Core v2.3, N:M Relations

Core/Objects/DatabaseEntity/ApiKey.class.php

@@ -3,6 +3,7 @@
 namespace Core\Objects\DatabaseEntity;
 
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class ApiKey extends DatabaseEntity {
 

Core/Objects/DatabaseEntity/Attribute/Multiple.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Core\Objects\DatabaseEntity\Attribute;
+
+#[\Attribute(\Attribute::TARGET_PROPERTY)]
+class Multiple {
+
+  private string $className;
+
+  public function __construct(string $className) {
+    $this->className = $className;
+  }
+
+  public function getClassName(): string {
+    return $this->className;
+  }
+
+}

Core/Objects/DatabaseEntity/Controller/DatabaseEntity.class.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Core\Objects\DatabaseEntity;
+namespace Core\Objects\DatabaseEntity\Controller;
 
 use Core\Driver\SQL\Condition\Compare;
 use Core\Driver\SQL\Condition\Condition;
@@ -8,6 +8,13 @@ use Core\Driver\SQL\SQL;
 
 abstract class DatabaseEntity {
 
+  protected static array $entityLogConfig = [
+    "insert" => false,
+    "update" => false,
+    "delete" => false,
+    "lifetime" => null,
+  ];
+
   private static array $handlers = [];
   protected ?int $id;
 
@@ -51,8 +58,8 @@ abstract class DatabaseEntity {
     return $res !== false && $res[0]["count"] !== 0;
   }
 
-  public static function findBuilder(SQL $sql): DatabaseEntityQuery {
-    return DatabaseEntityQuery::fetchOne(self::getHandler($sql));
+  public static function findBy(DatabaseEntityQuery $dbQuery): static|array|bool|null {
+    return $dbQuery->execute();
   }
 
   public static function findAll(SQL $sql, ?Condition $condition = null): ?array {
@@ -60,17 +67,22 @@ abstract class DatabaseEntity {
     return $handler->fetchMultiple($condition);
   }
 
-  public static function findAllBuilder(SQL $sql): DatabaseEntityQuery {
-    return DatabaseEntityQuery::fetchAll(self::getHandler($sql));
+  public static function createBuilder(SQL $sql, bool $one): DatabaseEntityQuery {
+    if ($one) {
+      return DatabaseEntityQuery::fetchOne(self::getHandler($sql));
+    } else {
+      return DatabaseEntityQuery::fetchAll(self::getHandler($sql));
+    }
   }
 
-  public function save(SQL $sql, ?array $columns = null): bool {
+  public function save(SQL $sql, ?array $columns = null, bool $saveNM = false): bool {
     $handler = self::getHandler($sql);
-    $res = $handler->insertOrUpdate($this, $columns);
+    $res = $handler->insertOrUpdate($this, $columns, $saveNM);
     if ($res === false) {
       return false;
     } else if ($this->id === null) {
       $this->id = $res;
+      $handler->insertNM($this);
     }
 
     return true;
@@ -127,4 +139,22 @@ abstract class DatabaseEntity {
   public function getId(): ?int {
     return $this->id;
   }
+
+  public static function count(SQL $sql, ?Condition $condition = null): int|bool {
+    $handler = self::getHandler($sql);
+    $query = $sql->select($sql->count())
+      ->from($handler->getTableName());
+
+    if ($condition) {
+      $query->where($condition);
+    }
+
+    $res = $query->execute();
+
+    if (!empty($res)) {
+      return $res[0]["count"];
+    }
+
+    return false;
+  }
 }

Core/Objects/DatabaseEntity/Controller/DatabaseEntityHandler.php

@@ -1,33 +1,46 @@
 <?php
 
-namespace Core\Objects\DatabaseEntity;
+namespace Core\Objects\DatabaseEntity\Controller;
 
 use Core\Driver\Logger\Logger;
 use Core\Driver\SQL\Column\BoolColumn;
+use Core\Driver\SQL\Column\Column;
 use Core\Driver\SQL\Column\DateTimeColumn;
 use Core\Driver\SQL\Column\EnumColumn;
 use Core\Driver\SQL\Column\IntColumn;
 use Core\Driver\SQL\Column\JsonColumn;
 use Core\Driver\SQL\Column\StringColumn;
 use Core\Driver\SQL\Condition\Compare;
+use Core\Driver\SQL\Condition\CondAnd;
+use Core\Driver\SQL\Condition\CondBool;
+use Core\Driver\SQL\Condition\CondIn;
 use Core\Driver\SQL\Condition\Condition;
 use Core\Driver\SQL\Column\DoubleColumn;
 use Core\Driver\SQL\Column\FloatColumn;
+use Core\Driver\SQL\Condition\CondNot;
+use Core\Driver\SQL\Condition\CondOr;
 use Core\Driver\SQL\Constraint\ForeignKey;
+use Core\Driver\SQL\Join;
+use Core\Driver\SQL\Query\CreateProcedure;
 use Core\Driver\SQL\Query\CreateTable;
+use Core\Driver\SQL\Query\Insert;
 use Core\Driver\SQL\Query\Select;
 use Core\Driver\SQL\SQL;
 use Core\Driver\SQL\Strategy\CascadeStrategy;
 use Core\Driver\SQL\Strategy\SetNullStrategy;
+use Core\Driver\SQL\Strategy\UpdateStrategy;
+use Core\Driver\SQL\Type\CurrentColumn;
+use Core\Driver\SQL\Type\CurrentTable;
 use Core\Objects\DatabaseEntity\Attribute\Enum;
 use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
 use Core\Objects\DatabaseEntity\Attribute\Json;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Attribute\Multiple;
 use Core\Objects\DatabaseEntity\Attribute\Transient;
 use Core\Objects\DatabaseEntity\Attribute\Unique;
 use PHPUnit\Util\Exception;
 
