first commit

app/Helpers/TreeHelper.php

@@ -0,0 +1,196 @@
+<?php
+
+namespace App\Helpers;
+
+class TreeHelper
+{
+    /**
+     * 获取完整的树结构，包含祖先节点
+     */
+    const INCLUDE_ANCESTORS = 1;
+
+    /**
+     * 获取部分树，不包含祖先节点
+     */
+    const EXCLUDE_ANCESTORS = 0;
+
+    /**
+     * 数据
+     * @var array
+     */
+    protected array $data = [];
+
+    /**
+     * 哈希树
+     * @var array
+     */
+    protected array $hashTree = [];
+
+    /**
+     * 父级字段名
+     * @var string
+     */
+    protected string $pidName = 'pid';
+
+    /**
+     * @param $data
+     * @param string $pid_name
+     */
+    public function __construct($data, string $pid_name = 'pid')
+    {
+        $this->pidName = $pid_name;
+        if (is_object($data) && method_exists($data, 'toArray')) {
+            $this->data = $data->toArray();
+        } else {
+            $this->data = (array)$data;
+            $this->data = array_map(function ($item) {
+                if (is_object($item) && method_exists($item, 'toArray')) {
+                    return $item->toArray();
+                }
+                return $item;
+            }, $this->data);
+        }
+        $this->hashTree = $this->getHashTree();
+    }
+
+    /**
+     * 获取子孙节点
+     * @param array $include
+     * @param bool $with_self
+     * @return array
+     */
+    protected function getDescendant(array $include, bool $with_self = false): array
+    {
+        $items = [];
+        foreach ($include as $id) {
+            if (!isset($this->hashTree[$id])) {
+                return [];
+            }
+            if ($with_self) {
+                $item = $this->hashTree[$id];
+                unset($item['children']);
+                $items[$item['id']] = $item;
+            }
+            foreach ($this->hashTree[$id]['children'] ?? [] as $item) {
+                unset($item['children']);
+                $items[$item['id']] = $item;
+                foreach ($this->getDescendant([$item['id']]) as $it) {
+                    $items[$it['id']] = $it;
+                }
+            }
+        }
+        return array_values($items);
+    }
+
+    /**
+     * 获取哈希树
+     * @param array $data
+     * @return array
+     */
+    protected function getHashTree(array $data = []): array
+    {
+        $data = $data ?: $this->data;
+        $hash_tree = [];
+        foreach ($data as $item) {
+            $hash_tree[$item['id']] = $item;
+        }
+        foreach ($hash_tree as $index => $item) {
+            if ($item[$this->pidName] && isset($hash_tree[$item[$this->pidName]])) {
+                $hash_tree[$item[$this->pidName]]['children'][$hash_tree[$index]['id']] = &$hash_tree[$index];
+            }
+        }
+        return $hash_tree;
+    }
+
+    /**
+     * 获取树
+     * @param array $include
+     * @param int $type
+     * @return array|null
+     */
+    protected function _getTree(array $include = [], int $type = 1): ?array
+    {
+        // $type === static::EXCLUDE_ANCESTORS
+        if ($type === static::EXCLUDE_ANCESTORS) {
+            $items = [];
+            $include = array_unique($include);
+            foreach ($include as $id) {
+                if (!isset($this->hashTree[$id])) {
+                    return [];
+                }
+                $items[] = $this->hashTree[$id];
+            }
+            return static::arrayValues($items);
+        }
+
+        // $type === static::INCLUDE_ANCESTORS
+        $hash_tree = $this->hashTree;
+        $items = [];
+        if ($include) {
+            $map = [];
+            foreach ($include as $id) {
+                if (!isset($hash_tree[$id])) {
+                    continue;
+                }
+                $item = $hash_tree[$id];
+                $max_depth = 100;
+                while ($max_depth-- > 0 && $item[$this->pidName] && isset($hash_tree[$item[$this->pidName]])) {
+                    $last_item = $item;
+                    $pid = $item[$this->pidName];
+                    $item = $hash_tree[$pid];
+                    $item_id = $item['id'];
+                    if (empty($map[$item_id])) {
+                        $map[$item_id] = 1;
+                        $hash_tree[$pid]['children'] = [];
+                    }
+                    $hash_tree[$pid]['children'][$last_item['id']] = $last_item;
+                    $item = $hash_tree[$pid];
+                }
+                $items[$item['id']] = $item;
+            }
+        } else {
+            $items = $hash_tree;
+        }
+        $formatted_items = [];
+        foreach ($items as $item) {
+            if (!$item[$this->pidName] || !isset($hash_tree[$item[$this->pidName]])) {
+                $formatted_items[] = $item;
+            }
+        }
+
+        return static::arrayValues($formatted_items);
+    }
+
+    /**
+     * 递归重建数组下标
+     * @param $array
+     * @return array
+     */
+    public static function arrayValues($array): array
+    {
+        if (!$array) {
+            return [];
+        }
+        if (!isset($array['children'])) {
+            $current = current($array);
+            if (!is_array($current)) {
+                return $array;
+            }
+            $tree = array_values($array);
+            foreach ($tree as $index => $item) {
+                $tree[$index] = static::arrayValues($item);
+            }
+            return $tree;
+        }
+        $array['children'] = array_values($array['children']);
+        foreach ($array['children'] as $index => $child) {
+            $array['children'][$index] = static::arrayValues($child);
+        }
+        return $array;
+    }
+
+    public static function getTree($data)
+    {
+        return (new self($data))->_getTree();
+    }
+}