package service

import (
	"context"

	"git.nobla.cn/golang/aeus-admin/models"
	"git.nobla.cn/golang/aeus-admin/pb"
	"git.nobla.cn/golang/aeus-admin/types"
	"git.nobla.cn/golang/aeus/middleware/auth"
	"git.nobla.cn/golang/aeus/pkg/errors"
	"gorm.io/gorm"
)

type (
	menuOptions struct {
		db *gorm.DB
	}
	MenuOption func(o *menuOptions)

	MenuService struct {
		opts *menuOptions
	}
)

func WithMenuDB(db *gorm.DB) MenuOption {
	return func(o *menuOptions) {
		o.db = db
	}
}

func (s *MenuService) hasPermission(menuID int64, permissions []*models.Permission) bool {
	for _, permission := range permissions {
		if permission.MenuId == menuID {
			return true
		}
	}
	return false
}

func (s *MenuService) getPermissions(menuID int64, permissions []*models.Permission) []*pb.PermissionItem {
	ss := make([]*pb.PermissionItem, 0, 10)
	for _, permission := range permissions {
		if permission.MenuId == menuID {
			ss = append(ss, &pb.PermissionItem{
				Value: permission.Permission,
				Label: permission.Label,
			})
		}
	}
	return ss
}

func (s *MenuService) recursiveNestedMenu(ctx context.Context, parent int64, perm bool, menus []*models.Menu, permissions []*models.Permission) []*pb.MenuItem {
	values := make([]*pb.MenuItem, 0)
	for _, row := range menus {
		if row.ParentId == parent {
			if !row.Public && !s.hasPermission(row.Id, permissions) {
				continue
			}
			v := &pb.MenuItem{
				Label:    row.Label,
				Name:     row.Name,
				Icon:     row.Icon,
				Hidden:   row.Hidden,
				Route:    row.Uri,
				Children: s.recursiveNestedMenu(ctx, row.Id, perm, menus, permissions),
			}
			if perm {
				v.Permissions = s.getPermissions(row.Id, permissions)
			}
			values = append(values, v)
		}
	}
	return values
}

func (s *MenuService) GetRolePermissions(ctx context.Context, db *gorm.DB, role string) (permissions []*models.Permission, err error) {
	permissions = make([]*models.Permission, 0)
	err = db.Where("id IN (SELECT permission_id FROM role_permissions WHERE role = ?)", role).Find(&permissions).Error
	return
}

func (s *MenuService) GetMenus(ctx context.Context, req *pb.GetMenuRequest) (res *pb.GetMenuResponse, err error) {
	claims, ok := auth.FromContext(ctx)
	if !ok {
		return nil, errors.ErrAccessDenied
	}
	var (
		permissions []*models.Permission
	)
	tx := s.opts.db.WithContext(ctx)
	if claims, ok := claims.(*types.Claims); ok {
		permissions, err = s.GetRolePermissions(ctx, tx, claims.Role)
	}
	values := make([]*models.Menu, 0)
	if err = tx.Find(&values).Error; err != nil {
		return
	}
	res = &pb.GetMenuResponse{
		Data: s.recursiveNestedMenu(ctx, 0, req.Permission, values, permissions),
	}
	return
}

func NewMenuService(cbs ...MenuOption) *MenuService {
	opts := &menuOptions{}
	for _, cb := range cbs {
		cb(opts)
	}
	return &MenuService{
		opts: opts,
	}
}