package logic

import (
	"context"
	"errors"
	"time"

	tokenx "bj_power_mes/common/token"
	"bj_power_mes/ent"
	"bj_power_mes/ent/permission"
	"bj_power_mes/ent/role"
	"bj_power_mes/ent/user"
	"bj_power_mes/ent/userstation"

	"golang.org/x/crypto/bcrypt"
)

// ------ 请求/返回 DTO ------

type LoginReq struct {
	Username string `json:"username"`
	Password string `json:"password"`
}

type LoginResp struct {
	AccessToken  string `json:"accessToken"`
	RefreshToken string `json:"refreshToken"`
	AccessExpire int64  `json:"accessExpire"`
}

type RefreshReq struct {
	RefreshToken string `json:"refreshToken"`
}

type UserInfoResp struct {
	UserId          int              `json:"userId"`
	Username        string           `json:"username"`
	Name            string           `json:"name"`
	RoleId          int              `json:"roleId"`
	RoleCode        string           `json:"roleCode"`
	RoleName        string           `json:"roleName"`
	Menus           []permissionItem `json:"menus"`
	PermissionCodes []string         `json:"permissionCodes"`
}

type ChangePasswordReq struct {
	OldPassword string `json:"oldPassword"`
	NewPassword string `json:"newPassword"`
}

type permissionItem struct {
	Code string `json:"code"`
	Name string `json:"name"`
	Path string `json:"path"`
	Icon string `json:"icon"`
}

// currentToken 生成 access + refresh 双 token
func (s *Service) issueTokens(usr *ent.User, roleEntity *ent.Role) (LoginResp, error) {
	claims := tokenx.Claims{UserId: usr.ID, Username: usr.Username, Name: usr.Name, RoleId: usr.RoleId}
	if roleEntity != nil {
		claims.RoleCode = roleEntity.Code
		claims.RoleName = roleEntity.Name
	} else {
		claims.RoleCode = ""
		claims.RoleName = ""
	}
	access, err := tokenx.Issue(s.ctx.Config.Auth.AccessSecret, time.Duration(s.ctx.Config.Auth.AccessExpire)*time.Second, claims)
	if err != nil {
		return LoginResp{}, err
	}
	refresh, err := tokenx.Issue(s.ctx.Config.Auth.AccessSecret, time.Duration(s.ctx.Config.Auth.RefreshExpire)*time.Second, claims)
	if err != nil {
		return LoginResp{}, err
	}
	return LoginResp{AccessToken: access, RefreshToken: refresh, AccessExpire: s.ctx.Config.Auth.AccessExpire}, nil
}

// Login 登录
func (s *Service) Login(ctx context.Context, req LoginReq) (LoginResp, error) {
	var resp LoginResp
	usr, err := s.ctx.EntClient.User.Query().Where(user.Username(req.Username)).First(ctx)
	if err != nil {
		return resp, errors.New("用户名或密码错误")
	}
	if usr.Status != "ENABLED" {
		return resp, errors.New("账号已禁用")
	}
	if bcrypt.CompareHashAndPassword([]byte(usr.Password), []byte(req.Password)) != nil {
		return resp, errors.New("用户名或密码错误")
	}
	roleEntity, _ := s.ctx.EntClient.Role.Get(ctx, usr.RoleId)
	return s.issueTokens(usr, roleEntity)
}

// Refresh 刷新访问令牌（滑动续签）
func (s *Service) Refresh(ctx context.Context, req RefreshReq) (LoginResp, error) {
	var resp LoginResp
	claims, err := tokenx.Parse(s.ctx.Config.Auth.AccessSecret, req.RefreshToken)
	if err != nil {
		return resp, errors.New("刷新令牌无效或已过期")
	}
	usr, err := s.ctx.EntClient.User.Get(ctx, claims.UserId)
	if err != nil {
		return resp, errors.New("用户不存在")
	}
	if usr.Status != "ENABLED" {
		return resp, errors.New("账号已禁用")
	}
	roleEntity, _ := s.ctx.EntClient.Role.Get(ctx, usr.RoleId)
	return s.issueTokens(usr, roleEntity)
}

