package PPI::Util;
# Provides some common utility functions that can be imported
use strict;
use Exporter     ();
use Digest::MD5  ();
use Params::Util qw{_INSTANCE _SCALAR0 _ARRAY0};
our $VERSION = '1.281';
our @ISA       = 'Exporter';
our @EXPORT_OK = qw{ _Document _slurp };
# 5.8.7 was the first version to resolve the notorious
# "unicode length caching" bug.
use constant HAVE_UNICODE => !! ( $] >= 5.008007 );
# Common reusable true and false functions
# This makes it easy to upgrade many places in PPI::XS
sub TRUE  () { 1  }
sub FALSE () { '' }
#####################################################################
# Functions
# Allows a sub that takes a L<PPI::Document> to handle the full range
# of different things, including file names, SCALAR source, etc.
sub _Document {
        shift if @_ > 1;
        return undef unless defined $_[0];
        require PPI::Document;
        return PPI::Document->new(shift) unless ref $_[0];
        return PPI::Document->new(shift) if _SCALAR0($_[0]);
        return PPI::Document->new(shift) if _ARRAY0($_[0]);
        return shift if _INSTANCE($_[0], 'PPI::Document');
        return undef;
}
# Provide a simple _slurp implementation
sub _slurp {
        my $file = shift;
        local $/ = undef;
        local *FILE;
        open( FILE, '<', $file ) or return "open($file) failed: $!";
        my $source = <FILE>;
        close( FILE ) or return "close($file) failed: $!";
        return \$source;
}
# Provides a version of Digest::MD5's md5hex that explicitly
# works on the unix-newlined version of the content.
sub md5hex {
        my $string = shift;
        $string =~ s/(?:\015{1,2}\012|\015|\012)/\015/gs;
        Digest::MD5::md5_hex($string);
}
# As above but slurps and calculates the id for a file by name
sub md5hex_file {
        my $file    = shift;
        my $content = _slurp($file);
        return undef unless ref $content;
        $$content =~ s/(?:\015{1,2}\012|\015|\012)/\n/gs;
        md5hex($$content);
}
1;