package repository

import (
	"encoding/json"
	"time"
	"wails-app/internal/dao"
	"wails-app/internal/global"

	"gorm.io/gorm"
)

// appendEventLog 向事件日志 JSON 数组追加一条事件（沿用数字票 event_log 约定）。
func appendEventLog(log, eventJSON string) string {
	var events []map[string]interface{}
	json.Unmarshal([]byte(log), &events)
	var event map[string]interface{}
	json.Unmarshal([]byte(eventJSON), &event)
	events = append(events, event)
	data, _ := json.Marshal(events)
	return string(data)
}

type IncidentRepository struct{}

// Create 创建异常记录。
func (r *IncidentRepository) Create(record *dao.IncidentRecord) error {
	return global.GVA_DB.Create(record).Error
}

// GetByID 查询异常详情（含软删除过滤）。
func (r *IncidentRepository) GetByID(id uint) (*dao.IncidentRecord, error) {
	var record dao.IncidentRecord
	err := global.GVA_DB.First(&record, id).Error
	if err != nil {
		return nil, err
	}
	return &record, nil
}

// UpdateStateIfCurrent CAS 状态更新：仅当记录仍处于调用方观察到的状态时生效。
func (r *IncidentRepository) UpdateStateIfCurrent(id uint, fromStatus, toStatus string, updates map[string]interface{}) (bool, error) {
	if updates == nil {
		updates = make(map[string]interface{})
	}
	updates["status"] = toStatus
	result := global.GVA_DB.Model(&dao.IncidentRecord{}).
		Where("id = ? AND status = ?", id, fromStatus).
		Updates(updates)
	return result.RowsAffected == 1, result.Error
}

// UpdateIncidentID 建立异常与指令流水的双向关联（开闸失败场景）。
func (r *IncidentRepository) UpdateIncidentID(logID, incidentID uint) error {
	if logID == 0 || incidentID == 0 {
		return nil
	}
	return global.GVA_DB.Transaction(func(tx *gorm.DB) error {
		if err := tx.Model(&dao.DeviceCommandLog{}).
			Where("id = ?", logID).Update("incident_id", incidentID).Error; err != nil {
			return err
		}
		return tx.Model(&dao.IncidentRecord{}).
			Where("id = ?", incidentID).Update("gate_command_id", logID).Error
	})
}

// HasOpenDeviceOffline 同设备是否已有未关闭（待处理/处理中）的离线异常。
func (r *IncidentRepository) HasOpenDeviceOffline(deviceCode string) (bool, error) {
	if deviceCode == "" {
		return false, nil
	}
	var count int64
	err := global.GVA_DB.Model(&dao.IncidentRecord{}).
		Where("device_code = ? AND category = ? AND status IN (?, ?)",
			deviceCode, "device_offline", "pending", "processing").
		Count(&count).Error
	return count > 0, err
}

// ExistsRecent 通行类异常去重：同设备 + 同分类 + 同车辆标识，在时间窗口内不重复生成。
// 无车辆标识（车牌和 RFID 均为空）时不去重。
func (r *IncidentRepository) ExistsRecent(deviceCode, category, plateNumber, rfidTag string, minutes int) (bool, error) {
	if plateNumber == "" && rfidTag == "" {
		return false, nil
	}
	db := global.GVA_DB.Model(&dao.IncidentRecord{}).
		Where("device_code = ? AND category = ? AND status IN (?, ?) AND created_at >= ?",
			deviceCode, category, "pending", "processing", time.Now().Add(-time.Duration(minutes)*time.Minute))
	if plateNumber != "" {
		db = db.Where("plate_number = ?", plateNumber)
	} else {
		// GORM maps RFIDTag to rf_id_tag. Keep this condition model-based so it
		// cannot drift from the actual database column name.
		db = db.Where(&dao.IncidentRecord{RFIDTag: rfidTag})
	}
	var count int64
	err := db.Count(&count).Error
	return count > 0, err
}

// CreateCommandLog 写入指令流水。
func (r *IncidentRepository) CreateCommandLog(log *dao.DeviceCommandLog) error {
	return global.GVA_DB.Create(log).Error
}

// ResolveDeviceOfflineByDevice 设备恢复在线时批量关闭该设备未处理的离线异常。
func (r *IncidentRepository) ResolveDeviceOfflineByDevice(deviceCode, remark string) error {
	if deviceCode == "" {
		return nil
	}
	var open []dao.IncidentRecord
	if err := global.GVA_DB.Where("device_code = ? AND category = ? AND status IN (?, ?)",
		deviceCode, "device_offline", "pending", "processing").Find(&open).Error; err != nil {
		return err
	}
	now := time.Now()
	for i := range open {
		event, _ := json.Marshal(map[string]interface{}{
			"event": "resolved", "handle_type": "device_repaired", "remark": remark, "at": now.Format(time.RFC3339),
		})
		if err := global.GVA_DB.Model(&open[i]).Updates(map[string]interface{}{
			"status": "resolved", "handle_type": "device_repaired",
			"handled_at": now, "handle_remark": remark, "handler_id": 0,
			"event_log": appendEventLog(open[i].EventLog, string(event)),
		}).Error; err != nil {
			return err
		}
	}
	return nil
}

type IncidentListQuery struct {
	Status       string `form:"status"`
	Category     string `form:"category"`
	Level        string `form:"level"`
	Source       string `form:"source"`
	PlateNumber  string `form:"plate_number"`
	TicketNo     string `form:"ticket_no"`
	ParkingLotID uint   `form:"parking_lot_id"`
	DeviceCode   string `form:"device_code"`
	StartDate    string `form:"start_date"`
	EndDate      string `form:"end_date"`
	Page         int    `form:"page"`
	PageSize     int    `form:"page_size"`
}

type IncidentListItem struct {
	dao.IncidentRecord
	OperatorName string `json:"operator_name"`
	HandlerName  string `json:"handler_name"`
	LotName      string `json:"lot_name"`
}

