mode mode = LineInfo::Unknown;
         bool found = false;
         for (const auto &instanceOf : instancesOf) {
             if (isWikidataProductType(instanceOf)) {
                 found = true;
             }
             mode = std::max(mode, modeFromWikidataType(instanceOf));
         }
         if (!found && !std::all_of(instancesOf.begin(), instancesOf.end(), isExcludedWikidataType)) {
             qDebug() << "Product" << item.id() << "is of unknown type " << instancesOf;
         }
         if (!found) {
             continue;
         }
 
         // retrieve logo and find the lines this is for
         auto logoNames = item.values<QString>(wd::P::logoImage);
         // check if this is a type we should recurse on for more logo candidates
         for (const auto &instanceOf : instancesOf) {
             if (std::find(std::begin(wd_recursive_product_types), std::end(wd_recursive_product_types), instanceOf) == std::end(wd_recursive_product_types)) {
                 continue;
             }
             const auto logos = wdItems[instanceOf].values<QString>(wd::P::logoImage);
             std::copy(logos.begin(), logos.end(), std::back_inserter(logoNames));
         }
 
         if (logoNames.empty() && mode == LineInfo::Unknown) {
             continue;
         }
         for (auto &line : lines) {
             if (std::find(line.wdProducts.begin(), line.wdProducts.end(), item.id()) == line.wdProducts.end()) {
                 continue;
             }
 
             if (line.mode == LineInfo::Unknown) {
                 line.mode = mode;
             }
 
             std::copy(logoNames.begin(), logoNames.end(), std::back_inserter(line.productLogos));
         }
     }
 }
 
 void Generator::verifyImages()
 {
     std::vector<QString> imageIds;
     for (const auto &r: lines) {
         if (!LineInfo::isUseful(r)) {
             continue;
         }
         std::copy(r.lineLogos.begin(), r.lineLogos.end(), std::back_inserter(imageIds));
         std::copy(r.productLogos.begin(), r.productLogos.end(), std::back_inserter(imageIds));
     }
     std::sort(imageIds.begin(), imageIds.end());
     imageIds.erase(std::unique(imageIds.begin(), imageIds.end()), imageIds.end());
     imageIds.erase(std::remove(imageIds.begin(), imageIds.end(), QString()), imageIds.end());
     qDebug() << "Verifying" << imageIds.size() << "images" << imageIds;
 
     auto query = new WikidataImageMetadataQuery(m_wdMgr);
     query->setImages(std::move(imageIds));
     QObject::connect(query, &WikidataImageMetadataQuery::partialResult, [this](auto query) { verifyImageMetaData(std::move(query->takeResult())); });
     QObject::connect(query, &WikidataQuery::finished, [this, query]() mutable {
         if (query->error() != WikidataQuery::NoError) {
             qCritical() << "Wikidata image metadata query failed";
             QCoreApplication::exit(1);
             return;
         }
         verifyImageMetaData();
 
         // filter lines still missing data
         lines.erase(std::remove_if(lines.begin(), lines.end(), [](const auto &info) {
             if (!LineInfo::isUseful(info)) {
                 qDebug() << "dropping" << info;
             }
             return !LineInfo::isUseful(info);
         }), lines.end());
         qDebug() << "lines after Wikidata filtering:" << lines.size();
 
         generateQuadTree();
     });
     m_wdMgr->execute(query);
 }
 
 void Generator::verifyImageMetaData(std::vector<wd::Image> &&images)
 {
     const QStringList valid_licenses({
         QStringLiteral("cc0"),
         QStringLiteral("public domain"),
     });
 
     for (auto &image : images) {
         const auto name = image.name();
         const auto fileSize = image.fileSize();
         if (fileSize > MaxLogoFileSize) {
             qWarning() << "not using logo" << name << "due to file size:" << fileSize;
             continue;
         }
 
         const auto aspectRatio = (double)image.width() / (double)image.height();
         if (aspectRatio > MaxLogoAspectRatio || aspectRatio < MinLogoAspectRatio) {
             qWarning() << "not using logo" << name << "due to aspect ratio:" << aspectRatio;
             continue;
         }
 
         const auto mt = image.mimeType();
         if (mt != QLatin1String("image/svg+xml") && mt != QLatin1String("image/png")) {
             qWarning() << "not using logo" << name << "due to mimetype:" << mt;
             continue;
         }
 
         const auto lic = image.license();
         if (!valid_licenses.contains(lic, Qt::CaseInsensitive)) {
             qWarning() << "not using logo" << name << "due to license:" << lic;
             continue;
         }
 
         wdImages[name] = std::move(image);
    }
    images.clear();
 }
 
 void Generator::verifyImageMetaData(QStringList &logos)
 {
     logos.erase(std::remove_if(logos.begin(), logos.end(), [this](const auto &logo) {
         return wdImages.find(logo) == wdImages.end();
     }), logos.end());
 