// UserInfo 当前用户信息 + 菜单权限
func (s *Service) UserInfo(ctx context.Context, userId int) (UserInfoResp, error) {
	var out UserInfoResp
	usr, err := s.ctx.EntClient.User.Get(ctx, userId)
	if err != nil {
		return out, err
	}
	out.UserId = usr.ID
	out.Username = usr.Username
	out.Name = usr.Name
	out.RoleId = usr.RoleId

	roleEntity, err := s.ctx.EntClient.Role.Get(ctx, usr.RoleId)
	if err != nil {
		roleEntity = nil
	}
	if roleEntity != nil {
		out.RoleCode = roleEntity.Code
		out.RoleName = roleEntity.Name
		out.PermissionCodes = roleEntity.PermissionCodes
	}
	// 取所拥有权限对应的菜单
	perms, err := s.ctx.EntClient.Permission.Query().
		Where(permission.Type("MENU")).
		Order(ent.Asc(permission.FieldSort)).All(ctx)
	if err != nil {
		return out, nil
	}
	owned := map[string]bool{}
	for _, c := range out.PermissionCodes {
		owned[c] = true
	}
	for _, p := range perms {
		if roleEntity == nil {
			continue
		}
		if roleEntity.Code == "SUPER_ADMIN" || owned[p.Code] || owned["*"] {
			out.Menus = append(out.Menus, permissionItem{Code: p.Code, Name: p.Name, Path: p.Path, Icon: p.Icon})
		}
	}
	return out, nil
}

// ChangePassword 当前登录用户修改自己的密码
func (s *Service) ChangePassword(ctx context.Context, userId int, req ChangePasswordReq) error {
	if userId <= 0 {
		return errors.New("未登录")
	}
	if req.OldPassword == "" || req.NewPassword == "" {
		return errors.New("请输入旧密码与新密码")
	}
	if len(req.NewPassword) < 6 {
		return errors.New("新密码长度至少 6 位")
	}
	if err := checkPasswordStrong(req.NewPassword); err != nil {
		return err
	}
	usr, err := s.ctx.EntClient.User.Get(ctx, userId)
	if err != nil {
		return errors.New("用户不存在")
	}
	if bcrypt.CompareHashAndPassword([]byte(usr.Password), []byte(req.OldPassword)) != nil {
		return errors.New("旧密码不正确")
	}
	hash, err := bcrypt.GenerateFromPassword([]byte(req.NewPassword), bcrypt.DefaultCost)
	if err != nil {
		return err
	}
	return s.ctx.EntClient.User.UpdateOneID(userId).SetPassword(string(hash)).Exec(ctx)
}

// ------ 工位终端登录（块1：用户体系来源于 MES，终端登录改调本接口） ------

type StationLoginReq struct {
	Username  string `json:"username"`
	Password  string `json:"password"`
	StationNo int    `json:"stationNo"`
}

type StationLoginResp struct {
	AccessToken string       `json:"accessToken"`
	ExpireAt    int64        `json:"expireAt"`
	User        UserInfoResp `json:"user"`
	Stations    []int        `json:"stations"`
	StationNo   int          `json:"stationNo"`
}