-class DatabaseEntityHandler {
+class DatabaseEntityHandler implements Persistable {
 
   private \ReflectionClass $entityClass;
   private string $tableName;
@@ -35,6 +48,7 @@ class DatabaseEntityHandler {
   private array $properties;
   private array $relations;
   private array $constraints;
+  private array $nmRelations;
   private SQL $sql;
   private Logger $logger;
 
@@ -50,8 +64,9 @@ class DatabaseEntityHandler {
     $this->tableName = $this->entityClass->getShortName();
     $this->columns = [];     // property name => database column name
     $this->properties = [];  // property name => \ReflectionProperty
-    $this->relations = [];   // property name => referenced table name
+    $this->relations = [];   // property name => DatabaseEntityHandler
     $this->constraints = []; // \Driver\SQL\Constraint\Constraint
+    $this->nmRelations = [];    // table name => NMRelation
 
     foreach ($this->entityClass->getProperties() as $property) {
       $propertyName = $property->getName();
@@ -60,6 +75,10 @@ class DatabaseEntityHandler {
         continue;
       }
 
+      if ($property->isStatic()) {
+        continue;
+      }
+
       $propertyType = $property->getType();
       $columnName = self::getColumnName($propertyName);
       if (!($propertyType instanceof \ReflectionNamedType)) {
@@ -93,18 +112,46 @@ class DatabaseEntityHandler {
         $this->columns[$propertyName] = new BoolColumn($columnName, $defaultValue ?? false);
       } else if ($propertyTypeName === 'DateTime') {
         $this->columns[$propertyName] = new DateTimeColumn($columnName, $nullable, $defaultValue);
-      /*} else if ($propertyName === 'array') {
-        $many = self::getAttribute($property, Many::class);
-        if ($many) {
-          $requestedType = $many->getValue();
-          if (isClass($requestedType)) {
-            $requestedClass = new \ReflectionClass($requestedType);
+        /*} else if ($propertyName === 'array') {
+          $many = self::getAttribute($property, Many::class);
+          if ($many) {
+            $requestedType = $many->getValue();
+            if (isClass($requestedType)) {
+              $requestedClass = new \ReflectionClass($requestedType);
+            } else {
+              $this->raiseError("Cannot persist class '$className': Property '$propertyName' has non persist-able type: $requestedType");
+            }
           } else {
-            $this->raiseError("Cannot persist class '$className': Property '$propertyName' has non persist-able type: $requestedType");
+            $this->raiseError("Cannot persist class '$className': Property '$propertyName' has non persist-able type: $propertyTypeName");
+          }*/
+      } else if ($propertyTypeName === "array") {
+        $multiple = self::getAttribute($property, Multiple::class);
+        if (!$multiple) {
+          $this->raiseError("Cannot persist class '$className': Property '$propertyName' has non persist-able type: $propertyTypeName. " .
+                            "Is the 'Multiple' attribute missing?");
+        }
+
+        try {
+          $refClass = $multiple->getClassName();
+          $requestedClass = new \ReflectionClass($refClass);
+          if ($requestedClass->isSubclassOf(DatabaseEntity::class)) {
+            $nmTableName = NMRelation::buildTableName($this->getTableName(), $requestedClass->getShortName());
+            $nmRelation = $this->nmRelations[$nmTableName] ?? null;
+            if (!$nmRelation) {
+              $otherHandler = DatabaseEntity::getHandler($this->sql, $requestedClass);
+              $otherNM = $otherHandler->getNMRelations();
+              $nmRelation = $otherNM[$nmTableName] ?? (new NMRelation($this, $otherHandler));
+              $this->nmRelations[$nmTableName] = $nmRelation;
+            }
+
+            $this->nmRelations[$nmTableName]->addProperty($this, $property);
+          } else {
+            $this->raiseError("Cannot persist class '$className': Property '$propertyName' of type multiple can " .
+                              "only reference DatabaseEntity types, but got: $refClass");
           }
-        } else {
-          $this->raiseError("Cannot persist class '$className': Property '$propertyName' has non persist-able type: $propertyTypeName");
-        }*/
+        } catch (\Exception $ex) {
+          $this->raiseError("Cannot persist class '$className' property '$propertyTypeName': " . $ex->getMessage());
+        }
       } else if ($propertyTypeName !== "mixed") {
         try {
           $requestedClass = new \ReflectionClass($propertyTypeName);
@@ -167,6 +214,10 @@ class DatabaseEntityHandler {
     return $this->relations;
   }
 
+  public function getNMRelations(): array {
+    return $this->nmRelations;
+  }
+
   public function getColumnNames(): array {
     $columns = ["$this->tableName.id"];
     foreach ($this->columns as $column) {
@@ -238,6 +289,14 @@ class DatabaseEntityHandler {
         }
       }
 
