setTemplate($template); } public function setTemplate($template) { $this->template = $template; $this->nodes = $this->getNodes($template); $this->rootIds = $this->getRootIds($template); $this->adjacencyList = $this->buildAdjacencyList($template); } public function format($format) { $output = ''; foreach ($this->rootIds as $rootId) { $this->walkTree($this->nodes[$rootId], $output, $format); } return $output; } public function __toString() { $this->format(static::FORMAT_TEXT); } protected function buildAdjacencyList($template) { $adjacencyList = []; foreach ($template as $node) { if ($node['parentId'] !== null) { if (isset($adjacencyList[$node['parentId']])) { $adjacencyList[$node['parentId']][] = $node['id']; } else { $adjacencyList[$node['parentId']] = [$node['id']]; } } } return $adjacencyList; } protected function getNodes($template) { $nodes = []; foreach ($template as $node) { $nodes[$node['id']] = $node; } return $nodes; } protected function getRootIds($template) { $rootIds = []; foreach ($template as $node) { if ($node['parentId'] === null) { $rootIds[] = $node['id']; } } if ($rootIds !== []) { return $rootIds; } else { throw new Exception('Parent node do not exists.'); } } protected function walkTree($node, &$output, $format, $depth = 0) { switch ($format) { case Tree::FORMAT_TEXT: $output .= $this->formatNodeAsText($node['text'], $depth); break; case Tree::FORMAT_HTML: $output .= $this->formatNodeAsHtml($node['text'], $depth); break; default: $output .= $this->formatNodeAsText($node['text'], $depth); } $depth += 1; if (isset($this->adjacencyList[$node['id']])) { foreach ($this->adjacencyList[$node['id']] as $childId) { $this->walkTree($this->nodes[$childId], $output, $format, $depth); } } } protected function formatNodeAsText($nodeText, $depth) { return str_repeat(' ', $depth) . $nodeText . "\r\n"; } protected function formatNodeAsHtml($nodeText, $depth) { return '

' . $nodeText . '

'; } } $template = array( array("id" => 1, "parentId" => null, "text" => "Первая строка"), array("id" => 2, "parentId" => 3, "text" => "Вторая строка"), array("id" => 3, "parentId" => 1, "text" => "Третья строка"), array("id" => 4, "parentId" => 1, "text" => "Четвертая строка"), array("id" => 5, "parentId" => null, "text" => "Пятая строка"), array("id" => 6, "parentId" => 5, "text" => "Шестая строка") ); $tree = new Tree($template); echo $tree->format(Tree::FORMAT_TEXT);