package io.delphiplatform.api.v3.bigtable;

import org.springframework.stereotype.Service;

import java.time.LocalDate;
import java.time.temporal.ChronoUnit;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import javax.transaction.NotSupportedException;

import io.delphiplatform.api.util.CollectionUtils;
import io.delphiplatform.api.v3.bigtable.config.RowKeyAggPeriod;
import io.delphiplatform.api.v3.bigtable.config.RowKeyGroup;
import io.delphiplatform.api.v3.bigtable.config.RowKeyRequestType;
import io.delphiplatform.api.v3.bigtable.config.RequestRowKeyHandle;
import io.delphiplatform.api.v3.bigtable.entity.TikTokTrackMetrics;
import io.delphiplatform.api.v3.bigtable.processing.TikTokTrackMetricsAggregator;
import io.delphiplatform.api.v3.bigtable.processing.TikTokTrackMetricsConverter;
import io.delphiplatform.api.v3.constant.BigtableTableName;
import io.delphiplatform.api.v3.model.tiktok.IsrcContentTypeCountryTikTokTrackAnalyticsBreakdowns;
import io.delphiplatform.api.v3.model.tiktok.TikTokBreakdown;
import io.delphiplatform.api.v3.model.tiktok.TikTokTrackAnalytics;
import io.delphiplatform.api.v3.model.tiktok.TikTokTrackAnalyticsBreakdowns;
import io.delphiplatform.api.v3.model.video.ExpandTo;
import io.delphiplatform.api.v3.rdb.service.TrackService;
import io.delphiplatform.api.v3.view.util.Params;

@Service
public class BigtableTikTokTrackAnalyticsService {

    private final BigtableQueryExecutor queryExecutor;
    private final BigtableRowReader rowReader;
    private final TikTokTrackMetricsConverter tikTokTrackMetricsConverter;
    private final TikTokTrackMetricsAggregator metricsAggregator;
    private final TrackService trackService;


    public BigtableTikTokTrackAnalyticsService(BigtableQueryExecutor queryExecutor, BigtableRowReader rowReader,
        TikTokTrackMetricsConverter tikTokTrackMetricsConverter,
        TikTokTrackMetricsAggregator metricsAggregator, TrackService trackService) {
        this.queryExecutor = queryExecutor;
        this.rowReader = rowReader;
        this.tikTokTrackMetricsConverter = tikTokTrackMetricsConverter;
        this.metricsAggregator = metricsAggregator;
        this.trackService = trackService;
    }

    public CompletableFuture<TikTokTrackAnalytics> getAnalytics(Params params)
        throws NotSupportedException {

        return getAnalyticsEnhanced(params, false)
            .thenApply(models -> CollectionUtils.isEmpty(models) ? createTikTokTrackAnalytics(
                new IsrcContentTypeCountryTikTokTrackAnalyticsBreakdowns(), params) : models.get(0));
    }

    private TikTokTrackAnalytics createTikTokTrackAnalytics(
        IsrcContentTypeCountryTikTokTrackAnalyticsBreakdowns contentTypeCountryBreakdown, Params params) {
        TikTokTrackAnalyticsBreakdowns breakdowns = new TikTokTrackAnalyticsBreakdowns();

        if (CollectionUtils.contains(params.getTikTokBreakdowns(), TikTokBreakdown.CONTENT_TYPE_COUNTRY)) {
            breakdowns.contentTypeCountry(contentTypeCountryBreakdown);
        }
        if (CollectionUtils.contains(params.getTikTokBreakdowns(), TikTokBreakdown.DAILY)) {
            breakdowns.daily(metricsAggregator.dailyBreakdown(contentTypeCountryBreakdown, params.getMetrics()));
        }
        if (CollectionUtils.contains(params.getTikTokBreakdowns(), TikTokBreakdown.COUNTRY_TOTALS)) {
            breakdowns
                .countryTotals(metricsAggregator.countryTotalsBreakdown(contentTypeCountryBreakdown));
        }
        if (CollectionUtils.contains(params.getTikTokBreakdowns(), TikTokBreakdown.COUNTRY)) {
            breakdowns.countryDaily(metricsAggregator.countryDailyBreakdown(contentTypeCountryBreakdown));
        }
        TikTokTrackAnalytics tikTokTrackAnalytics = new TikTokTrackAnalytics();
        tikTokTrackAnalytics.breakdowns(breakdowns);
        return tikTokTrackAnalytics;
    }

    public CompletableFuture<List<TikTokTrackAnalytics>> getListAnalytics(Params params)
        throws NotSupportedException {

        return getAnalyticsEnhanced(params, true);
    }

    private CompletableFuture<List<TikTokTrackAnalytics>> getAnalyticsEnhanced(Params params, boolean setIsrc)
        throws NotSupportedException {

        Map<String, Set<String>> isrcToRelated = new HashMap<>();
        params.getIsrc().forEach(requestIsrc -> {
            if (CollectionUtils.contains(params.getExpandTo(), ExpandTo.RELATED_ISRCS)) {
                Set<String> relatedIsrc = trackService.findRelatedIsrc(Collections.singleton(requestIsrc));
                relatedIsrc.add(requestIsrc);
                isrcToRelated.put(requestIsrc, relatedIsrc);
            } else {
                isrcToRelated.put(requestIsrc, Set.of(requestIsrc));
            }
        });
        Set<String> allIsrcsToRequest = isrcToRelated.values().stream().flatMap(Collection::stream)
            .collect(Collectors.toSet());

        RowKeyGenerator rowKeyGenerator = new RowKeyGenerator(
            params.toBuilder().isrc(new ArrayList<>(allIsrcsToRequest)).build(),
            RowKeyGroup.TIKTOK, RowKeyAggPeriod.EMPTY, RowKeyRequestType.RANGE);
        List<RequestRowKeyHandle> rowKeys = rowKeyGenerator.getRequestRowKeyHandles();

        CompletableFuture<Stream<TikTokTrackMetrics>> allRows = getAllRows(rowKeys);

        return allRows
            .thenApply(metrics -> tikTokTrackMetricsConverter.convert(metrics, params.getCountryCode()))
            .thenApply(models -> {
                Collection<IsrcContentTypeCountryTikTokTrackAnalyticsBreakdowns> contentTypeCountryBreakdowns = metricsAggregator
                    .getListContentTypeCountryBreakdown(models, isrcToRelated, params.getMetrics());

                return contentTypeCountryBreakdowns.stream()
                    .map(contentTypeCountryBreakdown -> {
                        TikTokTrackAnalytics result = createTikTokTrackAnalytics(contentTypeCountryBreakdown, params);
                        LocalDate minDate = contentTypeCountryBreakdown.getMinDate();
                        LocalDate maxDate = contentTypeCountryBreakdown.getMaxDate();
                        if (setIsrc) {
                            result.setIsrc(contentTypeCountryBreakdown.getIscr());
                        }
                        result.setMinDate(minDate);
                        result.setMaxDate(maxDate);
                        if (minDate != null && maxDate != null) {
                            result.setDaysCount((int) ChronoUnit.DAYS.between(minDate, maxDate) + 1);
                        }
                        return result;
                    }).collect(Collectors.toList());
            });
    }

    private CompletableFuture<Stream<TikTokTrackMetrics>> getAllRows(List<RequestRowKeyHandle> itemKeys) {
        return queryExecutor.executePartitioned(BigtableTableName.TIKTOK, itemKeys)
            .thenApply(rowStream -> rowStream.map(row -> rowReader.readRow(TikTokTrackMetrics.class, row)));
    }

}