package ExtUtils::Install;

use 5.00503;
use vars qw(@ISA @EXPORT $VERSION);
$VERSION = 1.29;

use Exporter;
use Carp ();
use Config qw(%Config);
@ISA = ('Exporter');
@EXPORT = ('install','uninstall','pm_to_blib', 'install_default');
$Is_VMS = $^O eq 'VMS';

my $splitchar = $^O eq 'VMS' ? '|' : ($^O eq 'os2' || $^O eq 'dos') ? ';' : ':';
my @PERL_ENV_LIB = split $splitchar, defined $ENV{'PERL5LIB'} ? $ENV{'PERL5LIB'} : $ENV{'PERLLIB'} || '';
my $Inc_uninstall_warn_handler;

# install relative to here

my $INSTALL_ROOT = $ENV{PERL_INSTALL_ROOT};

use File::Spec;

sub install_rooted_file {
    if (defined $INSTALL_ROOT) {
	File::Spec->catfile($INSTALL_ROOT, $_[0]);
    } else {
	$_[0];
    }
}

sub install_rooted_dir {
    if (defined $INSTALL_ROOT) {
	File::Spec->catdir($INSTALL_ROOT, $_[0]);
    } else {
	$_[0];
    }
}

#our(@EXPORT, @ISA, $Is_VMS);
#use strict;

sub forceunlink {
    chmod 0666, $_[0];
    unlink $_[0] or Carp::croak("Cannot forceunlink $_[0]: $!")
}

sub install {
    my($hash,$verbose,$nonono,$inc_uninstall) = @_;
    $verbose ||= 0;
    $nonono  ||= 0;

    use Cwd qw(cwd);
    use ExtUtils::Packlist;
    use File::Basename qw(dirname);
    use File::Copy qw(copy);
    use File::Find qw(find);
    use File::Path qw(mkpath);
    use File::Compare qw(compare);
    use File::Spec;

    my(%hash) = %$hash;
    my(%pack, $dir, $warn_permissions);
    my($packlist) = ExtUtils::Packlist->new();
    # -w doesn't work reliably on FAT dirs
    $warn_permissions++ if $^O eq 'MSWin32';
    local(*DIR);
    for (qw/read write/) {
	$pack{$_}=$hash{$_};
	delete $hash{$_};
    }
    my($source_dir_or_file);
    foreach $source_dir_or_file (sort keys %hash) {
	#Check if there are files, and if yes, look if the corresponding
	#target directory is writable for us
	opendir DIR, $source_dir_or_file or next;
	for (readdir DIR) {
	    next if $_ eq "." || $_ eq ".." || $_ eq ".exists";
		my $targetdir = install_rooted_dir($hash{$source_dir_or_file});
	    if (-w $targetdir ||
		mkpath($targetdir)) {
		last;
	    } else {
		warn "Warning: You do not have permissions to " .
		    "install into $hash{$source_dir_or_file}"
		    unless $warn_permissions++;
	    }
	}
	closedir DIR;
    }
    my $tmpfile = install_rooted_file($pack{"read"});
    $packlist->read($tmpfile) if (-f $tmpfile);
    my $cwd = cwd();

    my($source);
    MOD_INSTALL: foreach $source (sort keys %hash) {
	#copy the tree to the target directory without altering
	#timestamp and permission and remember for the .packlist
	#file. The packlist file contains the absolute paths of the
	#install locations. AFS users may call this a bug. We'll have
	#to reconsider how to add the means to satisfy AFS users also.

