package com.izouma.walkchina.service;

import com.github.kevinsawicki.http.HttpRequest;
import com.google.gson.Gson;
import com.izouma.walkchina.constant.AppConstants;
import com.izouma.walkchina.domain.City;
import com.izouma.walkchina.domain.JourneyStage;
import com.izouma.walkchina.domain.UserInfo;
import com.izouma.walkchina.domain.UserJourney;
import com.izouma.walkchina.dto.Location;
import com.izouma.walkchina.dto.MapRegion;
import com.izouma.walkchina.dto.UserMap;
import com.izouma.walkchina.dto.UserMarker;
import com.izouma.walkchina.dto.webservice.DirectionResponse;
import com.izouma.walkchina.dto.webservice.RouteStep;
import com.izouma.walkchina.exception.ServiceException;
import com.izouma.walkchina.repo.*;
import com.izouma.walkchina.utils.SecurityUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.data.jpa.domain.Specification;
import org.springframework.stereotype.Service;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.time.LocalDate;
import java.util.*;

import static java.time.temporal.ChronoUnit.DAYS;

@Service
@Slf4j
public class MapService {
    @Autowired
    private CityRepository         cityRepository;
    @Autowired
    private UserJourneyRepository  userJourneyRepository;
    @Autowired
    private JourneyStageRepository journeyStageRepository;
    @Autowired
    private UserInfoRepository     userInfoRepository;
    @Autowired
    private StageAwardRepository   stageAwardRepository;
    @Autowired
    private WalkDataRepository     walkDataRepository;
    @Value("${aliyun.oss_domain}")
    private String                 ossDomain;

    public List<City> citiesInRegion(MapRegion mapRegion) {
        Specification<City> specification = (Specification<City>) (root, criteriaQuery, criteriaBuilder) -> {
            return criteriaBuilder.and(criteriaBuilder.between(root.get("longitude"),
                                                               mapRegion.getSouthwest().getLongitude(),
                                                               mapRegion.getNortheast().getLongitude()),
                                       criteriaBuilder.between(root.get("latitude"),
                                                               mapRegion.getSouthwest().getLatitude(),
                                                               mapRegion.getNortheast().getLatitude()));
        };
        return cityRepository.findAll(specification);
    }

    public List<City> findNearCities(Long id, Long userId) {
        return cityRepository.findNear(id, userId);
    }

    public Collection<UserMarker> usersInRegion(Long userId, MapRegion mapRegion) {
        List<UserMarker> list = userInfoRepository.findInRegion(userId, mapRegion.getSouthwest().getLatitude(), mapRegion.getSouthwest().getLongitude(),
                                                                mapRegion.getNortheast().getLongitude(), mapRegion.getNortheast().getLongitude());
        for (UserMarker userMarker : list) {
            userMarker.setCanSteal(stageAwardRepository.countAllByUserIdAndReceivedEquals(userMarker.getUserId(), false) > 1);
            userMarker.setIcon(ossDomain + "/marker/user/" + userMarker.getUserId() + ".png");
        }
        return list;
    }

    public DirectionResponse direction(Location from, Location to) {
        Map<String, Object> params = new HashMap<>();
        params.put("from", from.getLatitude() + "," + from.getLongitude());
        params.put("to", to.getLatitude() + "," + to.getLongitude());
        params.put("key", "YO4BZ-G75L5-CWJIV-QDPOY-77OIH-LGFMT");
        String body = HttpRequest.get("https://apis.map.qq.com/ws/direction/v1/walking/", params, false).body();
        Gson gson = new Gson();
        return gson.fromJson(body, DirectionResponse.class);
    }

    public UserMap userMap(Long userId) {
        UserJourney userJourney = Optional.ofNullable(userJourneyRepository.findByUserId(userId)).orElseThrow(new ServiceException("无记录"));
        City origin = Optional.ofNullable(userJourney.getOrigin()).orElseThrow(new ServiceException("无记录"));
        City destination = Optional.ofNullable(userJourney.getDestination()).orElseThrow(new ServiceException("无记录"));
        UserInfo userInfo = userInfoRepository.findById(userId).orElseThrow(new ServiceException("用户不存在"));
        UserMap userMap = UserMap.builder()
                                 .polyline(minifyPolyline(userJourney.getPolyline()))
                                 .origin(origin)
                                 .destination(destination)
                                 .build();
        List<Double> progressPolyline = new ArrayList<>();
        List<JourneyStage> stages = journeyStageRepository.findAllByJourneyIdOrderById(userJourney.getId());
        for (int i = 0; i < stages.size() - 1; i++) {
            progressPolyline.addAll(stages.get(i).getPolyline());
        }
        JourneyStage latestStage = stages.get(stages.size() - 1);
        userMap.setDestination(latestStage.getDestination());
        userMap.setNearOrigin(latestStage.getOrigin());
        userMap.setProgress(latestStage.getProgress());
        userMap.setCurrentSteps(latestStage.getCurrentSteps());
        userMap.setStageAwards(stageAwardRepository.findAllByUserIdAndStageId(userId, latestStage.getId()));
        userMap.setDays((int) DAYS.between(latestStage.getCreatedAt().toLocalDate(), LocalDate.now()) + 1);