+      // init n:m / 1:n properties with empty arrays
+      foreach ($this->nmRelations as $nmRelation) {
+        foreach ($nmRelation->getProperties($this) as $property) {
+          $property->setAccessible(true);
+          $property->setValue($entity, []);
+        }
+      }
+
       $this->properties["id"]->setAccessible(true);
       $this->properties["id"]->setValue($entity, $row["id"]);
       $entity->postFetch($this->sql, $row);
@@ -248,6 +307,190 @@ class DatabaseEntityHandler {
     }
   }
 
+  public function updateNM(DatabaseEntity $entity): bool {
+    if (empty($this->nmRelations)) {
+      return true;
+    }
+
+    foreach ($this->nmRelations as $nmTable => $nmRelation) {
+
+      $thisIdColumn = $nmRelation->getIdColumn($this);
+      $thisTableName = $this->getTableName();
+      $dataColumns = $nmRelation->getDataColumns();
+      $otherHandler = $nmRelation->getOtherHandler($this);
+      $refIdColumn = $nmRelation->getIdColumn($otherHandler);
+
+
+      // delete from n:m table if no longer exists
+      $deleteStatement = $this->sql->delete($nmTable)
+        ->where(new Compare($thisIdColumn, $entity->getId()));
+
+      if (!empty($dataColumns)) {
+        $conditions = [];
+        foreach ($dataColumns[$thisTableName] as $propertyName => $columnName) {
+          $property = $this->properties[$propertyName];
+          $entityIds = array_keys($property->getValue($entity));
+          if (!empty($entityIds)) {
+            $conditions[] = new CondAnd(
+              new CondBool($columnName),
+              new CondNot(new CondIn(new Column($refIdColumn), $entityIds)),
+            );
+          }
+        }
+
+        if (!empty($conditions)) {
+          $deleteStatement->where(new CondOr(...$conditions));
+        }
+      } else {
+        $property = next($nmRelation->getProperties($this));
+        $entityIds = array_keys($property->getValue($entity));
+        if (!empty($entityIds)) {
+          $deleteStatement->where(
+            new CondNot(new CondIn(new Column($refIdColumn), $entityIds))
+          );
+        }
+      }
+
+      $deleteStatement->execute();
+    }
+
+    return $this->insertNM($entity, true);
+  }
+
+  public function insertNM(DatabaseEntity $entity, bool $ignoreExisting = true): bool {
+
+    if (empty($this->nmRelations)) {
+      return true;
+    }
+
+    $success = true;
+    foreach ($this->nmRelations as $nmTable => $nmRelation) {
+      $otherHandler = $nmRelation->getOtherHandler($this);
+      $thisIdColumn = $nmRelation->getIdColumn($this);
+      $thisTableName = $this->getTableName();
+      $refIdColumn = $nmRelation->getIdColumn($otherHandler);
+      $dataColumns = $nmRelation->getDataColumns();
+
+      $columns = [
+        $thisIdColumn,
+        $refIdColumn,
+      ];
+
+      if (!empty($dataColumns)) {
+        $columns = array_merge($columns, array_values($dataColumns[$thisTableName]));
+      }
+
+      $statement = $this->sql->insert($nmTable, $columns);
+      if ($ignoreExisting) {
+        $statement->onDuplicateKeyStrategy(new UpdateStrategy($nmRelation->getAllColumns(), [
+          $thisIdColumn => $entity->getId()
+        ]));
+      }
+
+      foreach ($nmRelation->getProperties($this) as $property) {
+        $property->setAccessible(true);
+        $relEntities = $property->getValue($entity);
+        foreach ($relEntities as $relEntity) {
+          $nmRow = [$entity->getId(), $relEntity->getId()];
+          if (!empty($dataColumns)) {
+            foreach (array_keys($dataColumns[$thisTableName]) as $propertyName) {
+              $nmRow[] = $property->getName() === $propertyName;
+            }
+          }
+          $statement->addRow(...$nmRow);
+        }
+      }
+
+      $success = $statement->execute() && $success;
+    }
+
+    return $success;
+  }
+
+  public function fetchNMRelations(array $entities, bool $recursive = false) {
+
+    if ($recursive) {
+      foreach ($entities as $entity) {
+        foreach ($this->relations as $propertyName => $relHandler) {
+          $relEntity = $this->properties[$propertyName]->getValue($entity);
+          if ($relEntity) {
+            $relHandler->fetchNMRelations([$relEntity->getId() => $relEntity], true);
+          }
+        }
+      }
+    }
+
+    if (empty($this->nmRelations)) {
+      return;
+    }
+
+    $entityIds = array_keys($entities);
+    foreach ($this->nmRelations as $nmTable => $nmRelation) {
+      $otherHandler = $nmRelation->getOtherHandler($this);
+
+      $thisIdColumn = $nmRelation->getIdColumn($this);
+      $thisProperties = $nmRelation->getProperties($this);
+      $thisTableName = $this->getTableName();
+
+      $refIdColumn = $nmRelation->getIdColumn($otherHandler);
+      $refProperties = $nmRelation->getProperties($otherHandler);
+      $refTableName = $otherHandler->getTableName();
+
+      $dataColumns = $nmRelation->getDataColumns();
+
+      $relEntityQuery = DatabaseEntityQuery::fetchAll($otherHandler)
+        ->addJoin(new Join("INNER", $nmTable, "$nmTable.$refIdColumn", "$refTableName.id"))
+        ->where(new CondIn(new Column($thisIdColumn), $entityIds))
+        ->getQuery();
+
+      $relEntityQuery->addColumn($thisIdColumn);
+      foreach ($dataColumns as $tableDataColumns) {
+        foreach ($tableDataColumns as $columnName) {
+          $relEntityQuery->addColumn($columnName);
+        }
+      }
+
+      $rows = $relEntityQuery->execute();
+      if (!is_array($rows)) {
+        $this->logger->error("Error fetching n:m relations from table: '$nmTable': " . $this->sql->getLastError());
+        return;
+      }
+
+      $relEntities = [];
+      foreach ($rows as $row) {
+        $relId = $row["id"];
+        if (!isset($relEntities[$relId])) {
+          $relEntity = $otherHandler->entityFromRow($row);
+          $relEntities[$relId] = $relEntity;
+        }
+
+        $thisEntity = $entities[$row[$thisIdColumn]];
+        $relEntity = $relEntities[$relId];
+        $mappings = [
+          [$refProperties, $refTableName, $relEntity, $thisEntity],
+          [$thisProperties, $thisTableName, $thisEntity, $relEntity],
+        ];
+
+        foreach ($mappings as $mapping) {
+          list($properties, $tableName, $targetEntity, $entityToAdd) = $mapping;
+          foreach ($properties as $propertyName => $property) {
+            $addToProperty = empty($dataColumns);
+            if (!$addToProperty) {
+              $columnName = $dataColumns[$tableName][$propertyName] ?? null;
+              $addToProperty = ($columnName && $this->sql->parseBool($row[$columnName]));
+            }
+
+            if ($addToProperty) {
+              $targetArray = $property->getValue($targetEntity);
+              $targetArray[$entityToAdd->getId()] = $entityToAdd;
+              $property->setValue($targetEntity, $targetArray);
+            }
+          }
+        }
+      }
+    }
+  }
+
   public function getSelectQuery(): Select {
     return $this->sql->select(...$this->getColumnNames())
       ->from($this->tableName);
@@ -259,11 +502,14 @@ class DatabaseEntityHandler {
       ->first()
       ->execute();
 
