#! @perl@ -w @perlFlags@

use strict;
use Nix::SSH;
use Nix::Config;
use Nix::Store;
use Nix::CopyClosure;
use List::Util qw(sum);

binmode STDERR, ":encoding(utf8)";

if (scalar @ARGV < 1) {
    print STDERR <<EOF
Usage: nix-copy-closure [--from | --to] HOSTNAME [--sign] [--gzip] [--bzip2] [--xz] PATHS...
EOF
    ;
    exit 1;
}


# Get the target host.
my $sshHost;
my $sign = 0;
my $toMode = 1;
my $includeOutputs = 0;
my $dryRun = 0;
my $useSubstitutes = 0;


# !!! Copied from nix-pack-closure, should put this in a module.
my @storePaths = ();

while (@ARGV) {
    my $arg = shift @ARGV;

    if ($arg eq "--help") {
        exec "man nix-copy-closure" or die;
    }
    elsif ($arg eq "--sign") {
        $sign = 1;
    }
    elsif ($arg eq "--gzip" || $arg eq "--bzip2" || $arg eq "--xz") {
        warn "$0: ‘$arg’ is not implemented\n" if $arg ne "--gzip";
        push @globalSshOpts, "-C";
    }
    elsif ($arg eq "--from") {
        $toMode = 0;
    }
    elsif ($arg eq "--to") {
        $toMode = 1;
    }
    elsif ($arg eq "--include-outputs") {
        $includeOutputs = 1;
    }
    elsif ($arg eq "--show-progress") {
        warn "$0: ‘$arg’ is not implemented\n";
    }
    elsif ($arg eq "--dry-run") {
        $dryRun = 1;
    }
    elsif ($arg eq "--use-substitutes" || $arg eq "-s") {
        $useSubstitutes = 1;
    }
    elsif (!defined $sshHost) {
        $sshHost = $arg;
    }
    else {
        push @storePaths, $arg;
    }
}

die "$0: you did not specify a host name\n" unless defined $sshHost;


if ($toMode) { # Copy TO the remote machine.
    Nix::CopyClosure::copyTo(
        $sshHost, [ @storePaths ],
        $includeOutputs, $dryRun, $sign, $useSubstitutes);
}

else { # Copy FROM the remote machine.

    my ($from, $to) = connectToRemoteNix($sshHost, []);

    # Query the closure of the given store paths on the remote
    # machine.  Paths are assumed to be store paths; there is no
    # resolution (following of symlinks).
    syswrite($to, pack("L<x4L<x4", 7, $includeOutputs ? 1 : 0)) or die;
    writeStrings(\@storePaths, $to);
    my @missing = grep { !isValidPath($_) } readStrings($from);

    # Export the store paths on the remote machine and import them locally.
    if (scalar @missing > 0) {
        print STDERR "copying ", scalar @missing, " missing paths from ‘$sshHost’...\n";
        writeInt(5, $to); # == cmdExportPaths
        writeInt($sign ? 1 : 0, $to);
        writeStrings(\@missing, $to);
        importPaths(fileno($from));
    }

}