public function copyPage($pg)
{
$key = $pg - 1;
// Check if the page exists.
if (!array_key_exists($key, $this->pages)) {
throw new Exception('Error: That page does not exist.');
}
$pi = $this->lastIndex($this->objects) + 1;
$ci = $this->lastIndex($this->objects) + 2;
$this->objects[$pi] = new Object\Page($this->objects[$this->pages[$key]]);
$this->objects[$pi]->index = $pi;
// Duplicate the page's content objects.
$oldContent = $this->objects[$pi]->content;
unset($this->objects[$pi]->content);
foreach ($oldContent as $key => $value) {
$this->objects[$ci] = new Object\Object((string) $this->objects[$value]);
$this->objects[$ci]->index = $ci;
$this->objects[$pi]->content[] = $ci;
$ci += 1;
}
// Finalize related page variables and objects.
$this->curPage = null === $this->curPage ? 0 : $this->lastIndex($this->pages) + 1;
$this->pages[$this->curPage] = $pi;
$this->objects[$this->parent]->count += 1;
$this->objects[$this->parent]->kids[] = $pi;
return $this;
}