// StationLogin 工位终端登录：校验 用户名 + 工位终端密码 + 工位权限
func (s *Service) StationLogin(ctx context.Context, req StationLoginReq) (StationLoginResp, error) {
	var resp StationLoginResp
	if req.Username == "" || req.Password == "" {
		return resp, errors.New("用户名和密码必填")
	}
	usr, err := s.ctx.EntClient.User.Query().Where(user.Username(req.Username)).First(ctx)
	if err != nil {
		return resp, errors.New("用户名或密码错误")
	}
	if usr.Status != "ENABLED" {
		return resp, errors.New("账号已禁用")
	}
	if !usr.CanLoginWorkstation {
		return resp, errors.New("该账号未开通工位终端登录权限")
	}
	if usr.WorkstationPassword == "" || bcrypt.CompareHashAndPassword([]byte(usr.WorkstationPassword), []byte(req.Password)) != nil {
		return resp, errors.New("用户名或密码错误")
	}
	stations := s.UserStations(ctx, usr.ID)
	if len(stations) == 0 {
		for i := 1; i <= 12; i++ {
			stations = append(stations, i)
		}
	}
	if req.StationNo > 0 {
		allowed := false
		for _, no := range stations {
			if no == req.StationNo {
				allowed = true
				break
			}
		}
		if !allowed {
			return resp, errors.New("该账号无此工位的操作权限")
		}
	}
	roleEntity, _ := s.ctx.EntClient.Role.Get(ctx, usr.RoleId)
	claims := tokenx.Claims{UserId: usr.ID, Username: usr.Username, Name: usr.Name, RoleId: usr.RoleId, StationNo: req.StationNo}
	if roleEntity != nil {
		claims.RoleCode = roleEntity.Code
		claims.RoleName = roleEntity.Name
	}
	access, err := tokenx.Issue(s.ctx.Config.Auth.AccessSecret, time.Duration(s.ctx.Config.Auth.AccessExpire)*time.Second, claims)
	if err != nil {
		return resp, err
	}
	resp.AccessToken = access
	resp.ExpireAt = time.Now().Add(time.Duration(s.ctx.Config.Auth.AccessExpire) * time.Second).Unix()
	resp.User = UserInfoResp{UserId: usr.ID, Username: usr.Username, Name: usr.Name, RoleId: usr.RoleId}
	if roleEntity != nil {
		resp.User.RoleCode = roleEntity.Code
		resp.User.RoleName = roleEntity.Name
	}
	resp.Stations = stations
	resp.StationNo = req.StationNo
	return resp, nil
}

// StationChangePassword 工位终端修改自己的工位终端密码
func (s *Service) StationChangePassword(ctx context.Context, userId int, oldPwd, newPwd string) error {
	if userId <= 0 {
		return errors.New("未登录")
	}
	if oldPwd == "" || newPwd == "" {
		return errors.New("请输入原密码与新密码")
	}
	if err := checkPasswordStrong(newPwd); err != nil {
		return err
	}
	usr, err := s.ctx.EntClient.User.Get(ctx, userId)
	if err != nil {
		return errors.New("用户不存在")
	}
	if !usr.CanLoginWorkstation {
		return errors.New("该账号未开通工位终端登录权限")
	}
	if bcrypt.CompareHashAndPassword([]byte(usr.WorkstationPassword), []byte(oldPwd)) != nil {
		return errors.New("原工位终端密码不正确")
	}
	hash, _ := bcrypt.GenerateFromPassword([]byte(newPwd), bcrypt.DefaultCost)
	return s.ctx.EntClient.User.UpdateOneID(userId).SetWorkstationPassword(string(hash)).Exec(ctx)
}

// ------ 用户 / 角色 / 权限 管理 ------

type UserReq struct {
	Id                  int    `json:"id"`
	Username            string `json:"username"`
	Password            string `json:"password"`
	Name                string `json:"name"`
	RoleId              int    `json:"roleId"`
	Status              string `json:"status"`
	CanLoginWorkstation bool   `json:"canLoginWorkstation"`
	WorkstationPassword string `json:"workstationPassword"`
	Stations            []int  `json:"stations"` // 允许操作的工位号列表
}

