<?php

abstract class Qs_Sys_Validate_Unique extends Zend_Validate_Abstract
{
    const NOT_UNIQUE = 'notUnique';
    protected $_table;
    protected $_column;
    protected $_where = array();
    protected $_current;
    protected $_messageTemplates = array(
        self::NOT_UNIQUE    =>    'Field value must be unique',
    );
    
    public function __construct($table, $column, $current = null, $options = array())
    {
        $this->_table = $table;
        $this->_column = $column;
        $this->_current = $current;
        if (is_array($options) && !empty($options)) {
            $this->setOptions($options);
        }
    }
    
    public function setOptions($options)
    {
        if (isset($options['options'])) {
            unset($options['options']);
        }
        foreach ($options as $key => $value) {
            $method = 'set' . ucfirst($key);
            if (method_exists($this, $method)) {
                // Setter exists; use it
                $this->$method($value);
            } 
        }
    }
    
    public function setWhere($where)
    {
        $this->_where = (array)$where;
    }
    
    public function getWhere()
    {
        return $this->_where;
    }
   
    public function setMethod($method)
    {
        if (!method_exists($this->dataObj, $method)) {
            throw new Zend_Validate_Exception('Unknown method "' .$method . '"');
        } 
    }
    
    public function getMethod()
    {
        if (null === $this->_method) {
            $this->setMethod('isUnique');
        }
        return $this->_method;
    }

    public function isValid($value, $context = null)
    {
        $value = (string) $value;
        $this->_setValue($value);
        $db = $this->_table->getAdapter();
        $where = $this->getWhere();
        $where[] = $db->quoteInto($this->_column . ' = ?', $value);
        if (isset($this->_current)) {
            $current = (array) $this->_current;
            $info = $this->_table->info();
            foreach ($info['primary'] as $key => $column) {
                $where[] = $db->quoteInto($column . ' <> ?', $current[$key - 1]);
            }
        }
        $rowset = $this->_table->fetchAll($where);
        if ($rowset->count()) {
            $this->_error(self::NOT_UNIQUE);
            return false;
        }
        return true;
    }
}