heimdall

<?php

namespace Galaz\Heimdall;

use Eloquent;
use Session;

class Heimdall extends Eloquent {

    /**
     * Resource ID
     * Categoriy, Users,
     * @var string
     */
    protected static $resourceID;

    /**
     * Errors Array
     *
     * @var array
     */
    protected $errors = array();

    //Requiered Models
    const USER_MODEL = 'Galaz\Heimdall\User';
    const ROLE_MODEL = 'Galaz\Heimdall\Role';
    const PERMISSION_MODEL = 'Galaz\Heimdall\Permission';
    const CATEGORY_MODEL = 'Galaz\Heimdall\Category';

    /**
     * Modes:
     * CAT                  Category
     * SELF                 Ownership required
     * ANY                  All elements
     *
     *
     * Examples:
     * Post @ ANY           Post in Any Category
     * Post @ CAT:News      Post in News Category
     * ALL @ CAT:News       Anything within News Category
     * ALL @ ANY            Everything
     * Category @ ANY
     * Category @ CAT:Users     Categorys within Category 5
     *
     *
     * User @ SELF
     * Content @ ONLY:5,1,15   Content with ids 5 , 1 ,15
     *
     *
     */
    const PERMISSION_SESSION = "PERMISSION_SESSION";
    const PERMISSION_INDEX = "Permissions";
    const ROLE_NAME_INDEX = "Role_Name";
    const ADMIN_OVERRIDE = "ADMIN";
    const CATEGORY_KEY = "CAT";
    const PUBLIC_KEY = "PUBLIC";
    const OWNER_KEY = "SELF";
    const ANY_KEY = "ANY";
    const SPLIT_RESOURCE_MODE = '@';
    const SPLIT_MODE_OPTIONS = ':';
    const SPLIT_OPTIONS = ',';

    public function __construct() {
        //$path = explode('\\', get_class($this));
        self::$resourceID = get_class($this);
        echo self::$resourceID . '<br>';
    }

    public static function RouteFilter(&$route) {

    }

    /**
     *
     * @param string $action
     * @return boolean
     */
    public function MoldelFilter($action) {
        $action = strtoupper($action);
        $continue = in_array($action, array('CREATE', 'READ', 'UPDATE', 'DELETE'));
        if (!$continue) {
            $this->errors['Action'] = "Valid actions are Create, Read, Update and Delete";
            return false;
        }

        if (Session::has(self::PERMISSION_SESSION)) {
            //Variables
            //Get place in session where permitions are stored
            $permit_session = Session::get(self::PERMISSION_SESSION);
            //Get actual permit bag
            $permit_bag = $permit_session[self::PERMISSION_INDEX];

            //actuall filtering...
            //Check is model is un permission array
            if (array_key_exists(self::$resourceID, $permit_bag)) {
                $resource_permissions = $permit_bag[self::$resourceID];
                //Check for permissions, run filters, if one of them passes
                //user have permission to continue
                if (array_key_exists($action, $resource_permissions)) {
                    $permissions = $resource_permissions[$action];
                    return $this->FilterAny($permissions) ||
                            $this->FilterSelf($permissions) ||
                            $this->FilterCategory($permissions) ||
                            $this->FilterPublic($permissions);
                }
            }
            $this->errors['Resource'] = "You don't have access to this Resource";
            return false;
        }
        $this->errors['Session'] = "There's no permission array in session... are you even logged in?";
        return false;
    }

    /**
     *
     * Check if 'ANY' Permission is pressent in the array
     *
     * @param array $resource_permissions
     * @return boolean
     */
    public function FilterAny(&$resource_permissions) {
        if (array_key_exists(self::ANY_KEY, $resource_permissions)) {
            return true;
        } else {
            $this->errors['Any'] = "You don't have global pivileges";
            return false;
        }
    }

    /**
     * Check if User is owner of the resource
     *
     * @param Array $resource_permissions
     * @return boolean
     */
    public function FilterSelf(&$resource_permissions) {
        if (array_key_exists(self::OWNER_KEY, $resource_permissions)) {
            if (method_exists($this, "User")) {
                if ($this->User->id == Auth::user()->id) {
                    return true;
                } else {
                    $this->errors['Self'] = "You are not the owner of this resource";
                    return false;
                }
            } else {
                $this->errors['Self'] = "This resource does not belong to an user";
                return false;
            }
        }
        $this->errors['Self'] = "You have no permission to access this resource";
        return false;
    }

    /**
     *
     * Check if User can access the resource by comparing its category
     *
     * @param Array $resource_permissions
     * @return boolean
     */
    public function FilterCategory(&$resource_permissions) {
        if (array_key_exists(self::CATEGORY_KEY, $resource_permissions)) {
            if (method_exists($this, "Category")) {
                if (in_array($this->Category->id, $resource_permissions[self::CATEGORY_KEY])) {
                    return true;
                } else {
                    $this->errors['Category'] = "You have no permission to access resources in this category";
                    return false;
                }
            } else {
                $this->errors['Category'] = "This resource does not belong to a category";
                return false;
            }
        }
        $this->errors['Category'] = "You have no permission to access this resource";
        return false;
    }

    /**
     * Check if Resource is Public by checking for variable $private
     *
     * @param Array $resource_permissions
     * @return boolean
     */
    public function FilterPublic(&$resource_permissions) {
        if (array_key_exists(self::PUBLIC_KEY, $resource_permissions)) {
            if (isset($this->private)) {
                if ($this->private) {
                    return true;
                } else {
                    $this->errors['Public'] = "This resource is not public, you have no permission to access it";
                    return false;
                }
            } else {
                $this->errors['Public'] = "All Resources Must contain a public field (boolean)";
                return false;
            }
        }
        $this->errors['Public'] = "You have no permission to access this resource";
        return false;
    }

    public function getErrors() {
        return $this->errors;
    }

}