     if (logos.size() <= 1) {
         return;
     }
 
     // TODO sort by best aspect ratio/size
     qDebug() << "multiple logos available:" << logos;
 }
 
 void Generator::verifyImageMetaData()
 {
     for (auto &line : lines) {
         verifyImageMetaData(line.lineLogos);
         if (!line.lineLogos.empty() && line.productLogos.size() > 1) {
             line.productLogos.erase(std::remove(line.productLogos.begin(), line.productLogos.end(), line.lineLogos[0]), line.productLogos.end());
         }
         verifyImageMetaData(line.productLogos);
     }
 }
 
 void Generator::generateQuadTree()
 {
     // order lines by OSM id, to increase output stability
     std::sort(lines.begin(), lines.end(), [](const auto &lhs, const auto &rhs) { return lhs.relId < rhs.relId; });
 
     // initialize quad tree by smallest single tile containing the entire line bbox
     for (auto lineIt = lines.begin(); lineIt != lines.end(); ++lineIt) {
         insertToBucket(OSM::ztileFromBoundingBox((*lineIt).bbox), std::distance(lines.begin(), lineIt));
     }
     qDebug() << "initial tiles:" << zQuadTree.size();
 
     // collision resolution
     // this is done in two steps: bottom-up and top-down
     // bottom-up means that for each tile/line we check if there is a parent tile with a conflicting line, and if so, we
     // propagate that line down to the same level
     // this is done in a rather crude brute-force way, but it gets the job done
     while(resolveOneBottomUpConflict()) {}
     qDebug() << "tiles after bottom-up conflict resolution:" << zQuadTree.size();
 
     // top-down means we look at conflicts inside a given tile, and propagate the conflicting lines down
     for (auto tileIt = zQuadTree.begin(); tileIt != zQuadTree.end(); ++tileIt) {
         if ((*tileIt).second.size() <= 1) {
             continue;
         }
         // check for name collisions
         for (auto lit = (*tileIt).second.end(); lit != (*tileIt).second.begin();) {
             const auto lend = lit;
             const auto firstIdx = (*tileIt).second.front();
             lit = std::partition((*tileIt).second.begin(), lend, [this, firstIdx](const auto &lineIdx) {
                 return !isSameLine(lines[firstIdx], lines[lineIdx]);
             });
 
             // must not happen if isSameLineName(x, x) == true holds
             assert(lit != lend);
 
             if (lit + 1 == lend) { // only a single line with that name
                 continue;
             }
 
             // insert subtiles, if they actually contain the line bbox
             qDebug() << "subdividing" << lines[*lit].name << lines[*lit].bbox << lines[*lit].relId << std::distance(lit, lend) << (*lit) << (*tileIt).first.depth << (*tileIt).first.z;
             for (auto it = lit; it != lend; ++it) {
                 for (auto subtile : (*tileIt).first.quadSplit()) {
                     if (subtile.intersects(lines[*it].bbox)) {
                         insertToBucket(subtile, *it);
                     }
                 }
             }
 
             // remove current entries
             lit = (*tileIt).second.erase(lit, lend);
         }
     }
     qDebug() << "tiles after top-down conflict resolution:" << zQuadTree.size();
 
     // split oversized tiles for what they contain, depsite the name being unique in the dataset we have here
     for (auto tileIt = zQuadTree.begin(); tileIt != zQuadTree.end(); ++tileIt) {
         if ((*tileIt).first.depth == 16) { // below that we need more than 32 bit for z in the quad tree storage
             break;
         }
         for (auto lineIt = (*tileIt).second.begin(); lineIt != (*tileIt).second.end();) {
             // push down elements that actually only occupy a sub-tile
             // this can happen as part of conflict resolution above as well as the splitting below
             int coveredSubTiles = 0;
             for (auto subtile : (*tileIt).first.quadSplit()) {
                 if (subtile.intersects(lines[*lineIt].bbox)) {
                     ++coveredSubTiles;
                 }
             }
 
             // check if the line is too small for the current tile, and if so, split it
             const auto coverage = std::max((double)lines[*lineIt].bbox.width() / (double)(*tileIt).first.boundingBox().width(),
                                            (double)lines[*lineIt].bbox.height() / (double)(*tileIt).first.boundingBox().height());
 
             if (coverage < MinTileCoverage || coveredSubTiles == 1) {
                 qDebug() << "splitting due to small coverage:" << lines[*lineIt] << (*tileIt).first.depth << coverage << coveredSubTiles;
                 for (auto subtile : (*tileIt).first.quadSplit()) {
                     if (subtile.intersects(lines[*lineIt].bbox)) {
                         insertToBucket(subtile, *lineIt);
                     }
                 }
                 lineIt = (*tileIt).second.erase(lineIt);
                 continue;
             }
 
