Implement Fairteiler gateway

Refs https://gitlab.com/foodsharing-dev/issues0/issues/344

Still needs a bit of testing, otherwise I'm quite happy with it.

src/Modules/Core/Database.php

@@ -28,12 +28,125 @@ class Database
 		return $this->preparedQuery($query, $params)->fetchColumn(0);
 	}
 
+	public function execute($query, $params = [])
+	{
+		return $this->preparedQuery($query, $params)->rowCount();
+	}
+
+	public function insert($table, array $data)
+	{
+		$columns = array_map(
+			[$this, 'getQuotedName'],
+			array_keys($data)
+		);
+
+		$query = sprintf(
+			'INSERT INTO %s (%s) VALUES (%s)',
+			$this->getQuotedName($table),
+			implode(', ', $columns),
+			implode(', ', array_fill(0, count($data), '?'))
+		);
+
+		return $this->execute($query, array_values($data));
+	}
+
+	public function update($table, array $data, array $criteria = [])
+	{
+		if (empty($data)) {
+			throw new \InvalidArgumentException(
+				"Query update can't be prepared without data."
+			);
+		}
+
+		$set = [];
+		foreach ($data as $column => $value) {
+			$set[] = $this->getQuotedName($column) . " = ?";
+		}
+
+		$where = $this->generateWhereClause($criteria);
+
+		$query = sprintf('UPDATE %s SET %s %s', $this->getQuotedName($table), implode(', ', $set), $where);
+
+		$params = array_merge(array_values($data), array_values($criteria));
+		return $this->execute($query, $params);
+	}
+
+	public function delete($table, array $criteria)
+	{
+		$where = $this->generateWhereClause($criteria);
+
+		$query = 'DELETE FROM ' . $this->getQuotedName($table) . ' ' . $where;
+		return $this->execute($query, array_values($criteria));
+	}
+
+	// === private functions ===
+
 	private function preparedQuery($query, $params)
 	{
 		$statement = $this->pdo->prepare($query);
+		if (!$statement) {
+			throw new \Exception("Query '$query' can't be prepared.");
+		}
+
+		$i = 0;
+		foreach ($params as $value) {
+			$i++;
+			if (is_bool($value)) {
+				$type = \PDO::PARAM_BOOL;
+			} elseif (is_int($value)) {
+				$type = \PDO::PARAM_INT;
+			} else {
+				$type = \PDO::PARAM_STR;
+			}
+			$statement->bindValue($i, $value, $type);
+		}
+
 		$statement->setFetchMode(PDO::FETCH_ASSOC);
-		$statement->execute($params);
+		$statement->execute();
 
 		return $statement;
 	}
+
+	private function getQuotedName($name)
+	{
+		return '"' . str_replace('.', '"."', $name) . '"';
+	}
+
+	private function generateWhereClause(array &$criteria)
+	{
+		if (empty($criteria)) {
+			return '';
+		}
+
+		$operands = $this->getSupportedOperators();
+
+		$params = [];
+		foreach ($criteria as $k => $v) {
+			if ($v === null) {
+				$params[] = $this->getQuotedName($k) . " IS NULL ";
+				unset($criteria[$k]);
+				continue;
+			}
+
+			$hasOperand = false; // search for equals - no additional operand given
+
+			foreach ($operands as $operand) {
+				if (!stripos($k, " $operand") > 0) {
+					continue;
+				}
+
+				$hasOperand = true;
+				$k = str_ireplace(" $operand", '', $k);
+				$operand = strtoupper($operand);
+				$params[] = $this->getQuotedName($k) . " $operand ? ";
+				break;
+			}
+
+			if (!$hasOperand) {
+				$params[] = $this->getQuotedName($k) . " = ? ";
+			}
+		}
+
+		return 'WHERE ' . implode('AND ', $params);
+	}
 }