#! /usr/bin/perl 
use Getopt::Long;
use strict;

my @optlist = ("h|help!","v|verbose!","cp|classpath=s","J=s", "t|toplevel=s", "rt|runtime!");
my $result = GetOptions @optlist;
our ($opt_h, $opt_v, $opt_cp, $opt_J, $opt_t, $opt_rt);

# -h option 
if ($opt_h) { 
    usage();  
    exit 1;
}

# local variables
my $java = "java";
my $classpath;
my $opts;
my $class;
my @args;

# set $class and @args
if ($opt_t) {
    if (@ARGV > 0) {
	usage();  
	exit 1;
    } else { # $opt_t && @ARGV <= 0
	$class = "com.googlecode.prolog_cafe.lang.PrologMain";
	@args  = ($opt_t);
    }
} elsif (@ARGV > 0) { # !$opt_t && @ARGV > 0
    ($class, @args) = @ARGV;
} else { # !$opt_t && @ARGV <= 0
    $class = "com.googlecode.prolog_cafe.lang.PrologMain";
    @args  = "com.googlecode.prolog_cafe.builtin:cafeteria";
}

# set $classpath
$classpath = "\$PLCAFEDIR/plcafe.jar";
if ($opt_rt) {
    $classpath = "\$PLCAFEDIR/lang.jar:\$PLCAFEDIR/builtin.jar";
} 
$classpath .= ":\$CLASSPATH";
if ($opt_cp) { # -cp option
    $classpath = "$opt_cp:$classpath";
} 
#$classpath = ".:$classpath";

# set $opts
if ($opt_J) { # -J option
    if ($opt_J =~ /(-cp|-classpath)\s+/) {
	&error("can not use $1 in -J option");
    }
    $opts .= $opt_J;
}

my $cmd = "$java $opts -cp $classpath $class @args";
&message("{Enjoy Prolog Cafe!}");
&message($cmd);
system($cmd) && error("launching fails");
&message("{Thank you for using Prolog Cafe!}\n");

exit 0;

sub usage {
    print "\nUsage: $0 [-options] [class] [args...]\n";
    print "\n";
    print "where options support:\n\n";
    print "\t-h -help         : print this help\n";
    print "\t-v -verbose      : enable verbose output\n";
    print "\t-cp -classpath <class search path of directories and zip/jar files>\n";
    print "\t                 : A : separated list of directories and zip/jar files.\n";
    print "\t-rt -runtime     : boot a runtime environment,\n";
    print "\t                 : not including compiler system\n";
    print "\t-t -toplevel <predicate name possibly with package name>\n";
    print "\t                 : set toplevel goal limited to atom\n";
    print "\t                 : (ex. -t main)\n";
    print "\t                 : (ex. -t package:main)\n";
    print "\t                 : Note that class and args must be empty.\n";
    print "\t-J option        : option must be enclosed by '.\n";
    print "\t                 : pass option to the Java Virtual Machine\n";
    print "\t                 : (ex. -J '-Xmx100m -verbose:gc')\n";
    print "\n";
}

sub message {
    my ($x) = @_;
    if ($opt_v) { # check -v option
	print "\% $x\n";
    }
}

sub error {
    my ($x) = @_;
    print "\% ERROR: $x: $0\n";
    exit(1);
}