package product

import (
	"errors"
	productv1 "gitea.timerzz.com/kedaya_haitao/common/model/product"
	"github.com/samber/lo"
	"gorm.io/gorm"
)

const (
	USCoachOutletPid = "us-coach-outlet"
)

var (
	defaultCalculateProcesses = []productv1.CalculateProcess{
		{
			Pid:     USCoachOutletPid,
			Name:    "九折",
			Process: "originalPrice * 0.9 * exchangeRate + freight",
		},
		{
			Pid:       USCoachOutletPid,
			Name:      "150 - 20",
			Condition: "originalPrice >= 150",
			Process:   "(originalPrice - 20) * exchangeRate + freight",
		},
		{
			Pid:       USCoachOutletPid,
			Name:      "100 - 10",
			Condition: "originalPrice >= 100",
			Process:   "(originalPrice - 10) * exchangeRate + freight",
		},
	}
)

func (c *Controller) LoadCalculateProcess() {
	c.db.Model(&productv1.CalculateProcess{}).Find(&c.calculates, "pid = ?", USCoachOutletPid)
	if len(c.calculates) == 0 {
		c.db.Create(&defaultCalculateProcesses)
		c.db.Model(&productv1.CalculateProcess{}).Find(&c.calculates, "pid = ?", USCoachOutletPid)
	}
}

func (c *Controller) GetGlobalCalculateProcess() (cs []productv1.CalculateProcess, err error) {
	err = c.db.Model(&productv1.CalculateProcess{}).Find(&cs, "pid = ?", USCoachOutletPid).Error
	return
}

// DeleteGlobalCalculateProcess 删除全局的计算规则
func (c *Controller) DeleteGlobalCalculateProcess(id uint) error {
	if _, idx, exist := lo.FindIndexOf(c.calculates, func(item productv1.CalculateProcess) bool {
		return item.ID == id
	}); exist {
		if err := c.db.Model(&productv1.CalculateProcess{}).Delete(&c.calculates[idx], "id = ?", id).Error; err != nil {
			return err
		}
		c.calculates = append(c.calculates[:idx], c.calculates[idx+1:]...)
		go c.updateRate(c.Freight)
	}
	return nil
}

// SaveGlobalCalculateProcess 更新全局的计算规则
func (c *Controller) SaveGlobalCalculateProcess(cs []productv1.CalculateProcess) error {
	if len(cs) == 0 {
		return nil
	}
	cs = lo.Filter(cs, func(item productv1.CalculateProcess, index int) bool {
		return item.Pid == USCoachOutletPid
	})
	return c.db.Transaction(func(tx *gorm.DB) error {
		if err := c.db.Save(&cs).Error; err != nil {
			return err
		}

		if err := c.db.Model(&productv1.CalculateProcess{}).Find(&c.calculates, "pid = ?", USCoachOutletPid).Error; err != nil {
			return err
		}
		go c.updateRate(c.Freight)
		return nil
	})
}

// DeleteCalculateProcess 删除计算规则
func (c *Controller) DeleteCalculateProcess(id uint) error {
	return c.db.Transaction(func(tx *gorm.DB) error {
		cal := productv1.CalculateProcess{}
		if err := tx.Model(&productv1.CalculateProcess{}).Where("id = ?", id).First(&cal).Error; err != nil && !errors.As(err, &gorm.ErrRecordNotFound) {
			return err
		} else if errors.As(err, &gorm.ErrRecordNotFound) {
			return nil
		}

		if err := tx.Model(&productv1.CalculateProcess{}).Where("id = ?", cal.ID).Delete(&cal).Error; err != nil {
			return err
		}
		var product productv1.Product
		if err := tx.Preload("CalculateProcess").First(&product, "pid = ? AND website = ?", cal.Pid, productv1.WebSite_US_Coach_Outlet).Error; err != nil {
			return err
		}
		product.ExchangeRate = c.ExchangeRate
		product.CalCNY(append(product.CalculateProcess, c.calculates...))
		return tx.Model(&product).Where("pid = ? AND website = ?", product.Pid, productv1.WebSite_US_Coach_Outlet).Select("rate", "cal_mark", "cny_price").Updates(&product).Error
	})
}

// SaveCalculateProcess 更新计算规则
func (c *Controller) SaveCalculateProcess(cs []productv1.CalculateProcess) error {
	if len(cs) == 0 {
		return nil
	}

	return c.db.Transaction(func(tx *gorm.DB) error {
		if err := c.db.Save(&cs).Error; err != nil {
			return err
		}

		var product productv1.Product
		if err := tx.Preload("CalculateProcess").First(&product, "pid = ? AND website = ?", cs[0].Pid, productv1.WebSite_US_Coach_Outlet).Error; err != nil {
			return err
		}
		product.ExchangeRate = c.ExchangeRate
		product.CalCNY(append(product.CalculateProcess, c.calculates...))
		return tx.Model(&product).Where("pid = ? AND website = ?", product.Pid, productv1.WebSite_US_Coach_Outlet).Select("rate", "cal_mark", "cny_price").Updates(&product).Error
	})
}