<?php
	namespace Mocha\Oms;

	use Mocha\Core\InstanceKey;
	use Mocha\Core\InstanceReference;

	class MySQLDatabaseOms extends DatabaseOms
	{
		public \PDO $PDO;

		public function __construct($hostname, $port, $databasename, $username, $password)
		{
			$this->PDO = new \PDO("mysql:host=" . $hostname . ";port=" . $port . ";dbname=" . $databasename, $username, $password);
		}

		public function getDbId($instRef)
		{
			if ($instRef == null)
				return 0;

			return $instRef->DatabaseId;
		}

		public function getInstanceByGlobalIdentifier(string $globalIdentifier) : ?InstanceReference
		{
			$query = "CALL mocha_get_instance_by_global_identifier(:global_identifier)";
			$stmt = $this->PDO->prepare($query);
			$result = $stmt->execute(array
			(
				"global_identifier" => $globalIdentifier
			));

			if ($result === false)
				return null;

			$values = $stmt->fetchAll();
			if (count($values) == 0)
				return null;

			$dbid = $values[0]["id"];
			$class_id = $values[0]["class_id"];
			$inst_id = $values[0]["inst_id"];
			$global_id = $values[0]["global_identifier"];
			
			$ir = new InstanceReference();
			$ir->DatabaseId = $dbid;
			$ir->GlobalIdentifier = $global_id;
			$ir->InstanceKey = new InstanceKey($class_id, $inst_id);
			return $ir;
		}
		
		public function getRelatedInstances(InstanceReference $sourceInstance, InstanceReference $relationshipInstance, \DateTime $effectiveDate = null) : ?array
		{
			$dt = null;
			if ($effectiveDate !== null)
			{
				$dt = $effectiveDate->format("Y-m-d");
			}
			$query = "CALL mocha_get_related_instances(:src_inst_id, :rel_inst_id, :eff_date)";
			$stmt = $this->PDO->prepare($query);
			$result = $stmt->execute(array
			(
				"src_inst_id" => $this->getDbId($sourceInstance),
				"rel_inst_id" => $this->getDbId($relationshipInstance),
				"eff_date" => $dt
			));
			
			if ($result === false)
			{
				return null;
			}

			$values = $stmt->fetchAll();
			if (count($values) >= 0)
			{
				$ret = array();
				foreach ($values as $value)
				{
					$retval = new InstanceReference();
					$retval->DatabaseId = $value["id"];
					$retval->InstanceKey = new InstanceKey($value["class_id"], $value["inst_id"]);
					$retval->GlobalIdentifier = $value["global_identifier"];
					$ret[] = $retval;
				}
				return $ret;
			}
			return [];
		}

		public function getAttributeValue($sourceInstance, $attributeInstance, $defaultValue = null, $effectiveDate = null) : ?string
		{
			$query = "CALL mocha_get_attribute_value(:src_inst_id, :attr_inst_id, :eff_date)";
			$stmt = $this->PDO->prepare($query);
			$result = $stmt->execute(array
			(
				"src_inst_id" => $this->getDbId($sourceInstance),
				"attr_inst_id" => $this->getDbId($attributeInstance),
				"eff_date" => $effectiveDate
			));
			
			if ($result === false)
			{
				return $defaultValue;
			}

			$values = $stmt->fetchAll();
			if (count($values) >= 0)
			{
				$value = $values[0]["att_value"];
				return $value;
			}
			return $defaultValue;
		}
	}
?>