Source of file Abstract_Query_Builder.php

<?php

/**

 * Query

 *

 * Free Query Builder / Database Abstraction Layer

 *

 * @package		Query

 * @author		Timothy J. Warren

 * @copyright	Copyright (c) 2012 - 2014

 * @link 		https://github.com/aviat4ion/Query

 * @license		http://philsturgeon.co.uk/code/dbad-license

 */

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

namespace Query;

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

/**

 * Abstract Class for internal implementation methods of the Query Builder

 * @package Query

 */

abstract class Abstract_Query_Builder {

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

	// ! Constants

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

	const KEY 	= 0;

	const VALUE = 1;

	const BOTH 	= 2;

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

	// ! SQL Clause Strings

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

	/**

	 * Compiled 'select' clause

	 * @var string

	 */

	protected $select_string = '';

	/**

	 * Compiled 'from' clause

	 * @var string

	 */

	protected $from_string;

	/**

	 * Compiled arguments for insert / update

	 * @var string

	 */

	protected $set_string;

	/**

	 * Order by clause

	 * @var string

	 */

	protected $order_string;

	/**

	 * Group by clause

	 * @var string

	 */

	protected $group_string;

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

	// ! SQL Clause Arrays

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

	/**

	 * Keys for insert/update statement

	 * @var array

	 */

	protected $set_array_keys = array();

	/**

	 * Key/val pairs for order by clause

	 * @var array

	 */

	protected $order_array = array();

	/**

	 * Key/val pairs for group by clause

	 * @var array

	 */

	protected $group_array = array();

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

	// ! Other Class vars

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

	/**

	 * Values to apply to prepared statements

	 * @var array

	 */

	protected $values = array();

	/**

	 * Values to apply to where clauses in prepared statements

	 * @var array

	 */

	protected $where_values = array();

	/**

	 * Value for limit string

	 * @var string

	 */

	protected $limit;

	/**

	 * Value for offset in limit string

	 * @var int

	 */

	protected $offset;

	/**

	 * Query component order mapping

	 * for complex select queries

	 *

	 * Format:

	 * array(

	 *		'type' => 'where',

	 *		'conjunction' => ' AND ',

	 *		'string' => 'k=?'

	 * )

	 *

	 * @var array

	 */

	protected $query_map = array();

	/**

	 * Map for having clause

	 * @var array

	 */

	protected $having_map;

	/**

	 * Convenience property for connection management

	 * @var string

	 */

	public $conn_name = "";

	/**

	 * List of queries executed

	 * @var array

	 */

	public $queries;

	/**

	 * Whether to do only an explain on the query

	 * @var bool

	 */

	protected $explain;

	/**

	 * The current database driver

	 * @var Driver_Interface

	 */

	public $db;

	/**

	 * Query parser class instance

	 * @var Query_Parser

	 */

	protected $parser;

	/**

	 * Alias to driver util class

	 * @var \Query\Driver\Abstract_Util

	 */

	protected $util;

	/**

	 * Alias to driver sql class

	 * @var \Query\Driver\SQL_Interface

	 */

	protected $sql;

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

	// Methods

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

	/**

	 * Set values in the class, with either an array or key value pair

	 *

	 * @param array $var

	 * @param mixed $key

	 * @param mixed $val

	 * @param int $val_type

	 * @return array

	 */

	protected function _mixed_set(&$var, $key, $val=NULL, $val_type=self::BOTH)

	{

		$arg = (is_scalar($key) && is_scalar($val))

			? array($key => $val)

			: $key;

		foreach($arg as $k => $v)

		{

			if (in_array($val_type, array(self::KEY, self::VALUE)))

			{

				$var[] = ($val_type === self::KEY)

					? $k

					: $v;

			}

			else

			{

				$var[$k] = $v;

			}

		}

		return $var;

	}

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

	/**

	 * Method to simplify select_ methods

	 *

	 * @param string $field

	 * @param string|bool $as

	 * @return string

	 */

	protected function _select($field, $as = FALSE)

	{

		// Escape the identifiers

		$field = $this->db->quote_ident($field);

		if ( ! is_string($as)) return $field;

		$as = $this->db->quote_ident($as);

		return "({$field}) AS {$as} ";

	}

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

	/**

	 * Helper function for returning sql strings

	 *

	 * @param string $type

	 * @param string $table

	 * @param bool $reset

	 * @return string

	 */

	protected function _get_compile($type, $table, $reset)

