#!/usr/bin/env perl

use strict;
use warnings;

use Getopt::Std qw(getopts);

my %opts;
getopts("m:", \%opts) or usage();

my $mode = $opts{m};

if (!defined $mode) {
    die "No -m option specified.\n";
}

my $mod = $opts{m};

if (@ARGV < 2) {
    usage();
}

my $dst = pop;

my @src = @ARGV;

my $target_dir;

if (@src > 1 || $dst =~ m{/$}) {
    $target_dir = $dst;

} elsif (-d $dst) {
    $target_dir = $dst;

} elsif ($dst =~ m{(.+)/}) {
    $target_dir = $1;

} else {
    $target_dir = '.';
}

if (!-d $target_dir) {
    shell("mkdir -p $target_dir");
}

shell("cp @src $dst");

if (-f $dst) {
    chmod oct($mode), $dst or
        die "failed to change mode of $dst to $mode.\n";

    exit;
}

for my $src (@src) {
    my $name;

    if ($src =~ m{/([^/]+)$}) {
        $name = $1;

    } else {
        $name = $src;
    }

    my $target = "$target_dir/$name";
    chmod oct($mode), $target or
        die "failed to change mode of $target to $mode.\n";
}

sub usage {
    die "Usage: install -m <attrs> <src>... <dst>\n";
}

sub shell {
    my $cmd = shift;
    system($cmd) == 0 or
        die "failed to run command $cmd\n";
}