//! 同步载荷应用：按业务键 upsert，仅当载荷新于本地时更新（last-write-wins）。 // Logan.Li

package sync

import (
	"fmt"
	"strings"
	"time"

	"backend/internal/dto"
	"backend/internal/model"
)

// upsertProduct 按产品 code 定位 // Logan.Li
func (s *Service) upsertProduct(p dto.SyncProductPayload) bool {
	if strings.TrimSpace(p.Code) == "" {
		return false
	}
	var local model.Product
	err := s.db.Where("code = ?", p.Code).First(&local).Error
	if err != nil {
		local = model.Product{
			Code: p.Code, Name: p.Name, Version: p.Version, Description: p.Description,
			Features: p.Features, Price: p.Price, PriceModel: p.PriceModel,
			Status: p.Status, CreatedAt: p.UpdatedAt, UpdatedAt: p.UpdatedAt,
		}
		return s.db.Create(&local).Error == nil
	}
	if !p.UpdatedAt.After(local.UpdatedAt) {
		return false // 本地已是最新的，跳过 // Logan.Li
	}
	local.Name = p.Name
	local.Version = p.Version
	local.Description = p.Description
	local.Features = p.Features
	local.Price = p.Price
	local.PriceModel = p.PriceModel
	local.Status = p.Status
	return s.db.Save(&local).Error == nil
}

// upsertPlan 按 产品code+plan_type+duration 定位 // Logan.Li
func (s *Service) upsertPlan(pl dto.SyncPlanPayload) bool {
	if pl.ProductCode == "" {
		return false
	}
	var product model.Product
	if err := s.db.Where("code = ?", pl.ProductCode).First(&product).Error; err != nil {
		return false // 产品依赖未就绪，等下一轮 // Logan.Li
	}
	var local model.Plan
	err := s.db.Where("product_id = ? AND plan_type = ? AND duration = ?", product.ID, pl.PlanType, pl.Duration).First(&local).Error
	if err != nil {
		local = model.Plan{
			ProductID: product.ID, Name: pl.Name, PlanType: pl.PlanType,
			Price: pl.Price, Currency: pl.Currency, Duration: pl.Duration,
			MaxDevices: pl.MaxDevices, Features: pl.Features, SortOrder: pl.SortOrder,
			Status: pl.Status, CreatedAt: pl.UpdatedAt, UpdatedAt: pl.UpdatedAt,
		}
		return s.db.Create(&local).Error == nil
	}
	if !pl.UpdatedAt.After(local.UpdatedAt) {
		return false
	}
	local.Name = pl.Name
	local.Price = pl.Price
	local.Currency = pl.Currency
	local.MaxDevices = pl.MaxDevices
	local.Features = pl.Features
	local.SortOrder = pl.SortOrder
	local.Status = pl.Status
	return s.db.Save(&local).Error == nil
}

// upsertCustomer 按 email 定位（空/占位邮箱回退 name），合规最小字段 // Logan.Li
func (s *Service) upsertCustomer(c dto.SyncCustomerPayload) bool {
	email := strings.TrimSpace(c.Email)
	name := strings.TrimSpace(c.Name)
	var local model.Customer
	var err error
	if email != "" && !strings.HasSuffix(email, "@local.invalid") {
		err = s.db.Where("email = ?", email).First(&local).Error
	} else {
		if name == "" {
			return false
		}
		err = s.db.Where("name = ?", name).Order("id ASC").First(&local).Error
	}
	if err != nil {
		if email == "" {
			email = fmt.Sprintf("sync+%d@local.invalid", time.Now().UnixNano())
		}
		local = model.Customer{
			Name: name, Company: c.Company, Email: email,
			Status: c.Status, CreatedAt: c.UpdatedAt, UpdatedAt: c.UpdatedAt,
		}
		return s.db.Create(&local).Error == nil
	}
	if !c.UpdatedAt.After(local.UpdatedAt) {
		return false
	}
	local.Name = name
	local.Company = c.Company
	if email != "" && !strings.HasSuffix(email, "@local.invalid") {
		local.Email = email
	}
	local.Status = c.Status
	return s.db.Save(&local).Error == nil
}

// upsertLicense 按 license_key 定位，跨表解析产品与客户 // Logan.Li
func (s *Service) upsertLicense(l dto.SyncLicensePayload) bool {
	if strings.TrimSpace(l.LicenseKey) == "" || l.ProductCode == "" {
		return false
	}
	var product model.Product
	if err := s.db.Where("code = ?", l.ProductCode).First(&product).Error; err != nil {
		return false
	}
	customerID, err := s.resolveCustomer(l.CustomerEmail, l.CustomerName)
	if err != nil {
		return false
	}
	var local model.License
	err = s.db.Where("license_key = ?", l.LicenseKey).First(&local).Error
	if err != nil {
		local = model.License{
			LicenseKey: l.LicenseKey, ProductID: product.ID, CustomerID: customerID,
			Status: l.Status, StartDate: l.StartDate, EndDate: l.EndDate,
			Duration: l.Duration, MaxActivations: l.MaxActivations,
			CurrentActivations: l.CurrentActivations,
			IsTrial:            l.IsTrial, TrialDays: l.TrialDays,
			CreatedAt: l.UpdatedAt, UpdatedAt: l.UpdatedAt,
		}
		return s.db.Create(&local).Error == nil
	}
	if !l.UpdatedAt.After(local.UpdatedAt) {
		return false
	}
	local.ProductID = product.ID
	local.CustomerID = customerID
	local.Status = l.Status
	local.StartDate = l.StartDate
	local.EndDate = l.EndDate
	local.Duration = l.Duration
	local.MaxActivations = l.MaxActivations
	local.CurrentActivations = l.CurrentActivations
	local.IsTrial = l.IsTrial
	local.TrialDays = l.TrialDays
	return s.db.Save(&local).Error == nil
}

// resolveCustomer 按邮箱解析或创建客户（离线占位客户按名字复用） // Logan.Li
func (s *Service) resolveCustomer(email, name string) (uint, error) {
	email = strings.TrimSpace(email)
	name = strings.TrimSpace(name)
	if email == "" {
		email = fmt.Sprintf("sync+%d@local.invalid", time.Now().UnixNano())
	}
	var customer model.Customer
	if err := s.db.Where("email = ?", email).First(&customer).Error; err == nil {
		return customer.ID, nil
	}
	customer = model.Customer{Name: name, Email: email, Status: 1}
	if err := s.db.Create(&customer).Error; err != nil {
		// 并发下可能已存在，再查一次 // Logan.Li
		if err2 := s.db.Where("email = ?", email).First(&customer).Error; err2 == nil {
			return customer.ID, nil
		}
		return 0, err
	}
	return customer.ID, nil
}