             ++lineIt;
         }
     }
     qDebug() << "tiles after coverage cleanup:" << zQuadTree.size();
 
     // remove empty buckets, and sort the non-empty ones for output stability
     for (auto tileIt = zQuadTree.begin(); tileIt != zQuadTree.end();) {
         if ((*tileIt).second.empty()) {
             tileIt = zQuadTree.erase(tileIt);
         } else {
             std::sort((*tileIt).second.begin(), (*tileIt).second.end(), [this](const auto lhs, const auto rhs) {
                 return lines[lhs].name < lines[rhs].name;
             });
 
             ++tileIt;
         }
     }
     qDebug() << "tiles remaining after cleanup:" << zQuadTree.size();
 
     writeCode();
 }
 
 bool Generator::resolveOneBottomUpConflict()
 {
     for (auto tileIt = zQuadTree.rbegin(); tileIt != zQuadTree.rend(); ++tileIt) {
         for (auto lineIt = (*tileIt).second.begin(); lineIt != (*tileIt).second.end(); ++lineIt) {
             auto parentTile = (*tileIt).first.parent();
             while (parentTile.depth < 32) {
                 const auto parentTileIt = zQuadTree.find(parentTile);
                 if (parentTileIt != zQuadTree.end()) {
                     auto conflictIt = std::find_if((*parentTileIt).second.begin(), (*parentTileIt).second.end(), [this, lineIt](const auto lhs) {
                         return isSameLine(lines[lhs], lines[*lineIt]);
                     });
                     if (conflictIt != (*parentTileIt).second.end()) {
                         qDebug() << "propagating down:" << lines[*conflictIt].name << parentTile.z << parentTile.depth;
                         auto splitTile = parentTile;
                         while (splitTile.depth > (*tileIt).first.depth) {
                             for (auto subtile : splitTile.quadSplit()) {
                                 if (subtile.intersects((*tileIt).first)) {
                                     splitTile = subtile;
                                 } else if (subtile.intersects(lines[*conflictIt].bbox)) {
                                     insertToBucket(subtile, *conflictIt);
                                 }
                             }
                         }
                         if (splitTile.intersects(lines[*conflictIt].bbox)) {
                             insertToBucket(splitTile, *conflictIt);
                         }
                         (*parentTileIt).second.erase(conflictIt);
                         return true;
                     }
                 }
                 parentTile = parentTile.parent();
             }
         }
     }
     return false;
 }
 
 static QByteArray modeToString(LineInfo::Mode mode)
 {
     switch (mode) {
         case LineInfo::Tram:
             return "LineMetaDataContent::Tramway";
         case LineInfo::Subway:
             return "LineMetaDataContent::Subway";
         case LineInfo::RapidTransit:
             return "LineMetaDataContent::RapidTransit";
         default:
             assert(false);
     }
 
     return {};
 }
 
 void Generator::writeCode()
 {
     // write header
     out->write(R"(/*
     SPDX-License-Identifier: ODbL-1.0
 
     Generated code based on data from OpenStreetMap (ODbL) and Wikidata (CC0), do not edit!
 */
 
 #include "linemetadata_p.h"
 
 namespace KPublicTransport {
 
 )");
 
     // create and write string tables
     // name and logo are separated to achieve smaller index values (and thus need less bits for storage)
     // this can be done as due to file extensions on the logos we will never be able to apply suffix compression here
     StringTable nameStrTab;
     StringTable logoStrTab;
     for (const auto &line : lines) {
         nameStrTab.addString(line.name);
         logoStrTab.addString(line.lineLogos.value(0));
         logoStrTab.addString(line.productLogos.value(0));
     }
     nameStrTab.writeCode("line_name_stringtab", out);
     logoStrTab.writeCode("line_logo_stringtab", out);
     // create a symbolic name for the common no logo case (reduces diff on changes)
     out->write("static const constexpr auto NoLogo = ");
     out->write(QByteArray::number((int)logoStrTab.stringOffset(QString())));
     out->write(";\n\n");
 
