package customer_account

import (
	"context"
	"fmt"

	"github.com/break/junhong_cmp_fiber/internal/model"
	"github.com/break/junhong_cmp_fiber/internal/model/dto"
	"github.com/break/junhong_cmp_fiber/internal/store/postgres"
	"github.com/break/junhong_cmp_fiber/pkg/constants"
	"github.com/break/junhong_cmp_fiber/pkg/errors"
	"github.com/break/junhong_cmp_fiber/pkg/middleware"
	"golang.org/x/crypto/bcrypt"
	"gorm.io/gorm"
)

type Service struct {
	db              *gorm.DB
	accountStore    *postgres.AccountStore
	shopStore       *postgres.ShopStore
	enterpriseStore *postgres.EnterpriseStore
}

func New(
	db *gorm.DB,
	accountStore *postgres.AccountStore,
	shopStore *postgres.ShopStore,
	enterpriseStore *postgres.EnterpriseStore,
) *Service {
	return &Service{
		db:              db,
		accountStore:    accountStore,
		shopStore:       shopStore,
		enterpriseStore: enterpriseStore,
	}
}

func (s *Service) List(ctx context.Context, req *dto.CustomerAccountListReq) (*dto.CustomerAccountPageResult, error) {
	page := req.Page
	pageSize := req.PageSize
	if page == 0 {
		page = 1
	}
	if pageSize == 0 {
		pageSize = constants.DefaultPageSize
	}

	query := s.db.WithContext(ctx).Model(&model.Account{}).
		Where("user_type IN ?", []int{constants.UserTypeAgent, constants.UserTypeEnterprise})

	if req.Username != "" {
		query = query.Where("username LIKE ?", "%"+req.Username+"%")
	}
	if req.Phone != "" {
		query = query.Where("phone LIKE ?", "%"+req.Phone+"%")
	}
	if req.UserType != nil {
		query = query.Where("user_type = ?", *req.UserType)
	}
	if req.ShopID != nil {
		query = query.Where("shop_id = ?", *req.ShopID)
	}
	if req.EnterpriseID != nil {
		query = query.Where("enterprise_id = ?", *req.EnterpriseID)
	}
	if req.Status != nil {
		query = query.Where("status = ?", *req.Status)
	}

	var total int64
	if err := query.Count(&total).Error; err != nil {
		return nil, fmt.Errorf("统计账号数量失败: %w", err)
	}

	var accounts []model.Account
	offset := (page - 1) * pageSize
	if err := query.Offset(offset).Limit(pageSize).Order("created_at DESC").Find(&accounts).Error; err != nil {
		return nil, fmt.Errorf("查询账号列表失败: %w", err)
	}

	shopIDs := make([]uint, 0)
	enterpriseIDs := make([]uint, 0)
	for _, acc := range accounts {
		if acc.ShopID != nil {
			shopIDs = append(shopIDs, *acc.ShopID)
		}
		if acc.EnterpriseID != nil {
			enterpriseIDs = append(enterpriseIDs, *acc.EnterpriseID)
		}
	}

	shopMap := make(map[uint]string)
	if len(shopIDs) > 0 {
		var shops []model.Shop
		s.db.WithContext(ctx).Where("id IN ?", shopIDs).Find(&shops)
		for _, shop := range shops {
			shopMap[shop.ID] = shop.ShopName
		}
	}

	enterpriseMap := make(map[uint]string)
	if len(enterpriseIDs) > 0 {
		var enterprises []model.Enterprise
		s.db.WithContext(ctx).Where("id IN ?", enterpriseIDs).Find(&enterprises)
		for _, ent := range enterprises {
			enterpriseMap[ent.ID] = ent.EnterpriseName
		}
	}

	items := make([]dto.CustomerAccountItem, 0, len(accounts))
	for _, acc := range accounts {
		shopName := ""
		if acc.ShopID != nil {
			shopName = shopMap[*acc.ShopID]
		}
		enterpriseName := ""
		if acc.EnterpriseID != nil {
			enterpriseName = enterpriseMap[*acc.EnterpriseID]
		}
		items = append(items, dto.CustomerAccountItem{
			ID:             acc.ID,
			Username:       acc.Username,
			Phone:          acc.Phone,
			UserType:       acc.UserType,
			UserTypeName:   getUserTypeName(acc.UserType),
			ShopID:         acc.ShopID,
			ShopName:       shopName,
			EnterpriseID:   acc.EnterpriseID,
			EnterpriseName: enterpriseName,
			Status:         acc.Status,
			StatusName:     getStatusName(acc.Status),
			CreatedAt:      acc.CreatedAt.Format("2006-01-02 15:04:05"),
		})
	}

	return &dto.CustomerAccountPageResult{
		Items: items,
		Total: total,
		Page:  page,
		Size:  pageSize,
	}, nil
}

func (s *Service) Create(ctx context.Context, req *dto.CreateCustomerAccountReq) (*dto.CustomerAccountItem, error) {
	currentUserID := middleware.GetUserIDFromContext(ctx)
	if currentUserID == 0 {
		return nil, errors.New(errors.CodeUnauthorized, "未授权访问")
	}

	_, err := s.shopStore.GetByID(ctx, req.ShopID)
	if err != nil {
		return nil, errors.New(errors.CodeShopNotFound, "店铺不存在")
	}

	existingAccount, _ := s.accountStore.GetByPhone(ctx, req.Phone)
	if existingAccount != nil {
		return nil, errors.New(errors.CodePhoneExists, "手机号已被使用")
	}

