/**
* Loads the post referenced by $postId. Returns null when:
* $postId does not belong to the workflow
* The user does not have view access to the topic title
* The user does not have view access to the referenced post
* All these conditions add a relevant error message to $this->errors when returning null
*
* @param UUID|string $postId The post being requested
* @return PostRevision|null
*/
protected function loadRequestedPost($postId)
{
if (!$postId instanceof UUID) {
$postId = UUID::create($postId);
}
if ($this->rootLoader === null) {
// Since there is no root loader the full tree is already loaded
$topicTitle = $root = $this->loadRootPost();
if (!$topicTitle) {
return null;
}
$post = $root->getDescendant($postId);
if ($post === null) {
// The requested postId is not a member of the current workflow
$this->addError('post', $this->context->msg('flow-error-invalid-postId', $postId->getAlphadecimal()));
return null;
}
} else {
// Load the post and its root
$found = $this->rootLoader->getWithRoot($postId);
if (!$found['post'] || !$found['root'] || !$found['root']->getPostId()->equals($this->workflow->getId())) {
$this->addError('post', $this->context->msg('flow-error-invalid-postId', $postId->getAlphadecimal()));
return null;
}
$this->topicTitle = $topicTitle = $found['root'];
$post = $found['post'];
// using the path to the root post, we can know the post's depth
$rootPath = $this->rootLoader->getTreeRepo()->findRootPath($postId);
$post->setDepth(count($rootPath) - 1);
$post->setRootPost($found['root']);
}
if ($this->permissions->isAllowed($topicTitle, 'view') && $this->permissions->isAllowed($post, 'view')) {
return $post;
}
$this->addError('moderation', $this->context->msg('flow-error-not-allowed'));
return null;
}
