package auth

import (
	"context"
	"crypto/rand"
	"fmt"
	"math/big"
	"time"

	"haixun-backend/internal/library/clock"
	"haixun-backend/internal/logic/authz"
	memberusecase "haixun-backend/internal/model/member/domain/usecase"
	"haixun-backend/internal/svc"
	"haixun-backend/internal/types"

	"github.com/zeromicro/go-zero/core/logx"
)

type RegisterLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

func NewRegisterLogic(ctx context.Context, svcCtx *svc.ServiceContext) *RegisterLogic {
	return &RegisterLogic{ctx: ctx, svcCtx: svcCtx}
}

func (l *RegisterLogic) Register(req *types.AuthRegisterReq) (*types.AuthTokenData, error) {
	if err := authz.RequireAdmin(l.ctx, l.svcCtx); err != nil {
		return nil, err
	}
	member, token, err := l.svcCtx.Member.Register(l.ctx, memberusecase.RegisterRequest{
		TenantID:    req.TenantID,
		Email:       req.Email,
		Password:    req.Password,
		DisplayName: req.DisplayName,
		Language:    req.Language,
	})
	if err != nil {
		return nil, err
	}
	verifyCode, err := newVerifyCode()
	if err != nil {
		return nil, err
	}
	expiresAt := clock.NowUnixNano() + int64(15*time.Minute)
	if err := l.svcCtx.Member.SetEmailVerificationCode(l.ctx, member.TenantID, member.UID, verifyCode, expiresAt); err != nil {
		return nil, err
	}
	if l.svcCtx.Mailer != nil {
		body := fmt.Sprintf("你的巡樓 Console 驗證碼是：%s\n\n此驗證碼 15 分鐘內有效。", verifyCode)
		if err := l.svcCtx.Mailer.Send(l.ctx, member.Email, "巡樓 Console 帳號驗證碼", body); err != nil {
			logx.WithContext(l.ctx).Errorf("send verification email failed: uid=%s err=%v", member.UID, err)
		}
	}
	return toAuthTokenData(token), nil
}

func newVerifyCode() (string, error) {
	n, err := rand.Int(rand.Reader, big.NewInt(1000000))
	if err != nil {
		return "", err
	}
	return fmt.Sprintf("%06d", n.Int64()), nil
}