<?php
class gausMethod{

    protected $columns ; // koloni, ravni na broq na neizvestni
    protected $rows ;  // redove, ravni na broi uravneniq
    protected $aDeterminanta; // matricata
    protected $values = array();
/*
rows = broi uravneniq
columns = broi neizvestni
 na4in na upotreba: Pyrvite 2 sa redove neizcestni, sled tova se izbroqvat stoinostite pred neizvestnite. red po red.
*/
    public function __construct($rows,$columns){
        $temp = func_get_args();
        $this->rows = $temp[0]; //broi uravneniq
        array_shift(&$temp);
        $this->columns = $temp[0]; //broi neizvestni
        array_shift(&$temp);
        $v = 0;
        for ($i = 0; $i < $this->rows ; $i++) {
            for ($j = 0; $j < $this->columns ; $j++) {
                $aDeterminanta[$i][$j] = $temp[$v];
                $v++;
            }
        }
        $this->convertToTriangularType();
        $this->calculateMatrix();
    }

    public function getMat(){
        return $this->aDeterminanta;
    }



    public function convertToTriangularType(){
        for ($j = 0;$j < $this->columns ;$j++){
            $temp = $this->aDeterminanta[$j][$j];
            for ($i=$j + 1;$i < $this->rows ;$i++){
                $temp2 = $this->aDeterminanta[$i][$j] / -$temp;
                $mRow = $this->muliplyRow($i,$temp2);
                $aRow = $this->addRow($mRow,$i);
                $this->updateRow($i,$aRow);
            }
        }
        for ($j = $this->columns - 1;$j > -1 ;$j--){
            $temp = $this->aDeterminanta[$j][$j];
            for ($i=$j - 1;$i > -1;$i--){
                $temp2 = $this->aDeterminanta[$i][$j] / -$temp;
                $mRow = $this->muliplyRow($i,$temp2);
                $aRow = $this->addRow($mRow,$i);
                $this->updateRow($i,$aRow);
            }
        }
    }

    //iz4islqvane na matricata
    public function calculateMatrix(){
        for ($i=0;$i<$this->rows;$i++){
            $temp = $this->aDeterminanta[$i][$this->columns];
            echo "Neizvestna $i e $temp";
        }
    }


    /*@Function@ multiplyRow @@
     *
     * Action:
     *  Multiply's a row by a number
     * Return:
     *  Row multiplied by number
     * Arguments:
     *  $rowToMultiply: Koi red da se umnoji
     *  $amountToMultiplyBy: S kolko da go umnoji
     *
     * @@End@@*/
    private function muliplyRow($rowToMultiply,$amountToMultiplyBy){
        $temp = $this->aDeterminanta[$rowToMultiply];
        for ($i = 0; $i < $this->columns; $i++) {
            $temp[$i] = $temp[$i] * $amountToMultiplyBy;
        }
        return $temp;
    }

    private function addRow($rowToAdd,$rowToAddTo){
        $temp = $this->aDeterminanta[$rowToAddTo];
        for ($i = 0;$i <$this->columns;$i++){
            $temp[$i] = $temp[$i] + $rowToAdd[$i];
        }
        return $temp;
    }

    private function updateRow($rowToUpdate,$newRow){
        $this->aDeterminanta[$rowToUpdate] = $newRow;
    }


    private function switchRows($nRowToSwith,$nRowToSwitchWith){
        if($nRowToSwith > $this->rows || $nRowToSwitchWith > $this->rows){
            Throw new Exception('Invalid aruments in switchRows function');
        }
        $temp = $this->aDeterminanta[$nRowToSwitchWith];
        $this->aDeterminanta[$nRowToSwitchWith] = $this->aDeterminanta[$nRowToSwith];
        $this->aDeterminanta[$nRowToSwith] = $temp;
    }

    private function AnalyzeFirstRow(){ //Analizirane na 1-iq stylb v tyrsene na 1-ca, razmnqne na redove.
        if ($this->aDeterminanta[0][0] == 1) { //ako pyrvoto 4islo e 1, spira funkciqta
            return;
        }
        for ($i = 1; $i < $this->rows; $i++) {
            if ($this->aDeterminanta[i][0] == 1) {
                $this->switchRows($this->aDeterminanta[i],$this->aDeterminanta[0]);
                break;
            }
        }
    }


}


$matrix = new gausMethod(4,4,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15);
?>