<?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
 */

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

/**
 * Interface defining the Query Builder class
 *
 * @package Query
 * @subpackage Query
 */
interface Query_Builder_Interface {

	// --------------------------------------------------------------------------
	// ! Select Queries
	// --------------------------------------------------------------------------

	/**
	 * Specifies rows to select in a query
	 *
	 * @param string $fields
	 * @return $this
	 */
	public function select($fields);

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

	/**
	 * Selects the maximum value of a field from a query
	 *
	 * @param string $field
	 * @param string $as
	 * @return $this
	 */
	public function select_max($field, $as=FALSE);

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

	/**
	 * Selects the minimum value of a field from a query
	 *
	 * @param string $field
	 * @param string $as
	 * @return $this
	 */
	public function select_min($field, $as=FALSE);

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

	/**
	 * Selects the average value of a field from a query
	 *
	 * @param string $field
	 * @param string $as
	 * @return $this
	 */
	public function select_avg($field, $as=FALSE);

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

	/**
	 * Selects the sum of a field from a query
	 *
	 * @param string $field
	 * @param string $as
	 * @return $this
	 */
	public function select_sum($field, $as=FALSE);

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

	/**
	 * Adds the 'distinct' keyword to a query
	 *
	 * @return $this
	 */
	public function distinct();

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

	/**
	 * Shows the query plan for the query
	 *
	 * @return $this
	 */
	public function explain();

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

	/**
	 * Specify the database table to select from
	 *
	 * @param string $tblname
	 * @return $this
	 */
	public function from($tblname);

	// --------------------------------------------------------------------------
	// ! 'Like' methods
	// --------------------------------------------------------------------------

	/**
	 * Creates a Like clause in the sql statement
	 *
	 * @param string $field
	 * @param mixed $val
	 * @param string $pos
	 * @return $this
	 */
	public function like($field, $val, $pos='both');

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

	/**
	 * Generates an OR Like clause
	 *
	 * @param string $field
	 * @param mixed $val
	 * @param string $pos
	 * @return $this
	 */
	public function or_like($field, $val, $pos='both');

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

	/**
	 * Generates a NOT LIKE clause
	 *
	 * @param string $field
	 * @param mixed $val
	 * @param string $pos
	 * @return $this
	 */
	public function not_like($field, $val, $pos='both');

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

	/**
	 * Generates a OR NOT LIKE clause
	 *
	 * @param string $field
	 * @param mixed $val
	 * @param string $pos
	 * @return $this
	 */
	public function or_not_like($field, $val, $pos='both');

	// --------------------------------------------------------------------------
	// ! Having methods
	// --------------------------------------------------------------------------

	/**
	 * Generates a 'Having' clause
	 *
	 * @param mixed $key
	 * @param mixed $val
	 * @return $this
	 */
	public function having($key, $val=array());

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

	/**
	 * Generates a 'Having' clause prefixed with 'OR'
	 *
	 * @param mixed $key
	 * @param mixed $val
	 * @return $this
	 */
	public function or_having($key, $val=array());

	// --------------------------------------------------------------------------
	// ! 'Where' methods
	// --------------------------------------------------------------------------

	/**
	 * Specify condition(s) in the where clause of a query
	 * Note: this function works with key / value, or a
	 * passed array with key / value pairs
	 *
	 * @param mixed $key
	 * @param mixed $val
	 * @param bool $escape
	 * @return $this
	 */
	public function where($key, $val=array(), $escape = NULL);

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

	/**
	 * Where clause prefixed with "OR"
	 *
	 * @param string $key
	 * @param mixed $val
	 * @return $this
	 */
	public function or_where($key, $val=array());

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

	/**
	 * Where clause with 'IN' statement
	 *
	 * @param mixed $field
	 * @param mixed $val
	 * @return $this
	 */
	public function where_in($field, $val=array());

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

	/**
	 * Where in statement prefixed with "or"
	 *
	 * @param string $field
	 * @param mixed $val
	 * @return $this
	 */
	public function or_where_in($field, $val=array());

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

	/**
	 * WHERE NOT IN (FOO) clause
	 *
	 * @param string $field
	 * @param mixed $val
	 * @return $this
	 */
	public function where_not_in($field, $val=array());

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

	/**
	 * OR WHERE NOT IN (FOO) clause
	 *
	 * @param string $field
	 * @param mixed $val
	 * @return $this
	 */
	public function or_where_not_in($field, $val=array());

	// --------------------------------------------------------------------------
	// ! Other Query Modifier methods
	// --------------------------------------------------------------------------

