package mohong

import (
	"context"
	"strings"

	"hfb_sys/backend/internal/model"

	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

const (
	configKeyDefaultQrcodeURL  = "mohong.default_qrcode_url"
	configKeyOrderCopyTemplate = "mohong.order_copy_template"

	defaultOrderCopyTemplate = "【撞车订单】\n订单号：{{order_no}}\n下单时间：{{created_at}}\n商品明细：\n{{items}}\n数量合计：{{quantity}}\n金额：{{amount}}\n下单人：{{buyer_name}}（{{buyer_phone}}）"
)

func (r *Repository) GetConfig(ctx context.Context) (*ConfigDTO, error) {
	if r.db == nil {
		return nil, ErrDependencyUnavailable
	}
	keys := []string{configKeyDefaultQrcodeURL, configKeyOrderCopyTemplate}
	var rows []model.SystemConfig
	if err := r.db.WithContext(ctx).Where("`key` IN ?", keys).Find(&rows).Error; err != nil {
		return nil, err
	}
	values := map[string]string{}
	for _, row := range rows {
		values[row.Key] = row.Value
	}
	return &ConfigDTO{
		DefaultQrcodeURL:  strings.TrimSpace(values[configKeyDefaultQrcodeURL]),
		OrderCopyTemplate: firstNonEmpty(values[configKeyOrderCopyTemplate], defaultOrderCopyTemplate),
	}, nil
}

func (r *Repository) UpdateConfig(ctx context.Context, req UpdateConfigRequest) (*ConfigDTO, error) {
	if r.db == nil {
		return nil, ErrDependencyUnavailable
	}
	err := r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		if req.DefaultQrcodeURL != nil {
			if err := upsertConfig(tx, configKeyDefaultQrcodeURL, strings.TrimSpace(*req.DefaultQrcodeURL), "撞车全局默认固定二维码图片URL"); err != nil {
				return err
			}
		}
		if req.OrderCopyTemplate != nil {
			if err := upsertConfig(tx, configKeyOrderCopyTemplate, strings.TrimSpace(*req.OrderCopyTemplate), "撞车订单一键复制文案模板"); err != nil {
				return err
			}
		}
		return nil
	})
	if err != nil {
		return nil, err
	}
	return r.GetConfig(ctx)
}

func upsertConfig(tx *gorm.DB, key, value, description string) error {
	row := model.SystemConfig{
		Key:         key,
		Value:       value,
		Description: description,
	}
	return tx.Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "key"}},
		DoUpdates: clause.AssignmentColumns([]string{"value", "description"}),
	}).Create(&row).Error
}

func firstNonEmpty(values ...string) string {
	for _, v := range values {
		if strings.TrimSpace(v) != "" {
			return strings.TrimSpace(v)
		}
	}
	return ""
}

func (r *Repository) resolveQrcodeURL(tx *gorm.DB, productQrcode string) string {
	productQrcode = strings.TrimSpace(productQrcode)
	if productQrcode != "" {
		return productQrcode
	}
	var cfg model.SystemConfig
	if err := tx.Where("`key` = ?", configKeyDefaultQrcodeURL).First(&cfg).Error; err == nil {
		return strings.TrimSpace(cfg.Value)
	}
	return ""
}

func (r *Repository) loadCopyTemplate(tx *gorm.DB) string {
	var cfg model.SystemConfig
	if err := tx.Where("`key` = ?", configKeyOrderCopyTemplate).First(&cfg).Error; err == nil && strings.TrimSpace(cfg.Value) != "" {
		return strings.TrimSpace(cfg.Value)
	}
	return defaultOrderCopyTemplate
}