package com.ruoyi.system.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.ruoyi.system.model.TAppUserVisit;
import com.ruoyi.system.model.TBigGiftPackageOrder;
import com.ruoyi.system.model.TPhysicalGoodsOrder;
import com.ruoyi.system.query.DashboardStatisticsQuery;
import com.ruoyi.system.service.DashboardStatisticsService;
import com.ruoyi.system.service.TAppUserVisitService;
import com.ruoyi.system.service.TBigGiftPackageOrderService;
import com.ruoyi.system.service.TPhysicalGoodsOrderService;
import com.ruoyi.system.vo.*;
import lombok.RequiredArgsConstructor;
import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Service;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.temporal.ChronoUnit;
import java.util.*;
import java.util.stream.Collectors;

/**
 * 数据统计面板 服务实现类
 *
 * @author xiaochen
 * @since 2025-12-23
 */
@Service
@RequiredArgsConstructor(onConstructor_ = @Lazy)
public class DashboardStatisticsServiceImpl implements DashboardStatisticsService {

    private final TAppUserVisitService appUserVisitService;
    private final TPhysicalGoodsOrderService physicalGoodsOrderService;
    private final TBigGiftPackageOrderService bigGiftPackageOrderService;

    /**
     * 实物商品订单有效状态：完成支付(2)、确认收货(3)
     */
    private static final List<Integer> PHYSICAL_ORDER_VALID_STATUS = Arrays.asList(2, 3);

    /**
     * 大礼包订单有效状态：已付订金(2)、完成支付(3)、确认收货(4)
     */
    private static final List<Integer> BIG_GIFT_ORDER_VALID_STATUS = Arrays.asList(2, 3, 4);

    @Override
    public DashboardStatisticsVO getStatistics(DashboardStatisticsQuery query) {
        // 处理日期范围，默认为当月
        LocalDate endDate = query.getEndDate() != null ? query.getEndDate() : LocalDate.now();
        LocalDate startDate = query.getStartDate() != null ? query.getStartDate() : endDate.withDayOfMonth(1);

        // 计算上一周期的日期范围（用于环比计算）
        long daysBetween = ChronoUnit.DAYS.between(startDate, endDate) + 1;
        LocalDate lastPeriodEnd = startDate.minusDays(1);
        LocalDate lastPeriodStart = lastPeriodEnd.minusDays(daysBetween - 1);

        return DashboardStatisticsVO.builder()
                .visitStats(buildVisitStats(startDate, endDate, lastPeriodStart, lastPeriodEnd))
                .orderCountStats(buildOrderCountStats(startDate, endDate, lastPeriodStart, lastPeriodEnd))
                .orderAmountStats(buildOrderAmountStats(startDate, endDate, lastPeriodStart, lastPeriodEnd))
                .monthlyStats(buildMonthlyStats(startDate, endDate))
                .build();
    }

    /**
     * 构建客户访问量统计
     */
    private StatisticsItemVO buildVisitStats(LocalDate startDate, LocalDate endDate,
                                              LocalDate lastPeriodStart, LocalDate lastPeriodEnd) {
        // 当前周期访问量
        long currentTotal = appUserVisitService.count(new LambdaQueryWrapper<TAppUserVisit>()
                .between(TAppUserVisit::getVisitDate, startDate, endDate));

        // 上一周期访问量
        long lastTotal = appUserVisitService.count(new LambdaQueryWrapper<TAppUserVisit>()
                .between(TAppUserVisit::getVisitDate, lastPeriodStart, lastPeriodEnd));

        // 趋势数据（按日统计）
        List<TAppUserVisit> visitList = appUserVisitService.list(new LambdaQueryWrapper<TAppUserVisit>()
                .between(TAppUserVisit::getVisitDate, startDate, endDate));

        Map<LocalDate, Long> visitByDate = visitList.stream()
                .collect(Collectors.groupingBy(TAppUserVisit::getVisitDate, Collectors.counting()));

        List<TrendDataVO> trend = buildDailyTrend(startDate, endDate, visitByDate);

        return StatisticsItemVO.builder()
                .total(BigDecimal.valueOf(currentTotal))
                .rate(calculateRate(currentTotal, lastTotal))
                .trend(trend)
                .build();
    }

    /**
     * 构建订单数统计
     */
    private StatisticsItemVO buildOrderCountStats(LocalDate startDate, LocalDate endDate,
                                                   LocalDate lastPeriodStart, LocalDate lastPeriodEnd) {
        LocalDateTime startDateTime = startDate.atStartOfDay();
        LocalDateTime endDateTime = endDate.atTime(LocalTime.MAX);
        LocalDateTime lastStartDateTime = lastPeriodStart.atStartOfDay();
        LocalDateTime lastEndDateTime = lastPeriodEnd.atTime(LocalTime.MAX);