	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
	if err != nil {
		return nil, fmt.Errorf("密码加密失败: %w", err)
	}

	account := &model.Account{
		Username: req.Username,
		Phone:    req.Phone,
		Password: string(hashedPassword),
		UserType: constants.UserTypeAgent,
		ShopID:   &req.ShopID,
		Status:   constants.StatusEnabled,
	}
	account.Creator = currentUserID
	account.Updater = currentUserID

	if err := s.db.WithContext(ctx).Create(account).Error; err != nil {
		return nil, fmt.Errorf("创建账号失败: %w", err)
	}

	shop, _ := s.shopStore.GetByID(ctx, req.ShopID)
	shopName := ""
	if shop != nil {
		shopName = shop.ShopName
	}

	return &dto.CustomerAccountItem{
		ID:           account.ID,
		Username:     account.Username,
		Phone:        account.Phone,
		UserType:     account.UserType,
		UserTypeName: getUserTypeName(account.UserType),
		ShopID:       account.ShopID,
		ShopName:     shopName,
		Status:       account.Status,
		StatusName:   getStatusName(account.Status),
		CreatedAt:    account.CreatedAt.Format("2006-01-02 15:04:05"),
	}, nil
}

func (s *Service) Update(ctx context.Context, id uint, req *dto.UpdateCustomerAccountRequest) (*dto.CustomerAccountItem, error) {
	currentUserID := middleware.GetUserIDFromContext(ctx)
	if currentUserID == 0 {
		return nil, errors.New(errors.CodeUnauthorized, "未授权访问")
	}

	account, err := s.accountStore.GetByID(ctx, id)
	if err != nil {
		return nil, errors.New(errors.CodeAccountNotFound, "账号不存在")
	}

	if account.UserType != constants.UserTypeAgent && account.UserType != constants.UserTypeEnterprise {
		return nil, errors.New(errors.CodeForbidden, "无权限操作此账号")
	}

	if req.Username != nil {
		account.Username = *req.Username
	}
	if req.Phone != nil {
		if *req.Phone != account.Phone {
			existingAccount, _ := s.accountStore.GetByPhone(ctx, *req.Phone)
			if existingAccount != nil && existingAccount.ID != id {
				return nil, errors.New(errors.CodePhoneExists, "手机号已被使用")
			}
			account.Phone = *req.Phone
		}
	}
	account.Updater = currentUserID

	if err := s.db.WithContext(ctx).Save(account).Error; err != nil {
		return nil, fmt.Errorf("更新账号失败: %w", err)
	}

	shopName := ""
	if account.ShopID != nil {
		if shop, _ := s.shopStore.GetByID(ctx, *account.ShopID); shop != nil {
			shopName = shop.ShopName
		}
	}
	enterpriseName := ""
	if account.EnterpriseID != nil {
		if ent, _ := s.enterpriseStore.GetByID(ctx, *account.EnterpriseID); ent != nil {
			enterpriseName = ent.EnterpriseName
		}
	}

	return &dto.CustomerAccountItem{
		ID:             account.ID,
		Username:       account.Username,
		Phone:          account.Phone,
		UserType:       account.UserType,
		UserTypeName:   getUserTypeName(account.UserType),
		ShopID:         account.ShopID,
		ShopName:       shopName,
		EnterpriseID:   account.EnterpriseID,
		EnterpriseName: enterpriseName,
		Status:         account.Status,
		StatusName:     getStatusName(account.Status),
		CreatedAt:      account.CreatedAt.Format("2006-01-02 15:04:05"),
	}, nil
}

func (s *Service) UpdatePassword(ctx context.Context, id uint, password string) error {
	currentUserID := middleware.GetUserIDFromContext(ctx)
	if currentUserID == 0 {
		return errors.New(errors.CodeUnauthorized, "未授权访问")
	}

	account, err := s.accountStore.GetByID(ctx, id)
	if err != nil {
		return errors.New(errors.CodeAccountNotFound, "账号不存在")
	}

	if account.UserType != constants.UserTypeAgent && account.UserType != constants.UserTypeEnterprise {
		return errors.New(errors.CodeForbidden, "无权限操作此账号")
	}

	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
	if err != nil {
		return fmt.Errorf("密码加密失败: %w", err)
	}

	return s.db.WithContext(ctx).Model(&model.Account{}).
		Where("id = ?", id).
		Updates(map[string]interface{}{
			"password": string(hashedPassword),
			"updater":  currentUserID,
		}).Error
}

func (s *Service) UpdateStatus(ctx context.Context, id uint, status int) error {
	currentUserID := middleware.GetUserIDFromContext(ctx)
	if currentUserID == 0 {
		return errors.New(errors.CodeUnauthorized, "未授权访问")
	}

	account, err := s.accountStore.GetByID(ctx, id)
	if err != nil {
		return errors.New(errors.CodeAccountNotFound, "账号不存在")
	}

	if account.UserType != constants.UserTypeAgent && account.UserType != constants.UserTypeEnterprise {
		return errors.New(errors.CodeForbidden, "无权限操作此账号")
	}

	return s.db.WithContext(ctx).Model(&model.Account{}).
		Where("id = ?", id).
		Updates(map[string]interface{}{
			"status":  status,
			"updater": currentUserID,
		}).Error
}

func getUserTypeName(userType int) string {
	switch userType {
	case constants.UserTypeAgent:
		return "代理账号"
	case constants.UserTypeEnterprise:
		return "企业账号"
	default:
		return "未知"
	}
}

func getStatusName(status int) string {
	if status == constants.StatusEnabled {
		return "启用"
	}
	return "禁用"
}