package service

import (
	"context"
	"crypto/sha256"
	"encoding/hex"
	"errors"
	"github.com/google/uuid"
	"github.com/labstack/echo/v4"
	"golang.org/x/time/rate"
	"mylomen_server/common/constant"
	"mylomen_server/common/dto"
	"mylomen_server/common/email"
	"mylomen_server/common/logs"
	"mylomen_server/common/utils"
	"mylomen_server/common/xjwt"
	"mylomen_server/infrastructure/convert"
	"mylomen_server/infrastructure/redis"
	"mylomen_server/infrastructure/repository"
	"strings"
	"time"
)

type user struct {
}

var UserBiz user

// 令牌桶大小为 100, 以每秒 10 个 Token 的速率向桶中放置 Token
var limiter = rate.NewLimiter(10, 10)

// Register 注册
func (l user) Register(ctx context.Context, req dto.RegisterReq) error {
	acUser := repository.GUser.FindByReq(ctx, req.LoginReq)
	if acUser != nil && acUser.Deleted == false {
		return errors.New("user exist")
	}

	//fill data
	userDO := convert.UserReq2DO(req)
	userDO.Deleted = false
	userDO.UpdateTime = time.Now()
	userDO.NickName = req.NickName
	userDO.Avatar = req.Avatar

	//密码加密
	h := sha256.Sum256([]byte(req.Password))
	passHash := hex.EncodeToString(h[:])
	userDO.Pwd = &passHash

	return repository.GUser.Create(ctx, &userDO)
}

func (l user) Login(ctx context.Context, req dto.LoginReq) (*dto.UserVO, error) {
	start := time.Now().UnixMilli()

	//1. 查询用户
	acUser := repository.GUser.FindByReq(ctx, req)
	if acUser == nil || acUser.Deleted == true {
		return nil, errors.New("user not exist")
	}

	//2. email 和 手机号登录 和account 需要验证密码。其他情况不需要验证密码
	if req.Account != nil || req.Email != nil || req.Phone != nil {
		if acUser.Pwd == nil {
			return nil, errors.New("password not set")
		}
		// 验证账号密码
		h := sha256.Sum256([]byte(req.Password))
		passHash := hex.EncodeToString(h[:])
		if acUser.Pwd == nil || passHash != *acUser.Pwd {
			return nil, errors.New("password is error")
		}
	}

	//3. 组装数据
	result := convert.UserDO2VO(*acUser)
	result.Platform = req.Platform

	//生成token
	token := strings.ReplaceAll(uuid.New().String(), "-", "")
	claims := dto.LoginTokenVo{Sn: result.Sn, Token: token}
	//设置超时时间
	claims.SetExtByPlatform(req.Platform)
	result.Token = xjwt.GenJwtToken(claims)
	diff := time.Now().UnixMilli() - start
	logs.NewLog("").Infof("Login cost: %d", diff)
	return &result, nil
}

func (l user) SendResetPwdCode(ctx context.Context, emailP string) error {
	//1. 验证账号
	acUser := repository.GUser.FindByEmail(ctx, emailP)
	if acUser == nil || acUser.Deleted == true {
		return errors.New("user not exist")
	}

	//2. 生成code & 发送
	code := utils.GetPseudoRandomCode(6)

	//3. save into redis
	if err := redis.Set(constant.G_RESET_PWD_CODE+emailP, code, time.Duration(30)*time.Minute); err != nil {
		return errors.New("cache illegal")
	}

	//频控
	if !limiter.Allow() {
		return errors.New("rate limit, please try again later")
	}

	//4. send code
	if err := email.SendEmailVerifyCodeByEmail(code, emailP); err != nil {
		return errors.New("send email code illegal")
	}

	return nil
}

// ResetPwd 重置密码
func (l user) ResetPwd(ctx context.Context, req dto.ResetPwdReq) error {
	//1. 验证code
	redisStr, err := redis.Get(constant.G_RESET_PWD_CODE + req.Account)
	if err != nil && redisStr != req.Code {
		return errors.New("code is error")
	}

	//2. 查询用户
	acUser := repository.GUser.FindByAccount(ctx, req.Account)
	if acUser == nil || acUser.Deleted == true {
		return errors.New("user not exist")
	}

	//3. 重置密码
	h := sha256.Sum256([]byte(req.Password))
	passHash := hex.EncodeToString(h[:])
	acUser.Pwd = &passHash
	if updateErr := repository.GUser.UpdateById(ctx, acUser); updateErr != nil {
		logs.NewLog("").Errorf("update user password req:%+v error: %+v", req, updateErr)
		return errors.New("system error")
	}

	return nil
}

func (l user) GetLoginResult(ctx context.Context, c *echo.Context) (*dto.UserVO, error) {
	accessToken := utils.GetAccessToken(c)
	loginVo, err := xjwt.ParseJwtToken(accessToken)
	if err != nil || loginVo.Sn == "" {
		return nil, errors.New("token illegal")
	}

	//查询数据库
	userDO := repository.GUser.FindBySn(ctx, loginVo.Sn)
	if err != nil || userDO == nil {
		return nil, errors.New("user not exist")
	}

	result := convert.UserDO2VO(*userDO)
	result.Token = accessToken
	result.Platform = loginVo.Platform
	return utils.ToPtr(result), nil
}