#! /usr/local/bin/perl
pipe(read_1,write_1);  # open pipe 1
pipe(read_2,write_2);  # open pipe 2

# unbuffer all i/o on the pipes
$old_h=select(read_1);
$|=1;
select(read_2);
$|=1;
select(write_1);
$|=1;
select(write_2);
$|=1;
select($old_h);
$|=1;

if ($pid=fork) {
    # the parent do not do anything here} 
    # so close off the read_1 and write_2
    # hence wirte to write_1 and get results off read_2
    $old_h=select(read_2);
    $|=1;
    select(write_1);
    $|=1;
    select($old_h);
    close(read_1);
    close(write_2);
} elsif (defined $pid) {
    # this is the child so...
    # close off read_2 and write_1
    # redirect stdin to read_1 and stdout to write_2
    # then start up the work code
    $old_h=select(read_1);
    $|=1;
    select(write_2);
    $|=1;
    select($old_h);
    close(read_2);
    close(write_1);

    close(STDOUT);
    open(STDOUT,">& write_2");
    select(STDOUT);
    
    close(STDIN);
    open(STDIN,"<& read_1");
    close(read_1);
 
    sleep(1); 

    system("/data/02/steve/mag_stuff/calc_mag");
    die "ending child\n";
}


# read in cnss catalog
# find the locations, magnitude, and amp lines
# store the info for locataion and magnitude
# amp lines calc the new amps.

# for this test calculate ms and mb and see if
# the averages is close to the preferred mag
$amp_loc=45;			# amp_type in $amp line
$mag_loc=10;			# mag_type in $mag line

print write_1 "ARC LZ 6.654  0.0459 0.2 119.5 33.0\n";
$new_line=<read_2>;
print $new_line;
while (<>) {
#    print "$_";
    if (/^\$end/) {
	$t_mag/=$mag_count if ($mag_count!=0);
	printf "total mag = %4.2f pref mag = %4.2f\n",$t_mag,$pref_mag if ($found);

	$st_mag/=$sm_count if ($sm_count!=0);
	printf "BK avg mag = %4.2f\n",$st_mag;
	$mag_count=0;
	$t_mag=0;
	$st_mag=0;
	$sm_count=0;
	$found=0;
	$pref_mag=0;

    } elsif (/^\$mag/) {
	$c_mag=substr($_,5,5);
	$mag_count+=1;
	$t_mag+=$c_mag;
	if (/^\$magP/) { $pref_mag=$c_mag;}
    } elsif (/^\$loc/) {
	if (/NEI/) {
	    ($lat,$lon,$depth)=unpack("x24a9a10a7",$_);
	    $found=1;
	}
    } elsif (/^\$amp/) {
	($station,$amp,$a_type,$freq)=unpack("x23a4x3a6x9a2x5a6",$_);
	if ($found) {
	    if ($amp>0 && ($a_type eq "PZ" ||$a_type eq "LZ" )) {
#	    print "$station $a_type $amp $freq $lat $lon $depth\n";
		print write_1 "$station $a_type $amp $freq $lat $lon $depth\n";
		$new_line=<read_2>;
#	    print $new_line;
		@n=split(/\s+/,$new_line);
		$s_mag=$n[$#n];
		$st_mag+=$s_mag;
		$sm_count+=1;
	    } else {
		print "Something wrong $station $a_type $amp $freq $lat $lon $depth\n";    
	    }
	}
    }
}