-    if ($res === false || $res === null) {
-      return $res;
-    } else {
-      return $this->entityFromRow($res);
+    if ($res !== false && $res !== null) {
+      $res = $this->entityFromRow($res);
+      if ($res instanceof DatabaseEntity) {
+        $this->fetchNMRelations([$res->getId() => $res]);
+      }
     }
+
+    return $res;
   }
 
   public function fetchMultiple(?Condition $condition = null): ?array {
@@ -284,12 +530,56 @@ class DatabaseEntityHandler {
           $entities[$entity->getId()] = $entity;
         }
       }
+
+      $this->fetchNMRelations($entities);
       return $entities;
     }
   }
 
-  public function getTableQuery(): CreateTable {
-    $query = $this->sql->createTable($this->tableName)
+  public function getCreateQueries(SQL $sql): array {
+
+    $queries = [];
+    $queries[] = $this->getTableQuery($sql);
+
+    $table = $this->getTableName();
+    $entityLogConfig = $this->entityClass->getProperty("entityLogConfig");
+    $entityLogConfig->setAccessible(true);
+    $entityLogConfig = $entityLogConfig->getValue();
+
+    if (isset($entityLogConfig["insert"]) && $entityLogConfig["insert"] === true) {
+      $queries[] = $sql->createTrigger("${table}_trg_insert")
+        ->after()->insert($table)
+        ->exec(new CreateProcedure($sql, "InsertEntityLog"), [
+          "tableName" => new CurrentTable(),
+          "entityId" => new CurrentColumn("id"),
+          "lifetime" => $entityLogConfig["lifetime"] ?? 90,
+        ]);
+    }
+
+    if (isset($entityLogConfig["update"]) && $entityLogConfig["update"] === true) {
+      $queries[] = $sql->createTrigger("${table}_trg_update")
+        ->after()->update($table)
+        ->exec(new CreateProcedure($sql, "UpdateEntityLog"), [
+          "tableName" => new CurrentTable(),
+          "entityId" => new CurrentColumn("id"),
+        ]);
+    }
+
+    if (isset($entityLogConfig["delete"]) && $entityLogConfig["delete"] === true) {
+      $queries[] = $sql->createTrigger("${table}_trg_delete")
+        ->after()->delete($table)
+        ->exec(new CreateProcedure($sql, "DeleteEntityLog"), [
+          "tableName" => new CurrentTable(),
+          "entityId" => new CurrentColumn("id"),
+        ]);
+    }
+
+
+    return $queries;
+  }
+
+  public function getTableQuery(SQL $sql): CreateTable {
+    $query = $sql->createTable($this->tableName)
       ->onlyIfNotExists()
       ->addSerial("id")
       ->primaryKey("id");
@@ -305,12 +595,7 @@ class DatabaseEntityHandler {
     return $query;
   }
 
-  public function createTable(): bool {
-    $query = $this->getTableQuery();
-    return $query->execute();
-  }
-
-  private function prepareRow(DatabaseEntity $entity, string $action, ?array $columns = null) {
+  private function prepareRow(DatabaseEntity $entity, string $action, ?array $columns = null): bool|array {
     $row = [];
     foreach ($this->columns as $propertyName => $column) {
       if ($columns && !in_array($column->getName(), $columns)) {
@@ -344,7 +629,7 @@ class DatabaseEntityHandler {
     return $row;
   }
 
