#include <mbgl/tile/geometry_tile_data.hpp>
#include <mbgl/tile/tile_source.hpp>
#include <mbgl/tile/geometry_tile.hpp>
#include <mbgl/style/layer_impl.hpp>
#include <mbgl/util/worker.hpp>
#include <mbgl/util/work_request.hpp>
#include <mbgl/style/style.hpp>
#include <mbgl/storage/file_source.hpp>
#include <mbgl/geometry/feature_index.hpp>
#include <mbgl/text/collision_tile.hpp>
#include <mbgl/map/transform_state.hpp>

namespace mbgl {

GeometryTileData::GeometryTileData(const OverscaledTileID& id_,
                                   std::unique_ptr<GeometryTileSource> tileSource_,
                                   std::string sourceID,
                                   style::Style& style_,
                                   const MapMode mode_,
                                   const std::function<void(std::exception_ptr)>& callback)
    : TileData(id_, std::move(tileSource_)),
      style(style_),
      worker(style_.workers),
      tileWorker(id_,
                 sourceID,
                 *style_.spriteStore,
                 *style_.glyphAtlas,
                 *style_.glyphStore,
                 obsolete,
                 mode_) {
    auto geometryTileSource = reinterpret_cast<GeometryTileSource*>(tileSource.get());
    tileRequest = geometryTileSource->monitorTile([callback, this](std::exception_ptr err,
                                                        std::unique_ptr<GeometryTile> tile,
                                                        optional<Timestamp> modified_,
                                                        optional<Timestamp> expires_) {
        if (err) {
            callback(err);
            return;
        }

        modified = modified_;
        expires = expires_;

        if (!tile) {
            // This is a 404 response. We're treating these as empty tiles.
            workRequest.reset();
            availableData = DataAvailability::All;
            buckets.clear();
            callback(err);
            return;
        }

        // Mark the tile as pending again if it was complete before to prevent signaling a complete
        // state despite pending parse operations.
        if (availableData == DataAvailability::All) {
            availableData = DataAvailability::Some;
        }

        // Kick off a fresh parse of this tile. This happens when the tile is new, or
        // when tile data changed. Replacing the workdRequest will cancel a pending work
        // request in case there is one.
        workRequest.reset();
        workRequest = worker.parseGeometryTile(tileWorker, style.getLayers(), std::move(tile), targetConfig, [callback, this, config = targetConfig] (TileParseResult result) {
            workRequest.reset();

            std::exception_ptr error;
            if (result.is<TileParseResultData>()) {
                auto& resultBuckets = result.get<TileParseResultData>();
                availableData =
                    resultBuckets.complete ? DataAvailability::All : DataAvailability::Some;

                // Persist the configuration we just placed so that we can later check whether we need to
                // place again in case the configuration has changed.
                placedConfig = config;

                // Move over all buckets we received in this parse request, potentially overwriting
                // existing buckets in case we got a refresh parse.
                buckets = std::move(resultBuckets.buckets);

                if (isComplete()) {
                    featureIndex = std::move(resultBuckets.featureIndex);
                    geometryTile = std::move(resultBuckets.geometryTile);
                }

            } else {
                // This is triggered when parsing fails (e.g. due to an invalid vector tile)
                error = result.get<std::exception_ptr>();
                availableData = DataAvailability::All;
            }

            callback(error);
        });
    });
}

GeometryTileData::~GeometryTileData() {
    cancel();
}

bool GeometryTileData::parsePending(std::function<void(std::exception_ptr)> callback) {
    if (workRequest) {
        // There's already parsing or placement going on.
        return false;
    }

    workRequest.reset();
    workRequest = worker.parsePendingGeometryTileLayers(tileWorker, targetConfig, [this, callback, config = targetConfig] (TileParseResult result) {
        workRequest.reset();

        std::exception_ptr error;
        if (result.is<TileParseResultData>()) {
            auto& resultBuckets = result.get<TileParseResultData>();
            availableData =
                    resultBuckets.complete ? DataAvailability::All : DataAvailability::Some;

            // Move over all buckets we received in this parse request, potentially overwriting
            // existing buckets in case we got a refresh parse.
            for (auto& bucket : resultBuckets.buckets) {
                buckets[bucket.first] = std::move(bucket.second);
            }

            // Persist the configuration we just placed so that we can later check whether we need to
            // place again in case the configuration has changed.
            placedConfig = config;

            if (isComplete()) {
                featureIndex = std::move(resultBuckets.featureIndex);
                geometryTile = std::move(resultBuckets.geometryTile);
            }

        } else {
            error = result.get<std::exception_ptr>();
            availableData = DataAvailability::All;
        }

        callback(error);
    });

    return true;
}

Bucket* GeometryTileData::getBucket(const style::Layer& layer) {
    const auto it = buckets.find(layer.baseImpl->bucketName());
    if (it == buckets.end()) {
        return nullptr;
    }

    assert(it->second);
    return it->second.get();
}

void GeometryTileData::redoPlacement(const PlacementConfig newConfig, const std::function<void()>& callback) {
    if (newConfig != placedConfig) {
        targetConfig = newConfig;

        redoPlacement(callback);
    }
}

void GeometryTileData::redoPlacement(const std::function<void()>& callback) {
    // Don't start a new placement request when the current one hasn't completed yet, or when
    // we are parsing buckets.
    if (workRequest) return;

    workRequest = worker.redoPlacement(tileWorker, buckets, targetConfig, [this, callback, config = targetConfig](std::unique_ptr<CollisionTile> collisionTile) {
        workRequest.reset();

        // Persist the configuration we just placed so that we can later check whether we need to
        // place again in case the configuration has changed.
        placedConfig = config;

        for (auto& bucket : buckets) {
            bucket.second->swapRenderData();
        }

        if (featureIndex) {
            featureIndex->setCollisionTile(std::move(collisionTile));
        }

        // The target configuration could have changed since we started placement. In this case,
        // we're starting another placement run.
        if (placedConfig != targetConfig) {
            redoPlacement(callback);
        } else {
            callback();
        }
    });
}

void GeometryTileData::queryRenderedFeatures(
    std::unordered_map<std::string, std::vector<Feature>>& result,
    const GeometryCoordinates& queryGeometry,
    const TransformState& transformState,
    const optional<std::vector<std::string>>& layerIDs) {

    if (!featureIndex || !geometryTile) return;

    featureIndex->query(result,
                        { queryGeometry },
                        transformState.getAngle(),
                        util::tileSize * id.overscaleFactor(),
                        std::pow(2, transformState.getZoom() - id.overscaledZ),
                        layerIDs,
                        *geometryTile,
                        id.canonical,
                        style);
}

void GeometryTileData::cancel() {
    obsolete = true;
    tileRequest.reset();
    workRequest.reset();
}

} // namespace mbgl