# $Id: Exception.pm,v 1.2 2001/11/14 11:07:25 matt Exp $

package XML::SAX::PurePerl::Exception;

use strict;

use overload '""' => "stringify";

use vars qw/$StackTrace/;

$StackTrace = $ENV{XML_DEBUG} || 0;

sub throw {

    my $class = shift;

    die $class->new(@_);

}

sub new {

    my $class = shift;

    my %opts = @_;

    die "Invalid options" unless exists $opts{Message};

    if ($opts{reader}) {

        return bless { Message => $opts{Message},

                        Exception => undef, # not sure what this is for!!!

                        ColumnNumber => $opts{reader}->column,

                        LineNumber => $opts{reader}->line,

                        PublicId => $opts{reader}->public_id,

                        SystemId => $opts{reader}->system_id,

                        $StackTrace ? (StackTrace => stacktrace()) : (),

                    }, $class;

    }

    return bless { Message => $opts{Message},

                    Exception => undef, # not sure what this is for!!!

                  }, $class;

}

sub stringify {

    my $self = shift;

    local $^W;

    return $self->{Message} . " [Ln: " . $self->{LineNumber} . 

                ", Col: " . $self->{ColumnNumber} . "]" .

                ($StackTrace ? stackstring($self->{StackTrace}) : "") . "\n";

}

sub stacktrace {

    my $i = 2;

    my @fulltrace;

    while (my @trace = caller($i++)) {

        my %hash;

        @hash{qw(Package Filename Line)} = @trace[0..2];

        push @fulltrace, \%hash;

    }

    return \@fulltrace;

}

sub stackstring {

    my $stacktrace = shift;

    my $string = "\nFrom:\n";

    foreach my $current (@$stacktrace) {

        $string .= $current->{Filename} . " Line: " . $current->{Line} . "\n";

    }

    return $string;

}

1;