<?php
/************************************************************************
 * This file is part of EspoCRM.
 *
 * EspoCRM - Open Source CRM application.
 * Copyright (C) 2014-2015 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
 * Website: http://www.espocrm.com
 *
 * EspoCRM is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * EspoCRM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
 ************************************************************************/

namespace Espo\Core;

use \Espo\Core\Exceptions\Error;

use \Espo\ORM\Entity;

class Acl
{
    private $data = array();

    private $cacheFile;

    private $actionList = array('read', 'edit', 'delete');

    private $levelList = array('all', 'team', 'own', 'no');

    protected $fileManager;

    protected $metadata;

    public function __construct(\Espo\Entities\User $user, $config = null, $fileManager = null, $metadata = null)
    {
        $this->user = $user;

        $this->metadata = $metadata;

        if (!$this->user->isFetched()) {
            throw new Error();
        }

        $this->user->loadLinkMultipleField('teams');

        if ($fileManager) {
            $this->fileManager = $fileManager;
        }

        $this->cacheFile = 'data/cache/application/acl/' . $user->id . '.php';

        if ($config && $config->get('useCache') && file_exists($this->cacheFile)) {
            $cached = include $this->cacheFile;
            $this->data = $cached;
            $this->initSolid();
        } else {
            $this->load();
            $this->initSolid();
            if ($config && $fileManager && $config->get('useCache')) {
                $this->buildCache();
            }
        }

    }

    public function checkScope($scope, $action = null, $isOwner = null, $inTeam = null, $entity = null)
    {
        if (array_key_exists($scope, $this->data)) {
            if ($this->data[$scope] === false) {
                return false;
            }
            if ($this->data[$scope] === true) {
                return true;
            }
            if (!is_null($action)) {
                if (array_key_exists($action, $this->data[$scope])) {
                    $value = $this->data[$scope][$action];

                    if ($value === 'all' || $value === true) {
                        return true;
                    }

                    if (!$value || $value === 'no') {
                        return false;
                    }

                    if (is_null($isOwner)) {
                        return true;
                    }

                    if ($isOwner) {
                        if ($value === 'own' || $value === 'team') {
                            return true;
                        }
                    }
                    if ($inTeam === null && $entity) {
                        $inTeam = $this->checkInTeam($entity);
                    }

                    if ($inTeam) {
                        if ($value === 'team') {
                            return true;
                        }
                    }

                    return false;
                }
            }
            return true;
        }
        return true;
    }

    public function toArray()
    {
        return $this->data;
    }

    public function getLevel($scope, $action)
    {
        if ($this->user->isAdmin()) {
            return 'all';
        }
        if (array_key_exists($scope, $this->data)) {
            if (array_key_exists($action, $this->data[$scope])) {
                return $this->data[$scope][$action];
            }
        }
        return false;
    }

    public function check($subject, $action = null, $isOwner = null, $inTeam = null)
    {
        if ($this->user->isAdmin()) {
            return true;
        }
        if (is_string($subject)) {
            return $this->checkScope($subject, $action, $isOwner, $inTeam);
        } else {
            $entity = $subject;
            if ($entity instanceof Entity) {
                $entityName = $entity->getEntityName();
                return $this->checkScope($entityName, $action, $this->checkIsOwner($entity), $inTeam, $entity);
            }
        }
    }

    public function checkReadOnlyTeam($scope)
    {
        if (isset($this->data[$scope]) && isset($this->data[$scope]['read'])) {
            return $this->data[$scope]['read'] === 'team';
        }
        return false;
    }

    public function checkReadOnlyOwn($scope)
    {
        if ($this->user->isAdmin()) {
            return false;
        }
        if (isset($this->data[$scope]) && isset($this->data[$scope]['read'])) {
            return $this->data[$scope]['read'] === 'own';
        }
        return false;
    }

    public function checkIsOwner($entity)
    {
        if ($this->user->isAdmin()) {
            return false;
        }
        $userId = $this->user->id;
        if ($userId === $entity->get('assignedUserId') || $userId === $entity->get('createdById')) {
            return true;
        }
        return false;
    }

    public function checkInTeam($entity)
    {
        $userTeamIds = $this->user->get('teamsIds');

        if (!$entity->hasRelation('teams') || !$entity->hasField('teamsIds')) {
            return false;
        }

        if (!$entity->has('teamsIds')) {
            $entity->loadLinkMultipleField('teams');
        }

        $teamIds = $entity->get('teamsIds');

        if (empty($teamIds)) {
            return false;
        }

        foreach ($userTeamIds as $id) {
            if (in_array($id, $teamIds)) {
                return true;
            }
        }
        return false;
    }

    private function load()
    {
        $aclTables = array();

        $userRoles = $this->user->get('roles');

        foreach ($userRoles as $role) {
            $aclTables[] = $role->get('data');
        }

        $teams = $this->user->get('teams');
        foreach ($teams as $team) {
            $teamRoles = $team->get('roles');
            foreach ($teamRoles as $role) {
                $aclTables[] = $role->get('data');
            }
        }

        $this->data = $this->merge($aclTables);
    }

    private function initSolid()
    {
        $data = $this->metadata->get('app.acl.solid', array());

        foreach ($data as $entityName => $item) {
            $this->data[$entityName] = $item;
        }
    }

    private function merge($tables)
    {
        $data = array();
        foreach ($tables as $table) {
            foreach ($table as $scope => $row) {
                if ($row == false) {
                    if (!isset($data[$scope])) {
                        $data[$scope] = false;
                    }
                } else {
                    if (!isset($data[$scope])) {
                        $data[$scope] = array();
                    }
                    if ($data[$scope] == false) {
                        $data[$scope] = array();
                    }
                    foreach ($row as $action => $level) {
                        if (!isset($data[$scope][$action])) {
                            $data[$scope][$action] = $level;
                        } else {
                            if (array_search($data[$scope][$action], $this->levelList) > array_search($level, $this->levelList)) {
                                $data[$scope][$action] = $level;
                            }
                        }
                    }
                }
            }
        }
        return $data;
    }

    private function buildCache()
    {
        $contents = '<' . '?'. 'php return ' .  var_export($this->data, true)  . ';';
        $this->fileManager->putContents($this->cacheFile, $contents);
    }
}