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"

	"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 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
}

// ------ 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"`
}

func (s *Service) CreateUser(ctx context.Context, req UserReq) error {
	hash, err := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
	if err != nil {
		return err
	}
	status := req.Status
	if status == "" {
		status = "ENABLED"
	}
	return s.ctx.EntClient.User.Create().
		SetUsername(req.Username).
		SetPassword(string(hash)).
		SetName(req.Name).
		SetRoleId(req.RoleId).
		SetStatus(status).
		Exec(ctx)
}

func (s *Service) UpdateUser(ctx context.Context, req UserReq) error {
	u := s.ctx.EntClient.User.UpdateOneID(req.Id).SetRoleId(req.RoleId).SetName(req.Name)
	if req.Password != "" {
		hash, _ := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
		u.SetPassword(string(hash))
	}
	if req.Status != "" {
		u.SetStatus(req.Status)
	}
	return u.Exec(ctx)
}

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)
}

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

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 {
	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)
}