	#October 1997: we want to install .pm files into archlib if
	#there are any files in arch. So we depend on having ./blib/arch
	#hardcoded here.

	my $targetroot = install_rooted_dir($hash{$source});

	if ($source eq "blib/lib" and
	    exists $hash{"blib/arch"} and
	    directory_not_empty("blib/arch")) {
	    $targetroot = install_rooted_dir($hash{"blib/arch"});
            print "Files found in blib/arch: installing files in blib/lib into architecture dependent library tree\n" if $verbose;
	}
	chdir($source) or next;
	find(sub {
	    my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
                         $atime,$mtime,$ctime,$blksize,$blocks) = stat;
	    return unless -f _;
	    return if $_ eq ".exists";
	    my $targetdir  = File::Spec->catdir($targetroot, $File::Find::dir);
	    my $targetfile = File::Spec->catfile($targetdir, $_);

	    my $diff = 0;
	    if ( -f $targetfile && -s _ == $size) {
		# We have a good chance, we can skip this one
		$diff = compare($_,$targetfile);
	    } else {
		print "$_ differs\n" if $verbose>1;
		$diff++;
	    }

	    if ($diff){
		if (-f $targetfile){
		    forceunlink($targetfile) unless $nonono;
		} else {
		    mkpath($targetdir,0,0755) unless $nonono;
		    print "mkpath($targetdir,0,0755)\n" if $verbose>1;
		}
		copy($_,$targetfile) unless $nonono;
		print "Installing $targetfile\n";
		utime($atime,$mtime + $Is_VMS,$targetfile) unless $nonono>1;
		print "utime($atime,$mtime,$targetfile)\n" if $verbose>1;
		$mode = 0444 | ( $mode & 0111 ? 0111 : 0 );
		chmod $mode, $targetfile;
		print "chmod($mode, $targetfile)\n" if $verbose>1;
	    } else {
		print "Skipping $targetfile (unchanged)\n" if $verbose;
	    }
	    
	    if (! defined $inc_uninstall) { # it's called 
	    } elsif ($inc_uninstall == 0){
		inc_uninstall($_,$File::Find::dir,$verbose,1); # nonono set to 1
	    } else {
		inc_uninstall($_,$File::Find::dir,$verbose,0); # nonono set to 0
	    }
	    # Record the full pathname.
	    $packlist->{$targetfile}++;

	}, ".");
	chdir($cwd) or Carp::croak("Couldn't chdir to $cwd: $!");
    }
    if ($pack{'write'}) {
	$dir = install_rooted_dir(dirname($pack{'write'}));
	mkpath($dir,0,0755);
	print "Writing $pack{'write'}\n" if $verbose;
	$packlist->write(install_rooted_file($pack{'write'}));
    }
}

sub directory_not_empty ($) {
  my($dir) = @_;
  my $files = 0;
  find(sub {
	   return if $_ eq ".exists";
	   if (-f) {
	     $File::Find::prune++;
	     $files = 1;
	   }
       }, $dir);
  return $files;
}

sub install_default {
  @_ < 2 or die "install_default should be called with 0 or 1 argument";
  my $FULLEXT = @_ ? shift : $ARGV[0];
  defined $FULLEXT or die "Do not know to where to write install log";
  my $INST_LIB = File::Spec->catdir(File::Spec->curdir,"blib","lib");
  my $INST_ARCHLIB = File::Spec->catdir(File::Spec->curdir,"blib","arch");
  my $INST_BIN = File::Spec->catdir(File::Spec->curdir,'blib','bin');
  my $INST_SCRIPT = File::Spec->catdir(File::Spec->curdir,'blib','script');
  my $INST_MAN1DIR = File::Spec->catdir(File::Spec->curdir,'blib','man1');
  my $INST_MAN3DIR = File::Spec->catdir(File::Spec->curdir,'blib','man3');
  install({
	   read => "$Config{sitearchexp}/auto/$FULLEXT/.packlist",
	   write => "$Config{installsitearch}/auto/$FULLEXT/.packlist",
	   $INST_LIB => (directory_not_empty($INST_ARCHLIB)) ?
			 $Config{installsitearch} :
			 $Config{installsitelib},
	   $INST_ARCHLIB => $Config{installsitearch},
	   $INST_BIN => $Config{installbin} ,
	   $INST_SCRIPT => $Config{installscript},
	   $INST_MAN1DIR => $Config{installman1dir},
	   $INST_MAN3DIR => $Config{installman3dir},
	  },1,0,0);
}

