// Package pollingalert 是失败告警"停机被拒"视图的只读查询，供后台列表与导出共用（add-polling-pause-list-and-batch-toggle）。
package pollingalert

import (
	"context"
	"time"

	"gorm.io/gorm"

	"github.com/break/junhong_cmp_fiber/pkg/constants"
	"github.com/break/junhong_cmp_fiber/pkg/errors"
)

// StopRefusedFilter 是停机被拒视图的附加筛选。
type StopRefusedFilter struct {
	CarrierID *uint
	Status    *int
	ICCID     string
	StartTime *time.Time
	EndTime   *time.Time
}

// StopRefusedRow 是停机被拒告警与卡当前状态的投影。
type StopRefusedRow struct {
	ID            uint
	CardID        uint
	ICCID         string
	CarrierID     uint
	CarrierName   string
	DeviceID      uint
	NetworkStatus int
	StopReason    string
	EnablePolling bool
	HasPackage    bool
	ErrorCategory string
	FailCount     int
	FirstFailedAt *time.Time
	LastFailedAt  *time.Time
	LastError     string
	Status        int
	HandledBy     uint
	HandledByName string
	HandledAt     *time.Time
	HandleRemark  string
}

// ApplyStopRefused 在告警查询上叠加"停机被拒"视图条件：停复机方向为停机，且错误类型为终态或业务错误、或停机失败次数达到阈值。
// 停复机方向告警的最近错误以 "stop: " 开头（见停复机指令执行器）。
func ApplyStopRefused(query *gorm.DB, table string, threshold int) *gorm.DB {
	if threshold <= 0 {
		threshold = 5
	}
	prefix := ""
	if table != "" {
		prefix = table + "."
	}
	return query.Where(prefix+"alert_level = ? AND "+prefix+"check_type = ? AND "+prefix+"last_error LIKE ?",
		constants.PollingAlertLevelCard, constants.CheckTypeStopResume, constants.StopResumeActionStop+":%").
		Where("("+prefix+"error_category IN ? OR "+prefix+"fail_count >= ?)",
			[]string{constants.GatewayClassTerminal, constants.GatewayClassBusiness}, threshold)
}

// Query 停机被拒视图查询。
type Query struct {
	db *gorm.DB
}

// NewQuery 创建停机被拒视图查询。
func NewQuery(db *gorm.DB) *Query {
	return &Query{db: db}
}

func (q *Query) base(ctx context.Context, filter StopRefusedFilter, threshold int) *gorm.DB {
	query := ApplyStopRefused(q.db.WithContext(ctx).Table("tb_polling_failure_alert AS a"), "a", threshold)
	if filter.CarrierID != nil {
		query = query.Where("a.carrier_id = ?", *filter.CarrierID)
	}
	if filter.Status != nil {
		query = query.Where("a.status = ?", *filter.Status)
	}
	if filter.ICCID != "" {
		query = query.Where("a.iccid = ?", filter.ICCID)
	}
	if filter.StartTime != nil {
		query = query.Where("a.last_failed_at >= ?", *filter.StartTime)
	}
	if filter.EndTime != nil {
		query = query.Where("a.last_failed_at <= ?", *filter.EndTime)
	}
	return query
}

// Count 统计停机被拒告警数。
func (q *Query) Count(ctx context.Context, filter StopRefusedFilter, threshold int) (int64, error) {
	var total int64
	if err := q.base(ctx, filter, threshold).Count(&total).Error; err != nil {
		return 0, errors.Wrap(errors.CodeDatabaseError, err, "统计停机被拒告警失败")
	}
	return total, nil
}

// Page 返回一页停机被拒告警，附带所属设备、网络状态、停机原因、轮询开关、是否有生效套餐与处理人。
func (q *Query) Page(ctx context.Context, filter StopRefusedFilter, threshold, offset, limit int) ([]StopRefusedRow, error) {
	var rows []StopRefusedRow
	err := q.base(ctx, filter, threshold).
		Select(`a.id, a.card_id, a.iccid, a.carrier_id, COALESCE(ca.carrier_name, '') AS carrier_name,
			COALESCE(b.device_id, 0) AS device_id, COALESCE(c.network_status, 0) AS network_status,
			COALESCE(c.stop_reason, '') AS stop_reason, COALESCE(c.enable_polling, FALSE) AS enable_polling,
			EXISTS (SELECT 1 FROM tb_package_usage u WHERE u.status = ? AND u.master_usage_id IS NULL AND u.deleted_at IS NULL
				AND ((b.device_id IS NOT NULL AND u.device_id = b.device_id) OR (b.device_id IS NULL AND u.iot_card_id = a.card_id))) AS has_package,
			a.error_category, a.fail_count, a.first_failed_at, a.last_failed_at, a.last_error, a.status,
			a.handled_by, COALESCE(ac.username, '') AS handled_by_name, a.handled_at, a.handle_remark`, constants.PackageUsageStatusActive).
		Joins("LEFT JOIN tb_iot_card c ON c.id = a.card_id").
		Joins("LEFT JOIN tb_device_sim_binding b ON b.iot_card_id = a.card_id AND b.bind_status = ? AND b.deleted_at IS NULL", constants.BindStatusBound).
		Joins("LEFT JOIN tb_carrier ca ON ca.id = a.carrier_id").
		Joins("LEFT JOIN tb_account ac ON ac.id = a.handled_by").
		Order("a.last_failed_at DESC NULLS LAST, a.id DESC").Offset(offset).Limit(limit).Scan(&rows).Error
	if err != nil {
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询停机被拒告警失败")
	}
	return rows, nil
}