-  public function update(DatabaseEntity $entity, ?array $columns = null) {
+  public function update(DatabaseEntity $entity, ?array $columns = null, bool $saveNM = false) {
     $row = $this->prepareRow($entity, "update", $columns);
     if ($row === false) {
       return false;
@@ -358,10 +643,15 @@ class DatabaseEntityHandler {
       $query->set($columnName, $value);
     }
 
-    return $query->execute();
+    $res = $query->execute();
+    if ($res && $saveNM) {
+      $res = $this->updateNM($entity);
+    }
+
+    return $res;
   }
 
-  public function insert(DatabaseEntity $entity) {
+  public function insert(DatabaseEntity $entity): bool|int {
     $row = $this->prepareRow($entity, "insert");
     if ($row === false) {
       return false;
@@ -391,12 +681,12 @@ class DatabaseEntityHandler {
     }
   }
 
-  public function insertOrUpdate(DatabaseEntity $entity, ?array $columns = null) {
+  public function insertOrUpdate(DatabaseEntity $entity, ?array $columns = null, bool $saveNM = false) {
     $id = $entity->getId();
     if ($id === null) {
       return $this->insert($entity);
     } else {
-      return $this->update($entity, $columns);
+      return $this->update($entity, $columns, $saveNM);
     }
   }
 
@@ -415,4 +705,30 @@ class DatabaseEntityHandler {
   public function getSQL(): SQL {
     return $this->sql;
   }
+
+  public function getInsertQuery(DatabaseEntity|array $entities): ?Insert {
+
+    if (empty($entities)) {
+      return null;
+    }
+
+    $firstEntity = (is_array($entities) ? current($entities) : $entities);
+    $firstRow = $this->prepareRow($firstEntity, "insert");
+
+    $statement = $this->sql->insert($this->tableName, array_keys($firstRow))
+      ->addRow(...array_values($firstRow));
+
+    if (is_array($entities)) {
+      foreach ($entities as $entity) {
+        if ($entity === $firstEntity) {
+          continue;
+        }
+
+        $row = $this->prepareRow($entity, "insert");
+        $statement->addRow(...array_values($row));
+      }
+    }
+
+    return $statement;
+  }
 }

Core/Objects/DatabaseEntity/Controller/DatabaseEntityQuery.class.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Core\Objects\DatabaseEntity;
+namespace Core\Objects\DatabaseEntity\Controller;
 
 use Core\Driver\Logger\Logger;
 use Core\Driver\SQL\Condition\Condition;
@@ -14,18 +14,25 @@ use Core\Driver\SQL\SQL;
 */
 class DatabaseEntityQuery {
 
+  const FETCH_NONE = 0;
+  const FETCH_DIRECT = 1;
+  const FETCH_RECURSIVE = 2;
+
   private Logger $logger;
   private DatabaseEntityHandler $handler;
   private Select $selectQuery;
   private int $resultType;
   private bool $logVerbose;
 
+  private int $fetchSubEntities;
+
   private function __construct(DatabaseEntityHandler $handler, int $resultType) {
     $this->handler = $handler;
     $this->selectQuery = $handler->getSelectQuery();
     $this->logger = new Logger("DB-EntityQuery", $handler->getSQL());
     $this->resultType = $resultType;
     $this->logVerbose = false;
+    $this->fetchSubEntities = self::FETCH_NONE;
 
     if ($this->resultType === SQL::FETCH_ONE) {
       $this->selectQuery->first();
@@ -50,6 +57,11 @@ class DatabaseEntityQuery {
     return $this;
   }
 
+  public function offset(int $offset): static {
+    $this->selectQuery->offset($offset);
+    return $this;
+  }
+
   public function where(Condition ...$condition): DatabaseEntityQuery {
     $this->selectQuery->where(...$condition);
     return $this;
@@ -74,6 +86,7 @@ class DatabaseEntityQuery {
   public function fetchEntities(bool $recursive = false): DatabaseEntityQuery {
 
     // $this->selectQuery->dump();
+    $this->fetchSubEntities = ($recursive ? self::FETCH_RECURSIVE : self::FETCH_DIRECT);
 
     $relIndex = 1;
     foreach ($this->handler->getRelations() as $propertyName => $relationHandler) {
@@ -136,9 +149,19 @@ class DatabaseEntityQuery {
           $entities[$entity->getId()] = $entity;
         }
       }
+
+      if ($this->fetchSubEntities !== self::FETCH_NONE) {
+        $this->handler->fetchNMRelations($entities, $this->fetchSubEntities === self::FETCH_RECURSIVE);
+      }
+
       return $entities;
     } else if ($this->resultType === SQL::FETCH_ONE) {
-      return $this->handler->entityFromRow($res);
+      $entity = $this->handler->entityFromRow($res);
+      if ($entity instanceof DatabaseEntity && $this->fetchSubEntities !== self::FETCH_NONE) {
+        $this->handler->fetchNMRelations([$entity->getId() => $entity], $this->fetchSubEntities === self::FETCH_RECURSIVE);
+      }
+
+      return $entity;
     } else {
       $this->handler->getLogger()->error("Invalid result type for query builder, must be FETCH_ALL or FETCH_ONE");
       return null;
@@ -149,4 +172,8 @@ class DatabaseEntityQuery {
     $this->selectQuery->addJoin($join);
     return $this;
   }
+
+  public function getQuery(): Select {
+    return $this->selectQuery;
+  }
 }

