1: <?php
 2: 
 3: namespace Alchemy\core\schema;
 4: 
 5: 
 6: /**
 7:  * Class for representing a foreign key constraint in SQL
 8:  */
 9: class ForeignKey extends Index {
10:     protected static $default_args = array(
11:         array(), array(),
12:         'ondelete' => 'restrict',
13:         'onupdate' => 'restrict');
14: 
15:     protected $sources;
16: 
17: 
18:     /**
19:      * Get the table the key references
20:      *
21:      * @return Table
22:      */
23:     public function getSourceTable() {
24:         $this->resolve();
25:         return $this->sources[0]->getTable();
26:     }
27: 
28: 
29:     /**
30:      * Get the columns the key references
31:      *
32:      * @return array
33:      */
34:     public function listSources() {
35:         $this->resolve();
36:         return $this->sources;
37:     }
38: 
39: 
40:     public function getNameMap() {
41:         $this->resolve();
42: 
43:         $map = array();
44:         foreach($this->sources as $k => $source) {
45:             $map[$source->getName()] = $this->columns[$k]->getName();
46:         }
47: 
48:         return $map;
49:     }
50: 
51: 
52:     protected function resolve() {
53:         if ($this->columns) return;
54: 
55:         parent::resolve();
56: 
57:         if (!isset($this->args[1]) || count($this->args[0]) != count($this->args[1])) {
58:             throw new \Exception("ForeignKey received the wrong number of sources.");
59:         }
60: 
61:         foreach($this->args[1] as $source) {
62:             $this->sources[] = is_string($source)
63:                 ? Column::find($source, $this->table)
64:                 : $source;
65:         }
66:     }
67: }
68: