package services

import (
	"context"
	"fmt"
	"fwh-toolbox-server/cache"
	"fwh-toolbox-server/domain"
	"fwh-toolbox-server/repositories"
	"time"

	"go.uber.org/zap"
)

// 从数据库获取shutdown统计最新日期
func GetShutdownStatisticsDate() (*string, error) {
	return getDashboardDate()
}

// 从数据库获取shutdown统计
func GetShutdownStatistics(date *string) (*domain.ShutdownStatisticsDashboard, error) {
	currDate, err := getDashboardDate()
	if err != nil {
		return nil, err
	}

	var weekly *domain.ShutdownStatisticsArea[[7]uint]
	var yearly *domain.ShutdownStatisticsArea[[12]uint]
	if date == nil {
		date = currDate
	}

	weekly, err = getDashboardWeekly(*date)
	if err != nil {
		return nil, err
	}
	yearly, err = getDashboardYearly(*date)
	if err != nil {
		return nil, err
	}

	return &domain.ShutdownStatisticsDashboard{
		Date:   *date,
		Weekly: *weekly,
		Yearly: *yearly,
	}, nil
}

// 从数据库获取shutdown统计信息详细数据
func GetShutdownInfoMap(date *string) (*domain.ShutdownStatisticsItem, error) {
	currDate, err := getDashboardDate()
	if err != nil {
		return nil, err
	}

	if date == nil {
		date = currDate
	}

	return repositories.GetStatisticsShutdown(*date)
}

// 对Dashboard常规数据做缓存
const (
	RedisKeyDashboardDate   = "fwhtoolbox:dashboard:date"
	RedisKeyDashboardWeekly = "fwhtoolbox:dashboard:weekly"
	RedisKeyDashboardYearly = "fwhtoolbox:dashboard:yearly"
)

func getDashboardDate() (*string, error) {
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	var date string
	err := cache.GetJSON(ctx, RedisKeyDashboardDate, &date)
	if err == nil {
		return &date, nil // 命中缓存
	}

	// 未命中缓存 → 查询数据库
	shutdownData, err := repositories.GetLatestStatisticsShutdown()
	if err != nil {
		return nil, err
	}
	date = shutdownData.Date

	// 缓存结果 24h
	cache.SetJSON(ctx, RedisKeyDashboardDate, date, time.Hour*24)
	return &date, nil
}

func getDashboardWeekly(date string) (*domain.ShutdownStatisticsArea[[7]uint], error) {
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	// 未命中缓存 → 查询数据库
	currDate, err := getDashboardDate()
	if err != nil {
		return nil, err
	}

	// 判断给定日期是否最新
	if date == *currDate {
		var data domain.ShutdownStatisticsArea[[7]uint]
		err := cache.GetJSON(ctx, RedisKeyDashboardWeekly, &data)
		if err == nil {
			return &data, nil // 命中缓存
		}
	}

	shutdownDataList, err := handleWeeklyData(*currDate)
	if err != nil {
		return nil, err
	}

	// 缓存结果，只缓存最新日期
	if date == *currDate {
		cache.SetJSON(ctx, RedisKeyDashboardWeekly, shutdownDataList, time.Hour*24*7)
	}
	return shutdownDataList, nil
}

func getDashboardYearly(date string) (*domain.ShutdownStatisticsArea[[12]uint], error) {
	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
	defer cancel()

	// 未命中缓存 → 查询数据库
	currDate, err := getDashboardDate()
	if err != nil {
		return nil, err
	}

	t_currDate, err := time.Parse(time.DateOnly, *currDate)
	if err != nil {
		return nil, err
	}
	t_date, err := time.Parse(time.DateOnly, date)
	if err != nil {
		return nil, err
	}

	// 判断是否同年
	if t_currDate.Year() == t_date.Year() {
		var data domain.ShutdownStatisticsArea[[12]uint]
		err := cache.GetJSON(ctx, RedisKeyDashboardYearly, &data)
		if err == nil {
			return &data, nil // 命中缓存
		}
	}

	currDateTime, err := time.Parse(time.DateOnly, *currDate)
	if err != nil {
		zap.L().Error("getDashboardYearly currDate日期格式错误", zap.String("currDate", *currDate))
		return nil, err
	}

	shutdownDataList, err := handleYearlyData(currDateTime.Year())
	if err != nil {
		return nil, err
	}

	// 缓存结果
	if t_currDate.Year() == t_date.Year() {
		cache.SetJSON(ctx, RedisKeyDashboardYearly, shutdownDataList, time.Hour*24*365)
	}
	return shutdownDataList, nil
}

func handleWeeklyData(date string) (*domain.ShutdownStatisticsArea[[7]uint], error) {
	timeDate, err := time.Parse(time.DateOnly, date)
	if err != nil {
		zap.L().Error("handleWeeklyData日期格式错误", zap.String("date", date))
		return nil, err
	}

	// 计算6天前的日期
	startDate := timeDate.AddDate(0, 0, -6).Format(time.DateOnly)
	dataList, err := repositories.GetStatisticsShutdownByDateRange(startDate, date)
	if err != nil {
		zap.L().Error("GetStatisticsShutdownByDateRange error.", zap.String("err", err.Error()))
		return nil, err
	}

	var res domain.ShutdownStatisticsArea[[7]uint]
	for _, d := range dataList {
		t, err := time.Parse(time.DateOnly, d.Date)
		if err != nil {
			zap.L().Error("handleWeeklyData日期格式错误", zap.String("date", d.Date))
			return nil, err
		}
		diff := timeDate.Sub(t)
		// 转为天数（取整）
		days := int(diff.Hours() / 24)
		idx := 6 - days
		if idx < 0 || idx >= 7 {
			continue
		}

		res.ALL[idx] = d.Count.ALL
		res.US[idx] = d.Count.US
		res.AU[idx] = d.Count.AU
	}

	return &res, nil
}

func handleYearlyData(year int) (*domain.ShutdownStatisticsArea[[12]uint], error) {
	// 判断年份是否有效
	if year < 2000 || year > (time.Now().Year()+1) {
		return nil, fmt.Errorf("handleYearlyData年份不正确 year = %d", year)
	}

	var yearList domain.ShutdownStatisticsArea[[12]uint]
	for month := 1; month <= 12; month++ {
		// 每个月的第一天
		start := time.Date(year, time.Month(month), 1, 0, 0, 0, 0, time.Local)

		// 下个月的第一天再减1天 = 本月最后一天
		end := start.AddDate(0, 1, -1)

		// 获取月数据
		dataList, err := repositories.GetStatisticsShutdownByDateRange(start.Format(time.DateOnly), end.Format(time.DateOnly))
		if err != nil {
			zap.L().Error("GetStatisticsShutdownByDateRange error.", zap.String("err", err.Error()))
			return nil, err
		}

		// 计算月总数
		var monthCount domain.ShutdownStatisticsArea[uint]
		for _, d := range dataList {
			monthCount.ALL = monthCount.ALL + d.Count.ALL
			monthCount.US = monthCount.US + d.Count.US
			monthCount.AU = monthCount.AU + d.Count.AU
		}

		yearList.ALL[month-1] = monthCount.ALL
		yearList.US[month-1] = monthCount.US
		yearList.AU[month-1] = monthCount.AU
	}

	return &yearList, nil
}