	{

		$sql = $this->_compile($type, $table);

		// Reset the query builder for the next query

		if ($reset) $this->reset_query();

		return $sql;

	}

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

	/**

	 * Simplify 'like' methods

	 *

	 * @param string $field

	 * @param mixed $val

	 * @param string $pos

	 * @param string $like

	 * @param string $conj

	 * @return Query_Builder

	 */

	protected function _like($field, $val, $pos, $like='LIKE', $conj='AND')

	{

		$field = $this->db->quote_ident($field);

		// Add the like string into the order map

		$like = $field. " {$like} ?";

		if ($pos == 'before')

		{

			$val = "%{$val}";

		}

		elseif ($pos == 'after')

		{

			$val = "{$val}%";

		}

		else

		{

			$val = "%{$val}%";

		}

		$conj = (empty($this->query_map)) ? ' WHERE ' : " {$conj} ";

		$this->_append_map($conj, $like, 'like');

		// Add to the values array

		$this->where_values[] = $val;

		return $this;

	}

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

	/**

	 * Simplify building having clauses

	 *

	 * @param mixed $key

	 * @param mixed $val

	 * @param string $conj

	 * @return Query_Builder

	 */

	protected function _having($key, $val=array(), $conj='AND')

	{

		$where = $this->_where($key, $val);

		// Create key/value placeholders

		foreach($where as $f => $val)

		{

			// Split each key by spaces, in case there

			// is an operator such as >, <, !=, etc.

			$f_array = explode(' ', trim($f));

			$item = $this->db->quote_ident($f_array[0]);

			// Simple key value, or an operator

			$item .= (count($f_array) === 1) ? '=?' : " {$f_array[1]} ?";

			// Put in the having map

			$this->having_map[] = array(

				'conjunction' => ( ! empty($this->having_map)) ? " {$conj} " : ' HAVING ',

				'string' => $item

			);

		}

		return $this;

	}

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

	/**

	 * Do all the repeditive stuff for where/having type methods

	 *

	 * @param mixed $key

	 * @param mixed $val

	 * @return array

	 */

	protected function _where($key, $val=array())

	{

		$where = array();

		$this->_mixed_set($where, $key, $val, self::BOTH);

		$this->_mixed_set($this->where_values, $key, $val, self::VALUE);

		return $where;

	}

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

	/**

	 * Simplify generating where string

	 *

	 * @param mixed $key

	 * @param mixed $val

	 * @param string $defaultConj

	 * @return Query_Builder

	 */

	protected function _where_string($key, $val=array(), $defaultConj='AND')

	{

		// Create key/value placeholders

		foreach($this->_where($key, $val) as $f => $val)

		{

			// Split each key by spaces, in case there

			// is an operator such as >, <, !=, etc.

			$f_array = explode(' ', trim($f));

			$item = $this->db->quote_ident($f_array[0]);

			// Simple key value, or an operator

			$item .= (count($f_array) === 1) ? '=?' : " {$f_array[1]} ?";

			$last_item = end($this->query_map);

			// Determine the correct conjunction

			$conjunctionList = array_pluck($this->query_map, 'conjunction');

			if (empty($this->query_map) || ( ! regex_in_array($conjunctionList, "/^ ?\n?WHERE/i")))

			{

				$conj = "\nWHERE ";

			}

			elseif ($last_item['type'] === 'group_start')

			{

				$conj = '';

			}

			else

			{

				$conj = " {$defaultConj} ";

			}

			$this->_append_map($conj, $item, 'where');

		}

		return $this;

	}

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

	/**

	 * Simplify where_in methods

	 *

	 * @param mixed $key

	 * @param mixed $val

	 * @param string $in - The (not) in fragment

	 * @param string $conj - The where in conjunction

	 * @return Query_Builder

	 */

	protected function _where_in($key, $val=array(), $in='IN', $conj='AND')

	{

		$key = $this->db->quote_ident($key);

		$params = array_fill(0, count($val), '?');

		foreach($val as $v)

		{

			$this->where_values[] = $v;

		}

		$conjunction = ( ! empty($this->query_map)) ? " {$conj} " : ' WHERE ';

		$str = $key . " {$in} (".implode(',', $params).') ';

		$this->_append_map($conjunction, $str, 'where_in');

		return $this;