        // 当前周期订单数
        long physicalCount = physicalGoodsOrderService.count(new LambdaQueryWrapper<TPhysicalGoodsOrder>()
                .in(TPhysicalGoodsOrder::getStatus, PHYSICAL_ORDER_VALID_STATUS)
                .between(TPhysicalGoodsOrder::getCreateTime, startDateTime, endDateTime));

        long bigGiftCount = bigGiftPackageOrderService.count(new LambdaQueryWrapper<TBigGiftPackageOrder>()
                .in(TBigGiftPackageOrder::getStatus, BIG_GIFT_ORDER_VALID_STATUS)
                .between(TBigGiftPackageOrder::getCreateTime, startDateTime, endDateTime));

        long currentTotal = physicalCount + bigGiftCount;

        // 上一周期订单数
        long lastPhysicalCount = physicalGoodsOrderService.count(new LambdaQueryWrapper<TPhysicalGoodsOrder>()
                .in(TPhysicalGoodsOrder::getStatus, PHYSICAL_ORDER_VALID_STATUS)
                .between(TPhysicalGoodsOrder::getCreateTime, lastStartDateTime, lastEndDateTime));

        long lastBigGiftCount = bigGiftPackageOrderService.count(new LambdaQueryWrapper<TBigGiftPackageOrder>()
                .in(TBigGiftPackageOrder::getStatus, BIG_GIFT_ORDER_VALID_STATUS)
                .between(TBigGiftPackageOrder::getCreateTime, lastStartDateTime, lastEndDateTime));

        long lastTotal = lastPhysicalCount + lastBigGiftCount;

        // 趋势数据
        List<TrendDataVO> trend = buildOrderCountTrend(startDate, endDate);

        return StatisticsItemVO.builder()
                .total(BigDecimal.valueOf(currentTotal))
                .rate(calculateRate(currentTotal, lastTotal))
                .trend(trend)
                .build();
    }

    /**
     * 构建订单金额统计
     */
    private StatisticsItemVO buildOrderAmountStats(LocalDate startDate, LocalDate endDate,
                                                    LocalDate lastPeriodStart, LocalDate lastPeriodEnd) {
        LocalDateTime startDateTime = startDate.atStartOfDay();
        LocalDateTime endDateTime = endDate.atTime(LocalTime.MAX);
        LocalDateTime lastStartDateTime = lastPeriodStart.atStartOfDay();
        LocalDateTime lastEndDateTime = lastPeriodEnd.atTime(LocalTime.MAX);

        // 当前周期订单金额
        BigDecimal currentTotal = calculateTotalOrderAmount(startDateTime, endDateTime);

        // 上一周期订单金额
        BigDecimal lastTotal = calculateTotalOrderAmount(lastStartDateTime, lastEndDateTime);

        // 趋势数据
        List<TrendDataVO> trend = buildOrderAmountTrend(startDate, endDate);

        return StatisticsItemVO.builder()
                .total(currentTotal)
                .rate(calculateRate(currentTotal, lastTotal))
                .trend(trend)
                .build();
    }

    /**
     * 计算指定时间范围内的订单总金额
     */
    private BigDecimal calculateTotalOrderAmount(LocalDateTime startDateTime, LocalDateTime endDateTime) {
        // 实物商品订单金额
        List<TPhysicalGoodsOrder> physicalOrders = physicalGoodsOrderService.list(
                new LambdaQueryWrapper<TPhysicalGoodsOrder>()
                        .in(TPhysicalGoodsOrder::getStatus, PHYSICAL_ORDER_VALID_STATUS)
                        .between(TPhysicalGoodsOrder::getCreateTime, startDateTime, endDateTime)
                        .select(TPhysicalGoodsOrder::getPaymentPrice));

        BigDecimal physicalAmount = physicalOrders.stream()
                .map(o -> o.getPaymentPrice() != null ? o.getPaymentPrice() : BigDecimal.ZERO)
                .reduce(BigDecimal.ZERO, BigDecimal::add);

        // 大礼包订单金额
        List<TBigGiftPackageOrder> bigGiftOrders = bigGiftPackageOrderService.list(
                new LambdaQueryWrapper<TBigGiftPackageOrder>()
                        .in(TBigGiftPackageOrder::getStatus, BIG_GIFT_ORDER_VALID_STATUS)
                        .between(TBigGiftPackageOrder::getCreateTime, startDateTime, endDateTime)
                        .select(TBigGiftPackageOrder::getPaymentPrice));

