// Package house_dashboard 提供看房数据看板聚合服务。
package house_dashboard

import (
	"context"

	"github.com/gogf/gf/v2/errors/gerror"

	"service.xpcool.com/internal/dao"
	"service.xpcool.com/internal/model/dto"
)

// IDashboard 看板聚合领域服务接口。
type IDashboard interface {
	Overview(context.Context, string) (dto.DashboardOverview, error)
	MapPoints(context.Context, string, float64, float64, int) ([]dto.DashboardMapPoint, error)
	PriceTrend(context.Context, uint64, string, int) ([]dto.DashboardTrendPoint, error)
	AggregateRegion(context.Context) ([]dto.DashboardRegionAgg, error)
}

type dashboard struct{}

var localDashboard IDashboard

func NewDashboard() IDashboard { return &dashboard{} }

// Dashboard 返回已注册的看板服务实现。
func Dashboard() IDashboard {
	if localDashboard == nil {
		panic("Dashboard 实现未注册")
	}
	return localDashboard
}

// RegisterDashboard 注册看板服务实现。
func RegisterDashboard(i IDashboard) { localDashboard = i }

// Overview 统计概览：小区数、在售房源、笋盘、低可信、均价、平均挂牌天数。
func (s *dashboard) Overview(ctx context.Context, region string) (dto.DashboardOverview, error) {
	var out dto.DashboardOverview
	cm := dao.HouseCommunity.Ctx(ctx)
	if region != "" {
		cm = cm.Where("region", region)
	}
	cnt, err := cm.Count()
	if err != nil {
		return out, gerror.Wrap(err, "统计小区总数失败")
	}
	out.CommunityCount = cnt

	// 房源相关指标统一经小区联表，支持按区域过滤。
	lm := dao.HouseListing.Ctx(ctx).As("l").LeftJoin("house_community c", "l.community_id=c.id")
	if region != "" {
		lm = lm.Where("c.region", region)
	}
	out.ListingCount, _ = lm.Clone().Where("l.status", 1).Count()
	out.BargainCount, _ = lm.Clone().Where("l.is_bargain", 1).Count()
	out.LowConfidence, _ = lm.Clone().Where("l.confidence", 1).Count()

	var agg struct {
		AvgUnitPrice  float64 `orm:"avg_unit_price"`
		AvgTotalPrice float64 `orm:"avg_total_price"`
		AvgListDays   float64 `orm:"avg_list_days"`
	}
	if err := lm.Clone().Where("l.status", 1).Fields(
		"COALESCE(AVG(l.unit_price),0) AS avg_unit_price, COALESCE(AVG(l.total_price),0) AS avg_total_price, COALESCE(AVG(l.on_market_days),0) AS avg_list_days",
	).Scan(&agg); err != nil {
		return out, gerror.Wrap(err, "聚合概览指标失败")
	}
	out.AvgUnitPrice = agg.AvgUnitPrice
	out.AvgTotalPrice = agg.AvgTotalPrice
	out.AvgListDays = agg.AvgListDays
	return out, nil
}

// MapPoints 地图点位：按小区聚合均价与在售/笋盘数量。
func (s *dashboard) MapPoints(ctx context.Context, region string, priceMin, priceMax float64, status int) ([]dto.DashboardMapPoint, error) {
	m := dao.HouseListing.Ctx(ctx).As("l").
		LeftJoin("house_community c", "l.community_id=c.id").
		Fields("l.community_id AS community_id, c.name AS name, c.region AS region, c.lng AS lng, c.lat AS lat, COALESCE(AVG(l.unit_price),0) AS avg_unit_price, COUNT(*) AS listing_count, COALESCE(SUM(l.is_bargain),0) AS bargain_count").
		Group("l.community_id, c.name, c.region, c.lng, c.lat")
	if region != "" {
		m = m.Where("c.region", region)
	}
	if priceMin > 0 {
		m = m.WhereGTE("l.total_price", priceMin)
	}
	if priceMax > 0 {
		m = m.WhereLTE("l.total_price", priceMax)
	}
	if status > 0 {
		m = m.Where("l.status", status)
	}
	var list []dto.DashboardMapPoint
	if err := m.Scan(&list); err != nil {
		return nil, gerror.Wrap(err, "查询地图点位失败")
	}
	return list, nil
}

// PriceTrend 价格趋势：按快照日期聚合挂牌/成交均价，返回时间升序。
func (s *dashboard) PriceTrend(ctx context.Context, communityId uint64, region string, limit int) ([]dto.DashboardTrendPoint, error) {
	m := dao.HousePriceSnapshot.Ctx(ctx).As("p")
	if communityId > 0 {
		m = m.Where("p.community_id", communityId)
	}
	if region != "" {
		m = m.LeftJoin("house_community c", "p.community_id=c.id").Where("c.region", region)
	}
	m = m.Fields("p.snap_date AS date, COALESCE(AVG(p.list_price),0) AS avg_list_price, COALESCE(AVG(p.deal_price),0) AS avg_deal_price").
		Group("p.snap_date").
		OrderDesc("p.snap_date")
	if limit > 0 {
		m = m.Limit(limit)
	}
	var list []dto.DashboardTrendPoint
	if err := m.Scan(&list); err != nil {
		return nil, gerror.Wrap(err, "查询价格趋势失败")
	}
	// 反转为时间升序，便于前端画趋势线。
	for i, j := 0, len(list)-1; i < j; i, j = i+1, j-1 {
		list[i], list[j] = list[j], list[i]
	}
	return list, nil
}

// AggregateRegion 区域聚合：按区县统计在售均价与数量。
func (s *dashboard) AggregateRegion(ctx context.Context) ([]dto.DashboardRegionAgg, error) {
	m := dao.HouseListing.Ctx(ctx).As("l").
		LeftJoin("house_community c", "l.community_id=c.id").
		Fields("c.region AS region, COALESCE(AVG(l.unit_price),0) AS avg_unit_price, COUNT(*) AS listing_count, COALESCE(SUM(l.is_bargain),0) AS bargain_count").
		Where("l.status", 1).
		WhereGT("c.region", "").
		Group("c.region").
		OrderAsc("c.region")
	var list []dto.DashboardRegionAgg
	if err := m.Scan(&list); err != nil {
		return nil, gerror.Wrap(err, "查询区域聚合失败")
	}
	return list, nil
}