<?php
/**
 * Created by PhpStorm.
 * User: lucas
 * Date: 30/08/16
 * Time: 17:26
 */

namespace database\core\PDOWrapper;


class PDOWrapper extends \PDO
{
	private $statements = [];
	private $stacking = false;

    public function __construct(String $dsn, String $username, String $passwd, array $options = [])
    {
        parent::__construct($dsn, $username, $passwd, $options);
    }

    public function prepare($statement, $options = [])
    {
        if($this->stacking){
            return new PDOStatementWrapper($statement, $this);
        }else{
			parent::setAttribute(\PDO::ATTR_EMULATE_PREPARES, true);
        	return parent::prepare($statement, $options);

        }
    }

    public function enableStacking(){
    	$this->stacking = true;
	}

	public function stackStatement(PDOStatementWrapper $st){
		array_push($this->statements,$st);
	}

	public function executeStack(){
		//init the statements and the generator of number
		$finalStatement = '';
		$finalExecute = [];
		$i = 0;

		//for each request stacked
		foreach ($this->statements as $request){
			$statement = $request->getStatement();

			// we have to modify the parameters index at the same time that we modify the request, so we use static class attribute
			$tempParametes = $request->getParameters();

			//find the given pattern in the request, then call our function and replace the matched string by the return value of our function
			$finalStatement .= rtrim(preg_replace_callback("/(:[a-z_\-0-9]*)/is",function($matches) use (&$i,&$tempParametes){
					//get next number
					$i++;

					//delete the ':' at the beginning of the string
					$tempKey = ltrim($matches[0],':');

					//copy the parameter with the modified index
					$tempParametes[$tempKey.$i] = $tempParametes[$tempKey];

					//delete the old index
					unset($tempParametes[$tempKey]);

					//return the modified string for replacement
					return $matches[0].$i;
				},$statement),';').';';

			$finalExecute = array_merge($finalExecute,$tempParametes);
		}

		//disable stacking
		$this->stacking = false;

		$this->beginTransaction();

		$req = $this->prepare($finalStatement);

		$success = $req->execute($finalExecute);
		//as we execute multiple query that we don't fetch, we have to close the cursor if we want to do other requests later
		$req->closeCursor();
		$this->commit();
		//using beginTransaction/commit disable the autocommit, we re-activate it
		$this->setAttribute(\PDO::ATTR_AUTOCOMMIT,1);
		parent::setAttribute(\PDO::ATTR_EMULATE_PREPARES, false);
		return $success;
	}
}