<?php namespace CodeIgniter\Database;

/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2016, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package	CodeIgniter
 * @author	CodeIgniter Dev Team
 * @copyright	Copyright (c) 2014 - 2016, British Columbia Institute of Technology (http://bcit.ca/)
 * @license	http://opensource.org/licenses/MIT	MIT License
 * @link	http://codeigniter.com
 * @since	Version 3.0.0
 * @filesource
 */

/**
 * Interface ConnectionInterface
 *
 * @package CodeIgniter\Database
 */
interface ConnectionInterface
{
	/**
	 * Initializes the database connection/settings.
	 *
	 * @return mixed
	 */
	public function initialize();

	//--------------------------------------------------------------------

	/**
	 * Connect to the database.
	 *
	 * @param $persistent
	 * @return mixed
	 */
	public function connect($persistent = false);

	//--------------------------------------------------------------------

	/**
	 * Create a persistent database connection.
	 *
	 * @return mixed
	 */
	public function persistentConnect();

	//--------------------------------------------------------------------

	/**
	 * Keep or establish the connection if no queries have been sent for
	 * a length of time exceeding the server's idle timeout.
	 *
	 * @return mixed
	 */
	public function reconnect();

	//--------------------------------------------------------------------

	/**
	 * Returns the actual connection object. If both a 'read' and 'write'
	 * connection has been specified, you can pass either term in to
	 * get that connection. If you pass either alias in and only a single
	 * connection is present, it must return the sole connection.
	 *
	 * @param string|null $alias
	 *
	 * @return mixed
	 */
	public function getConnection(string $alias=null);

	//--------------------------------------------------------------------

	/**
	 * Select a specific database table to use.
	 *
	 * @param string $databaseName
	 *
	 * @return mixed
	 */
	public function setDatabase(string $databaseName);

	//--------------------------------------------------------------------

	/**
	 * Returns the name of the current database being used.
	 *
	 * @return string
	 */
	public function getDatabase(): string;

	//--------------------------------------------------------------------

	/**
	 * Returns the last error encountered by this connection.
	 *
	 * @return mixed
	 */
	public function getError();

	//--------------------------------------------------------------------

	/**
	 * The name of the platform in use (MySQLi, mssql, etc)
	 *
	 * @return mixed
	 */
	public function getPlatform();

	//--------------------------------------------------------------------

	/**
	 * Returns a string containing the version of the database being used.
	 *
	 * @return mixed
	 */
	public function getVersion();

	//--------------------------------------------------------------------

	/**
	 * Orchestrates a query against the database. Queries must use
	 * Database\Statement objects to store the query and build it.
	 * This method works with the cache.
	 *
	 * Should automatically handle different connections for read/write
	 * queries if needed.
	 *
	 * @param string $sql
	 * @param array  ...$binds
	 *
	 * @return mixed
	 */
	public function query(string $sql, $binds = null);

	//--------------------------------------------------------------------

	/**
	 * Performs a basic query against the database. No binding or caching
	 * is performed, nor are transactions handled. Simply takes a raw
	 * query string and returns the database-specific result id.
	 *
	 * @param string $sql
	 *
	 * @return mixed
	 */
	public function simpleQuery(string $sql);

	//--------------------------------------------------------------------

	/**
	 * Returns an instance of the query builder for this connection.
	 *
	 * @param string|array $tableName
	 *
	 * @return QueryBuilder
	 */
	public function table($tableName);

	//--------------------------------------------------------------------

	/**
	 * Returns the last query's statement object.
	 *
	 * @return mixed
	 */
	public function getLastQuery();

	//--------------------------------------------------------------------

	/**
	 * "Smart" Escaping
	 *
	 * Escapes data based on type.
	 * Sets boolean and null types.
	 *
	 * @param $str
	 *
	 * @return mixed
	 */
	public function escape($str);

	//--------------------------------------------------------------------

	/**
	 * Allows for custom calls to the database engine that are not
	 * supported through our database layer.
	 *
	 * @param string $functionName
	 * @param array  ...$params
	 *
	 * @return mixed
	 */
	public function callFunction(string $functionName, ...$params);

	//--------------------------------------------------------------------

}
