package services

import (
	"errors"
	"fmt"
	"math/rand"
	"strings"
	"sync"
	"time"

	"server/models"
)

type loginCodeItem struct {
	Code      string
	Channel   string
	ExpiredAt time.Time
}

var loginCodeStore sync.Map

func codeKey(account, channel string) string {
	return strings.ToLower(strings.TrimSpace(account)) + "|" + strings.TrimSpace(channel)
}

func SendPlatformLoginCode(account, channel string) error {
	account = strings.TrimSpace(account)
	channel = strings.TrimSpace(channel)
	if account == "" {
		return errors.New("账号不能为空")
	}
	if channel != "sms" && channel != "email" {
		return errors.New("仅支持短信或邮箱验证码")
	}

	var u models.AdminUser
	if err := models.Orm.QueryTable(new(models.AdminUser)).Filter("account", account).One(&u); err != nil {
		return errors.New("用户不存在")
	}
	if u.Status == 0 {
		return errors.New("账号已禁用")
	}
	if channel == "sms" && (u.Phone == nil || strings.TrimSpace(*u.Phone) == "") {
		return errors.New("该账号未绑定手机号")
	}
	if channel == "email" && (u.Email == nil || strings.TrimSpace(*u.Email) == "") {
		return errors.New("该账号未绑定邮箱")
	}

	rand.Seed(time.Now().UnixNano())
	code := fmt.Sprintf("%06d", rand.Intn(1000000))
	loginCodeStore.Store(codeKey(account, channel), loginCodeItem{
		Code:      code,
		Channel:   channel,
		ExpiredAt: time.Now().Add(5 * time.Minute),
	})
	// TODO: 接入短信/邮箱发送通道。当前阶段只做服务端验证码校验链路。
	return nil
}

func VerifyPlatformLoginCode(account, channel, code string) error {
	account = strings.TrimSpace(account)
	channel = strings.TrimSpace(channel)
	code = strings.TrimSpace(code)
	if account == "" || code == "" {
		return errors.New("验证码不能为空")
	}
	val, ok := loginCodeStore.Load(codeKey(account, channel))
	if !ok {
		return errors.New("验证码不存在或已失效")
	}
	item, ok := val.(loginCodeItem)
	if !ok {
		return errors.New("验证码状态异常")
	}
	if time.Now().After(item.ExpiredAt) {
		loginCodeStore.Delete(codeKey(account, channel))
		return errors.New("验证码已过期")
	}
	if item.Code != code {
		return errors.New("验证码错误")
	}
	loginCodeStore.Delete(codeKey(account, channel))
	return nil
}

func SendBackendLoginCode(tenantName, account, channel string) error {
	tenantName = strings.TrimSpace(tenantName)
	account = strings.TrimSpace(account)
	channel = strings.TrimSpace(channel)
	if tenantName == "" || account == "" {
		return errors.New("租户名称和账号不能为空")
	}
	if channel != "sms" && channel != "email" {
		return errors.New("仅支持短信或邮箱验证码")
	}
	var tenant models.Tenant
	if err := models.Orm.QueryTable(new(models.Tenant)).Filter("tenant_name", tenantName).One(&tenant); err != nil {
		return errors.New("租户不存在")
	}
	var user models.TenantUser
	if err := models.Orm.QueryTable(new(models.TenantUser)).
		Filter("tid", tenant.ID).
		Filter("account", account).
		One(&user); err != nil {
		return errors.New("用户不存在")
	}
	if user.Status == 0 {
		return errors.New("账号已禁用")
	}
	if channel == "sms" && (user.Phone == nil || strings.TrimSpace(*user.Phone) == "") {
		return errors.New("该账号未绑定手机号")
	}
	if channel == "email" && (user.Email == nil || strings.TrimSpace(*user.Email) == "") {
		return errors.New("该账号未绑定邮箱")
	}
	rand.Seed(time.Now().UnixNano())
	code := fmt.Sprintf("%06d", rand.Intn(1000000))
	loginCodeStore.Store(codeKey(tenantName+"#"+account, channel), loginCodeItem{
		Code:      code,
		Channel:   channel,
		ExpiredAt: time.Now().Add(5 * time.Minute),
	})
	return nil
}

func VerifyBackendLoginCode(tenantName, account, channel, code string) error {
	return VerifyPlatformLoginCode(tenantName+"#"+account, channel, code)
}