<?php
/* $Id$ */
namespace Mammut\DB\MSSQL;

(defined('MAMMUT') && (basename(__FILE__) != basename($_SERVER['PHP_SELF']))) or die('ACCESS DENIED');

use Mammut\Exception\ImplementationException;
use Mammut\DB\DB;
use Mammut\DB\Model\TableInfo;
use Mammut\DB\Model\ColumnInfo;

/**
 * Table on linked servers
 *
 * @author Stefan Daurer <s.daurer@q-spot.org>
 * @package Mammut\DB\Adapter\MSSQL
 */
class LinkedSrvTable extends Table {
	private $info = NULL; // cache

	public function __construct(MSSQL &$dbbase, $server, $db, $table, $prefix = false) {
	}

	/**
	 *
	 * @param $db DB
	 *        	instance
	 * @param $tableName string
	 *        	name
	 * @return TableInfo info object
	 */
	public function getInfo() {
		if(is_object($this->info))
			return $this->info;
		$table = $this->getName();
		$info = new TableInfo($table);
		
		$result = $this->db->query("SELECT * FROM information_schema.columns WHERE table_name = '{$table}'");
		while($row = $result->fetchArray()) {
			$name = $row['COLUMN_NAME'];
			$type = '';
			$size = -1;
			$param = array();
			$charset = NULL;
			$collate = NULL;
			
			if(preg_match('#^([a-zA-Z]+)#', $row['DATA_TYPE'], $match)) {
				if($row['IS_NULLABLE'] == 'YES')
					$param[] = 'null';
				
				switch(strtolower(trim($match[1]))) {
					case 'tinyint':
						$type = ColumnInfo::TYPE_TINY;
					break;
					case 'smallint':
						$type = ColumnInfo::TYPE_SHORT;
					break;
					case 'int':
						$type = ColumnInfo::TYPE_INT;
					break;
					case 'bigint':
						$type = ColumnInfo::TYPE_LONG;
					break;
					case 'float':
						$type = ColumnInfo::TYPE_FLOAT;
					break;
					case 'char':
						$type = ColumnInfo::TYPE_CHAR;
						$size = (int) $row['CHARACTER_MAXIMUM_LENGTH'];
					break;
					case 'varchar':
						$type = ColumnInfo::TYPE_VCHAR;
						$size = (int) $row['CHARACTER_MAXIMUM_LENGTH'];
					break;
					case 'date':
						$type = ColumnInfo::TYPE_DATE;
					break;
					case 'datetime':
						$type = ColumnInfo::TYPE_DATETIME;
					break;
					case 'bit':
						$type = ColumnInfo::TYPE_BOOLEAN;
					break;
					case 'text':
						$type = ColumnInfo::TYPE_TEXT;
					break;
					case 'varbinary':
						$type = ColumnInfo::TYPE_BINARY;
					break;
					case 'image':
						$type = ColumnInfo::TYPE_BLOB;
					break;
				}
			}
			$addinfo = $this->db->getArrayList("SELECT objtype, objname, name, CAST(value AS nvarchar(255)) AS value FROM fn_listextendedproperty (NULL, 'schema', 'dbo', 'table', '{$table}', 'column', '{$name}')");
			foreach($addinfo as $add) {
				if($add['name'] == 'MFType') {
					if(preg_match('!enum\((.*)\)!', $add['value'], $match)) {
						$type = ColumnInfo::TYPE_ENUM;
						$param[] = 'values(' . $match[1] . ')';
						$size = -1;
					}
				}
			}
			
			$cinfo = new ColumnInfo($name, $type, $size, $param, $charset, $collate);
			$info->addColumn($cinfo);
		}
		$this->info = $info;
		return $info;
	}

	public function addColumn(ColumnInfo $info, $after = NULL) {
		$colSQL = MSSQLUtil::fieldDefSQL($this->db, $info);
		$sql = "ALTER TABLE " . $this->db->escapeTableName($this->getName()) . " ADD COLUMN " . $colSQL;
		if(is_int($after)) {
			if($after < 0)
				$sql .= ' FIRST';
			else {
				$tinfo = $this->getInfo();
				$colName = $tinfo->getColumn($after)->getName();
				$sql .= ' AFTER ' . $this->db->escapeColumnName($colName);
				unset($colName, $tinfo);
			}
		}
		$this->info = NULL;
		$this->db->query($sql);
	}

	public function alterColumn($column, ColumnInfo $newInfo) {
		throw new ImplementationException('not implemented');
	}

	public function removeColumn($column) {
		$this->info = NULL;
		if($column instanceof ColumnInfo)
			$column = $column->getName();
		$this->db->query("ALTER TABLE " . $this->db->escapeTableName($this->getName()) . " DROP COLUMN " . $column);
	}
}