#!/usr/bin/perl -w

# Copyright (c) 2017-present, Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree. An additional grant
# of patent rights can be found in the PATENTS file in the same directory.

#
#	File: install_apps
#	
#	This is a shortcut program to:
#		mv /home/rdlab/Dropbox/fb_apps /usr/local/tmp
#		cd /usr/local/tmp
#		./fb_apps
#
use strict;
use FindBin	qw/$Bin/;
use File::Copy;
use File::Basename;
use lib $Bin;
use mods::walker qw/eval_version/;

my $Tdir	= '/usr/local/tmp';
my $Sdir	= "$ENV{HOME}/Dropbox/fbc1";
my $Fn		= find_fn($Sdir);
my $Sfn		= "$Sdir/$Fn";
my $Tfn		= "$Tdir/$Fn";
die "Must be root to run.\n" unless ($> == 0);
die "Cannot find or write to the directory $Tdir.\n" unless (-d $Tdir && -w _);
do	{	warn "No $Sfn found, local updates only.\n";
		goto LOCALS_ONLY;
	}  unless (-f $Sfn && -w _);
$SIG{INT}	= sub { exit 22; };
print "This installation will reboot linux. ^C to exit or Return to install ";
<>;

move($Sfn, $Tfn) or die "Could not move $Sfn: $!.\n";
chdir $Tdir;

my $Pid	= fork;
if ($Pid)	{
	waitpid($Pid, 0);
	my $err	= $? >> 8;
	die "$Tfn had a problem: $!.\n" if $err;
	unlink $Tfn;	# No longer needed.
}
else	{
	exec($Tfn);
}
update_ver('/usr/local', 'fbin/config/build_ver.conf');

LOCALS_ONLY:
copy_home_files('/usr/local/fbin/home', '/home/rdlab', 'rdlab');
copy_app_files('/usr/local/fbin/applications', 
	'/usr/share/applications', 'rdlab');
update_favs('/usr/local/fbin/gui_launch');
print "Restarting in 5 seconds.\n";
sleep 5;
restart();
exit 0;

sub update_favs	{
	my $pn	= shift;

	return unless (-e $pn);
	my $pid = fork;
	if ($pid)	{
		waitpid($pid, 0);
		my $err	= $? >> 8;
		die "Problem with $pn: $!.\n" if ($err > 1);
	}
	else	{
		exec($pn);
	}
}

sub copy_app_files     {
        my $fdir        = shift;
        my $todir       = shift;
        my $unam        = shift;

        my @fds         = glob "$fdir/.* $fdir/*";
        my @fns;

        for my $fd (@fds)       {
                push @fns, $fd if (-f $fd);
        }

	my ($lin, $pass, $uid, $gid)	= getpwnam($unam);
        for my $fn (@fns)       {
                my ($name, $dirs, $sfx) = fileparse($fn);
                my $tfn = "$todir/$name";
                # print "I want to copy from $fn to $tfn.\n";
                copy($fn, $tfn) or die "copy fail from $fn to $tfn: $!.\n";
                chown $uid, $gid, $tfn;
        }
}

sub copy_home_files     {
        my $fdir        = shift;
        my $todir       = shift;
        my $unam        = shift;

        my @fds         = glob "$fdir/.* $fdir/*";
        my @fns;

        for my $fd (@fds)       {
                push @fns, $fd if (-f $fd);
        }

	my ($lin, $pass, $uid, $gid)	= getpwnam($unam);
        for my $fn (@fns)       {
                my ($name, $dirs, $sfx) = fileparse($fn);
                my $tfn = "$todir/$name";
                # print "I want to copy from $fn to $tfn.\n";
                copy($fn, $tfn) or die "copy fail from $fn to $tfn: $!.\n";
                chown $uid, $gid, $tfn;
        }
}

sub update_ver  {
        my $dir = shift;
        my $fn  = shift;
        my $sfn = "$dir/$fn";
	my $tfn	= "$dir/tmp/.sw_history";

        return unless (-f $sfn);
	my $ver	= eval_version($Bin);
	my $time	= `date`;
	my $stxt	= $ver . ' at ' . $time;
        open(my $fh, '>>', $tfn) or die "Cannot append to $tfn.\n";
        print $fh $stxt;
        close $fh;
	print "Installed $ver.\n";
}

sub restart	{
	my $pn	= '/sbin/shutdown';	
	my @arg	= (qw/-r now/);

	print "Now rebooting ...\n";
	my $pid	= fork;
	return if $pid;
	system("sleep 3; $pn @arg");
}


sub find_fn	{
	my $dir	= shift;
	my @fns	= glob("$dir/fb_apps_*");

	die "Conflicting packages in $dir.\n" if (@fns > 1);
	do	{	warn "Could not find package in $dir.\n";
			return "$dir/fb_apps_*"; 
		} unless (@fns);
	die "Cannot find file in $dir.\n" unless($fns[0] =~ m{/(fb_apps_.+)$});
	my $fn	= $1;
	return $fn;
}