package promo

import (
	"context"

	"github.com/redis/go-redis/v9"
	"gorm.io/gorm"
)

type RuleWithPrice struct {
	Rule
	PromoPrice int64 `gorm:"column:promo_price"`
}

type Model interface {
	QueryEligibleRules(ctx context.Context, subscribeId int64) ([]*RuleWithPrice, error)
	InsertUsage(ctx context.Context, data *Usage, tx ...*gorm.DB) error
}

type defaultPromoModel struct {
	db *gorm.DB
}

func NewModel(db *gorm.DB, _ *redis.Client) Model {
	return &defaultPromoModel{db: db}
}

func (m *defaultPromoModel) QueryEligibleRules(ctx context.Context, subscribeId int64) ([]*RuleWithPrice, error) {
	var list []*RuleWithPrice
	err := m.db.WithContext(ctx).
		Table("promo_rule AS pr").
		Select("pr.*, sp.promo_price").
		Joins("JOIN subscribe_promo AS sp ON sp.promo_rule_id = pr.id").
		Where("sp.subscribe_id = ? AND sp.promo_price > 0 AND pr.enabled = ?", subscribeId, true).
		Where("pr.deleted_at IS NULL").
		Order("pr.priority DESC").
		Order("pr.id ASC").
		Find(&list).Error
	return list, err
}

func (m *defaultPromoModel) InsertUsage(ctx context.Context, data *Usage, tx ...*gorm.DB) error {
	db := m.db.WithContext(ctx)
	if len(tx) > 0 {
		db = tx[0].WithContext(ctx)
	}
	return db.Model(&Usage{}).Create(data).Error
}