package main

import (
	"encoding/json"
	"fmt"
	"strings"
	"time"
)

// buy_records.go - 充值/缴费记录获取与缓存
// 接口: POST /app/electric/queryISIMSRoomBuyRecord
// 返回每笔充值记录(金额/类型/时间)，用于精确计算日耗电

// buyRecord 单笔充值记录
type buyRecord struct {
	Date   string  `json:"date"`    // 充值日期 YYYY-MM-DD
	Money  float64 `json:"money"`   // 充值金额(元)
	Kwh    float64 `json:"kwh"`     // 换算电量(度) = money / price
	Type   string  `json:"type"`    // 现金充值 / 下发补助
	Detail string  `json:"detail"`  // 完整时间 YYYY-M-D H:M:S
}

// 充值记录缓存
var (
	buyRecordsCache []buyRecord
	buyRecordsTime  int64
)

// queryBuyRecords 获取某房间的充值记录（需 application 域 shiroJID）
func queryBuyRecords(shiroJID string, room *roomInfo) ([]buyRecord, error) {
	price := unitPrice()
	s := newXfSession(shiroJID)
	body := fmt.Sprintf("areaId=%s&buildingCode=%s&floorCode=%s&roomCode=%s&mdtype=room&platform=%s",
		room.AreaID, room.BuildingCode, room.FloorCode, room.RoomCode, xfPlatform)
	b, _, err := s.postForm("https://application.xiaofubao.com/app/electric/queryISIMSRoomBuyRecord",
		body, "https://application.xiaofubao.com/")
	if err != nil {
		return nil, err
	}
	var res struct {
		StatusCode flexInt `json:"statusCode"`
		Rows       []struct {
			DateTime  string `json:"datetime"`   // "2026-8-23 0:45:49"
			BuyType   string `json:"buytype"`    // 现金充值 / 下发补助
			BuyUsing  string `json:"buyusingtpe"` // 照明用电
			Money     string `json:"money"`      // "40.00"
		} `json:"rows"`
	}
	if err := json.Unmarshal(b, &res); err != nil {
		return nil, err
	}
	if res.StatusCode != 0 {
		return nil, fmt.Errorf("queryISIMSRoomBuyRecord 失败: %s", string(b))
	}

	var records []buyRecord
	for _, r := range res.Rows {
		var money float64
		fmt.Sscanf(r.Money, "%f", &money)
		rec := buyRecord{
			Date:   datePart(r.DateTime),
			Money:  round2(money),
			Kwh:    round2(money / price),
			Type:   r.BuyType,
			Detail: r.DateTime,
		}
		records = append(records, rec)
	}
	return records, nil
}

// getBuyRecordsCached 获取充值记录（带缓存，10 分钟有效）
func getBuyRecordsCached(shiroJID string, room *roomInfo) ([]buyRecord, error) {
	if buyRecordsCache != nil && time.Now().Unix()-buyRecordsTime < 600 {
		return buyRecordsCache, nil
	}
	recs, err := queryBuyRecords(shiroJID, room)
	if err != nil {
		return nil, err
	}
	buyRecordsCache = recs
	buyRecordsTime = time.Now().Unix()
	return recs, nil
}

// rechargeKwhByDate 生成 map[date] -> 当天充值电量(度)
func rechargeKwhByDate(records []buyRecord) map[string]float64 {
	m := map[string]float64{}
	for _, r := range records {
		m[r.Date] = round2(m[r.Date] + r.Kwh)
	}
	return m
}

// unitPrice 电价（元/度），默认 0.535，可用 XF_PRICE 环境变量覆盖
func unitPrice() float64 {
	if v := envOr("XF_PRICE", ""); v != "" {
		var p float64
		if _, err := fmt.Sscanf(v, "%f", &p); err == nil && p > 0 {
			return p
		}
	}
	return 0.535
}

// datePart 从 "2026-8-23 0:45:49" 提取 "2026-08-23"
func datePart(dt string) string {
	parts := strings.SplitN(dt, " ", 2)
	if len(parts) == 0 {
		return dt
	}
	// 规范化月份/日补零
	ymd := strings.Split(parts[0], "-")
	if len(ymd) != 3 {
		return parts[0]
	}
	return fmt.Sprintf("%s-%02s-%02s", ymd[0], ymd[1], ymd[2])
}