// List 分页筛选异常记录（上报人/处理人昵称、停车场名称联查）。
func (r *IncidentRepository) List(q IncidentListQuery) ([]IncidentListItem, int64, error) {
	db := global.GVA_DB.Table("incident_record ir").
		Select("ir.*, op.nick_name as operator_name, hd.nick_name as handler_name, COALESCE(ir.parking_lot_name, pl.lot_name) as lot_name").
		Joins("LEFT JOIN sys_users op ON op.id = ir.operator_id").
		Joins("LEFT JOIN sys_users hd ON hd.id = ir.handler_id").
		Joins("LEFT JOIN parking_lot pl ON pl.id = ir.parking_lot_id")

	if q.Status != "" {
		db = db.Where("ir.status = ?", q.Status)
	}
	if q.Category != "" {
		db = db.Where("ir.category = ?", q.Category)
	}
	if q.Level != "" {
		db = db.Where("ir.level = ?", q.Level)
	}
	if q.Source != "" {
		db = db.Where("ir.source = ?", q.Source)
	}
	if q.PlateNumber != "" {
		db = db.Where("ir.plate_number LIKE ?", "%"+q.PlateNumber+"%")
	}
	if q.TicketNo != "" {
		db = db.Where("ir.ticket_no LIKE ?", "%"+q.TicketNo+"%")
	}
	if q.ParkingLotID > 0 {
		db = db.Where("ir.parking_lot_id = ?", q.ParkingLotID)
	}
	if q.DeviceCode != "" {
		db = db.Where("ir.device_code LIKE ?", "%"+q.DeviceCode+"%")
	}
	if q.StartDate != "" {
		db = db.Where("ir.created_at >= ?", q.StartDate+" 00:00:00")
	}
	if q.EndDate != "" {
		db = db.Where("ir.created_at < ?", q.EndDate+" 23:59:59")
	}

	var total int64
	db.Count(&total)

	if q.Page <= 0 {
		q.Page = 1
	}
	if q.PageSize <= 0 {
		q.PageSize = 10
	}
	var list []IncidentListItem
	err := db.Order("ir.id DESC").Offset((q.Page - 1) * q.PageSize).Limit(q.PageSize).Scan(&list).Error
	return list, total, err
}

type IncidentStats struct {
	Pending              int64   `json:"pending"`
	Processing           int64   `json:"processing"`
	Resolved             int64   `json:"resolved"`
	Closed               int64   `json:"closed"`
	TodayCreated         int64   `json:"today_created"`
	OpenFundRelated      int64   `json:"open_fund_related"`
	TodayForceFreeAmount float64 `json:"today_force_free_amount"`
}

// Stats 异常统计：状态分布、今日新增、未关闭资金类数量、今日强制免费金额。
func (r *IncidentRepository) Stats() (IncidentStats, error) {
	var stats IncidentStats
	// 每次 Count 使用全新的查询构建器，避免 GORM Where 条件在复用实例上累积
	base := func() *gorm.DB {
		return global.GVA_DB.Model(&dao.IncidentRecord{})
	}
	if err := base().Where("status = ?", "pending").Count(&stats.Pending).Error; err != nil {
		return stats, err
	}
	if err := base().Where("status = ?", "processing").Count(&stats.Processing).Error; err != nil {
		return stats, err
	}
	if err := base().Where("status = ?", "resolved").Count(&stats.Resolved).Error; err != nil {
		return stats, err
	}
	if err := base().Where("status = ?", "closed").Count(&stats.Closed).Error; err != nil {
		return stats, err
	}
	if err := base().Where("created_at >= ?", startOfDay()).Count(&stats.TodayCreated).Error; err != nil {
		return stats, err
	}
	// 资金相关分类（支付失败/不确定、开闸失败、无入场记录出场）中未关闭的数量
	if err := base().Where("status IN (?, ?) AND category IN (?, ?, ?, ?)",
		"pending", "processing",
		"payment_failed", "payment_uncertain", "gate_failed", "no_entry_exit").
		Count(&stats.OpenFundRelated).Error; err != nil {
		return stats, err
	}
	// 今日强制免费金额合计
	if err := global.GVA_DB.Model(&dao.IncidentRecord{}).
		Where("handle_type = ? AND handled_at >= ?", "force_free", startOfDay()).
		Select("COALESCE(SUM(force_free_amount), 0)").Scan(&stats.TodayForceFreeAmount).Error; err != nil {
		return stats, err
	}
	return stats, nil
}

func startOfDay() time.Time {
	now := time.Now()
	return time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, now.Location())
}