Core/Objects/DatabaseEntity/Controller/NMRelation.class.php

@@ -0,0 +1,134 @@
+<?php
+
+namespace Core\Objects\DatabaseEntity\Controller;
+
+# TODO: Allow more than 2 relations here?
+
+use Core\Driver\SQL\Query\CreateTable;
+use Core\Driver\SQL\SQL;
+use Core\Driver\SQL\Strategy\CascadeStrategy;
+
+class NMRelation implements Persistable {
+
+  private DatabaseEntityHandler $handlerA;
+  private DatabaseEntityHandler $handlerB;
+  private array $properties;
+
+  public function __construct(DatabaseEntityHandler $handlerA, DatabaseEntityHandler $handlerB) {
+    $this->handlerA = $handlerA;
+    $this->handlerB = $handlerB;
+    $tableNameA = $handlerA->getTableName();
+    $tableNameB = $handlerB->getTableName();
+    if ($tableNameA === $tableNameB) {
+      throw new \Exception("Cannot create N:M Relation with only one table");
+    }
+
+    $this->properties = [
+      $tableNameA => [],
+      $tableNameB => [],
+    ];
+  }
+
+  public function addProperty(DatabaseEntityHandler $src, \ReflectionProperty $property): void {
+    $this->properties[$src->getTableName()][$property->getName()] = $property;
+  }
+
+  public function getIdColumn(DatabaseEntityHandler $handler): string {
+    return DatabaseEntityHandler::getColumnName($handler->getTableName()) . "_id";
+  }
+
+  public function getDataColumns(): array {
+
+    $referenceCount = 0;
+    $columnsNeeded = false;
+
+    // if in one of the relations we have multiple references, we need to differentiate
+    foreach ($this->properties as $refProperties) {
+      $referenceCount += count($refProperties);
+      if ($referenceCount > 1) {
+        $columnsNeeded = true;
+        break;
+      }
+    }
+
+    $columns = [];
+    if ($columnsNeeded) {
+      foreach ($this->properties as $tableName => $properties) {
+        $columns[$tableName] = [];
+        foreach ($properties as $property) {
+          $columnName = DatabaseEntityHandler::getColumnName($tableName) . "_" .
+            DatabaseEntityHandler::getColumnName($property->getName());
+          $columns[$tableName][$property->getName()] = $columnName;
+        }
+      }
+    }
+
+    return $columns;
+  }
+
+  public function getAllColumns(): array {
+    $relIdA = $this->getIdColumn($this->handlerA);
+    $relIdB = $this->getIdColumn($this->handlerB);
+
+    $columns = [$relIdA, $relIdB];
+
+    foreach ($this->getDataColumns() as $dataColumns) {
+      foreach ($dataColumns as $columnName) {
+        $columns[] = $columnName;
+      }
+    }
+
+    return $columns;
+  }
+
+  public function getTableQuery(SQL $sql): CreateTable {
+
+    $tableNameA = $this->handlerA->getTableName();
+    $tableNameB = $this->handlerB->getTableName();
+
+    $columns = $this->getAllColumns();
+    list ($relIdA, $relIdB) = $columns;
+    $dataColumns = array_slice($columns, 2);
+    $query = $sql->createTable(self::buildTableName($tableNameA, $tableNameB))
+      ->addInt($relIdA)
+      ->addInt($relIdB)
+      ->foreignKey($relIdA, $tableNameA, "id", new CascadeStrategy())
+      ->foreignKey($relIdB, $tableNameB, "id", new CascadeStrategy());
+
+    foreach ($dataColumns as $dataColumn) {
+      $query->addBool($dataColumn, false);
+    }
+
+    $query->unique(...$columns);
+    return $query;
+  }
+
+  public static function buildTableName(string ...$tables): string {
+    sort($tables);
+    return "NM_" . implode("_", $tables);
+  }
+
+  public function dependsOn(): array {
+    return [$this->handlerA->getTableName(), $this->handlerB->getTableName()];
+  }
+
+  public function getTableName(): string {
+    return self::buildTableName(...$this->dependsOn());
+  }
+
+  public function getCreateQueries(SQL $sql): array {
+    return [$this->getTableQuery($sql)];
+  }
+
+  public function getProperties(DatabaseEntityHandler $handler): array {
+    return $this->properties[$handler->getTableName()];
+  }
+
+  public function getOtherHandler(DatabaseEntityHandler $handler): DatabaseEntityHandler {
+    if ($handler === $this->handlerA) {
+      return $this->handlerB;
+    } else {
+      return $this->handlerA;
+    }
+  }
+}

Core/Objects/DatabaseEntity/Controller/Persistable.interface.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Core\Objects\DatabaseEntity\Controller;
+
+use Core\Driver\SQL\SQL;
+
+interface Persistable {
+
+  public function dependsOn(): array;
+  public function getTableName(): string;
+  public function getCreateQueries(SQL $sql): array;
+
+}

Core/Objects/DatabaseEntity/GpgKey.class.php

@@ -6,6 +6,7 @@ use Core\Driver\SQL\Expression\CurrentTimeStamp;
 use Core\Driver\SQL\SQL;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
 use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class GpgKey extends DatabaseEntity {
 

