<?php
/**
 * KumbiaPHP web & app Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://wiki.kumbiaphp.com/Licencia
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to hide@address.com so we can send you a copy immediately.
 *
 * PDO SQLite Database Support
 * 
 * @category   Kumbia
 * @package    Db
 * @subpackage Adapters 
 * @copyright  Copyright (c) 2005-2009 Kumbia Team (http://www.kumbiaphp.com)
 * @license    http://wiki.kumbiaphp.com/Licencia     New BSD License
 */
class DbPdoSQLite extends DbPDO {

	/**
	 * Nombre de RBDM
	 */
	protected $db_rbdm = "sqlite";

	/**
	 * Tipo de Dato Integer
	 *
	 */
	const TYPE_INTEGER = "INTEGER";

	/**
	 * Tipo de Dato Date
	 *
	 */
	const TYPE_DATE = "DATE";

	/**
	 * Tipo de Dato Varchar
	 *
	 */
	const TYPE_VARCHAR = "VARCHAR";

	/**
	 * Tipo de Dato Decimal
	 *
	 */
	const TYPE_DECIMAL = "DECIMAL";

	/**
	 * Tipo de Dato Datetime
	 *
	 */
	const TYPE_DATETIME = "DATETIME";

	/**
	 * Tipo de Dato Char
	 *
	 */
	const TYPE_CHAR = "CHAR";

	/**
	 * Ejecuta acciones de incializacion del driver
	 *
	 */
	public function initialize(){

	}

	/**
	 * Verifica si una tabla existe o no
	 *
	 * @param string $table
	 * @return boolean
	 */
	public function table_exists($table, $schema=''){
		$table = strtolower($table);
		$num = $this->fetch_one("SELECT COUNT(*) FROM sqlite_master WHERE name = '$table'");
		return $num[0];
	}

	/**
	 * Devuelve un LIMIT valido para un SELECT del RBDM
	 *
	 * @param string $sql consulta sql
	 * @return string
	 */
	public function limit($sql){
		$params = Util::getParams(func_get_args());
		$sql_new = $sql;
	
		if(isset($params['limit']) && is_numeric($params['limit'])){
			$sql_new.=" LIMIT $params[limit]";
		}
		
		if(isset($params['offset']) && is_numeric($params['offset'])){
			$sql_new.=" OFFSET $params[offset]";
		}
		
		return $sql_new;
	}

	/**
	 * Borra una tabla de la base de datos
	 *
	 * @param string $table
	 * @return boolean
	 */
	public function drop_table($table, $if_exists=true){
		if($if_exists){
			return $this->query("DROP TABLE IF EXISTS $table");
		} else {
			return $this->query("DROP TABLE $table");
		}
	}

	/**
	 * Crea una tabla utilizando SQL nativo del RDBM
	 *
	 * TODO:
	 * - Falta que el parametro index funcione. Este debe listar indices compuestos multipes y unicos
	 * - Agregar el tipo de tabla que debe usarse (MySQL)
	 * - Soporte para campos autonumericos
	 * - Soporte para llaves foraneas
	 *
	 * @param string $table
	 * @param array $definition
	 * @return boolean
	 */
	public function create_table($table, $definition, $index=array()){
		$create_sql = "CREATE TABLE $table (";
		if(!is_array($definition)){
			new KumbiaException("Definici&oacute;n invalida para crear la tabla '$table'");
			return false;
		}
		$create_lines = array();
		$index = array();
		$unique_index = array();
		$primary = array();
		$not_null = "";
		$size = "";
		foreach($definition as $field => $field_def){
			if(isset($field_def['not_null'])){
				$not_null = $field_def['not_null'] ? 'NOT NULL' : '';
			} else {
				$not_null = "";
			}
			if(isset($field_def['size'])){
				$size = $field_def['size'] ? '('.$field_def['size'].')' : '';
			} else {
				$size = "";
			}
			if(isset($field_def['index'])){
				if($field_def['index']){
					$index[] = "INDEX($field)";
				}
			}
			if(isset($field_def['unique_index'])){
				if($field_def['unique_index']){
					$index[] = "UNIQUE($field)";
				}
			}
			if(isset($field_def['primary'])){
				if($field_def['primary']){
					$primary[] = "$field";
				}
			}
			if(isset($field_def['auto'])){
				if($field_def['auto']){
					$not_null = "";
				}
			}
			if(isset($field_def['extra'])){
				$extra = $field_def['extra'];
			} else {
				$extra = "";
			}
			$create_lines[] = "$field ".$field_def['type'].$size.' '.$not_null.' '.$extra;
		}
		$create_sql.= join(',', $create_lines);
		$last_lines = array();
		if(count($primary)){
			$last_lines[] = 'PRIMARY KEY('.join(",", $primary).')';
		}
		if(count($index)){
			$last_lines[] = join(',', $index);
		}
		if(count($unique_index)){
			$last_lines[] = join(',', $unique_index);
		}
		if(count($last_lines)){
			$create_sql.= ','.join(',', $last_lines).')';
		}
		return $this->exec($create_sql);

	}

	/**
	 * Listar las tablas en la base de datos
	 *
	 * @return array
	 */
	public function list_tables(){
		return $this->fetch_all("SELECT name FROM sqlite_master WHERE type='table' ".
							    "UNION ALL SELECT name FROM sqlite_temp_master ".
							    "WHERE type='table' ORDER BY name");
	}

	/**
	 * Listar los campos de una tabla
	 *
	 * @param string $table
	 * @return array
	 */
	public function describe_table($table, $schema=''){
		$fields = array();
		if(!$schema){
			$results = $this->fetch_all("PRAGMA table_info($table)", DB::DB_ASSOC);
		} else {
			$results = $this->fetch_all("PRAGMA table_info($schema.$table)", DB::DB_ASSOC);
		}
		foreach($results as $field){
			$fields[] = array(
				"Field" => $field["name"],
				"Type" => $field["type"],
				"Null" => $field["notnull"] == 99 ? "YES" : "NO",
				"Key" => $field['pk'] == 1 ? "PRI" : ""
			);
		}
		return $fields;
	}

}