        BigDecimal bigGiftAmount = bigGiftOrders.stream()
                .map(o -> o.getPaymentPrice() != null ? o.getPaymentPrice() : BigDecimal.ZERO)
                .reduce(BigDecimal.ZERO, BigDecimal::add);

        return physicalAmount.add(bigGiftAmount);
    }

    /**
     * 构建月度订单统计
     */
    private List<MonthlyOrderStatisticsVO> buildMonthlyStats(LocalDate startDate, LocalDate endDate) {
        LocalDateTime startDateTime = startDate.atStartOfDay();
        LocalDateTime endDateTime = endDate.atTime(LocalTime.MAX);

        // 获取实物商品订单
        List<TPhysicalGoodsOrder> physicalOrders = physicalGoodsOrderService.list(
                new LambdaQueryWrapper<TPhysicalGoodsOrder>()
                        .in(TPhysicalGoodsOrder::getStatus, PHYSICAL_ORDER_VALID_STATUS)
                        .between(TPhysicalGoodsOrder::getCreateTime, startDateTime, endDateTime));

        // 获取大礼包订单
        List<TBigGiftPackageOrder> bigGiftOrders = bigGiftPackageOrderService.list(
                new LambdaQueryWrapper<TBigGiftPackageOrder>()
                        .in(TBigGiftPackageOrder::getStatus, BIG_GIFT_ORDER_VALID_STATUS)
                        .between(TBigGiftPackageOrder::getCreateTime, startDateTime, endDateTime));

        // 按月份分组统计
        Map<String, Long> countByMonth = new TreeMap<>();
        Map<String, BigDecimal> amountByMonth = new TreeMap<>();

        // 统计实物商品订单
        for (TPhysicalGoodsOrder order : physicalOrders) {
            String month = order.getCreateTime().getMonthValue() + "月";
            countByMonth.merge(month, 1L, Long::sum);
            BigDecimal amount = order.getPaymentPrice() != null ? order.getPaymentPrice() : BigDecimal.ZERO;
            amountByMonth.merge(month, amount, BigDecimal::add);
        }

        // 统计大礼包订单
        for (TBigGiftPackageOrder order : bigGiftOrders) {
            String month = order.getCreateTime().getMonthValue() + "月";
            countByMonth.merge(month, 1L, Long::sum);
            BigDecimal amount = order.getPaymentPrice() != null ? order.getPaymentPrice() : BigDecimal.ZERO;
            amountByMonth.merge(month, amount, BigDecimal::add);
        }

        // 构建返回结果
        List<MonthlyOrderStatisticsVO> result = new ArrayList<>();
        for (String month : countByMonth.keySet()) {
            result.add(new MonthlyOrderStatisticsVO(
                    month,
                    countByMonth.getOrDefault(month, 0L),
                    amountByMonth.getOrDefault(month, BigDecimal.ZERO)
            ));
        }

        // 按月份数字排序
        result.sort(Comparator.comparingInt(vo -> Integer.parseInt(vo.getMonth().replace("月", ""))));

        return result;
    }

    /**
     * 构建每日趋势数据
     */
    private List<TrendDataVO> buildDailyTrend(LocalDate startDate, LocalDate endDate,
                                               Map<LocalDate, Long> dataByDate) {
        List<TrendDataVO> trend = new ArrayList<>();
        LocalDate current = startDate;
        while (!current.isAfter(endDate)) {
            Long value = dataByDate.getOrDefault(current, 0L);
            trend.add(new TrendDataVO(current.toString(), value));
            current = current.plusDays(1);
        }
        return trend;
    }

    /**
     * 构建订单数趋势数据（优化：一次查询，内存分组）
     */
    private List<TrendDataVO> buildOrderCountTrend(LocalDate startDate, LocalDate endDate) {
        LocalDateTime startDateTime = startDate.atStartOfDay();
        LocalDateTime endDateTime = endDate.atTime(LocalTime.MAX);

        // 一次性查询所有实物商品订单
        List<TPhysicalGoodsOrder> physicalOrders = physicalGoodsOrderService.list(
                new LambdaQueryWrapper<TPhysicalGoodsOrder>()
                        .in(TPhysicalGoodsOrder::getStatus, PHYSICAL_ORDER_VALID_STATUS)
                        .between(TPhysicalGoodsOrder::getCreateTime, startDateTime, endDateTime)
                        .select(TPhysicalGoodsOrder::getCreateTime));