	}

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

	/**

	 * Executes the compiled query

	 *

	 * @param string $type

	 * @param string $table

	 * @param string $sql

	 * @param array|null $vals

	 * @return \PDOStatement

	 */

	protected function _run($type, $table, $sql=NULL, $vals=NULL)

	{

		if (is_null($sql))

		{

			$sql = $this->_compile($type, $table);

		}

		if (is_null($vals))

		{

			$vals = array_merge($this->values, (array) $this->where_values);

		}

		$start_time = microtime(TRUE);

		$res = (empty($vals))

			? $this->db->query($sql)

			: $this->db->prepare_execute($sql, $vals);

		$end_time = microtime(TRUE);

		$total_time = number_format($end_time - $start_time, 5);

		// Add this query to the list of executed queries

		$this->_append_query($vals, $sql, $total_time);

		// Reset class state for next query

		$this->reset_query();

		return $res;

	}

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

	/**

	 * Add an additional set of mapping pairs to a internal map

	 *

	 * @param string $conjunction

	 * @param string $string

	 * @param string $type

	 * @return void

	 */

	protected function _append_map($conjunction = '', $string = '', $type = '')

	{

		array_push($this->query_map, array(

			'type' => $type,

			'conjunction' => $conjunction,

			'string' => $string

		));

	}

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

	/**

	 * Convert the prepared statement into readable sql

	 *

	 * @param array $vals

	 * @param string $sql

	 * @param string $total_time

	 * @return void

	 */

	protected function _append_query($vals, $sql, $total_time)

	{

		$evals = (is_array($vals)) ? $vals : array();

		$esql = str_replace('?', "%s", $sql);

		// Quote string values

		foreach($evals as &$v)

		{

			$v = ( ! is_numeric($v)) ? htmlentities($this->db->quote($v), ENT_NOQUOTES, 'utf-8')  : $v;

		}

		// Add the query onto the array of values to pass

		// as arguments to sprintf

		array_unshift($evals, $esql);

		// Add the interpreted query to the list of executed queries

		$this->queries[] = array(

			'time' => $total_time,

			'sql' => call_user_func_array('sprintf', $evals),

		);

		$this->queries['total_time'] += $total_time;

		// Set the last query to get rowcounts properly

		$this->db->set_last_query($sql);

	}

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

	/**

	 * Sub-method for generating sql strings

	 *

	 * @param string $type

	 * @param string $table

	 * @return string

	 */

	protected function _compile_type($type='', $table='')

	{

		if ($type === 'insert')

		{

			$param_count = count($this->set_array_keys);

			$params = array_fill(0, $param_count, '?');

			$sql = "INSERT INTO {$table} ("

				. implode(',', $this->set_array_keys)

				. ")\nVALUES (".implode(',', $params).')';

		}

		elseif ($type === 'update')

		{

			$sql = "UPDATE {$table}\nSET {$this->set_string}";

		}

		elseif ($type === 'delete')

		{

			$sql = "DELETE FROM {$table}";

		}

		else // GET queries

		{

			$sql = "SELECT * \nFROM {$this->from_string}";

			// Set the select string

			if ( ! empty($this->select_string))

			{

				// Replace the star with the selected fields

				$sql = str_replace('*', $this->select_string, $sql);

			}

		}

		return $sql;

	}

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

	/**

	 * String together the sql statements for sending to the db

	 *

	 * @param string $type

	 * @param string $table

	 * @return string

	 */

	protected function _compile($type='', $table='')

	{

		// Get the base clause for the query

		$sql = $this->_compile_type($type, $this->db->quote_table($table));

		$clauses = array(

			'query_map',

			'group_string',

			'order_string',

			'having_map',

		);

		// Set each type of subclause

		foreach($clauses as $clause)

		{

			$param = $this->$clause;

			if (is_array($param))

			{

				foreach($param as $q)

				{

					$sql .= $q['conjunction'] . $q['string'];

				}

			}

			else

			{

				$sql .= $param;

			}

		}

		// Set the limit via the class variables

		if (is_numeric($this->limit))

		{

			$sql = $this->sql->limit($sql, $this->limit, $this->offset);

		}

		// See if the query plan, rather than the

		// query data should be returned

		if ($this->explain === TRUE)

		{

			$sql = $this->sql->explain($sql);

		}

		return $sql;

	}

}

// End of abstract_query_builder.php