// checkPasswordStrong 校验密码：长度>=6 且不能是纯数字
func checkPasswordStrong(pwd string) error {
	if len(pwd) < 6 {
		return errors.New("密码长度至少 6 位")
	}
	allDigit := true
	for _, r := range pwd {
		if r < '0' || r > '9' {
			allDigit = false
			break
		}
	}
	if allDigit {
		return errors.New("密码不能是纯数字")
	}
	return nil
}

func (s *Service) CreateUser(ctx context.Context, req UserReq) error {
	if err := checkPasswordStrong(req.Password); err != nil {
		return err
	}
	hash, err := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
	if err != nil {
		return err
	}
	status := req.Status
	if status == "" {
		status = "ENABLED"
	}
	create := s.ctx.EntClient.User.Create().
		SetUsername(req.Username).
		SetPassword(string(hash)).
		SetName(req.Name).
		SetRoleId(req.RoleId).
		SetStatus(status).
		SetCanLoginWorkstation(req.CanLoginWorkstation)
	if req.CanLoginWorkstation {
		wsPwd := req.WorkstationPassword
		if wsPwd == "" {
			wsPwd = req.Password // 默认复用登录密码
		}
		if err := checkPasswordStrong(wsPwd); err != nil {
			return errors.New("工位终端密码" + err.Error())
		}
		wsHash, err := bcrypt.GenerateFromPassword([]byte(wsPwd), bcrypt.DefaultCost)
		if err != nil {
			return err
		}
		create.SetWorkstationPassword(string(wsHash))
	}
	usr, err := create.Save(ctx)
	if err != nil {
		return err
	}
	return s.replaceUserStations(ctx, usr.ID, req.Stations)
}

func (s *Service) UpdateUser(ctx context.Context, req UserReq) error {
	u := s.ctx.EntClient.User.UpdateOneID(req.Id).SetRoleId(req.RoleId).SetName(req.Name).
		SetCanLoginWorkstation(req.CanLoginWorkstation)
	if req.Password != "" {
		if err := checkPasswordStrong(req.Password); err != nil {
			return err
		}
		hash, _ := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
		u.SetPassword(string(hash))
	}
	if req.CanLoginWorkstation {
		if req.WorkstationPassword != "" {
			if err := checkPasswordStrong(req.WorkstationPassword); err != nil {
				return errors.New("工位终端密码" + err.Error())
			}
			wsHash, _ := bcrypt.GenerateFromPassword([]byte(req.WorkstationPassword), bcrypt.DefaultCost)
			u.SetWorkstationPassword(string(wsHash))
		}
	} else {
		u.SetWorkstationPassword("")
	}
	if req.Status != "" {
		u.SetStatus(req.Status)
	}
	if err := u.Exec(ctx); err != nil {
		return err
	}
	return s.replaceUserStations(ctx, req.Id, req.Stations)
}

// replaceUserStations 全量替换用户-工位关联
func (s *Service) replaceUserStations(ctx context.Context, userId int, stations []int) error {
	if _, err := s.ctx.EntClient.UserStation.Delete().Where(userstation.UserId(userId)).Exec(ctx); err != nil {
		return err
	}
	for _, no := range stations {
		if no <= 0 {
			continue
		}
		if err := s.ctx.EntClient.UserStation.Create().
			SetUserId(userId).SetStationNo(no).Exec(ctx); err != nil {
			return err
		}
	}
	return nil
}

// UserStations 查询用户绑定的工位号
func (s *Service) UserStations(ctx context.Context, userId int) []int {
	rows, _ := s.ctx.EntClient.UserStation.Query().
		Where(userstation.UserId(userId)).All(ctx)
	out := make([]int, 0, len(rows))
	for _, r := range rows {
		out = append(out, r.StationNo)
	}
	return out
}

func (s *Service) DeleteUser(ctx context.Context, id int) error {
	if id == 1 {
		return errors.New("不能删除超级管理员")
	}
	return s.ctx.EntClient.User.DeleteOneID(id).Exec(ctx)
}