        List<RouteStep> steps = latestStage.getRouteSteps();
        // int distance = 0;
        // for (RouteStep step : steps) {
        //     distance += step.getDistance();
        //     if (distance < latestStage.getDistance() * latestStage.getProgress()) {
        //         for (int j = step.getPolylineIdx().get(0); j <= step.getPolylineIdx().get(1); j++) {
        //             progressPolyline.add(latestStage.getPolyline().get(j));
        //         }
        //     } else {
        //         double p = 1 - (distance - (latestStage.getDistance() * latestStage.getProgress())) / (double) step.getDistance();
        //         int start = step.getPolylineIdx().get(0);
        //         int end = start + (int) ((step.getPolylineIdx().get(1) - step.getPolylineIdx().get(0)) * p);
        //         end = end + (end % 2 == 0 ? 1 : 0);
        //         if (end < start + 1) {
        //             end = start + 1;
        //         }
        //         if (end > step.getPolylineIdx().get(1)) {
        //             end = step.getPolylineIdx().get(1);
        //         }
        //
        //         for (int j = start; j <= end; j++) {
        //             progressPolyline.add(latestStage.getPolyline().get(j));
        //         }
        //         break;
        //     }
        // }
        for (int i = 0; i <= endPoint(steps, latestStage.getDistance() * latestStage.getProgress()); i++) {
            progressPolyline.add(latestStage.getPolyline().get(i));
        }

        userMap.setProgressPolyline(minifyPolyline(progressPolyline));
        return userMap;
    }

    int endPoint(List<RouteStep> steps, double distance) {
        int d = 0;
        for (RouteStep step : steps) {
            d += step.getDistance();
            if (d >= distance) {
                double p = 1 - (d - distance) / step.getDistance();
                int start = step.getPolylineIdx().get(0);
                int end = start + (int) ((step.getPolylineIdx().get(1) - step.getPolylineIdx().get(0)) * p);
                end = end + (end % 2 == 0 ? 1 : 0);
                if (end < start + 1) {
                    end = start + 1;
                }
                if (end > step.getPolylineIdx().get(1)) {
                    end = step.getPolylineIdx().get(1);
                }
                return end;
            }
        }
        return steps.get(steps.size() - 1).getPolylineIdx().get(1);
    }


    List<Double> extractPolyline(List<Double> polyline) {
        List<Double> list = new ArrayList<>(polyline);
        for (int i = 2; i < list.size(); i++) {
            list.set(i, BigDecimal.valueOf(list.get(i - 2) + list.get(i) / 1000000).setScale(6, RoundingMode.HALF_EVEN).doubleValue());
        }
        return list;
    }

    List<Object> compressPolyline(List<Double> polyline) {
        List<Object> list = new ArrayList<>(polyline);
        for (int i = 2; i < list.size(); i++) {
            list.set(i, Math.round(polyline.get(i) * 1000000d - polyline.get(i - 2) * 1000000d));
        }
        return list;
    }

    private List<Object> minifyPolyline(List<Double> polyline) {
        List<Double> list = new ArrayList<>();
        List<Double> extracted = extractPolyline(polyline);
        list.add(polyline.get(0));
        list.add(polyline.get(1));
        for (int i = 2; i < polyline.size(); i += 20) {
            double d0 = Math.abs(polyline.get(i));
            double d1 = Math.abs(polyline.get(i + 1));
            if (d0 == 0 && d1 == 0) {
                continue;
            }
            if (d0 < 20 && d1 < 20) {
                continue;
            }
            list.add(extracted.get(i));
            list.add(extracted.get(i + 1));
        }
        return compressPolyline(list);
    }

    public Map<String, Object> calcAward(Long originId, Long destinationId) {
        City origin = cityRepository.findById(originId).orElseThrow(new ServiceException("无记录"));
        City destination = cityRepository.findById(destinationId).orElseThrow(new ServiceException("无记录"));
        DirectionResponse response = direction(new Location(origin.getLatitude(), origin.getLongitude()), new Location(destination.getLatitude(), destination.getLongitude()));
        if (response.getStatus() != 0) {
            throw new ServiceException(response.getMessage());
        }
        Integer distance = response.getResult().getRoutes().get(0).getDistance();
        Long step = Math.round(distance / AppConstants.STEP_TO_DISTANCE_RATE);
        UserInfo userInfo = userInfoRepository.findById(SecurityUtils.getAuthenticatedUser().getId()).orElseThrow(new ServiceException("用户不存在"));
        BigDecimal award = userInfo.getPrice();
        Map<String, Object> map = new HashMap<>();
        map.put("step", step);
        map.put("award", award);
        return map;
    }
}