Core/Objects/DatabaseEntity/Group.class.php

@@ -3,14 +3,27 @@
 namespace Core\Objects\DatabaseEntity;
 
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class Group extends DatabaseEntity {
 
+  const ADMIN = 1;
+  const MODERATOR = 3;
+  const SUPPORT = 2;
+
+  const GROUPS = [
+    self::ADMIN => "Administrator",
+    self::MODERATOR => "Moderator",
+    self::SUPPORT => "Support",
+  ];
+
   #[MaxLength(32)] public string $name;
   #[MaxLength(10)] public string $color;
 
-  public function __construct(?int $id = null) {
+  public function __construct(?int $id, string $name, string $color) {
     parent::__construct($id);
+    $this->name = $name;
+    $this->color = $color;
   }
 
   public function jsonSerialize(): array {

Core/Objects/DatabaseEntity/Language.class.php

@@ -2,14 +2,17 @@
 
 namespace Core\Objects\DatabaseEntity {
 
-  use Core\Driver\SQL\SQL;
   use Core\Objects\DatabaseEntity\Attribute\MaxLength;
   use Core\Objects\DatabaseEntity\Attribute\Transient;
   use Core\Objects\lang\LanguageModule;
+  use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
   // TODO: language from cookie?
   class Language extends DatabaseEntity {
 
+    const AMERICAN_ENGLISH = 1;
+    const GERMAN_STANDARD = 2;
+
     const LANG_CODE_PATTERN = "/^[a-zA-Z]{2}_[a-zA-Z]{2}$/";
 
     #[MaxLength(5)] private string $code;

Core/Objects/DatabaseEntity/MailQueueItem.class.php

@@ -0,0 +1,124 @@
+<?php
+
+namespace Core\Objects\DatabaseEntity;
+
+use Core\API\Mail\Send;
+use Core\Driver\SQL\Expression\CurrentTimeStamp;
+use Core\Objects\Context;
+use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
+use Core\Objects\DatabaseEntity\Attribute\EnumArr;
+use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
+
+class MailQueueItem extends DatabaseEntity {
+
+  protected static array $entityLogConfig = [
+    "update" => true,
+    "delete" => true,
+    "insert" => true,
+    "lifetime" => 30
+  ];
+
+  const STATUS_WAITING = "waiting";
+  const STATUS_SUCCESS = "success";
+  const STATUS_ERROR = "error";
+  const STATUS_ITEMS = [self::STATUS_WAITING, self::STATUS_SUCCESS, self::STATUS_ERROR];
+
+  #[MaxLength(64)]
+  private string $from;
+
+  #[MaxLength(64)]
+  private string $to;
+
+  private string $subject;
+  private string $body;
+
+  #[MaxLength(64)]
+  private ?string $replyTo;
+
+  #[MaxLength(64)]
+  private ?string $replyName;
+
+  #[MaxLength(64)]
+  private ?string $gpgFingerprint;
+
+  #[EnumArr(self::STATUS_ITEMS)]
+  #[DefaultValue(self::STATUS_WAITING)]
+  private string $status;
+
+  #[DefaultValue(5)]
+  private int $retryCount;
+
+  #[DefaultValue(CurrentTimeStamp::class)]
+  private \DateTime $nextTry;
+
+  private ?string $errorMessage;
+
+  public function __construct(string $fromMail, string $toMail, string $subject, string $body,
+                              ?string $replyTo, ?string $replyName, ?string $gpgFingerprint) {
+    parent::__construct();
+    $this->from = $fromMail;
+    $this->to = $toMail;
+    $this->subject = $subject;
+    $this->body = $body;
+    $this->replyTo = $replyTo;
+    $this->replyName = $replyName;
+    $this->gpgFingerprint = $gpgFingerprint;
+    $this->retryCount =  5;
+    $this->nextTry = new \DateTime();
+    $this->errorMessage = null;
+    $this->status = self::STATUS_WAITING;
+  }
+
+  public function jsonSerialize(): array {
+    return [
+      "id" => $this->getId(),
+      "from" => $this->from,
+      "to" => $this->to,
+      "gpgFingerprint" => $this->gpgFingerprint,
+      "subject" => $this->subject,
+      "message" => $this->body,
+      "status" => $this->status,
+      "reply" => [
+        "to" => $this->replyTo,
+        "name" => $this->replyName,
+      ],
+      "retryCount" => $this->retryCount,
+      "nextTry" => $this->nextTry->getTimestamp(),
+      "errorMessage" => $this->errorMessage,
+    ];
+  }
+
+  public function send(Context $context): bool {
+
+    $args = [
+      "to" => $this->to,
+      "subject" => $this->subject,
+      "body" => $this->body,
+      "replyTo" => $this->replyTo,
+      "replyName" => $this->replyName,
+      "gpgFingerprint" => $this->gpgFingerprint,
+      "async" => false
+    ];
+
+    $req = new Send($context);
+    $success = $req->execute($args);
+    $this->errorMessage = $req->getLastError();
+
+    $delay = [0, 720, 360, 60, 30, 1];
+    $minutes = $delay[max(0, min(count($delay) - 1, $this->retryCount))];
+    if ($this->retryCount > 0) {
+      $this->retryCount--;
+      $this->nextTry = (new \DateTime())->modify("+$minutes minute");
+    } else if (!$success) {
+      $this->status = self::STATUS_ERROR;
+    }
+
+    if ($success) {
+      $this->status = self::STATUS_SUCCESS;
+    }
+
+    $this->save($context->getSQL());
+    return $success;
+  }
+}