     // write line table
     out->write("static const constexpr LineMetaDataContent line_data[] = {\n");
     for (const auto &line : lines) {
         out->write("    { ");
         out->write(QByteArray::number((int)nameStrTab.stringOffset(line.name)));
         out->write(", ");
         if (!line.lineLogos.isEmpty()) {
             out->write(QByteArray::number((int)logoStrTab.stringOffset(line.lineLogos.at(0))));
         } else {
             out->write("NoLogo");
         }
         out->write(", ");
         if (!line.productLogos.isEmpty()) {
             out->write(QByteArray::number((int)logoStrTab.stringOffset(line.productLogos.at(0))));
         } else {
             out->write("NoLogo");
         }
         out->write(", ");
         out->write(modeToString(line.mode));
         out->write(", Color{");
         if (line.color.isValid()) {
             out->write("0x");
             const auto col = QByteArray::number(line.color.rgb() & 0xffffff, 16);
             out->write(QByteArray(6 - col.size(), '0'));
             out->write(col);
         }
         out->write("} }, // ");
         out->write(line.name.toUtf8()),
         out->write(" OSM: ");
         out->write(QByteArray::number((long long)line.relId));
         if (line.wdId.isValid()) {
             out->write(" WD: ");
             out->write(line.wdId.toString().toUtf8());
         }
         out->write(" ");
         out->write(QByteArray::number(line.bbox.min.latF(), 'g', 4));
         out->write(", ");
         out->write(QByteArray::number(line.bbox.min.lonF(), 'g', 4));
         out->write(" x ");
         out->write(QByteArray::number(line.bbox.max.latF(), 'g', 4));
         out->write(", ");
         out->write(QByteArray::number(line.bbox.max.lonF(), 'g', 4));
         out->write("\n");
     }
     out->write(R"(};
 
 static constexpr const auto line_data_count = sizeof(line_data) / sizeof(LineMetaDataContent);
 
 static inline constexpr uint16_t Bucket(uint16_t index) { return line_data_count + index; }
 
 )");
 
     // write bucket table
     IndexedDataTable<std::vector<std::size_t>> bucketTable;
     for (const auto &zi : zQuadTree) {
         if (zi.second.size() > 1) {
             bucketTable.addEntry(zi.second);
         }
     }
     bucketTable.writeCode("int16_t", "line_data_bucketTable", out, [](const std::vector<std::size_t> &bucket, QIODevice *out) {
         for (const auto i : bucket) {
             out->write(QByteArray::number((int)i));
             out->write(", ");
         }
         out->write("-1,");
     });
 
     // write quad tree depth offsets
     out->write("static const constexpr LineMetaDataQuadTreeDepthIndex line_data_depthOffsets[] = {\n");
     int offset = -1;
     uint8_t lastDepth = 0;
     for (const auto &zi : zQuadTree) {
         ++offset;
         if (lastDepth == zi.first.depth) {
             continue;
         }
         lastDepth = zi.first.depth;
         out->write("    { ");
         out->write(QByteArray::number(lastDepth));
         out->write(", ");
         out->write(QByteArray::number((qulonglong)offset));
         out->write(" },\n");
     }
     out->write("};\n\n");
 
     // write quad tree
     out->write("static const constexpr LineMetaDataZIndex line_data_zquadtree[] = {\n");
     for (const auto &zi : zQuadTree) {
         out->write("    { ");
         out->write(QByteArray::number((qulonglong)zi.first.z));
         out->write(", ");
         if (zi.second.size() == 1) {
             out->write(QByteArray::number((qulonglong)zi.second[0]));
         } else {
             out->write("Bucket(");
             out->write(QByteArray::number((qulonglong)bucketTable.entryOffset(zi.second)));
             out->write(")");
         }
         out->write(" }, // ");
         out->write(QByteArray::number(zi.first.boundingBox().min.latF(), 'g', 4));
         out->write(", ");
         out->write(QByteArray::number(zi.first.boundingBox().min.lonF(), 'g', 4));
         out->write(" x ");
         out->write(QByteArray::number(zi.first.boundingBox().max.latF(), 'g', 4));
         out->write(", ");
         out->write(QByteArray::number(zi.first.boundingBox().max.lonF(), 'g', 4));
         out->write("\n");
     }
     out->write("};\n}\n");
 
     QCoreApplication::quit();
 }
 
 int main(int argc, char **argv)
 {
     QCoreApplication app(argc, argv);
     QCommandLineParser parser;
     parser.addHelpOption();
     QCommandLineOption outFileOption({ QStringLiteral("o") }, QStringLiteral("Output file name"), QStringLiteral("out"));
     parser.addOption(outFileOption);
     QCommandLineOption osmInputOption({ QStringLiteral("i") }, QStringLiteral("OSM input file"),  QStringLiteral("osm-in"));
     parser.addOption(osmInputOption);
     parser.process(app);
 
     QFile out(parser.value(outFileOption));
     if (!out.open(QFile::WriteOnly)) {
         qCritical() << "Failed to open output file:" << out.errorString();
         return 1;
     }
 
     QFile f(parser.value(osmInputOption));
     if (!f.open(QFile::ReadOnly)) {
         qCritical() << "Failed to open OSM input file!" << f.errorString() << f.fileName();
         QCoreApplication::exit(1);
     }
     OSM::DataSet dataSet;
     OSM::XmlParser p(&dataSet);
     p.parse(&f);
 
     Generator generator;
     generator.out = &out;
     generator.processOSMData(std::move(dataSet));
 
     return QCoreApplication::exec();
 }