# $Id: XMLDecl.pm,v 1.3 2003/07/30 13:39:22 matt Exp $

package XML::SAX::PurePerl;

use strict;

use XML::SAX::PurePerl::Productions qw($S $VersionNum $EncNameStart $EncNameEnd);

sub XMLDecl {

    my ($self, $reader) = @_;

    my $data = $reader->data(5);

    # warn("Looking for xmldecl in: $data");

    if ($data =~ /^<\?xml$S/o) {

        $reader->move_along(5);

        $self->skip_whitespace($reader);

        # get version attribute

        $self->VersionInfo($reader) || 

            $self->parser_error("XML Declaration lacks required version attribute, or version attribute does not match XML specification", $reader);

        if (!$self->skip_whitespace($reader)) {

            my $data = $reader->data(2);

            $data =~ /^\?>/ or $self->parser_error("Syntax error", $reader);

            $reader->move_along(2);

            return;

        }

        if ($self->EncodingDecl($reader)) {

            if (!$self->skip_whitespace($reader)) {

                my $data = $reader->data(2);

                $data =~ /^\?>/ or $self->parser_error("Syntax error", $reader);

                $reader->move_along(2);

                return;

            }

        }

        $self->SDDecl($reader);

        $self->skip_whitespace($reader);

        my $data = $reader->data(2);

        $data =~ /^\?>/ or $self->parser_error("Syntax error", $reader);

        $reader->move_along(2);

    }

    else {

        # warn("first 5 bytes: ", join(',', unpack("CCCCC", $data)), "\n");

        # no xml decl

        if (!$reader->get_encoding) {

            $reader->set_encoding("UTF-8");

        }

    }

}

sub VersionInfo {

    my ($self, $reader) = @_;

    my $data = $reader->data(11);

    # warn("Looking for version in $data");

    $data =~ /^(version$S*=$S*(["'])($VersionNum)\2)/o or return 0;

    $reader->move_along(length($1));

    my $vernum = $3;

    if ($vernum ne "1.0") {

        $self->parser_error("Only XML version 1.0 supported. Saw: '$vernum'", $reader);

    }

    return 1;

}

sub SDDecl {

    my ($self, $reader) = @_;

    my $data = $reader->data(15);

    $data =~ /^(standalone$S*=$S*(["'])(yes|no)\2)/o or return 0;

    $reader->move_along(length($1));

    my $yesno = $3;

    if ($yesno eq 'yes') {

        $self->{standalone} = 1;

    }

    else {

        $self->{standalone} = 0;

    }

    return 1;

}

sub EncodingDecl {

    my ($self, $reader) = @_;

    my $data = $reader->data(12);

    $data =~ /^(encoding$S*=$S*(["'])($EncNameStart$EncNameEnd*)\2)/o or return 0;

    $reader->move_along(length($1));

    my $encoding = $3;

    $reader->set_encoding($encoding);

    return 1;

}

sub TextDecl {

    my ($self, $reader) = @_;

    my $data = $reader->data(6);

    $data =~ /^<\?xml$S+/ or return;

    $reader->move_along(5);

    $self->skip_whitespace($reader);

    if ($self->VersionInfo($reader)) {

        $self->skip_whitespace($reader) ||

                $self->parser_error("Lack of whitespace after version attribute in text declaration", $reader);

    }

    $self->EncodingDecl($reader) ||

        $self->parser_error("Encoding declaration missing from external entity text declaration", $reader);

    $self->skip_whitespace($reader);

    $data = $reader->data(2);

    $data =~ /^\?>/ or $self->parser_error("Syntax error", $reader);

    return 1;

}

1;