Core/Objects/DatabaseEntity/News.class.php

@@ -6,6 +6,7 @@ use Core\API\Parameter\Parameter;
 use Core\Driver\SQL\Expression\CurrentTimeStamp;
 use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class News extends DatabaseEntity {
 
@@ -16,6 +17,7 @@ class News extends DatabaseEntity {
 
   public function __construct(?int $id = null) {
     parent::__construct($id);
+    $this->publishedAt = new \DateTime();
   }
 
   public function jsonSerialize(): array {

Core/Objects/DatabaseEntity/Notification.class.php

@@ -1,30 +0,0 @@
-<?php
-
-namespace Core\Objects\DatabaseEntity;
-
-use Core\API\Parameter\Parameter;
-use Core\Driver\SQL\Expression\CurrentTimeStamp;
-use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
-use Core\Objects\DatabaseEntity\Attribute\Enum;
-use Core\Objects\DatabaseEntity\Attribute\MaxLength;
-
-class Notification extends DatabaseEntity {
-
-  #[Enum('default', 'message', 'warning')] private string $type;
-  #[DefaultValue(CurrentTimeStamp::class)] private \DateTime $createdAt;
-  #[MaxLength(32)] public string $title;
-  #[MaxLength(256)] public string $message;
-
-  public function __construct(?int $id = null) {
-    parent::__construct($id);
-  }
-
-  public function jsonSerialize(): array {
-    return [
-      "id" => $this->getId(),
-      "createdAt" => $this->createdAt->format(Parameter::DATE_TIME_FORMAT),
-      "title" => $this->title,
-      "message" => $this->message
-    ];
-  }
-}

Core/Objects/DatabaseEntity/Session.class.php

@@ -10,6 +10,7 @@ use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
 use Core\Objects\DatabaseEntity\Attribute\Json;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
 use Core\Objects\DatabaseEntity\Attribute\Transient;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class Session extends DatabaseEntity {
 

Core/Objects/DatabaseEntity/SystemLog.class.php

@@ -7,6 +7,7 @@ use Core\Driver\SQL\Expression\CurrentTimeStamp;
 use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
 use Core\Objects\DatabaseEntity\Attribute\Enum;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class SystemLog extends DatabaseEntity {
 

Core/Objects/DatabaseEntity/TwoFactorToken.class.php

@@ -7,6 +7,7 @@ use Core\Objects\DatabaseEntity\Attribute\Enum;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
 use Core\Objects\TwoFactor\KeyBasedTwoFactorToken;
 use Core\Objects\TwoFactor\TimeBasedTwoFactorToken;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 abstract class TwoFactorToken extends DatabaseEntity {
 

Core/Objects/DatabaseEntity/User.class.php

@@ -2,14 +2,13 @@
 
 namespace Core\Objects\DatabaseEntity;
 
-use Core\Driver\SQL\Condition\Compare;
 use Core\Driver\SQL\Expression\CurrentTimeStamp;
-use Core\Driver\SQL\Join;
 use Core\Driver\SQL\SQL;
 use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
-use Core\Objects\DatabaseEntity\Attribute\Transient;
+use Core\Objects\DatabaseEntity\Attribute\Multiple;
 use Core\Objects\DatabaseEntity\Attribute\Unique;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class User extends DatabaseEntity {
 
@@ -20,30 +19,16 @@ class User extends DatabaseEntity {
   #[MaxLength(64)] public ?string $profilePicture;
   private ?\DateTime $lastOnline;
   #[DefaultValue(CurrentTimeStamp::class)] public \DateTime $registeredAt;
-  public bool $confirmed;
-  #[DefaultValue(1)] public Language $language;
+  #[DefaultValue(false)] public bool $confirmed;
+  #[DefaultValue(Language::AMERICAN_ENGLISH)] public Language $language;
   public ?GpgKey $gpgKey;
   private ?TwoFactorToken $twoFactorToken;
 
-  #[Transient] private array $groups;
+  #[Multiple(Group::class)]
+  public array $groups;
 
   public function __construct(?int $id = null) {
     parent::__construct($id);
-    $this->groups = [];
-  }
-
-  public function postFetch(SQL $sql, array $row) {
-    parent::postFetch($sql, $row);
-    $this->groups = [];
-
-    $groups = Group::findAllBuilder($sql)
-      ->addJoin(new Join("INNER", "UserGroup", "UserGroup.group_id", "Group.id"))
-      ->where(new Compare("UserGroup.user_id", $this->id))
-      ->execute();
-
-    if ($groups) {
-      $this->groups = $groups;
-    }
   }
 
   public function getUsername(): string {

Core/Objects/DatabaseEntity/UserToken.class.php

@@ -6,6 +6,7 @@ use Core\Driver\SQL\SQL;
 use Core\Objects\DatabaseEntity\Attribute\DefaultValue;
 use Core\Objects\DatabaseEntity\Attribute\EnumArr;
 use Core\Objects\DatabaseEntity\Attribute\MaxLength;
+use Core\Objects\DatabaseEntity\Controller\DatabaseEntity;
 
 class UserToken extends DatabaseEntity {