From c3d09fd6015a4041d191a62f4ce5f5011784a5e7 Mon Sep 17 00:00:00 2001
From: Johannes Meyer <johannes.meyer@icinga.com>
Date: Wed, 26 Jul 2023 17:04:50 +0200
Subject: [PATCH] Introduce `Icinga\Module\Businessprocess\Common\Sort`

---
 library/Businessprocess/Common/Sort.php | 154 ++++++++++++++++++++++++
 1 file changed, 154 insertions(+)
 create mode 100644 library/Businessprocess/Common/Sort.php

diff --git a/library/Businessprocess/Common/Sort.php b/library/Businessprocess/Common/Sort.php
new file mode 100644
index 0000000..3b0f6d4
--- /dev/null
+++ b/library/Businessprocess/Common/Sort.php
@@ -0,0 +1,154 @@
+<?php
+// Icinga Business Process Modelling | (c) 2023 Icinga GmbH | GPLv2
+
+namespace Icinga\Module\Businessprocess\Common;
+
+use Icinga\Module\Businessprocess\BpNode;
+use Icinga\Module\Businessprocess\Node;
+use InvalidArgumentException;
+use ipl\Stdlib\Str;
+
+trait Sort
+{
+    /** @var string Current sort specification */
+    protected $sort;
+
+    /** @var callable Actual sorting function */
+    protected $sortFn;
+
+    /**
+     * Get the sort specification
+     *
+     * @return ?string
+     */
+    public function getSort(): ?string
+    {
+        return $this->sort;
+    }
+
+    /**
+     * Set the sort specification
+     *
+     * @param string $sort
+     *
+     * @return $this
+     *
+     * @throws InvalidArgumentException When sorting according to the specified specification is not possible
+     */
+    public function setSort(string $sort): self
+    {
+        list($sortBy, $direction) = Str::symmetricSplit($sort, ' ', 2, 'asc');
+
+        switch ($sortBy) {
+            case 'manual':
+                if ($direction === 'asc') {
+                    $this->sortFn = function (array &$nodes) {
+                        $firstNode = reset($nodes);
+                        if ($firstNode instanceof BpNode && $firstNode->getDisplay() > 0) {
+                            $nodes = self::applyManualSorting($nodes);
+                        }
+
+                        // Child nodes don't need to be ordered in this case, their implicit order is significant
+                    };
+                } else {
+                    $this->sortFn = function (array &$nodes) {
+                        $firstNode = reset($nodes);
+                        if ($firstNode instanceof BpNode && $firstNode->getDisplay() > 0) {
+                            uasort($nodes, function (BpNode $a, BpNode $b) {
+                                return $b->getDisplay() <=> $a->getDisplay();
+                            });
+                        } else {
+                            $nodes = array_reverse($nodes);
+                        }
+                    };
+                }
+
+                break;
+            case 'display_name':
+                if ($direction === 'asc') {
+                    $this->sortFn = function (array &$nodes) {
+                        uasort($nodes, function (Node $a, Node $b) {
+                            return strnatcasecmp(
+                                $a->getAlias() ?? $a->getName(),
+                                $b->getAlias() ?? $b->getName()
+                            );
+                        });
+                    };
+                } else {
+                    $this->sortFn = function (array &$nodes) {
+                        uasort($nodes, function (Node $a, Node $b) {
+                            return strnatcasecmp(
+                                $b->getAlias() ?? $b->getName(),
+                                $a->getAlias() ?? $a->getName()
+                            );
+                        });
+                    };
+                }
+
+                break;
+            case 'state':
+                if ($direction === 'asc') {
+                    $this->sortFn = function (array &$nodes) {
+                        uasort($nodes, function (Node $a, Node $b) {
+                            return $a->getSortingState() <=> $b->getSortingState();
+                        });
+                    };
+                } else {
+                    $this->sortFn = function (array &$nodes) {
+                        uasort($nodes, function (Node $a, Node $b) {
+                            return $b->getSortingState() <=> $a->getSortingState();
+                        });
+                    };
+                }
+
+                break;
+            default:
+                throw new InvalidArgumentException(sprintf(
+                    "Can't sort by %s. It's only possible to sort by manual order, display_name or state",
+                    $sortBy
+                ));
+        }
+
+        $this->sort = $sort;
+
+        return $this;
+    }
+
+    /**
+     * Sort the given nodes as specified by {@see setSort()}
+     *
+     * If {@see setSort()} has not been called yet, the default sort specification is used
+     *
+     * @param array $nodes
+     *
+     * @return array
+     */
+    public function sort(array $nodes): array
+    {
+        if (empty($nodes)) {
+            return $nodes;
+        }
+
+        if ($this->sortFn !== null) {
+            call_user_func_array($this->sortFn, [&$nodes]);
+        }
+
+        return $nodes;
+    }
+
+    /**
+     * Apply manual sort order on the given process nodes
+     *
+     * @param array $bpNodes
+     *
+     * @return array
+     */
+    public static function applyManualSorting(array $bpNodes): array
+    {
+        uasort($bpNodes, function (BpNode $a, BpNode $b) {
+            return $a->getDisplay() <=> $b->getDisplay();
+        });
+
+        return $bpNodes;
+    }
+}