<?php

class FAModelDefinition {
	var $_pk = 'id';
	var $_table;

	var $_fks = array();
	var $_fields = array();
	var $_rels = array();
	var $_model;
	
	function FAModelDefinition(&$model) {
		$this->_model = &$model;
	}
	
	function &getFinder() {
		$finder = &$this->_model->getFinder($this->getName());
		
		return $finder;
	}
	
	function getForeignKey($table) {
		return $this->_fks[$table];
	}
	
	function getName() {
		return substr(get_class($this), 0, -10);
	}
	
	function getPrimaryKey() {
		return $this->_pk;
	}
	
	function getRecordClass() {
		$class = $this->getName() . 'Record';
		
		if (!class_exists($class)) {
			$class = 'FARecord';
		}
		
		return $class;
	}
	
	function getRecordSetClass() {
		$class = $this->getName() . 'Iterator';
		
		if (!class_exists($class)) {
			$class = 'FARecordSet';
		}
		
		return $class;
	}
	
	function &getRelation($field) {
		return $this->_rels[$field];
	}
	
	function getTable() {
		return $this->_table;
	}
	
	function hasField($field, $type, $regex = '//') {
		preg_match('~([a-z]+)(?:\(([0-9]+)\))?~i', $type, $matches);
		
		switch ($matches[1]) {
		case 'varchar':
		case 'char': {
				$type = 'string';
				break;
			}
		default: {
				$type = $matches[1];
			}
		}
		
		$this->_fields[$field] = array($type, $regex);
	}
	
	/**
	* @field	String	This is the key that is used to query the relation
	* @table	String	This is the table we will are searching
	* @join	String	The foreign key that holds the back reference to this table
	*/
	function hasMany($field, $table, $join) {
		$join = explode('.', $join);
		
		$fk_field = array_pop($join);
		$fk_model = array_pop($join)
			or $fk_model = $this->getName();
		
		$right = &$this->_model->getTable($table);
		
		$query = NULL;
		
		if ($fk_model == $right->getName()) {
			$right_table = $right->getTable();
			$right_key = $right->getForeignKey($this->getName());
			
			$select = "$right_table.*";
			$from = "$right_table";
			$where = "$right_table.$right_key=?";
			
			$query = &new FASelectQuery($select, $from, $where);
		}
		else {
			$middle = &$this->_model->getTable($fk_model);
			
			if ($right->getForeignKey($fk_model)) {
				$left_table = $this->getTable();
				$left_pk = $this->getPrimaryKey();
				$middle_table = $middle->getTable();
				$middle_fk = $middle->getForeignKey($this->getName());
				$middle_pk = $middle->getPrimaryKey();
				$right_table = $right->getTable();
				$right_fk = $right->getForeignKey($middle->getName());
							
				$select = "$right_table.*";
				$from = "$right_table";
				
				$query = &new FASelectQuery($select, $from);
				$query->addJoin($middle_table, "$middle_table.$middle_pk=$right_table.$right_fk");
				$query->addJoin($left_table, "$left_table.$left_pk=$middle_table.$middle_fk");
				$query->addWhere("$left_table.$left_pk=?");
			}
			elseif ($middle->getForeignKey($this->getName()) && $middle->getForeignKey($right->getName())) {
				$left_table = $this->getTable();
				$left_pk = $this->getPrimaryKey();
				$middle_table = $middle->getTable();
				$middle_fk_left = $middle->getForeignKey($this->getName());
				$middle_fk_right = $middle->getForeignKey($right->getName());
				$right_table = $right->getTable();
				$right_pk = $right->getPrimaryKey();
							
				$select = "$right_table.*";
				$from = "$right_table";
				
				$query = &new FASelectQuery($select, $from);
				$query->addJoin($middle_table, "$middle_table.$middle_fk_right=$right_table.$right_pk");
				$query->addJoin($left_table, "$left_table.$left_pk=$middle_table.$middle_fk_left");
				$query->addWhere("$left_table.$left_pk=?");
			}
		}
		
		if ($query != NULL) {
			$this->_rels[$field] = &new FAPluralRelation($query, $right->getFinder());
		}
	}
	
	function hasOne($field, $table, $join) {
		$join = explode('.', $join);
		
		$fk_field = array_pop($join);
		$fk_model = array_pop($join)
			or $fk_model = $this->getName();
		
		$right = &$this->_model->getTable($table);
		
		if ($fk_model == $this->getName()) {
			$this->_fks[$right->getName()] = $fk_field;
			
			$right_table = $right->getTable();
			$right_pk = $right->getPrimaryKey();
			$left_table = $this->getTable();
			$left_fk = $this->getForeignKey($right->getName());
			$left_pk = $this->getPrimaryKey();
			
			$select = "$right_table.*";
			$from = "$right_table";
			
			$query = &new FASelectQuery($select, $from);
			$query->addJoin($left_table, "$right_table.$right_pk=$left_table.$left_fk");
			$query->addWhere("$left_table.$left_pk=?");
		} else {
			$right_table = $right->getTable();
			$right_fk = $right->getForeignKey($this->getName());
			
			$select = "$right_table.*";
			$from = "$right_table";
			$where = "$right_table.$right_fk=?";
			
			$query = &new FASelectQuery($select, $from, $where);
		}
		
		if ($query != NULL) {
			$this->_rels[$field] = &new FASingularRelation($query, $right->getFinder());
		}
	}
	
	function init() {
	}
	
	function isRelation($field) {
		return isset($this->_rels[$field]);
	}
	
	function prepareSelect(&$query) {
	}
	
	function setPrimaryKey($field) {
		$this->_pk = $field;
	}
	
	function setTable($table) {
		$this->_table = $table;
	}
	
	function setTypes(&$data) {
		foreach ($data as $field => $value) {
			if (isset($this->_fields[$field])) {
				eval ('$data[$field] = (' . $this->_fields[$field][0] . ')$value;');
			}
		}
	}
	
	function validateField(&$field, $value) {
		if (!isset($this->_fields[$field])) {
			trigger_error("Field does not exist: " . $this->getTable() . ".$field", E_USER_NOTICE);
			
			// Not a fatal error, dev's should pick this up
			return TRUE;
		}
		
		$ret = TRUE;
		eval ('$value = (' . $this->_fields[$field][0] . ')$value;');
		
		if (!preg_match($this->_fields[$field][1], $value)) {
			$ret = FALSE;
		}
		
		return $ret;
	}
}

?>