// UserVO 用户列表返回体（含工位终端属性与允许操作工位）
type UserVO struct {
	Id                  int    `json:"id"`
	Username            string `json:"username"`
	Name                string `json:"name"`
	RoleId              int    `json:"roleId"`
	Status              string `json:"status"`
	CanLoginWorkstation bool   `json:"canLoginWorkstation"`
	Stations            []int  `json:"stations"` // 允许登录/操作的工位号（空=全部工位）
}

func (s *Service) ListUsers(ctx context.Context) ([]UserVO, error) {
	usrs, err := s.ctx.EntClient.User.Query().Order(ent.Asc(user.FieldID)).All(ctx)
	if err != nil {
		return nil, err
	}
	out := make([]UserVO, 0, len(usrs))
	for _, u := range usrs {
		out = append(out, UserVO{
			Id:                  u.ID,
			Username:            u.Username,
			Name:                u.Name,
			RoleId:              u.RoleId,
			Status:              u.Status,
			CanLoginWorkstation: u.CanLoginWorkstation,
			Stations:            s.UserStations(ctx, u.ID),
		})
	}
	return out, nil
}

type RoleReq struct {
	Id              int      `json:"id"`
	Name            string   `json:"name"`
	Code            string   `json:"code"`
	Remark          string   `json:"remark"`
	PermissionCodes []string `json:"permissionCodes"`
}

func (s *Service) CreateRole(ctx context.Context, req RoleReq) error {
	return s.ctx.EntClient.Role.Create().
		SetName(req.Name).SetCode(req.Code).SetRemark(req.Remark).
		SetPermissionCodes(req.PermissionCodes).Exec(ctx)
}

func (s *Service) UpdateRole(ctx context.Context, req RoleReq) error {
	return s.ctx.EntClient.Role.UpdateOneID(req.Id).
		SetName(req.Name).SetCode(req.Code).SetRemark(req.Remark).
		SetPermissionCodes(req.PermissionCodes).Exec(ctx)
}

func (s *Service) DeleteRole(ctx context.Context, id int) error {
	// 保护：不可删除超级管理员角色
	r, err := s.ctx.EntClient.Role.Get(ctx, id)
	if err != nil {
		return errors.New("角色不存在")
	}
	if r.Code == "SUPER_ADMIN" {
		return errors.New("超级管理员角色不允许删除")
	}
	// 保护：仍有关联用户的角色不可删除（避免产生无主用户/失去全部管理员）
	cnt, err := s.ctx.EntClient.User.Query().
		Where(user.RoleId(id)).Count(ctx)
	if err == nil && cnt > 0 {
		return errors.New("该角色下仍有用户，请先移除相关用户")
	}
	return s.ctx.EntClient.Role.DeleteOneID(id).Exec(ctx)
}

func (s *Service) ListRoles(ctx context.Context) ([]*ent.Role, error) {
	return s.ctx.EntClient.Role.Query().Order(ent.Asc(role.FieldID)).All(ctx)
}

type PermissionReq struct {
	Id     int    `json:"id"`
	Code   string `json:"code"`
	Name   string `json:"name"`
	Type   string `json:"type"`
	Path   string `json:"path"`
	Icon   string `json:"icon"`
	Sort   int    `json:"sort"`
	Remark string `json:"remark"`
}

func (s *Service) CreatePermission(ctx context.Context, req PermissionReq) error {
	return s.ctx.EntClient.Permission.Create().
		SetCode(req.Code).SetName(req.Name).SetType(req.Type).
		SetPath(req.Path).SetIcon(req.Icon).SetSort(req.Sort).SetRemark(req.Remark).Exec(ctx)
}

func (s *Service) UpdatePermission(ctx context.Context, req PermissionReq) error {
	return s.ctx.EntClient.Permission.UpdateOneID(req.Id).
		SetCode(req.Code).SetName(req.Name).SetType(req.Type).
		SetPath(req.Path).SetIcon(req.Icon).SetSort(req.Sort).SetRemark(req.Remark).Exec(ctx)
}

func (s *Service) DeletePermission(ctx context.Context, id int) error {
	return s.ctx.EntClient.Permission.DeleteOneID(id).Exec(ctx)
}

func (s *Service) ListPermissions(ctx context.Context) ([]*ent.Permission, error) {
	return s.ctx.EntClient.Permission.Query().Order(ent.Asc(permission.FieldSort), ent.Asc(permission.FieldID)).All(ctx)
}