	/**
	 * Sets values for inserts / updates / deletes
	 *
	 * @param mixed $key
	 * @param mixed $val
	 * @return $this
	 */
	public function set($key, $val = NULL);

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

	/**
	 * Creates a join phrase in a compiled query
	 *
	 * @param string $table
	 * @param string $condition
	 * @param string $type
	 * @return $this
	 */
	public function join($table, $condition, $type='');

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

	/**
	 * Group the results by the selected field(s)
	 *
	 * @param mixed $field
	 * @return $this
	 */
	public function group_by($field);

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

	/**
	 * Order the results by the selected field(s)
	 *
	 * @param string $field
	 * @param string $type
	 * @return $this
	 */
	public function order_by($field, $type="");

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

	/**
	 * Set a limit on the current sql statement
	 *
	 * @param int $limit
	 * @param int $offset
	 * @return string
	 */
	public function limit($limit, $offset=FALSE);

	// --------------------------------------------------------------------------
	// ! Query Grouping Methods
	// --------------------------------------------------------------------------

	/**
	 * Adds a paren to the current query for query grouping
	 *
	 * @return $this
	 */
	public function group_start();

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

	/**
	 * Adds a paren to the current query for query grouping,
	 * prefixed with 'OR'
	 *
	 * @return $this
	 */
	public function or_group_start();

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

	/**
	 * Adds a paren to the current query for query grouping,
	 * prefixed with 'OR NOT'
	 *
	 * @return $this
	 */
	public function or_not_group_start();

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

	/**
	 * Ends a query group
	 *
	 * @return $this
	 */
	public function group_end();

	// --------------------------------------------------------------------------
	// ! Query execution methods
	// --------------------------------------------------------------------------

	/**
	 * Select and retrieve all records from the current table, and/or
	 * execute current compiled query
	 *
	 * @param $table
	 * @param int $limit
	 * @param int $offset
	 * @return PDOStatement
	 */
	public function get($table='', $limit=FALSE, $offset=FALSE);

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

	/**
	 * Convience method for get() with a where clause
	 *
	 * @param string $table
	 * @param array $where
	 * @param int $limit
	 * @param int $offset
	 * @return PDOStatement
	 */
	public function get_where($table, $where=array(), $limit=FALSE, $offset=FALSE);

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

	/**
	 * Retreive the number of rows in the selected table
	 *
	 * @param string $table
	 * @return int
	 */
	public function count_all($table);

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

	/**
	 * Retrieve the number of results for the generated query - used
	 * in place of the get() method
	 *
	 * @param string $table
	 * @return int
	 */
	public function count_all_results($table='');

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

	/**
	 * Creates an insert clause, and executes it
	 *
	 * @param string $table
	 * @param mixed $data
	 * @return PDOStatement
	 */
	public function insert($table, $data=array());

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

	/**
	 * Creates and executes a batch insertion query
	 *
	 * @param string $table
	 * @param array $data
	 * @return PDOStatement
	 */
	public function insert_batch($table, $data=array());

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

	/**
	 * Creates an update clause, and executes it
	 *
	 * @param string $table
	 * @param mixed $data
	 * @return PDOStatement
	 */
	public function update($table, $data=array());

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

	/**
	 * Deletes data from a table
	 *
	 * @param string $table
	 * @param mixed $where
	 * @return PDOStatement
	 */
	public function delete($table, $where='');

	// --------------------------------------------------------------------------
	// ! SQL Returning Methods
	// --------------------------------------------------------------------------

	/**
	 * Returns the generated 'select' sql query
	 *
	 * @param string $table
	 * @param bool $reset
	 * @return string
	 */
	public function get_compiled_select($table='', $reset=TRUE);

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

	/**
	 * Returns the generated 'insert' sql query
	 *
	 * @param string $table
	 * @param bool $reset
	 * @return string
	 */
	public function get_compiled_insert($table, $reset=TRUE);

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

	/**
	 * Returns the generated 'update' sql query
	 *
	 * @param string $table
	 * @param bool $reset
	 * @return string
	 */
	public function get_compiled_update($table='', $reset=TRUE);

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

	/**
	 * Returns the generated 'delete' sql query
	 *
	 * @param string $table
	 * @param bool $reset
	 * @return string
	 */
	public function get_compiled_delete($table="", $reset=TRUE);

	// --------------------------------------------------------------------------
	// ! Miscellaneous Methods
	// --------------------------------------------------------------------------

	/**
	 * Clear out the class variables, so the next query can be run
	 *
	 * @return void
	 */
	public function reset_query();
}

// End of query_builder_interface.php