package repository

import (
	"context"

	"with_you/internal/dto"
	"with_you/internal/model"

	"gorm.io/gorm"
)

// OperationLogRepository 操作日志仓储接口
type OperationLogRepository interface {
	CreateOperationLog(ctx context.Context, log *model.OperationLog) error
	BatchCreateOperationLogs(ctx context.Context, logs []*model.OperationLog) error
	GetOperationLogs(ctx context.Context, filters dto.LogFilter, page, pageSize int) ([]*model.OperationLog, int64, error)
	GetOperationLogsByUser(ctx context.Context, userID string, page, pageSize int) ([]*model.OperationLog, int64, error)
	GetOperationLogsByTimeRange(ctx context.Context, startTime, endTime string, page, pageSize int) ([]*model.OperationLog, int64, error)
	DeleteOldLogs(ctx context.Context, beforeDate string) error
	GetStatistics(ctx context.Context, startTime, endTime string) (*OperationLogStatistics, error)
}

// operationLogRepository 操作日志仓储实现
type operationLogRepository struct {
	db *gorm.DB
}

// NewOperationLogRepository 创建操作日志仓储
func NewOperationLogRepository(db *gorm.DB) OperationLogRepository {
	return &operationLogRepository{db: db}
}

// CreateOperationLog 创建单条操作日志
func (r *operationLogRepository) CreateOperationLog(ctx context.Context, log *model.OperationLog) error {
	return r.db.WithContext(ctx).Create(log).Error
}

// BatchCreateOperationLogs 批量创建操作日志
func (r *operationLogRepository) BatchCreateOperationLogs(ctx context.Context, logs []*model.OperationLog) error {
	if len(logs) == 0 {
		return nil
	}
	return r.db.WithContext(ctx).Create(logs).Error
}

// GetOperationLogs 获取操作日志列表（分页）
func (r *operationLogRepository) GetOperationLogs(ctx context.Context, filters dto.LogFilter, page, pageSize int) ([]*model.OperationLog, int64, error) {
	query := r.db.WithContext(ctx).Model(&model.OperationLog{})

	if filters.UserID != "" {
		query = query.Where("user_id = ?", filters.UserID)
	}
	if filters.Operation != "" {
		query = query.Where("operation = ?", filters.Operation)
	}
	if filters.TargetType != "" {
		query = query.Where("target_type = ?", filters.TargetType)
	}
	if filters.TargetID != "" {
		query = query.Where("target_id = ?", filters.TargetID)
	}
	if filters.Status != "" {
		query = query.Where("status = ?", filters.Status)
	}
	if filters.StartTime != "" {
		query = query.Where("occurred_at >= ?", filters.StartTime)
	}
	if filters.EndTime != "" {
		query = query.Where("occurred_at <= ?", filters.EndTime)
	}
	if filters.IP != "" {
		query = query.Where("ip = ?", filters.IP)
	}

	var total int64
	if err := query.Count(&total).Error; err != nil {
		return nil, 0, err
	}

	var logs []*model.OperationLog
	offset := (page - 1) * pageSize
	if err := query.Order("occurred_at DESC").Offset(offset).Limit(pageSize).Find(&logs).Error; err != nil {
		return nil, 0, err
	}

	return logs, total, nil
}

// GetOperationLogsByUser 获取指定用户的操作日志
func (r *operationLogRepository) GetOperationLogsByUser(ctx context.Context, userID string, page, pageSize int) ([]*model.OperationLog, int64, error) {
	return r.GetOperationLogs(ctx, dto.LogFilter{UserID: userID}, page, pageSize)
}

// GetOperationLogsByTimeRange 按时间范围获取操作日志
func (r *operationLogRepository) GetOperationLogsByTimeRange(ctx context.Context, startTime, endTime string, page, pageSize int) ([]*model.OperationLog, int64, error) {
	return r.GetOperationLogs(ctx, dto.LogFilter{StartTime: startTime, EndTime: endTime}, page, pageSize)
}

// DeleteOldLogs 删除旧的操作日志（用于定时清理）
func (r *operationLogRepository) DeleteOldLogs(ctx context.Context, beforeDate string) error {
	return r.db.WithContext(ctx).Where("created_at < ?", beforeDate).Delete(&model.OperationLog{}).Error
}

// GetStatistics 获取操作日志统计（使用单次 GROUP BY 查询，避免多次 COUNT)
func (r *operationLogRepository) GetStatistics(ctx context.Context, startTime, endTime string) (*OperationLogStatistics, error) {
	stats := &OperationLogStatistics{}

	query := r.db.WithContext(ctx).Model(&model.OperationLog{})
	if startTime != "" {
		query = query.Where("created_at >= ?", startTime)
	}
	if endTime != "" {
		query = query.Where("created_at <= ?", endTime)
	}

	// 使用单次 GROUP BY 查询获取各状态计数
	type statusCount struct {
		Status string
		Count  int64
	}
	var results []statusCount
	err := query.Select("status, count(*) as count").Group("status").Scan(&results).Error
	if err != nil {
		return nil, err
	}

	// 汇总结果
	for _, r := range results {
		stats.TotalCount += r.Count
		switch r.Status {
		case "success":
			stats.SuccessCount = r.Count
		case "fail":
			stats.FailCount = r.Count
		}
	}

	return stats, nil
}

// OperationLogStatistics 操作日志统计
type OperationLogStatistics struct {
	TotalCount   int64
	SuccessCount int64
	FailCount    int64
}