From 5986370cd48e5130382e7d3255c246eb3f348bb0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C5=91cze=20Bence?= <bence@pocze.ch>
Date: Mon, 1 May 2023 14:29:11 +0200
Subject: [PATCH] make it possible to use the same table in multiple joins

---
 src/PersistentData/PersistentDataManager.php | 32 ++++++++++++++++----
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/src/PersistentData/PersistentDataManager.php b/src/PersistentData/PersistentDataManager.php
index f87f022..42182dc 100644
--- a/src/PersistentData/PersistentDataManager.php
+++ b/src/PersistentData/PersistentDataManager.php
@@ -150,7 +150,8 @@ class PersistentDataManager implements IPersistentDataManager
 
             $columns = array_merge($columns, $this->getRelationColumns($relations, $withRelations));
 
-            $this->leftJoinRelations($select, $table, $relations, $withRelations);
+            $alreadyUsedTableAliases = [$table => true];
+            $this->leftJoinRelations($select, $table, $relations, $withRelations, $alreadyUsedTableAliases);
             $select->columns($columns);
         } else {
             $select->columns($columns);
@@ -179,20 +180,39 @@ class PersistentDataManager implements IPersistentDataManager
         return $columns;
     }
 
-    private function leftJoinRelations(Select $select, string $table, array $relations, array $withRelations): void
+    private function leftJoinRelations(Select $select, string $table, array $relations, array $withRelations, array &$alreadyUsedTableAliases): void
     {
         foreach ($relations as $relation => $relationType) {
-            $relationTable = call_user_func([$relationType, 'getTable']);
+            $relationTable = $this->generateTableAlias($select, call_user_func([$relationType, 'getTable']), $alreadyUsedTableAliases);
             $select->leftJoin($relationTable, [$relationTable, 'id'], '=', [$table, $relation . '_id']);
 
-            $nextOrderRelations = call_user_func([$relationType, 'getRelations']);
+            $relationsOfRelation = call_user_func([$relationType, 'getRelations']);
             if (count($withRelations)) {
-                $nextOrderRelations = array_intersect_key($nextOrderRelations, array_flip($withRelations));
+                $relationsOfRelation = array_intersect_key($relationsOfRelation, array_flip($withRelations));
             }
-            $this->leftJoinRelations($select, $relationTable, $nextOrderRelations, $withRelations);
+            $this->leftJoinRelations($select, $relationTable, $relationsOfRelation, $withRelations, $alreadyUsedTableAliases);
         }
     }
 
+    private function generateTableAlias(Select $select, string $table, array &$alreadyUsedTableAliases)
+    {
+        if (!isset($alreadyUsedTableAliases[$table])) {
+            $alreadyUsedTableAliases[$table] = true;
+            return $table;
+        }
+
+        $i = 2;
+        do {
+            $alias = $table[0] . $i;
+            $i++;
+        } while (isset($alreadyUsedTableAliases[$alias]));
+
+        $select->setTableAliases([$alias => $table]);
+        $alreadyUsedTableAliases[$alias] = true;
+
+        return $alias;
+    }
+
     private function fillWithData(array &$data, Model $model, array $withRelations = [], ?string $modelKey = null): void
     {
         $relations = $model::getRelations();