Core v2.3, N:M Relations

2022-11-20 17:13:53 +01:00
parent b5b8f9b856
commit 303a5b69b5
41 changed files with 962 additions and 1047 deletions
--- a/Core/Objects/DatabaseEntity/Controller/NMRelation.class.php
+++ b/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;
+    }
+  }
+}