sub uninstall {
    use ExtUtils::Packlist;
    my($fil,$verbose,$nonono) = @_;
    die "no packlist file found: $fil" unless -f $fil;
    # my $my_req = $self->catfile(qw(auto ExtUtils Install forceunlink.al));
    # require $my_req; # Hairy, but for the first
    my ($packlist) = ExtUtils::Packlist->new($fil);
    foreach (sort(keys(%$packlist))) {
	chomp;
	print "unlink $_\n" if $verbose;
	forceunlink($_) unless $nonono;
    }
    print "unlink $fil\n" if $verbose;
    forceunlink($fil) unless $nonono;
}

sub inc_uninstall {
    my($file,$libdir,$verbose,$nonono) = @_;
    my($dir);
    my %seen_dir = ();
    foreach $dir (@INC, @PERL_ENV_LIB, @Config{qw(archlibexp
						  privlibexp
						  sitearchexp
						  sitelibexp)}) {
	next if $dir eq ".";
	next if $seen_dir{$dir}++;
	my($targetfile) = File::Spec->catfile($dir,$libdir,$file);
	next unless -f $targetfile;

	# The reason why we compare file's contents is, that we cannot
	# know, which is the file we just installed (AFS). So we leave
	# an identical file in place
	my $diff = 0;
	if ( -f $targetfile && -s _ == -s $file) {
	    # We have a good chance, we can skip this one
	    $diff = compare($file,$targetfile);
	} else {
	    print "#$file and $targetfile differ\n" if $verbose>1;
	    $diff++;
	}

	next unless $diff;
	if ($nonono) {
	    if ($verbose) {
		$Inc_uninstall_warn_handler ||= new ExtUtils::Install::Warn;
		$libdir =~ s|^\./||s ; # That's just cosmetics, no need to port. It looks prettier.
		$Inc_uninstall_warn_handler->add("$libdir/$file",$targetfile);
	    }
	    # if not verbose, we just say nothing
	} else {
	    print "Unlinking $targetfile (shadowing?)\n" if $verbose;
	    forceunlink($targetfile);
	}
    }
}

sub run_filter {
    my ($cmd, $src, $dest) = @_;
    open(CMD, "|$cmd >$dest") || die "Cannot fork: $!";
    open(SRC, $src)           || die "Cannot open $src: $!";
    my $buf;
    my $sz = 1024;
    while (my $len = sysread(SRC, $buf, $sz)) {
	syswrite(CMD, $buf, $len);
    }
    close SRC;
    close CMD or die "Filter command '$cmd' failed for $src";
}

sub pm_to_blib {
    my($fromto,$autodir,$pm_filter) = @_;

    use File::Basename qw(dirname);
    use File::Copy qw(copy);
    use File::Path qw(mkpath);
    use File::Compare qw(compare);
    use AutoSplit;
    # my $my_req = $self->catfile(qw(auto ExtUtils Install forceunlink.al));
    # require $my_req; # Hairy, but for the first

    if (!ref($fromto) && -r $fromto)
     {
      # Win32 has severe command line length limitations, but
      # can generate temporary files on-the-fly
      # so we pass name of file here - eval it to get hash 
      open(FROMTO,"<$fromto") or die "Cannot open $fromto:$!";
      my $str = '$fromto = {qw{'.join('',<FROMTO>).'}}';
      eval $str;
      close(FROMTO);
     }

    mkpath($autodir,0,0755);
    foreach (keys %$fromto) {
	my $dest = $fromto->{$_};
	next if -f $dest && -M $dest < -M $_;