        // 一次性查询所有大礼包订单
        List<TBigGiftPackageOrder> bigGiftOrders = bigGiftPackageOrderService.list(
                new LambdaQueryWrapper<TBigGiftPackageOrder>()
                        .in(TBigGiftPackageOrder::getStatus, BIG_GIFT_ORDER_VALID_STATUS)
                        .between(TBigGiftPackageOrder::getCreateTime, startDateTime, endDateTime)
                        .select(TBigGiftPackageOrder::getCreateTime));

        // 按日期分组统计
        Map<LocalDate, Long> countByDate = new HashMap<>();
        physicalOrders.forEach(o -> {
            LocalDate date = o.getCreateTime().toLocalDate();
            countByDate.merge(date, 1L, Long::sum);
        });
        bigGiftOrders.forEach(o -> {
            LocalDate date = o.getCreateTime().toLocalDate();
            countByDate.merge(date, 1L, Long::sum);
        });

        // 构建趋势数据
        return buildDailyTrend(startDate, endDate, countByDate);
    }

    /**
     * 构建订单金额趋势数据（优化：一次查询，内存分组）
     */
    private List<TrendDataVO> buildOrderAmountTrend(LocalDate startDate, LocalDate endDate) {
        LocalDateTime startDateTime = startDate.atStartOfDay();
        LocalDateTime endDateTime = endDate.atTime(LocalTime.MAX);

        // 一次性查询所有实物商品订单
        List<TPhysicalGoodsOrder> physicalOrders = physicalGoodsOrderService.list(
                new LambdaQueryWrapper<TPhysicalGoodsOrder>()
                        .in(TPhysicalGoodsOrder::getStatus, PHYSICAL_ORDER_VALID_STATUS)
                        .between(TPhysicalGoodsOrder::getCreateTime, startDateTime, endDateTime)
                        .select(TPhysicalGoodsOrder::getCreateTime, TPhysicalGoodsOrder::getPaymentPrice));

        // 一次性查询所有大礼包订单
        List<TBigGiftPackageOrder> bigGiftOrders = bigGiftPackageOrderService.list(
                new LambdaQueryWrapper<TBigGiftPackageOrder>()
                        .in(TBigGiftPackageOrder::getStatus, BIG_GIFT_ORDER_VALID_STATUS)
                        .between(TBigGiftPackageOrder::getCreateTime, startDateTime, endDateTime)
                        .select(TBigGiftPackageOrder::getCreateTime, TBigGiftPackageOrder::getPaymentPrice));

        // 按日期分组统计金额
        Map<LocalDate, BigDecimal> amountByDate = new HashMap<>();
        physicalOrders.forEach(o -> {
            LocalDate date = o.getCreateTime().toLocalDate();
            BigDecimal amount = o.getPaymentPrice() != null ? o.getPaymentPrice() : BigDecimal.ZERO;
            amountByDate.merge(date, amount, BigDecimal::add);
        });
        bigGiftOrders.forEach(o -> {
            LocalDate date = o.getCreateTime().toLocalDate();
            BigDecimal amount = o.getPaymentPrice() != null ? o.getPaymentPrice() : BigDecimal.ZERO;
            amountByDate.merge(date, amount, BigDecimal::add);
        });

        // 构建趋势数据
        List<TrendDataVO> trend = new ArrayList<>();
        LocalDate current = startDate;
        while (!current.isAfter(endDate)) {
            BigDecimal value = amountByDate.getOrDefault(current, BigDecimal.ZERO);
            trend.add(new TrendDataVO(current.toString(), value));
            current = current.plusDays(1);
        }
        return trend;
    }

    /**
     * 计算环比增长率
     *
     * @param current 当前值
     * @param last    上期值
     * @return 环比增长率（百分比）
     */
    private BigDecimal calculateRate(long current, long last) {
        if (last == 0) {
            return current > 0 ? BigDecimal.valueOf(100) : BigDecimal.ZERO;
        }
        return BigDecimal.valueOf(current - last)
                .multiply(BigDecimal.valueOf(100))
                .divide(BigDecimal.valueOf(last), 2, RoundingMode.HALF_UP);
    }

    /**
     * 计算环比增长率（BigDecimal版本）
     */
    private BigDecimal calculateRate(BigDecimal current, BigDecimal last) {
        if (last.compareTo(BigDecimal.ZERO) == 0) {
            return current.compareTo(BigDecimal.ZERO) > 0 ? BigDecimal.valueOf(100) : BigDecimal.ZERO;
        }
        return current.subtract(last)
                .multiply(BigDecimal.valueOf(100))
                .divide(last, 2, RoundingMode.HALF_UP);
    }

}