relations
[m6w6/pq-gateway] / lib / pq / Gateway / Table.php
index 79669115471813dd4bc3828f4089c4d7543ef4e3..af84e7f5eb59ed5c0e59c054a48c86bcb6f52620 100644 (file)
@@ -12,6 +12,11 @@ class Table
         */
        public static $defaultConnection;
        
+       /**
+        * @var callable
+        */
+       public static $defaultResolver;
+       
        /**
         * @var \pq\Connection
         */
@@ -36,21 +41,36 @@ class Table
         * @var \pq\Query\ExecutorInterface
         */
        protected $exec;
-
+       
        /**
-        * @var array
+        * @var \pq\Gateway\Table\Relations
         */
-       protected $dependents;
+       protected $relations;
        
+       /**
+        * @param string $table
+        * @return \pq\Gateway\Table
+        */
+       public static function resolve($table) {
+               if ($table instanceof Table) {
+                       return $table;
+               }
+               if (is_callable(static::$defaultResolver)) {
+                       if (($resolved = call_user_func(static::$defaultResolver, $table))) {
+                               return $resolved;
+                       }
+               }
+               return new Table($table);
+       }
+
        /**
         * @param string $name
         * @param \pq\Connection $conn
         * @param array $dependents
         */
-       function __construct($name, \pq\Connection $conn = null, array $dependents = array()) {
+       function __construct($name, \pq\Connection $conn = null) {
                $this->name = $name;
                $this->conn = $conn ?: static::$defaultConnection ?: new \pq\Connection;
-               $this->dependents = $dependents;
        }
        
        /**
@@ -113,6 +133,40 @@ class Table
                return $this->exec;
        }
        
+       /**
+        * Get foreign key relations
+        * @param string $to fkey
+        * @return \pq\Gateway\Table\Relations|stdClass
+        */
+       function getRelations($to = null) {
+               if (!isset($this->relations)) {
+                       $this->relations = new Table\Relations($this);
+               }
+               if (isset($to)) {
+                       if (!isset($this->relations->$to)) {
+                               return null;
+                       }
+                       return $this->relations->$to;
+               }
+               return $this->relations;
+       }
+       
+       /**
+        * Check whether a certain relation exists
+        * @param string $name
+        * @param string $table
+        * @return bool
+        */
+       function hasRelation($name, $table = null) {
+               if (!($rel = $this->getRelations($name))) {
+                       return false;
+               }
+               if (!isset($table)) {
+                       return true;
+               }
+               return isset($rel->$table);
+       }
+       
        /**
         * @return \pq\Connection
         */
@@ -133,6 +187,7 @@ class Table
         * @return mixed
         */
        protected function execute(QueryWriter $query) {
+               echo $query,"\n",json_encode($query->getParams()),"\n";
                return $this->getQueryExecutor()->execute($query, array($this, "onResult"));
        }
 
@@ -141,8 +196,8 @@ class Table
         * @param \pq\Result $result
         * @return mixed
         */
-       public function onResult(\pq\Result $result) {
-               if ($result->status != \pq\Result::TUPLES_OK) {
+       public function onResult(\pq\Result $result = null) {
+               if ($result && $result->status != \pq\Result::TUPLES_OK) {
                        return $result;
                }
                
@@ -181,40 +236,53 @@ class Table
        }
        
        /**
-        * Get the parent row of a row by foreign key
-        * @param \pq\Gateway\Row $dependent
+        * Get the child rows of a row by foreign key
+        * @param \pq\Gateway\Row $foreign
         * @param string $name optional fkey name
         * @param string $order
         * @param int $limit
         * @param int $offset
         * @return mixed
         */
-       function of(Row $dependent, $name = null, $order = null, $limit = 0, $offset = 0) {
-               if (!$name) {
-                       $name = $dependent->getTable()->getName();
+       function of(Row $foreign, $name = null, $order = null, $limit = 0, $offset = 0) {
+               // select * from $this where $this->$foreignColumn = $foreign->$referencedColumn
+               
+               if (!isset($name)) {
+                       $name = $this->getName();
+               }
+               
+               if (!$foreign->getTable()->hasRelation($name, $this->getName())) {
+                       return $this->onResult(null);
                }
-               return $this->find(array("{$name}_id=" => $dependent->id),
-                       $order, $limit, $offset);
+               $rel = $foreign->getTable()->getRelations($name)->{$this->getName()};
+               
+               return $this->find(
+                       array($rel->foreignColumn . "=" => $foreign->{$rel->referencedColumn}),
+                       $order, $limit, $offset
+               );
        }
        
        /**
-        * Get the child rows of a row by foreign key
+        * Get the parent rows of a row by foreign key
         * @param \pq\Gateway\Row $me
-        * @param string $dependent
+        * @param string $foreign
         * @param string $order
         * @param int $limit
         * @param int $offset
         * @return mixed
-        * @throws \LogicException
         */
-       function by(Row $me, $dependent, $order = null, $limit = 0, $offset = 0) {
-               if (!isset($this->dependents[$dependent])) {
-                       throw new \LogicException("Unknown dependent table $dependent");
+       function by(Row $me, $foreign, $order = null, $limit = 0, $offset = 0) {
+               // select * from $foreign where $foreign->$referencedColumn = $me->$foreignColumn
+               
+               if (!$this->hasRelation($foreign, $this->getName())) {
+                       return $this->onResult(null);
                }
+               $rel = $this->getRelations($foreign)->{$this->getName()};
                
-               $dependentClass = $this->dependents[$dependent];
-               $dependentModel = new $dependentClass($this->conn);
-               return $dependentModel->of($me, null, $order, $limit, $offset);
+               return static::resolve($rel->referencedTable)->find(
+                       array($rel->referencedColumn . "=" => $me->{$rel->foreignColumn}),
+                       $order, $limit, $offset
+               );
        }
 
        /**