消費税

とりあえず、消費税について考えました。
たぶん、もっと考えないといけないのかもしれません。

<?php

function ckdj($strpw){

	$yearpw = substr( $strpw, 0, 4);
	$monthpw = substr( $strpw, 5, 2);
	$daypw = substr( $strpw, 8, 2);
	$hourpw = 0;
	$minutepw = 0;
	$secondpw = 0;
	
	if( checkdate($monthpw, $daypw, $yearpw)){
		$timestamppw = mktime ($hourpw, $minutepw, $secondpw , $monthpw , $daypw , $yearpw );
		return $timestamppw;
	}else{
		return -1;
	}
}

function zeiritsuj($strpw){

/*
1989/04/01 3%
1997/04/01 5%
2014/04/01 8%
2015/09/30 10%
*/
	$in_timestamppw = ckdj($strpw);
	if( $in_timestamppw == -1 ){
	echo "error-desu!!";
	// die();
	}
	
	if( $in_timestamppw < strtotime("1989/04/01") ){
		return 0;
	}elseif( $in_timestamppw >= strtotime("1989/04/01") and $in_timestamppw < strtotime("1997/04/01") ){
		return 0.03;
	}elseif( $in_timestamppw >= strtotime("1997/04/01") and $in_timestamppw < strtotime("2014/04/01") ){
		return 0.05;
	}elseif( $in_timestamppw >= strtotime("2014/04/01") and $in_timestamppw < strtotime("2015/10/01") ){
		return 0.08;
	}elseif( $in_timestamppw >= strtotime("2015/10/01") ){
		return 0.1;
	}
}

function zeikomij($kinpw, $indatepw){
	return $kinpw + ($kinpw * zeiritsuj($indatepw));
}

echo "2015/10/32  ".zeiritsuj("2015/10/32")."<br>\n";
echo "1989/03/31  ".zeiritsuj("1989/03/31")."<br>\n";
echo "1989/04/01  ".zeiritsuj("1989/04/01")."<br>\n";
echo "1997/03/31  ".zeiritsuj("1997/03/31")."<br>\n";
echo "1997/04/01  ".zeiritsuj("1997/04/01")."<br>\n";
echo "2014/03/31  ".zeiritsuj("2014/03/31")."<br>\n";
echo "2014/04/01  ".zeiritsuj("2014/04/01")."<br>\n";
echo "2015/09/30  ".zeiritsuj("2015/09/30")."<br>\n";
echo "2015/10/01  ".zeiritsuj("2015/10/01")."<br>\n";

/*
error-desu!!2015/10/32 0
1989/03/31 0
1989/04/01 0.03
1997/03/31 0.03
1997/04/01 0.05
2014/03/31 0.05
2014/04/01 0.08
2015/09/30 0.08
2015/10/01 0.1
*/
?>