	# When a pm_filter is defined, we need to pre-process the source first
	# to determine whether it has changed or not.  Therefore, only perform
	# the comparison check when there's no filter to be ran.
	#    -- RAM, 03/01/2001

	my $need_filtering = defined $pm_filter && length $pm_filter && /\.pm$/;

	if (!$need_filtering && 0 == compare($_,$dest)) {
	    print "Skip $dest (unchanged)\n";
	    next;
	}
	if (-f $dest){
	    forceunlink($dest);
	} else {
	    mkpath(dirname($dest),0,0755);
	}
	if ($need_filtering) {
	    run_filter($pm_filter, $_, $dest);
	    print "$pm_filter <$_ >$dest\n";
	} else {
	    copy($_,$dest);
	    print "cp $_ $dest\n";
	}
	my($mode,$atime,$mtime) = (stat)[2,8,9];
	utime($atime,$mtime+$Is_VMS,$dest);
	chmod(0444 | ( $mode & 0111 ? 0111 : 0 ),$dest);
	next unless /\.pm$/;
	autosplit($dest,$autodir);
    }
}

package ExtUtils::Install::Warn;

sub new { bless {}, shift }

sub add {
    my($self,$file,$targetfile) = @_;
    push @{$self->{$file}}, $targetfile;
}

sub DESTROY {
	unless(defined $INSTALL_ROOT) {
		my $self = shift;
		my($file,$i,$plural);
		foreach $file (sort keys %$self) {
		$plural = @{$self->{$file}} > 1 ? "s" : "";
		print "## Differing version$plural of $file found. You might like to\n";
		for (0..$#{$self->{$file}}) {
			print "rm ", $self->{$file}[$_], "\n";
			$i++;
		}
		}
		$plural = $i>1 ? "all those files" : "this file";
		print "## Running 'make install UNINST=1' will unlink $plural for you.\n";
	}
}

1;

__END__

=head1 NAME

ExtUtils::Install - install files from here to there

=head1 SYNOPSIS

B<use ExtUtils::Install;>

B<install($hashref,$verbose,$nonono);>

B<uninstall($packlistfile,$verbose,$nonono);>

B<pm_to_blib($hashref);>

=head1 DESCRIPTION

Both install() and uninstall() are specific to the way
ExtUtils::MakeMaker handles the installation and deinstallation of
perl modules. They are not designed as general purpose tools.

install() takes three arguments. A reference to a hash, a verbose
switch and a don't-really-do-it switch. The hash ref contains a
mapping of directories: each key/value pair is a combination of
directories to be copied. Key is a directory to copy from, value is a
directory to copy to. The whole tree below the "from" directory will
be copied preserving timestamps and permissions.

There are two keys with a special meaning in the hash: "read" and
"write". After the copying is done, install will write the list of
target files to the file named by C<$hashref-E<gt>{write}>. If there is
another file named by C<$hashref-E<gt>{read}>, the contents of this file will
be merged into the written file. The read and the written file may be
identical, but on AFS it is quite likely that people are installing to a
different directory than the one where the files later appear.

install_default() takes one or less arguments.  If no arguments are 
specified, it takes $ARGV[0] as if it was specified as an argument.  
The argument is the value of MakeMaker's C<FULLEXT> key, like F<Tk/Canvas>.  
This function calls install() with the same arguments as the defaults 
the MakeMaker would use.

The argument-less form is convenient for install scripts like

  perl -MExtUtils::Install -e install_default Tk/Canvas

Assuming this command is executed in a directory with a populated F<blib> 
directory, it will proceed as if the F<blib> was build by MakeMaker on 
this machine.  This is useful for binary distributions.

uninstall() takes as first argument a file containing filenames to be
unlinked. The second argument is a verbose switch, the third is a
no-don't-really-do-it-now switch.

pm_to_blib() takes a hashref as the first argument and copies all keys
of the hash to the corresponding values efficiently. Filenames with
the extension pm are autosplit. Second argument is the autosplit
directory.  If third argument is not empty, it is taken as a filter command
to be ran on each .pm file, the output of the command being what is finally
copied, and the source for auto-splitting.

You can have an environment variable PERL_INSTALL_ROOT set which will
be prepended as a directory to each installed file (and directory).

=cut
